/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* University of Michigan Brand Colors */
    --primary-color: #00274c;        /* Michigan Blue */
    --primary-dark: #001a33;         /* Darker Michigan Blue */
    /* --secondary-color: #ffcb05;      Maize */
    --secondary-color: #f3590f;      /* Maize */
    --accent-color: #d73027;         /* Michigan Red */
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --background: #001a33;
    --navbackground: rgba(26, 26, 26, 0.9);
    --surface: #f8fafc;
    --border: #e5e7eb;
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);

    /* Michigan-specific gradients */
    --umich-gradient: linear-gradient(135deg, #00274c 0%, #001a33 50%, #f3590f 100%);
    --umich-gradient-mobile: linear-gradient(180deg, #00274c 0%, #001a33 100%);
    --umich-gradient-subtle: linear-gradient(135deg, rgba(0, 39, 76, 0.9) 0%, rgba(255, 203, 5, 0.1) 100%);

    --navbar-height: 4rem;
    --vh: 1vh;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    overflow-x: hidden;
    border: none;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Source Sans Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-image: url('./fig/background_dark.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-color: var(--background);
    overflow-x: hidden;
    padding-top: env(safe-area-inset-top);
    padding-bottom: env(safe-area-inset-bottom);
    padding-left: env(safe-area-inset-left);
    padding-right: env(safe-area-inset-right);
    border: none; /* 确保没有边框 */
    margin: 0; /* 确保没有外边距 */
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* 统一导航栏 */
.unified-navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--navbackground);
    color: white;
    z-index: 1000;
    transition: var(--navbackground);
    padding: 0.75rem 0;
    min-height: 4rem; /* 确保导航栏有最小高度 */
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.unified-navbar.scrolled {
    background: var(--navbackground);
    box-shadow: var(--shadow-lg);
}

.unified-container {
    max-width: none;
    margin: 0;
    padding: 0 0.5rem;
    display: flex;
    justify-content: flex-start;
    align-items: center;
    gap: 1.5rem;
    width: 100%;
}

.umich-logo {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    margin-left: auto;
}

.umich-logo-img {
    height: 2.5rem;
    width: auto;
    /* 保持原始颜色，让M字母显示为黄色 */
}

.lab-logo {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    position: relative;
    left: 0.5rem;
    margin-left: 0;
    gap: 0.75rem;
}

.lab-icon {
    height: 2.5rem;
    width: auto;
    /* 保持原始外观，只控制尺寸 */
}

/* 顶部PixAIL样式 */
.nav-lab-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.nav-lab-name {
    font-family: 'Source Sans Pro', sans-serif;
    font-size: 1.8rem;
    font-weight: 700;
    background: var(--secondary-color);
    color: var(--primary-color);
    padding: 0.4rem 1rem;
    border-radius: 0.5rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.nav-lab-desc {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.9);
    font-weight: 500;
    font-style: italic;
}

.nav-menu {
    display: flex;
    gap: 1.5rem;
    margin-left: 2rem;
    flex-wrap: nowrap;
}

.nav-link {
    font-family: 'Source Sans Pro', sans-serif;
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-weight: 600;
    position: relative;
    transition: var(--transition);
    padding: 0.5rem 0;
    letter-spacing: 0.025em;
}

.nav-link:hover,
.nav-link.active {
    color: var(--secondary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--secondary-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* 汉堡菜单 */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
    padding: 8px;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.hamburger:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.hamburger .bar {
    width: 25px;
    height: 3px;
    background: white;
    border-radius: 2px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.hamburger.active .bar:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active .bar:nth-child(2) {
    opacity: 0;
    transform: translateX(-20px);
}

.hamburger.active .bar:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* 移动菜单遮罩 */
.nav-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.nav-menu-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* 主页部分 */
.hero {
    min-height: 100vh;
    min-height: calc(var(--vh, 1vh) * 100); /* 移动设备优化 */
    display: flex;
    align-items: center;
    background-image: url('./fig/background_dark.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: white;
    position: relative;
    overflow: hidden;
    z-index: 0; /* 确保不会覆盖后面的内容 */
    padding-top: 6rem; /* 为固定导航栏留出更多空间 */
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.2);
    z-index: 1;
}

/* Animated Background Elements */
.hero-background-elements {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: 1;
}

.floating-shape {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    animation: float 20s infinite ease-in-out;
}

.shape-1 {
    width: 300px;
    height: 300px;
    top: 10%;
    left: 5%;
    animation-delay: 0s;
    background: linear-gradient(135deg, rgba(255, 203, 5, 0.1), rgba(0, 39, 76, 0.1));
}

/* .shape-2 {
    width: 200px;
    height: 200px;
    bottom: 15%;
    right: 10%;
    animation-delay: 5s;
    background: linear-gradient(135deg, rgba(0, 39, 76, 0.15), rgba(255, 203, 5, 0.1));
}

.shape-3 {
    width: 150px;
    height: 150px;
    top: 50%;
    right: 20%;
    animation-delay: 10s;
    background: linear-gradient(135deg, rgba(255, 203, 5, 0.12), rgba(0, 39, 76, 0.08));
} */

.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(60px);
    opacity: 0.4;
    animation: pulse-orb 8s infinite ease-in-out;
}

.orb-1 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, var(--secondary-color), transparent);
    top: -100px;
    right: -100px;
    animation-delay: 0s;
}

.orb-2 {
    width: 350px;
    height: 350px;
    background: radial-gradient(circle, var(--primary-color), transparent);
    bottom: -100px;
    left: -100px;
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0) rotate(0deg);
    }
    33% {
        transform: translate(30px, -30px) rotate(120deg);
    }
    66% {
        transform: translate(-20px, 20px) rotate(240deg);
    }
}

@keyframes pulse-orb {
    0%, 100% {
        transform: scale(1);
        opacity: 0.4;
    }
    50% {
        transform: scale(1.2);
        opacity: 0.6;
    }
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    position: relative;
    z-index: 2;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1.3fr;
    gap: 3rem;
    align-items: stretch;
}

.hero-text {
    position: relative;
    z-index: 3;
    display: flex;
    height: 100%;
}

.hero-text-wrapper {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(20px);
    border-radius: 2rem;
    padding: 3rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
    animation: fadeInUp 1s ease-out;
    transition: all 0.3s ease;
    width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.hero-text-wrapper:hover {
    background: rgba(255, 255, 255, 0.08);
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3),
                inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1.2rem;
    background: linear-gradient(135deg, rgba(255, 203, 5, 0.2), rgba(255, 203, 5, 0.1));
    border: 1px solid rgba(255, 203, 5, 0.3);
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 1.5rem;
    animation: fadeInUp 1s ease-out 0.1s both;
    backdrop-filter: blur(10px);
}

.hero-badge i {
    font-size: 1rem;
}

.hero-title {
    font-family: 'Crimson Text', serif;
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.1;
    display: flex;
    flex-direction: row;
    gap: 0.3rem;
    flex-wrap: nowrap;
}

.title-line {
    display: inline-block;
    background: linear-gradient(135deg, #ffffff, rgba(255, 203, 5, 0.9));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 1s ease-out 0.2s both;
    position: relative;
    text-shadow: 0 0 30px rgba(255, 203, 5, 0.3);
    white-space: nowrap;
}

.title-line::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--secondary-color), transparent);
    animation: expandLine 1.5s ease-out 0.8s forwards;
}

@keyframes expandLine {
    to {
        width: 100%;
    }
}

.hero-subtitle-wrapper {
    position: relative;
    margin-bottom: 1.5rem;
    animation: fadeInUp 1s ease-out 0.4s both;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: rgba(255, 255, 255, 0.95);
    font-style: italic;
    letter-spacing: 0.5px;
}

.subtitle-underline {
    width: 80px;
    height: 3px;
    background: linear-gradient(90deg, var(--secondary-color), transparent);
    border-radius: 2px;
    animation: expandLine 1s ease-out 1s forwards;
}

.hero-affiliation {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: rgba(255, 255, 255, 0.85);
    animation: fadeInUp 1s ease-out 0.6s both;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.hero-affiliation i {
    color: var(--secondary-color);
    margin-right: 0.5rem;
    font-size: 1rem;
}

.affiliation-university {
    font-weight: 500;
    color: rgba(255, 255, 255, 0.9);
}



.hero-description {
    font-size: 1.1rem;
    line-height: 1.7;
    margin-bottom: 2rem;
    color: rgba(255, 255, 255, 0.9);
    animation: fadeInUp 1s ease-out 0.6s both;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease-out 0.8s both;
}

.btn {
    font-family: 'Source Sans Pro', sans-serif;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 2rem;
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    letter-spacing: 0.025em;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-openings {
    background: linear-gradient(135deg, var(--secondary-color), #f5d000);
    color: var(--primary-color);
    font-weight: 700;
    position: relative;
    overflow: hidden;
    animation: pulse-glow 2s infinite;
    box-shadow: 0 4px 15px rgba(255, 203, 5, 0.4);
}

.btn-openings::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

.btn-openings:hover::before {
    left: 100%;
}

.btn-openings:hover {
    background: linear-gradient(135deg, #f5d000, var(--secondary-color));
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 203, 5, 0.6);
}

.btn-openings i {
    margin-right: 0.5rem;
}

@keyframes pulse-glow {
    0%, 100% {
        box-shadow: 0 4px 15px rgba(255, 203, 5, 0.4);
    }
    50% {
        box-shadow: 0 4px 20px rgba(255, 203, 5, 0.6);
    }
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: var(--primary-color);
    transform: translateY(-2px);
}

.social-links {
    display: flex;
    gap: 1rem;
    animation: fadeInUp 1s ease-out 0.8s both;
    position: relative;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    color: white;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
}

.social-link::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 203, 5, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s ease, height 0.6s ease;
}

.social-link:hover::before {
    width: 100%;
    height: 100%;
}

.social-link:hover {
    background: rgba(255, 203, 5, 0.2);
    transform: translateY(-5px) scale(1.1);
    border-color: var(--secondary-color);
    box-shadow: 0 8px 20px rgba(255, 203, 5, 0.3);
}

.social-link i {
    position: relative;
    z-index: 1;
    font-size: 1.2rem;
    transition: transform 0.3s ease;
}

.social-link:hover i {
    transform: scale(1.2) rotate(5deg);
}

.social-tooltip {
    position: absolute;
    bottom: -40px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0, 39, 76, 0.9);
    color: white;
    padding: 0.4rem 0.8rem;
    border-radius: 0.5rem;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease, transform 0.3s ease;
    z-index: 10;
}

.social-tooltip::before {
    content: '';
    position: absolute;
    top: -5px;
    left: 50%;
    transform: translateX(-50%);
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-bottom: 5px solid rgba(0, 39, 76, 0.9);
}

.social-link:hover .social-tooltip {
    opacity: 1;
    transform: translateX(-50%) translateY(-5px);
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeInUp 1s ease-out 0.6s both;
    flex: 1;
    max-width: 750px;
    position: relative;
    z-index: 3;
    height: 100%;
}

.photo-carousel-wrapper {
    position: relative;
    width: 100%;
    max-width: 750px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.carousel-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 120%;
    height: 120%;
    background: radial-gradient(circle, rgba(255, 203, 5, 0.2), transparent 70%);
    border-radius: 50%;
    filter: blur(40px);
    animation: pulse-glow 3s infinite ease-in-out;
    z-index: -1;
}

@keyframes pulse-glow {
    0%, 100% {
        opacity: 0.5;
        transform: translate(-50%, -50%) scale(1);
    }
    50% {
        opacity: 0.8;
        transform: translate(-50%, -50%) scale(1.1);
    }
}

/* Photo Carousel Styles */
.photo-carousel {
    position: relative;
    width: 100%;
    max-width: 750px;
    height: 100%;
    border-radius: 2rem;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 39, 76, 0.4),
                0 0 0 1px rgba(255, 255, 255, 0.1),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
    border: 2px solid rgba(255, 203, 5, 0.3);
    background: rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.photo-carousel:hover {
    transform: translateY(-5px);
    box-shadow: 0 25px 70px rgba(0, 39, 76, 0.5),
                0 0 0 1px rgba(255, 203, 5, 0.5),
                inset 0 1px 0 rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 203, 5, 0.5);
}

.carousel-container {
    position: relative;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.carousel-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
}

.carousel-slide.active {
    opacity: 1;
}

.group-photo {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Carousel Navigation Buttons */
.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 39, 76, 0.8);
    backdrop-filter: blur(10px);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.2);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 10;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.carousel-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 203, 5, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.4s ease, height 0.4s ease;
}

.carousel-btn:hover::before {
    width: 100%;
    height: 100%;
}

.carousel-btn:hover {
    background: rgba(255, 203, 5, 0.9);
    border-color: var(--secondary-color);
    transform: translateY(-50%) scale(1.15);
    box-shadow: 0 6px 25px rgba(255, 203, 5, 0.4);
}

.carousel-btn i {
    position: relative;
    z-index: 1;
    transition: transform 0.3s ease;
}

.carousel-btn:hover i {
    transform: scale(1.2);
    color: var(--primary-color);
}

.prev-btn {
    left: 15px;
}

.next-btn {
    right: 15px;
}

/* Carousel Dots */
.carousel-dots {
    position: absolute;
    bottom: 25px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 10;
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.4);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 2px solid rgba(255, 255, 255, 0.6);
    position: relative;
}

.dot::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 203, 5, 0.5);
    transition: width 0.3s ease, height 0.3s ease;
}

.dot:hover {
    background: rgba(255, 203, 5, 0.7);
    transform: scale(1.3);
    border-color: var(--secondary-color);
}

.dot:hover::before {
    width: 100%;
    height: 100%;
}

.dot.active {
    background: var(--secondary-color);
    transform: scale(1.4);
    border-color: var(--secondary-color);
    box-shadow: 0 0 15px rgba(255, 203, 5, 0.6);
}

.dot.active::before {
    width: 100%;
    height: 100%;
    background: rgba(255, 203, 5, 0.3);
}

.profile-image {
    width: 250px;
    height: 250px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

.image-placeholder {
    width: 250px;
    height: 250px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 6rem;
    color: rgba(255, 255, 255, 0.7);
    border: 4px solid rgba(255, 255, 255, 0.2);
}

/* 通用部分样式 */
section {
    padding: 5rem 0;
    scroll-margin-top: calc(4rem + 1rem); /* 导航栏高度 + 额外缓冲 */
    position: relative;
    z-index: 1; /* 确保所有section都在Hero之上 */
}

.section-title {
    font-family: 'Crimson Text', serif;
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-primary);
    position: relative;
}

#research {
    background-image: url('./fig/background_dark.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-color: var(--background);
    padding-top: calc(5rem + 4rem); /* Account for fixed navbar */
}

#research .section-title {
    color: white;
}

#research .section-intro {
    color: rgba(255, 255, 255, 0.9);
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -1rem;
    left: 50%;
    transform: translateX(-50%);
    width: 4rem;
    height: 3px;
    background: var(--primary-color);
    border-radius: 2px;
}

/* 关于部分 */
.about {
    background-image: url('./fig/background_light.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-color: var(--surface);
}

@media (max-width: 768px) {
    .about {
        background-attachment: scroll;
    }
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: start;
}

.about-text {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.about-text p {
    margin-bottom: 1.5rem;
}

.umich-motto {
    margin: 2rem 0;
    padding: 1.5rem;
    background: var(--umich-gradient-subtle);
    border-radius: 0.75rem;
    border-left: 4px solid var(--secondary-color);
}

.umich-motto blockquote {
    margin: 0;
    font-style: italic;
}

.umich-motto p {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    text-align: center;
}

.umich-motto cite {
    display: block;
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-style: normal;
}

.research-interests {
    margin-top: 2rem;
}

.research-interests h3 {
    font-family: 'Crimson Text', serif;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.interests-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.interest-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem;
    background: white;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.interest-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.interest-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.about-sidebar {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.education,
.awards {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
}

.education h3,
.awards h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.education-item {
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border);
}

.education-item:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.degree {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.school {
    font-weight: 500;
    color: var(--primary-color);
    margin-bottom: 0.25rem;
}

.major {
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

.year {
    font-size: 0.9rem;
    color: var(--text-light);
}

.awards ul {
    list-style: none;
}

.awards li {
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border);
    color: var(--text-secondary);
}

.awards li:last-child {
    border-bottom: none;
}

/* 研究部分 */
/* Research Framework Styles */
.section-intro {
    text-align: center;
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin: -1rem auto 3rem;
    line-height: 1.7;
}

/* Research Tabs (Button-like) */
.research-tabs {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    margin-bottom: 2rem;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.research-tab {
    background: white;
    border: 3px solid #e2e8f0;
    border-radius: 1rem;
    padding: 1.5rem 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 39, 76, 0.05);
}

.research-tab:hover {
    transform: translateY(-5px);
    border-color: var(--secondary-color);
    box-shadow: 0 8px 25px rgba(255, 203, 5, 0.3);
}

.research-tab.active {
    background: linear-gradient(135deg, var(--primary-color), #1e3a8a);
    border-color: var(--primary-color);
    box-shadow: 0 8px 25px rgba(0, 39, 76, 0.3);
}

.tab-number {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, #e2e8f0, #cbd5e1);
    color: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.2rem;
    margin: 0 auto 1rem;
    transition: all 0.3s ease;
}

.research-tab.active .tab-number {
    background: var(--secondary-color);
    color: var(--primary-color);
}

.tab-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 0.8rem;
    transition: all 0.3s ease;
}

.research-tab.active .tab-icon {
    color: white;
}

.tab-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary-color);
    transition: all 0.3s ease;
}

.research-tab.active .tab-title {
    color: white;
}

/* Research Panels (Content) */
.research-panels {
    position: relative;
    min-height: 400px;
}

.research-panel {
    display: none;
    opacity: 0;
    animation: fadeIn 0.5s ease-in-out;
}

.research-panel.active {
    display: block;
    opacity: 1;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.panel-header {
    background: linear-gradient(135deg, var(--primary-color), #1e3a8a);
    color: white;
    padding: 2rem;
    border-radius: 1rem;
    margin-bottom: 0;
    box-shadow: 0 8px 30px rgba(0, 39, 76, 0.15);
}

.panel-header h3 {
    font-size: 2rem;
    font-weight: 700;
    margin: 0;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.panel-header i {
    font-size: 2.5rem;
    color: var(--secondary-color);
}

.panel-content {
    background: white;
    padding: 2.5rem;
    border-radius: 0 0 1rem 1rem;
    box-shadow: 0 8px 30px rgba(0, 39, 76, 0.15);
}

.panel-intro {
    font-size: 1.2rem;
    line-height: 1.8;
    color: var(--text-primary);
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid #e2e8f0;
}

.panel-details {
    margin-top: 2rem;
}

.detail-section {
    margin-bottom: 2rem;
}

.detail-section h4 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.detail-section ul {
    list-style: none;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.detail-section li {
    padding: 1rem;
    background: linear-gradient(135deg, #f8fafc, #ffffff);
    border-left: 4px solid var(--secondary-color);
    border-radius: 0.5rem;
    line-height: 1.7;
    transition: all 0.3s ease;
}

.detail-section li:hover {
    transform: translateX(5px);
    box-shadow: 0 4px 15px rgba(0, 39, 76, 0.1);
}

.detail-section li strong {
    color: var(--primary-color);
    font-weight: 700;
}

/* Applications Showcase */
.applications-showcase {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 1.5rem;
}

.app-item {
    background: linear-gradient(135deg, #f8fafc, #ffffff);
    padding: 2rem;
    border-radius: 1rem;
    text-align: center;
    border: 2px solid #e2e8f0;
    transition: all 0.3s ease;
}

.app-item:hover {
    transform: translateY(-5px);
    border-color: var(--secondary-color);
    box-shadow: 0 8px 20px rgba(0, 39, 76, 0.1);
}

.app-item-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color), #1e3a8a);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 2rem;
}

.app-item h5 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.8rem;
}

.app-item p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Old styles kept for compatibility */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.research-card {
    background: white;
    border-radius: 1rem;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.research-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.research-image {
    height: 200px;
    background: var(--umich-gradient-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
}

.research-content {
    padding: 2rem;
}

.research-content h3 {
    font-family: 'Crimson Text', serif;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.research-content p {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

.research-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    padding: 0.25rem 0.75rem;
    background: var(--surface);
    color: var(--primary-color);
    border-radius: 1rem;
    font-size: 0.9rem;
    font-weight: 500;
}

/* Research Framework Layout */
.research-framework {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.research-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
}

.research-row-three {
    display: grid;
    grid-template-columns: 1fr auto 1fr auto 1fr;
    align-items: center;
    gap: 1.5rem;
}

.research-row-single {
    max-width: 100%;
}

.research-block {
    background: white;
    border-radius: 1.5rem;
    padding: 2.5rem 2rem;
    box-shadow: 0 4px 20px rgba(0, 39, 76, 0.1);
    transition: all 0.3s ease;
    position: relative;
    border-top: 5px solid var(--secondary-color);
    text-align: center;
    min-height: 280px;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
}

.research-block:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0, 39, 76, 0.15);
    border-top-color: var(--primary-color);
}

.central-block {
    border-top: 5px solid var(--primary-color);
    background: linear-gradient(135deg, #f8fafc, #ffffff);
    min-height: 180px;
    max-width: 600px;
    margin: 0 auto;
}

.applications-block {
    border-top: 5px solid var(--secondary-color);
    max-width: 900px;
    margin: 0 auto;
}

/* Middle Section Container with Side Arrows */
.middle-section-container {
    display: grid;
    grid-template-columns: 1fr 4fr 1fr;
    align-items: stretch;
    gap: 1rem;
    max-width: 1400px;
    margin: 0 auto;
}

.middle-content {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.side-arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--secondary-color);
    font-size: 2.5rem;
    opacity: 0.8;
    animation: pulse-vertical 2s ease-in-out infinite;
}

.left-arrow,
.right-arrow {
    padding-top: 80px; /* Align with top of central block */
}

/* Arrow Connectors */
.arrow-connector {
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--secondary-color);
    font-size: 2rem;
    opacity: 0.8;
}

.arrow-connector.horizontal i {
    animation: pulse-horizontal 2s ease-in-out infinite;
}

.vertical-arrows {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0.5rem 0;
}

.arrow-down {
    color: var(--secondary-color);
    font-size: 2.5rem;
    opacity: 0.8;
    animation: pulse-vertical 2s ease-in-out infinite;
}

@keyframes pulse-horizontal {
    0%, 100% {
        opacity: 0.8;
        transform: scale(1);
    }
    50% {
        opacity: 1;
        transform: scale(1.1);
    }
}

@keyframes pulse-vertical {
    0%, 100% {
        opacity: 0.8;
        transform: translateY(0);
    }
    50% {
        opacity: 1;
        transform: translateY(5px);
    }
}

/* 出版物部分 */
.publications {
    background-image: url('./fig/background_light.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-color: var(--surface);
    padding: 5rem 0;
}

.publications-intro {
    max-width: 900px;
    margin: 0 auto 4rem;
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.publications-intro a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
}

.publications-intro a:hover {
    text-decoration: underline;
}

.year-navigation {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
    margin: 3rem 0;
    padding: 1rem;
    background: white;
    border-radius: 1rem;
    box-shadow: 0 2px 15px rgba(0, 39, 76, 0.08);
}

.year-nav-btn {
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--primary-color);
    background: white;
    color: var(--primary-color);
    font-size: 1rem;
    font-weight: 600;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.year-nav-btn:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 39, 76, 0.2);
}

.year-nav-btn.active {
    background: var(--primary-color);
    color: white;
}

.publications-timeline {
    max-width: 1000px;
    margin: 0 auto;
}

.year-section {
    margin-bottom: 2rem;
}

.year-header {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 2rem;
    cursor: pointer;
    user-select: none;
}

.year-header:hover .year-title {
    color: var(--secondary-color);
}

.year-title {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    min-width: 150px;
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    transition: color 0.3s ease;
}

.year-icon {
    font-size: 1.2rem;
    transition: transform 0.3s ease;
    transform: rotate(-90deg);
}

.year-section.active .year-icon {
    transform: rotate(0deg);
}

.year-line {
    flex: 1;
    height: 2px;
    background: linear-gradient(to right, var(--primary-color), transparent);
}

.publications-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.year-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease;
}

.year-section.active .year-content {
    max-height: 10000px;
}

.publication-card {
    padding: 2rem;
    background: white;
    border-radius: 1rem;
    box-shadow: 0 2px 15px rgba(0, 39, 76, 0.08);
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
}

.publication-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0, 39, 76, 0.15);
    border-left-color: var(--secondary-color);
}

.publication-card.featured {
    border-left-color: var(--secondary-color);
    background: linear-gradient(135deg, rgba(255, 203, 5, 0.03), rgba(255, 255, 255, 1));
}

.pub-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin: 0 0 0.75rem 0;
    color: var(--text-primary);
    line-height: 1.5;
}

.pub-title a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color 0.2s ease;
}

.pub-title a:hover {
    color: var(--primary-color);
}

.pub-authors {
    color: var(--text-secondary);
    margin: 0 0 0.5rem 0;
    font-size: 0.95rem;
}

.pub-venue {
    color: var(--text-light);
    margin: 0 0 1rem 0;
    font-size: 0.9rem;
}

.pub-award {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: linear-gradient(135deg, rgba(255, 203, 5, 0.15), rgba(255, 203, 5, 0.08));
    border: 1px solid rgba(255, 203, 5, 0.3);
    border-radius: 0.5rem;
    color: var(--primary-color);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.pub-award i {
    color: var(--secondary-color);
}

.pub-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.pub-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.5rem 1rem;
    background: var(--surface);
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 0.5rem;
    font-size: 0.85rem;
    transition: all 0.2s ease;
    transition: var(--transition);
}

.pub-link:hover {
    background: var(--primary-color);
    color: white;
}

.impact-factor {
    background: var(--accent-color);
    color: white;
    padding: 0.2rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.8rem;
    font-weight: 600;
    margin-left: 0.5rem;
}


/* 教学部分 */
.teaching-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.teaching-card {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.teaching-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.teaching-header {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: 1rem;
}

.teaching-header h3 {
    font-family: 'Crimson Text', serif;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.semester {
    background: var(--secondary-color);
    color: var(--primary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.9rem;
    font-weight: 600;
}

.course-description {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

.course-details {
    display: flex;
    gap: 2rem;
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.detail-item i {
    color: var(--primary-color);
}

/* 联系部分 */
.contact {
    background: var(--surface);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: start;
    gap: 1rem;
    padding: 2rem;
    background: white;
    border-radius: 1rem;
    box-shadow: var(--shadow);
}

.contact-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-top: 0.25rem;
}

.contact-item h3 {
    font-family: 'Crimson Text', serif;
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.contact-item p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.contact-form {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: 0.5rem;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* 页脚 */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 2rem 0;
}

.footer-content {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
}

.footer-main {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    text-align: center;
}

.footer-credits {
    padding-top: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    text-align: center;
}

.footer-credits p {
    margin: 0;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.footer-credits i {
    color: var(--secondary-color);
    font-size: 0.9rem;
}

.footer-credits a {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border-bottom: 1px solid transparent;
}

.footer-credits a:hover {
    color: white;
    border-bottom-color: var(--secondary-color);
}

.copyright {
    font-size: 1rem;
    color: white;
    margin: 0;
}

.footer-contact {
    display: flex;
    gap: 3rem;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.9);
}

.footer-contact span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.3s ease;
}

.footer-contact span:hover {
    color: var(--secondary-color);
}

.footer-contact i {
    color: var(--secondary-color);
    font-size: 1rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
}

/* 动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-image {
        max-width: 450px;
        margin: 0 auto;
    }

    .photo-carousel {
        max-width: 450px;
    }

    .carousel-btn {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }

    .prev-btn {
        left: 10px;
    }

    .next-btn {
        right: 10px;
    }

    .hero-title {
        font-size: 3rem;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .about-text {
        font-size: 1rem;
        line-height: 1.7;
    }

    .about-text p {
        margin-bottom: 1.2rem;
    }

    .section-title {
        font-size: 2rem;
        padding: 0 1rem;
    }

    .section-subtitle {
        font-size: 1rem;
        padding: 0 1rem;
    }

    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}

@media (max-width: 768px) {
    /* Fix background-attachment for mobile performance */
    body,
    .page-section,
    .publications,
    .people,
    .about,
    .join-lab {
        background-attachment: scroll !important;
    }

    /* Prevent horizontal overflow globally */
    html, body {
        overflow-x: hidden;
        width: 100%;
        position: relative;
    }

    * {
        box-sizing: border-box;
    }

    img, video, iframe {
        max-width: 100%;
        height: auto;
    }

    .container {
        padding: 0 1rem;
        max-width: 100%;
        overflow-x: hidden;
        width: 100%;
    }

    /* 移动设备hero section调整 */
    .hero {
        padding-top: 7rem; /* 移动设备需要更多上边距 */
        padding-left: 1rem;
        padding-right: 1rem;
        background: var(--umich-gradient-mobile); /* 使用纯蓝色渐变 */
    }

    .hero-container {
        padding: 0 1rem;
    }

    .footer-main {
        gap: 1.5rem;
    }

    .footer-contact {
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }

    .nav-container {
        padding: 0 1rem;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 4rem;
        flex-direction: column;
        background-color: var(--primary-color);
        width: 100%;
        text-align: center;
        transition: left 0.3s ease-in-out;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
        padding: 2rem 0;
        justify-content: flex-start;
        z-index: 1001; /* 确保在导航栏之上 */
        max-height: calc(100vh - 4rem);
        overflow-y: auto;
    }

    .nav-menu.active {
        left: 0;
    }

    .hamburger {
        display: flex;
        min-height: 44px;
        min-width: 44px;
        align-items: center;
        justify-content: center;
        position: relative;
        z-index: 1002; /* 确保在菜单之上 */
        cursor: pointer;
        padding: 8px;
    }

    .nav-link {
        padding: 1.2rem 2rem;
        min-height: 44px;
        display: flex;
        align-items: center;
        justify-content: center;
        width: 100%;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        transition: all 0.3s ease;
    }

    .nav-link:hover {
        background-color: rgba(255, 255, 255, 0.1);
        color: var(--secondary-color);
    }

    .nav-link:last-child {
        border-bottom: none;
    }

    /* 移动设备统一导航栏调整 */
    .unified-navbar {
        padding: 0.75rem 0;
        height: auto;
        min-height: 5rem; /* 增加移动设备导航栏高度 */
        position: fixed;
        width: 100%;
        top: 0;
        box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
    }

    /* 调整页面内容的上边距 */
    .page-section {
        padding-top: 6rem;
    }

    .hero {
        padding-top: 7rem; /* 更新为与上面一致 */
        min-height: calc(100vh - 5rem);
    }

    .unified-container {
        padding: 0 1rem;
        display: flex;
        justify-content: flex-end; /* 只在右侧显示汉堡菜单 */
        align-items: center;
    }

    /* 在移动设备上隐藏logo和其他元素 */
    .lab-logo,
    .umich-logo,
    .nav-lab-info {
        display: none !important;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 5rem; /* 匹配移动设备导航栏高度 */
        flex-direction: column;
        background-color: var(--primary-color);
        width: 100%;
        text-align: center;
        transition: left 0.3s ease-in-out;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
        padding: 2rem 0;
        justify-content: flex-start;
        z-index: 1001;
        max-height: calc(100vh - 5rem);
        overflow-y: auto;
    }

    .hamburger {
        display: flex;
        min-height: 44px;
        min-width: 44px;
        align-items: center;
        justify-content: center;
        position: relative;
        z-index: 1002;
        cursor: pointer;
        padding: 8px;
        margin-right: 0.5rem; /* 给右边留一点空间 */
    }

    /* 移动设备上调整滚动偏移 */
    section {
        scroll-margin-top: calc(5rem + 1rem); /* 更新的导航栏高度 + 缓冲 */
    }

    .hero-text-wrapper {
        padding: 2rem;
    }

    .hero-badge {
        font-size: 0.8rem;
        padding: 0.4rem 1rem;
        margin-bottom: 1rem;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .title-line {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.25rem;
    }

    .hero-affiliation {
        font-size: 1.1rem;
    }

    .social-link {
        width: 3rem;
        height: 3rem;
    }

    .floating-shape {
        display: none;
    }

    .gradient-orb {
        opacity: 0.2;
    }

    .carousel-glow {
        display: none;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
        gap: 1.5rem;
    }

    .btn {
        width: 100%;
        max-width: 280px;
        text-align: center;
    }

    .section-title {
        font-size: 2rem;
    }

    section {
        padding: 3rem 0;
    }

    .research-grid,
    .teaching-grid {
        grid-template-columns: 1fr;
    }

    .research-tabs {
        grid-template-columns: repeat(2, 1fr);
        gap: 0.5rem;
        padding: 0 0.25rem;
    }

    .research-tab {
        padding: 0.9rem 0.4rem;
        min-height: 90px;
    }

    .tab-icon {
        font-size: 1.5rem;
    }

    .tab-title {
        font-size: 0.85rem;
    }

    .tab-number {
        width: 32px;
        height: 32px;
        font-size: 0.9rem;
        margin-bottom: 0.5rem;
    }

    .tab-icon {
        font-size: 1.75rem;
        margin-bottom: 0.4rem;
    }

    .tab-title {
        font-size: 0.9rem;
        line-height: 1.3;
    }

    .section-intro {
        font-size: 1rem;
        padding: 0 1rem;
        margin-bottom: 2rem;
    }

    .panel-header {
        padding: 1.5rem;
    }

    .panel-header h3 {
        font-size: 1.5rem;
        flex-direction: column;
        gap: 0.5rem;
    }

    .panel-header i {
        font-size: 2rem;
    }

    .panel-content {
        padding: 1.5rem;
    }

    .panel-intro {
        font-size: 1rem;
    }

    .detail-section h4 {
        font-size: 1.2rem;
    }

    .applications-showcase {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .year-navigation {
        gap: 0.4rem;
        padding: 0.75rem 0.25rem;
        flex-wrap: wrap;
        justify-content: flex-start;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: thin;
    }

    .year-nav-btn {
        padding: 0.5rem 0.85rem;
        font-size: 0.8rem;
        min-height: 38px;
        white-space: nowrap;
        flex-shrink: 0;
    }

    .year-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .year-title {
        font-size: 1.8rem;
    }

    .publication-card {
        padding: 1rem;
        margin-bottom: 1.25rem;
    }

    .pub-title {
        font-size: 0.95rem;
        line-height: 1.5;
        margin-bottom: 0.6rem;
    }

    .pub-authors {
        font-size: 0.85rem;
    }

    .pub-venue {
        font-size: 0.8rem;
    }

    .pub-link {
        font-size: 0.75rem;
        padding: 0.35rem 0.7rem;
    }

    .pub-title a {
        word-break: break-word;
    }

    .pub-authors {
        font-size: 0.9rem;
        margin-bottom: 0.5rem;
    }

    .pub-venue {
        font-size: 0.85rem;
        margin-bottom: 0.75rem;
    }

    .pub-links {
        gap: 0.5rem;
        flex-wrap: wrap;
    }

    .pub-link {
        font-size: 0.8rem;
        padding: 0.4rem 0.8rem;
        min-height: 36px;
    }

    .pub-award {
        font-size: 0.85rem;
        padding: 0.5rem;
        margin-bottom: 0.75rem;
    }

    .interests-grid {
        grid-template-columns: 1fr;
    }

    .hero-content {
        gap: 2rem;
    }

    .hero-image {
        max-width: 100%;
    }

    .photo-carousel {
        max-width: 100%;
    }

    .carousel-btn {
        width: 35px;
        height: 35px;
        font-size: 0.9rem;
    }

    .carousel-dots {
        bottom: 15px;
    }

    .dot {
        width: 10px;
        height: 10px;
    }

    .image-placeholder {
        width: 200px;
        height: 200px;
        font-size: 4rem;
    }
}

@media (max-width: 480px) {
    /* Prevent horizontal overflow */
    * {
        max-width: 100%;
    }

    html, body {
        overflow-x: hidden;
        width: 100%;
    }

    .container {
        padding: 0 0.75rem;
        width: 100%;
        overflow-x: hidden;
    }

    /* Improve text readability */
    .section-title {
        font-size: 1.75rem;
        word-wrap: break-word;
    }

    .section-subtitle {
        font-size: 0.95rem;
    }

    .hero-text-wrapper {
        padding: 1.5rem;
        border-radius: 1.5rem;
    }

    .hero-badge {
        font-size: 0.75rem;
        padding: 0.35rem 0.8rem;
        margin-bottom: 0.8rem;
    }

    .hero-title {
        font-size: 2rem;
        margin-bottom: 1rem;
    }

    .title-line {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .hero-affiliation {
        font-size: 1rem;
        margin-bottom: 1.5rem;
    }

    .social-link {
        width: 2.8rem;
        height: 2.8rem;
    }

    .social-link i {
        font-size: 1rem;
    }

    .floating-shape,
    .gradient-orb,
    .carousel-glow {
        display: none;
    }

    .btn {
        padding: 0.75rem 1.5rem;
    }

    .research-content,
    .teaching-card,
    .contact-form {
        padding: 1.5rem;
    }

    .education,
    .awards {
        padding: 1.5rem;
    }

    .year-navigation {
        gap: 0.5rem;
        padding: 0.5rem;
    }

    .year-nav-btn {
        padding: 0.5rem 1rem;
        font-size: 0.85rem;
    }

    .year-section {
        margin-bottom: 3rem;
    }

    .year-title {
        font-size: 1.5rem;
        min-width: 120px;
    }

    .year-icon {
        font-size: 1rem;
    }

    .publication-card {
        padding: 1.25rem;
    }

    .pub-title {
        font-size: 1rem;
    }

    .pub-authors,
    .pub-venue {
        font-size: 0.85rem;
    }

    .pub-links {
        gap: 0.5rem;
    }

    .pub-link {
        font-size: 0.8rem;
        padding: 0.4rem 0.75rem;
    }

    .course-details {
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* 优雅的交叉符号样式 - 参考LaTeX \times */
.cross-symbol {
    position: relative;
    display: inline-block;
    width: 1em;
    height: 1em;
    margin: 0 0.2em;
    vertical-align: middle;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    /* 调试用背景色 - 确保元素可见 */
    /* background: rgba(255, 0, 0, 0.1); */
}

.cross-symbol::before,
.cross-symbol::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0.8em;
    height: 2px;
    background: #ffcb05; /* 直接使用黄色，避免CSS变量问题 */
    border-radius: 1px;
    transform-origin: center;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.cross-symbol::before {
    transform: translate(-50%, -50%) rotate(45deg);
}

.cross-symbol::after {
    transform: translate(-50%, -50%) rotate(-45deg);
}

/* 悬停效果 */
.cross-symbol:hover::before,
.cross-symbol:hover::after {
    background: #00274c; /* Michigan Blue */
    width: 1em;
    box-shadow: 0 2px 4px rgba(0, 39, 76, 0.3);
}

.cross-symbol:hover {
    transform: scale(1.1);
}

/* 导航栏中的交叉符号 */
.nav-lab-desc .cross-symbol::before,
.nav-lab-desc .cross-symbol::after {
    width: 0.7em;
    height: 1.5px;
    background: #ffcb05; /* Maize */
}

/* About部分的交叉符号 */
.about .cross-symbol::before,
.about .cross-symbol::after {
    background: #ffcb05; /* Maize Yellow */
    width: 0.9em;
    height: 2.5px;
}

/* Recent News 竖向时间线布局 */
.news-section {
    margin-top: 3rem;
    padding: 2rem 0;
    background: linear-gradient(135deg, rgba(0, 39, 76, 0.02), rgba(255, 203, 5, 0.02));
    border-radius: 1rem;
}

.news-section h3 {
    font-family: 'Crimson Text', serif;
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-primary);
    position: relative;
}

.news-section h3::after {
    content: '';
    position: absolute;
    bottom: -1rem;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--secondary-color);
    border-radius: 2px;
}

.news-timeline {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 2rem;
    position: relative;
}

/* 时间线主线 */
.news-timeline::before {
    content: '';
    position: absolute;
    left: 0.5rem;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(to bottom, var(--secondary-color), var(--primary-color));
    border-radius: 1px;
}

/* 年份标题 */
.news-year {
    margin: 2rem 0 1.5rem 0;
    padding-left: 0;
}

.news-year h4 {
    color: var(--primary-color);
    font-size: 1.2rem;
    font-weight: 600;
    margin: 0;
    padding: 0.4rem 0.8rem;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    border-radius: 1.5rem;
    display: inline-block;
    box-shadow: var(--shadow);
}

/* 新闻项目 */
.news-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 1rem;
    position: relative;
}

.news-date-inline {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    margin-right: 1rem;
    flex-shrink: 0;
    min-width: 100px;
    width: 100px;
}

.date-month {
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--secondary-color);
    letter-spacing: 0.5px;
}

.date-year {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.news-content {
    flex: 1;
    background: white;
    padding: 0.9rem 1.2rem;
    border-radius: 4px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    /* border-left: 3px solid var(--primary-color); */
    position: relative;
    transition: var(--transition);
    width: 100%;
}

.news-content:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

/* 连接线上的圆点 */
.news-content::before {
    content: '';
    position: absolute;
    left: -1.5rem;
    top: 50%;
    transform: translateY(-50%);
    width: 10px;
    height: 10px;
    background: var(--secondary-color);
    border: 2px solid white;
    border-radius: 50%;
    box-shadow: 0 0 0 2px var(--secondary-color);
    z-index: 1;
}

.news-text {
    flex: 1;
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 0.95rem;
    width: 100%;
}

.news-text strong {
    color: var(--primary-color);
    font-weight: 600;
    font-size: 1.1rem;
}

/* Featured News Styling */
.featured-news {
    background: #ffffff;
    /* border-left: 3px solid var(--primary-color); */
}

/* News Header */
.news-header {
    margin-bottom: 0;
    cursor: pointer;
    user-select: none;
    transition: all 0.3s ease;
}

.news-header:hover {
    background: rgba(0, 39, 76, 0.02);
    border-radius: 4px;
    padding: 0.3rem 0.5rem;
    margin: -0.3rem -0.5rem;
}

.news-title-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.news-title-text {
    flex: 1;
    text-align: left;
    min-width: 0;
}

.news-header strong {
    font-size: 1rem;
    color: var(--primary-color);
    font-weight: 600;
    letter-spacing: -0.01em;
    white-space: normal;
}

.news-toggle {
    flex-shrink: 0;
    padding: 0.3rem 0.8rem;
    border: 1px solid var(--primary-color);
    background: transparent;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    color: var(--primary-color);
    font-size: 0.8rem;
    font-weight: 500;
    font-family: 'Source Sans Pro', sans-serif;
}

.news-toggle:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.news-toggle .toggle-text {
    transition: opacity 0.3s ease;
}

.news-header.collapsed .news-toggle .toggle-text::after {
    content: ' ▼';
    font-size: 0.7rem;
    opacity: 0.6;
    margin-left: 0.3rem;
}

.news-header:not(.collapsed) .news-toggle .toggle-text::after {
    content: ' ▲';
    font-size: 0.7rem;
    opacity: 0.6;
    margin-left: 0.3rem;
}

.news-details {
    max-height: 5000px;
    overflow: hidden;
    transition: max-height 0.5s ease, opacity 0.3s ease;
    opacity: 1;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid #e5e7eb;
}

.news-header.collapsed + .news-details {
    max-height: 0;
    opacity: 0;
    margin-top: 0;
    padding-top: 0;
    border-top: none;
}

/* Badges */
.news-badges {
    display: flex;
    gap: 0.5rem;
    flex-wrap: nowrap;
    flex-shrink: 0;
}

.badge {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: 3px;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    text-transform: uppercase;
    font-family: 'Source Sans Pro', sans-serif;
    white-space: nowrap;
}

.badge-spotlight {
    background: #fef3c7;
    color: #92400e;
    border: 1px solid #fde68a;
}

.badge-poster {
    background: #dbeafe;
    color: #1e40af;
    border: 1px solid #93c5fd;
}

/* Paper Sections */
.paper-section {
    margin-bottom: 1.5rem;
}

.paper-section:last-child {
    margin-bottom: 0;
}

.paper-category {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 1rem;
    padding: 0.6rem 1rem;
    background: #f8fafc;
    border-radius: 4px;
    /* border-left: 3px solid var(--primary-color); */
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-family: 'Source Sans Pro', sans-serif;
}

.category-note {
    font-size: 0.85rem;
    color: var(--secondary-color);
    font-weight: 600;
    margin-left: 0.3rem;
}

/* Paper Lists */
.paper-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.paper-item {
    background: white;
    padding: 1.25rem;
    border-radius: 4px;
    border: 1px solid #e5e7eb;
    transition: all 0.3s ease;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04);
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.paper-item:hover {
    border-color: var(--primary-color);
    box-shadow: 0 2px 8px rgba(0, 39, 76, 0.1);
}

.spotlight-list .paper-item {
    border-left: 3px solid #f59e0b;
}

.poster-list .paper-item {
    border-left: 3px solid #3b82f6;
}

.paper-title {
    margin-bottom: 0;
    flex: 1;
    min-width: 0;
}

.paper-title a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    line-height: 1.6;
    transition: color 0.3s ease;
    font-size: 0.95rem;
    display: inline;
}

.paper-title a:hover {
    color: var(--primary-color);
}

.paper-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-top: 0;
    flex-shrink: 0;
}

.paper-link {
    display: inline-block;
    padding: 0.35rem 0.9rem;
    background: #f1f5f9;
    color: var(--primary-color);
    text-decoration: none;
    border-radius: 3px;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
    font-family: 'Source Sans Pro', sans-serif;
}

.paper-link:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    text-decoration: none;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .news-section {
        padding: 1.5rem 0;
        margin-top: 2rem;
    }

    .news-section h3 {
        font-size: 1.75rem;
        margin-bottom: 2rem;
        padding: 0 1rem;
    }

    .news-timeline {
        padding: 0 0.5rem;
        max-width: 100%;
    }

    .news-timeline::before {
        left: 0.25rem;
    }

    .news-year {
        padding-left: 0;
        margin: 1.5rem 0 1rem;
    }

    .news-year h4 {
        font-size: 1rem;
        padding: 0.3rem 0.6rem;
    }

    .news-item {
        margin-bottom: 1rem;
        padding-left: 1.5rem;
    }

    .news-content {
        padding: 1rem;
        margin-left: 0.5rem;
    }

    .news-content::before {
        left: -1.5rem;
        width: 10px;
        height: 10px;
    }

    .news-text {
        font-size: 0.9rem;
        line-height: 1.6;
    }

    .news-text strong {
        font-size: 1rem;
    }
    
    .news-toggle {
        padding: 0.4rem 0.8rem;
        font-size: 0.8rem;
        min-height: 36px;
        min-width: 80px;
    }

    .news-header strong {
        font-size: 0.95rem;
    }
    
    .news-date-inline {
        margin-right: 0.75rem;
        min-width: 75px;
        width: 75px;
        flex-shrink: 0;
    }
    
    .date-month {
        font-size: 0.85rem;
    }

    .date-year {
        font-size: 0.8rem;
    }

    .badge {
        font-size: 0.7rem;
        padding: 0.2rem 0.5rem;
    }
    
    .news-title-row {
        gap: 0.5rem;
        flex-wrap: wrap;
        align-items: flex-start;
    }
    
    .news-badges {
        gap: 0.4rem;
        flex-wrap: wrap;
    }

    .news-title-text {
        font-size: 0.9rem;
        line-height: 1.5;
    }

    .paper-category {
        font-size: 1rem;
        padding: 0.5rem 0.75rem;
        margin-bottom: 1rem;
    }

    .paper-item {
        padding: 1rem;
        margin-bottom: 0.75rem;
    }

    .paper-title {
        font-size: 0.95rem;
        line-height: 1.5;
        margin-bottom: 0.5rem;
    }

    .paper-title a {
        word-break: break-word;
    }

    .paper-links {
        gap: 0.5rem;
        margin-left: 0;
        margin-top: 0.5rem;
        flex-wrap: wrap;
    }
    
    .paper-link {
        font-size: 0.75rem;
        padding: 0.35rem 0.7rem;
        min-height: 32px;
    }
}

/* 联系页面的交叉符号 */
.contact .cross-symbol::before,
.contact .cross-symbol::after {
    background: #ffcb05; /* Maize */
    width: 0.8em;
    height: 2px;
}

/* Contact页面布局优化 */
.contact .contact-content {
    display: flex;
    justify-content: center;
}

.contact .contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    width: 100%;
}

.contact .contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    padding: 2rem;
    background: white;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 4px solid var(--secondary-color);
}

.contact .contact-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.contact .contact-item i {
    font-size: 2rem;
    color: var(--primary-color);
    flex-shrink: 0;
    margin-top: 0.25rem;
}

.contact .contact-item h3 {
    margin-bottom: 0.75rem;
    color: var(--primary-color);
    font-size: 1.25rem;
    font-weight: 600;
}

.contact .contact-item p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .contact .contact-info {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .contact .contact-item {
        padding: 1.5rem;
    }

    .contact .contact-item i {
        font-size: 1.5rem;
    }
}

/* People页面样式 */
.people {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    min-height: 100vh;
    padding: 6rem 0 4rem;
}

.section-subtitle {
    text-align: center;
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-top: -1rem;
    margin-bottom: 4rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* Team Section Spacing */
.team-section {
    margin-bottom: 5rem;
}

/* PI Section Styles */
.pi-section {
    max-width: 60%;
    margin: 0 auto 5rem;
}

.pi-card {
    background: white;
    border-radius: 1.5rem;
    padding: 1.5rem;
    box-shadow: 0 10px 40px rgba(0, 39, 76, 0.1);
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 1.5rem;
    align-items: start;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.pi-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 50px rgba(0, 39, 76, 0.15);
    border-color: var(--secondary-color);
}

.pi-photo {
    position: relative;
    border-radius: 1rem;
    overflow: hidden;
    box-shadow: 0 8px 30px rgba(0, 39, 76, 0.2);
    aspect-ratio: 1 / 1;
    width: 100%;
}

.pi-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.3s ease;
}

.pi-card:hover .pi-photo img {
    transform: scale(1.05);
}

.pi-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(0, 39, 76, 0.9), transparent);
    padding: 2rem 1rem 1rem;
    transform: translateY(100%);
    transition: transform 0.3s ease;
}

.pi-card:hover .pi-overlay {
    transform: translateY(0);
}

.pi-social {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.pi-social a {
    width: 40px;
    height: 40px;
    background: rgba(255, 203, 5, 0.9);
    color: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all 0.3s ease;
}

.pi-social a:hover {
    background: #FFCB05;
    transform: translateY(-3px);
}

.pi-info {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.pi-name {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--primary-color);
    margin: 0;
}

.pi-title {
    font-size: 1.1rem;
    color: var(--secondary-color);
    font-weight: 600;
    margin: 0;
}

.pi-department,
.pi-affiliation {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin: 0;
}

.pi-bio {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 2px solid #e2e8f0;
}

.pi-bio p {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-primary);
    margin: 0;
}

.pi-contact {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    margin-top: 0.5rem;
    padding: 0.75rem;
    background: linear-gradient(135deg, #f8fafc, #e2e8f0);
    border-radius: 0.5rem;
    border-left: 3px solid var(--primary-color);
}

.pi-contact span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.pi-contact i {
    color: var(--primary-color);
    width: 18px;
}

/* Team Grid Styles */
.team-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 1.5rem;
    margin-top: 2rem;
}

.member-card {
    background: white;
    border-radius: 1rem;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0, 39, 76, 0.08);
    transition: all 0.3s ease;
    border: 2px solid transparent;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.member-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 35px rgba(0, 39, 76, 0.15);
    border-color: var(--secondary-color);
}

.member-photo {
    position: relative;
    overflow: hidden;
    aspect-ratio: 1 / 1;
    width: 100%;
}

.member-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.member-card:hover .member-photo img {
    transform: scale(1.1);
}

.member-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0, 39, 76, 0.95), transparent);
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding: 1.5rem;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.member-card:hover .member-overlay {
    opacity: 1;
}

.member-social {
    display: flex;
    gap: 0.8rem;
}

.member-social a {
    width: 36px;
    height: 36px;
    background: rgba(255, 203, 5, 0.9);
    color: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all 0.3s ease;
}

.member-social a:hover {
    background: #FFCB05;
    transform: translateY(-3px) scale(1.1);
}

.member-info {
    padding: 1rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.member-name {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: 0 0 0.2rem;
}

.member-position {
    font-size: 0.95rem;
    color: var(--secondary-color);
    font-weight: 600;
    margin: 0 0 0.5rem;
}

.member-research,
.member-education,
.member-year {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin: 0.2rem 0;
    display: flex;
    align-items: center;
    gap: 0.4rem;
}

.member-research i,
.member-education i,
.member-year i {
    color: var(--primary-color);
    width: 16px;
}

.member-coadvisor {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin: 0.3rem 0;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.3rem 0.5rem;
    background: linear-gradient(135deg, #f8fafc, #e2e8f0);
    border-radius: 0.3rem;
    border-left: 3px solid var(--secondary-color);
}

.member-coadvisor i {
    color: var(--secondary-color);
    width: 16px;
    flex-shrink: 0;
}

.member-coadvisor a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border-bottom: 1px solid transparent;
}

.member-coadvisor a:hover {
    color: var(--secondary-color);
    border-bottom-color: var(--secondary-color);
}

/* Join Us Banner */
.join-us-banner {
    background: linear-gradient(135deg, var(--primary-color), #1e40af);
    border-radius: 1.5rem;
    padding: 3rem;
    text-align: center;
    box-shadow: 0 10px 40px rgba(0, 39, 76, 0.2);
    margin: 4rem 0;
    position: relative;
    overflow: hidden;
}

.join-us-banner::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 300px;
    height: 300px;
    background: rgba(255, 203, 5, 0.1);
    border-radius: 50%;
}

.join-us-banner::after {
    content: '';
    position: absolute;
    bottom: -50%;
    left: -10%;
    width: 300px;
    height: 300px;
    background: rgba(255, 203, 5, 0.1);
    border-radius: 50%;
}

.join-us-content {
    position: relative;
    z-index: 1;
}

.join-us-content h3 {
    color: white;
    font-size: 2rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.8rem;
}

.join-us-content h3 i {
    color: #FFCB05;
}

.join-us-content p {
    color: rgba(255, 255, 255, 0.95);
    font-size: 1.1rem;
    margin-bottom: 2rem;
    line-height: 1.7;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.join-team-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
    background: #FFCB05;
    color: var(--primary-color);
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 20px rgba(255, 203, 5, 0.3);
}

.join-team-btn:hover {
    background: white;
    transform: translateY(-3px);
    box-shadow: 0 6px 30px rgba(255, 203, 5, 0.5);
}

.join-team-btn i {
    transition: transform 0.3s ease;
}

.join-team-btn:hover i {
    transform: translateX(5px);
}

/* Alumni Section */
.alumni-intro {
    text-align: center;
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.alumni-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.alumni-card {
    background: linear-gradient(135deg, #f8fafc, #ffffff);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: 0 2px 15px rgba(0, 39, 76, 0.06);
    transition: all 0.3s ease;
    border: 2px solid transparent;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.alumni-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 39, 76, 0.12);
    border-color: var(--secondary-color);
    background: white;
}

.alumni-photo {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    overflow: hidden;
    margin-bottom: 1rem;
    box-shadow: 0 4px 15px rgba(0, 39, 76, 0.15);
    border: 3px solid white;
    position: relative;
}

.alumni-card:hover .alumni-photo {
    border-color: var(--secondary-color);
    transform: scale(1.05);
    transition: all 0.3s ease;
}

.alumni-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.alumni-info {
    text-align: center;
}

.alumni-name {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: 0 0 0.8rem;
}

.alumni-degree,
.alumni-current,
.alumni-institution,
.alumni-year {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin: 0.3rem 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
}

.alumni-current {
    color: var(--secondary-color);
    font-weight: 600;
}

.alumni-degree i,
.alumni-current i,
.alumni-institution i,
.alumni-year i {
    color: var(--primary-color);
    font-size: 0.8rem;
}

.subsection-title {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 2.5rem;
    text-align: center;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.8rem;
}

.subsection-title::after {
    content: '';
    position: absolute;
    bottom: -1rem;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.subsection-title i {
    color: var(--secondary-color);
    font-size: 1.8rem;
}

.mentorship-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.student-card {
    background: white;
    border-radius: 1rem;
    padding: 1.2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    border-left: 4px solid var(--secondary-color);
    overflow: hidden;
}

.student-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.student-card::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 100px;
    height: 100px;
    background: linear-gradient(135deg, var(--secondary-color)20, transparent);
    border-radius: 0 1rem 0 100%;
}

.student-info {
    position: relative;
    z-index: 2;
}

.student-name {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.student-details {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.student-details p {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin: 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.student-details i {
    color: var(--primary-color);
    width: 16px;
    text-align: center;
    flex-shrink: 0;
}

.university {
    font-weight: 500;
    color: var(--text-primary) !important;
}

.degree {
    color: var(--secondary-color) !important;
    font-weight: 500;
}

.timeline {
    font-style: italic;
}

.mentorship-journey {
    color: var(--text-primary) !important;
    font-weight: 500;
    background: linear-gradient(135deg, #f8fafc, #e2e8f0);
    padding: 0.25rem 0.4rem;
    border-radius: 0.4rem;
    border-left: 3px solid var(--primary-color);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    position: relative;
    font-size: 0.85rem;
    line-height: 1.3;
}

.mentorship-journey i {
    color: var(--primary-color) !important;
    margin-right: 0.4rem;
    font-size: 0.85rem;
}

.mentorship-info {
    font-size: 0.9rem;
    opacity: 0.8;
}

.student-number {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 35px;
    height: 35px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 1rem;
    z-index: 3;
}

/* People页面响应式设计 */
@media (max-width: 1400px) {
    .pi-card {
        grid-template-columns: 270px 1fr;
    }
    
    .team-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 1.5rem;
    }
}

@media (max-width: 992px) {
    .pi-section {
        max-width: 75%;
    }
    
    .pi-card {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .pi-photo {
        max-width: 350px;
        margin: 0 auto;
    }

    .team-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 1.5rem;
    }
}

@media (max-width: 768px) {
    .people {
        padding: 5rem 0 3rem;
    }

    .section-subtitle {
        font-size: 1rem;
        margin-bottom: 3rem;
    }

    .subsection-title {
        font-size: 1.6rem;
    }

    .subsection-title i {
        font-size: 1.5rem;
    }

    .pi-section {
        max-width: 100%;
    }

    .pi-card {
        padding: 1.5rem;
    }

    .pi-name {
        font-size: 1.5rem;
    }

    .pi-title {
        font-size: 1rem;
    }

    .team-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .alumni-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 1.5rem;
    }

    .join-us-banner {
        padding: 2rem;
    }

    .join-us-content h3 {
        font-size: 1.6rem;
    }

    .join-us-content p {
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .people {
        padding: 4rem 0 2rem;
    }

    .subsection-title {
        font-size: 1.4rem;
        flex-direction: column;
        gap: 0.5rem;
    }

    .pi-card {
        padding: 1.5rem;
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .pi-photo {
        max-width: 200px;
        margin: 0 auto;
    }

    .pi-info {
        text-align: center;
    }

    .pi-name {
        font-size: 1.4rem;
    }

    .pi-title {
        font-size: 1rem;
    }

    .pi-contact {
        font-size: 0.9rem;
    }

    .team-grid,
    .alumni-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }

    .member-card {
        border-radius: 0.75rem;
    }

    .member-info {
        padding: 1rem;
    }

    .member-name {
        font-size: 1rem;
    }

    .member-position,
    .member-education,
    .member-research,
    .member-year {
        font-size: 0.85rem;
    }

    .join-us-banner {
        padding: 1.5rem;
        border-radius: 1rem;
    }

    .join-us-content h3 {
        font-size: 1.4rem;
        flex-direction: column;
    }

    .join-team-btn {
        padding: 0.8rem 2rem;
        font-size: 1rem;
    }

    .alumni-photo {
        width: 100px;
        height: 100px;
    }
}

/* Opening页面样式 */
.opening {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    min-height: 100vh;
}

/* 招生横幅样式 */
.recruitment-banner {
    background: linear-gradient(135deg, #ffffff, #f8fafc);
    color: var(--text-primary);
    padding: 3rem 2rem;
    border-radius: 1.5rem;
    text-align: center;
    margin-bottom: 4rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    border: 1px solid #e2e8f0;
}

.recruitment-banner h3 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    color: var(--primary-color);
    font-weight: 700;
}

.recruitment-banner h3 i {
    color: var(--secondary-color);
    font-size: 2.2rem;
}

.recruitment-banner > p {
    font-size: 1.3rem;
    margin-bottom: 2.5rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.positions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2.5rem 0;
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
    align-items: stretch;
}

.position-card {
    background: white;
    color: var(--text-primary);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
    border: 1px solid #f1f5f9;
    border-left: 4px solid var(--secondary-color);
    display: flex;
    flex-direction: column;
    height: 100%;
    text-align: center;
}

.position-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    border-color: #e2e8f0;
}

.position-card.phd {
    border-top-color: #10b981;
}

.position-card.postdoc {
    border-top-color: #f59e0b;
}

.position-card.ra {
    border-top-color: #8b5cf6;
}

.position-card h4 {
    color: var(--primary-color);
    font-size: 1.4rem;
    margin-bottom: 1rem;
    min-height: 3.5rem;
    line-height: 1.3;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.position-card h4 i {
    font-size: 1.6rem;
    margin-bottom: 0.5rem;
}

.position-card.phd h4 i {
    color: #10b981;
}

.position-card.postdoc h4 i {
    color: #f59e0b;
}

.position-card.ra h4 i {
    color: #8b5cf6;
}

.position-card > p {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 1.5rem;
}

.position-card ul {
    list-style: none;
    padding: 0;
    text-align: center;
    flex-grow: 1;
    margin: 0;
}

.position-card li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    padding-left: 1.2rem;
    position: relative;
    line-height: 1.5;
}

.position-card li::before {
    content: '✓';
    color: var(--secondary-color);
    position: absolute;
    left: 0;
    font-weight: bold;
}

.apply-now {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid #e2e8f0;
}

.apply-now p {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
    font-weight: 600;
}

.apply-button {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    background: linear-gradient(135deg, var(--primary-color), #1e40af);
    color: white;
    padding: 1.2rem 2.5rem;
    border-radius: 0.75rem;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.2rem;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(0, 39, 76, 0.2);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.apply-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 39, 76, 0.3);
    color: white;
    background: linear-gradient(135deg, #1e40af, var(--primary-color));
}

.opening-section {
    margin-bottom: 3rem;
}

.opening-intro {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    text-align: center;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.research-areas {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.research-area {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary-color);
    transition: var(--transition);
}

.research-area:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.research-area h4 {
    color: var(--primary-color);
    font-size: 1.3rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.research-area h4 i {
    color: var(--secondary-color);
}

.research-area p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.research-area ul {
    list-style: none;
    padding: 0;
}

.research-area li {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    padding-left: 1rem;
    position: relative;
}

.research-area li::before {
    content: '▸';
    color: var(--secondary-color);
    position: absolute;
    left: 0;
    font-weight: bold;
}

.call-to-action {
    background: linear-gradient(135deg, var(--primary-color), #1e40af);
    color: white;
    padding: 2rem;
    border-radius: 1rem;
    text-align: center;
    margin: 2rem 0;
}

.call-to-action p {
    font-size: 1.2rem;
    margin: 0;
    line-height: 1.6;
}

.umich-intro {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    text-align: center;
}

.umich-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.highlight-card {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--secondary-color);
}

.highlight-card h4 {
    color: var(--primary-color);
    font-size: 1.2rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.highlight-card h4 i {
    color: var(--secondary-color);
}

.highlight-card ul {
    list-style: none;
    padding: 0;
}

.highlight-card li {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    padding-left: 1rem;
    position: relative;
    line-height: 1.6;
}

.highlight-card li::before {
    content: '✓';
    color: var(--secondary-color);
    position: absolute;
    left: 0;
    font-weight: bold;
}

.requirements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.requirement-card {
    background: white;
    padding: 1.5rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

.requirement-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.requirement-card h4 {
    color: var(--primary-color);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.requirement-card h4 i {
    color: var(--secondary-color);
}

.requirement-card p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0;
}

.support-categories {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.support-category {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--secondary-color);
}

.support-category h4 {
    color: var(--primary-color);
    font-size: 1.2rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.support-category h4 i {
    color: var(--secondary-color);
}

.support-category ul {
    list-style: none;
    padding: 0;
}

.support-category li {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    padding-left: 1rem;
    position: relative;
    line-height: 1.6;
}

.support-category li::before {
    content: '●';
    color: var(--secondary-color);
    position: absolute;
    left: 0;
}

.mentorship-content {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
}

.mentorship-intro {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.training-paths {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.training-path {
    background: linear-gradient(135deg, #f8fafc, #e2e8f0);
    padding: 1.5rem;
    border-radius: 0.75rem;
    border-left: 4px solid var(--primary-color);
}

.training-path h4 {
    color: var(--primary-color);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.training-path h4 i {
    color: var(--secondary-color);
}

.training-path p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0;
}

.mentorship-conclusion {
    font-size: 1.1rem;
    color: var(--primary-color);
    text-align: center;
    margin-top: 2rem;
    font-weight: 500;
}

.opening-cta {
    background: linear-gradient(135deg, var(--secondary-color), #f59e0b);
    color: white;
    padding: 3rem 2rem;
    border-radius: 1rem;
    text-align: center;
    margin-top: 3rem;
}

.opening-cta h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.opening-cta p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: white;
    color: var(--primary-color);
    padding: 1rem 2rem;
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
    color: var(--primary-color);
}

/* Opening页面响应式设计 */
@media (max-width: 768px) {
    .recruitment-banner {
        padding: 2rem 1rem;
        margin-bottom: 3rem;
    }

    .recruitment-banner h3 {
        font-size: 2rem;
        flex-direction: column;
        gap: 0.5rem;
    }

    .recruitment-banner > p {
        font-size: 1.1rem;
    }

    .positions-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .position-card {
        padding: 1.5rem;
    }

    .apply-button {
        padding: 1rem 2rem;
        font-size: 1.1rem;
    }

    .research-areas {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .umich-highlights {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .requirements-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .support-categories {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .training-paths {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .opening-cta {
        padding: 2rem 1rem;
    }

    .opening-cta h3 {
        font-size: 1.5rem;
    }
}

/* 页面级别的样式 */
.page-section {
    background-image: url('./fig/background_light.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    padding-top: 120px;
    min-height: 100vh;
}

/* 导航栏活跃状态 */
.nav-link.active {
    color: var(--secondary-color) !important;
    font-weight: 600;
}

/* 联系页面额外样式 */
.social-section {
    margin-top: 4rem;
    text-align: center;
}

.social-section h3 {
    margin-bottom: 2rem;
    color: var(--primary-color);
    font-size: 1.5rem;
}

.social-links-large {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.social-link-large {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    padding: 1.5rem;
    background: white;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
    min-width: 120px;
}

.social-link-large:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
    color: var(--primary-color);
}

.social-link-large i {
    font-size: 2rem;
    color: var(--primary-color);
}

.social-link-large span {
    font-weight: 600;
    font-size: 0.9rem;
}

/* 实验室信息样式 */
.lab-info {
    margin-top: 4rem;
    padding: 3rem;
    background: linear-gradient(135deg, rgba(0, 39, 76, 0.02), rgba(255, 203, 5, 0.02));
    border-radius: 1rem;
}

.lab-info h3 {
    margin-bottom: 2rem;
    color: var(--primary-color);
    font-size: 1.5rem;
    text-align: center;
}

.lab-description p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 2rem;
    text-align: center;
}

.lab-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.lab-highlight {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: white;
    border-radius: 0.75rem;
    box-shadow: var(--shadow);
}

.lab-highlight i {
    font-size: 2rem;
    color: var(--primary-color);
    flex-shrink: 0;
}

.lab-highlight h4 {
    margin-bottom: 0.5rem;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.lab-highlight p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 0;
}

/* 教学哲学样式 */
.teaching-philosophy {
    margin-top: 4rem;
    padding: 3rem;
    background: linear-gradient(135deg, rgba(0, 39, 76, 0.02), rgba(255, 203, 5, 0.02));
    border-radius: 1rem;
}

.teaching-philosophy h3 {
    margin-bottom: 2rem;
    color: var(--primary-color);
    font-size: 1.5rem;
    text-align: center;
}

.philosophy-content p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 2rem;
    text-align: center;
}

.philosophy-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.philosophy-highlights .highlight-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    background: white;
    border-radius: 0.75rem;
    box-shadow: var(--shadow);
}

.philosophy-highlights .highlight-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-top: 0.25rem;
    flex-shrink: 0;
}

.philosophy-highlights .highlight-item h4 {
    margin-bottom: 0.5rem;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.philosophy-highlights .highlight-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 0;
    text-align: left;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .social-links-large {
        gap: 1rem;
    }

    .social-link-large {
        min-width: 100px;
        padding: 1rem;
    }

    .lab-highlights,
    .philosophy-highlights {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .lab-info,
    .teaching-philosophy {
        padding: 2rem;
    }
}

/* 响应式调整 */
@media (max-width: 768px) {
    .cross-symbol {
        width: 0.9em;
        height: 0.9em;
        margin: 0 0.15em;
    }

    .cross-symbol::before,
    .cross-symbol::after {
        width: 0.7em;
        height: 1.5px;
    }
}

/* 移动设备触摸优化 */
@media (max-width: 768px) {
    /* 移动设备导航栏简化：只显示汉堡菜单 */

    /* 改进触摸目标大小 */
    .nav-link,
    .btn,
    .social-link,
    .hamburger {
        min-height: 44px;
        min-width: 44px;
    }

    /* 防止文本选择干扰触摸 */
    .nav-menu,
    .hamburger,
    .btn {
        -webkit-user-select: none;
        -moz-user-select: none;
        -ms-user-select: none;
        user-select: none;
        -webkit-touch-callout: none;
    }

    /* 改进滚动性能 */
    body {
        -webkit-overflow-scrolling: touch;
    }

    /* 防止双击缩放 */
    .nav-link,
    .btn,
    .hamburger {
        touch-action: manipulation;
    }
}

/* iPhone 15 Pro Max 和类似大屏手机优化 */
@media (max-width: 430px) {
    .container {
        padding: 0 0.5rem;
    }

    /* iPhone导航栏进一步调整 */
    .unified-navbar {
        min-height: 5.5rem;
        padding: 1rem 0;
    }

    .unified-container {
        justify-content: flex-end; /* iPhone上也只显示汉堡菜单 */
    }

    /* iPhone上也隐藏logo */
    .lab-logo,
    .umich-logo,
    .nav-lab-info {
        display: none !important;
    }

    .nav-menu {
        top: 5.5rem; /* 匹配iPhone导航栏高度 */
        max-height: calc(100vh - 5.5rem);
    }

    .hero {
        padding-top: 8rem; /* iPhone需要更多空间 */
        padding-left: 0.5rem;
        padding-right: 0.5rem;
        background: var(--umich-gradient-mobile); /* iPhone也使用纯蓝色渐变 */
    }

    .hero-container {
        padding: 0 0.5rem;
    }

    .hero-title {
        font-size: 1.6rem;
        line-height: 1.1;
        margin-bottom: 0.5rem;
    }

    .hero-subtitle {
        font-size: 0.95rem;
        margin-bottom: 0.5rem;
    }

    .hero-affiliation {
        font-size: 0.85rem;
        line-height: 1.3;
        margin-bottom: 1rem;
    }

    .hero-description {
        font-size: 0.85rem;
        line-height: 1.4;
        margin-bottom: 1.5rem;
    }

    .hero-description p {
        margin-bottom: 0.8rem;
    }

    .btn {
        font-size: 0.85rem;
        padding: 0.7rem 1.2rem;
        max-width: 220px;
        min-height: 44px;
    }

    .unified-navbar {
        padding: 0.2rem 0;
    }

    .unified-container {
        padding: 0 0.5rem 0 0;
    }

    .nav-menu {
        top: 3.5rem;
        padding: 1rem 0;
        z-index: 999;
    }

    .hero-buttons {
        gap: 0.8rem;
        margin-bottom: 1.2rem;
    }

    .social-links {
        gap: 0.8rem;
    }

    .social-link {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }

    /* 确保内容不超出屏幕 */
    .hero {
        min-height: 100vh;
        padding: 1rem 0;
        padding-top: max(1rem, env(safe-area-inset-top));
    }

    .hero-content {
        padding: 0.5rem 0;
    }

    /* iPhone 15 Pro Max 导航栏优化 */
    .unified-navbar {
        padding-top: max(0.2rem, env(safe-area-inset-top));
        min-height: 3.5rem;
    }

    /* 调整iPhone 15 Pro Max的页面内容间距 */
    .page-section {
        padding-top: 4.5rem;
    }

    .hero {
        padding-top: 4.5rem;
    }

    /* 确保按钮在安全区域内 */
    .hero-buttons {
        margin-bottom: max(1.2rem, env(safe-area-inset-bottom));
    }
}

/* 超小屏幕优化 */
@media (max-width: 480px) {
    .container {
        padding: 0 0.75rem;
    }

    .unified-container {
        justify-content: flex-end; /* 480px以下也只显示汉堡菜单 */
    }

    /* 480px以下也隐藏logo */
    .lab-logo,
    .umich-logo,
    .nav-lab-info {
        display: none !important;
    }

    .hero {
        background: var(--umich-gradient-mobile); /* 480px以下也使用纯蓝色渐变 */
    }

    .hero-title {
        font-size: 1.8rem;
        line-height: 1.2;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .hero-description {
        font-size: 0.9rem;
        line-height: 1.5;
    }

    .hero-description p {
        margin-bottom: 1rem;
    }

    .btn {
        font-size: 0.9rem;
        padding: 0.8rem 1.5rem;
        max-width: 250px;
    }

    .unified-navbar {
        padding: 0.25rem 0;
        min-height: 3.5rem;
    }

    /* 调整480px断点的页面内容间距 */
    .page-section {
        padding-top: 4.5rem;
    }

    .hero {
        padding-top: 4.5rem;
    }

    .unified-container {
        padding: 0 0.75rem 0 0;
    }

    .nav-menu {
        top: 3.5rem;
        padding: 1.5rem 0;
        z-index: 999;
    }

    .hero-buttons {
        gap: 1rem;
        margin-bottom: 1.5rem;
    }
}

/* Join the Lab Page Styles */
.join-lab {
    background-image: url('./fig/background_light.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-color: var(--surface);
    min-height: calc(100vh - 400px);
    padding: 6rem 0 4rem;
}

@media (max-width: 768px) {
    .join-lab {
        background-attachment: scroll;
    }
}

.join-section {
    margin-bottom: 4rem;
}

.join-card {
    background: white;
    border-radius: 0.5rem;
    padding: 3.5rem;
    box-shadow: 0 2px 8px rgba(0, 39, 76, 0.06);
    border: 1px solid rgba(0, 39, 76, 0.08);
    transition: all 0.3s ease;
    max-width: 900px;
    margin: 0 auto;
}

.join-card:hover {
    box-shadow: 0 4px 16px rgba(0, 39, 76, 0.12);
    border-color: rgba(0, 39, 76, 0.15);
}

.join-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--primary-color);
    margin: 0 0 2rem 0;
    padding-bottom: 1rem;
    border-bottom: 3px solid var(--primary-color);
    letter-spacing: -0.02em;
}

.join-content {
    max-width: 100%;
}

.join-intro {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-primary);
    margin-bottom: 2rem;
}

.join-subtitle {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: 2rem 0 1rem 0;
    letter-spacing: -0.01em;
}

.join-content p {
    font-size: 1.05rem;
    line-height: 1.75;
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
}

.join-content strong {
    color: var(--primary-color);
    font-weight: 600;
}

.join-requirements {
    list-style: decimal;
    padding-left: 1.5rem;
    margin: 1.5rem 0;
}

.join-requirements li {
    padding: 0.75rem 0;
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--text-primary);
}

.join-programs {
    list-style: none;
    padding: 0;
    margin: 1.5rem 0;
}

.join-programs li {
    padding: 0.75rem 0;
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--text-primary);
    border-bottom: 1px solid rgba(0, 39, 76, 0.08);
    transition: all 0.2s ease;
}

.join-programs li:last-child {
    border-bottom: none;
}

.join-programs li:hover {
    padding-left: 0.5rem;
}

.join-requirements a,
.join-programs a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
    border-bottom: 1px solid transparent;
}

.join-requirements a:hover,
.join-programs a:hover {
    color: var(--secondary-color);
    border-bottom-color: var(--secondary-color);
}

.join-highlight {
    background: rgba(255, 203, 5, 0.08);
    border-left: 4px solid var(--secondary-color);
    padding: 1.5rem;
    border-radius: 0.25rem;
    margin: 2rem 0;
}

.join-highlight p {
    margin: 0;
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--text-primary);
}

.join-highlight strong {
    color: var(--primary-color);
    font-weight: 600;
}

.join-action {
    text-align: center;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(0, 39, 76, 0.1);
}

.join-action .btn {
    padding: 0.875rem 2.25rem;
    font-size: 1.05rem;
    font-weight: 600;
    letter-spacing: 0.01em;
}

/* Responsive styles for Join page */
@media (max-width: 768px) {
    .join-lab {
        padding: 5rem 0 3rem;
    }

    .join-card {
        padding: 1.75rem 1.25rem;
        margin: 0 0.75rem;
    }

    .join-title {
        font-size: 1.35rem;
        margin-bottom: 0.9rem;
    }

    .join-intro {
        font-size: 0.95rem;
    }

    .join-content p {
        font-size: 0.9rem;
    }

    .join-requirements li,
    .join-programs li {
        font-size: 0.9rem;
    }

    .join-intro {
        font-size: 1rem;
        line-height: 1.6;
        margin-bottom: 1.5rem;
    }

    .join-content p {
        font-size: 0.95rem;
        line-height: 1.6;
        margin-bottom: 1rem;
    }

    .join-subtitle {
        font-size: 1.1rem;
        margin: 1.5rem 0 1rem;
    }

    .join-requirements,
    .join-programs {
        margin: 1rem 0;
    }

    .join-requirements li,
    .join-programs li {
        font-size: 0.95rem;
        padding: 0.5rem 0;
        line-height: 1.6;
    }

    .join-requirements a,
    .join-programs a {
        word-break: break-word;
    }

    .join-highlight {
        padding: 1.25rem;
        margin: 1.5rem 0;
        border-radius: 0.5rem;
    }

    .join-highlight p {
        font-size: 0.95rem;
        line-height: 1.6;
    }

    .join-action {
        margin-top: 1.5rem;
    }

    .join-action .btn {
        width: 100%;
        max-width: 300px;
        padding: 0.85rem 1.5rem;
        font-size: 1rem;
        min-height: 44px;
    }
}

@media (max-width: 480px) {
    .join-card {
        padding: 2rem 1.5rem;
        margin: 0 0.5rem;
    }

    .join-title {
        font-size: 1.35rem;
        padding-bottom: 0.75rem;
    }

    .join-intro {
        font-size: 1rem;
    }

    .join-content p {
        font-size: 0.95rem;
    }

    .join-requirements li,
    .join-programs li {
        font-size: 0.95rem;
    }

    .join-highlight {
        padding: 1.25rem;
    }

    .join-highlight p {
        font-size: 1rem;
    }

    .join-action {
        margin-top: 2rem;
        padding-top: 1.5rem;
    }

    .join-action .btn {
        padding: 0.75rem 1.75rem;
        font-size: 1rem;
    }
}