/* 全局变量和重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6b1d2b;          /* 勃艮第红 */
    --primary-light: #8b2c42;          /* 浅勃艮第红 */
    --primary-dark: #4a1220;           /* 深勃艮第红 */
    --secondary-color: #a13c52;        /* 次要勃艮第红 */
    --accent-color: #d4a574;           /* 黄金色 */
    --text-dark: #1a1a1a;
    --text-light: #6b6b6b;
    --bg-light: #f5f5f7;
    --bg-white: #ffffff;
    --glass-light: rgba(255, 255, 255, 0.7);
    --glass-dark: rgba(107, 29, 43, 0.1);
    --shadow: 0 10px 40px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.12);
    --shadow-xl: 0 30px 80px rgba(0, 0, 0, 0.15);
    --transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    --transition-smooth: all 0.35s ease-out;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", system-ui, sans-serif;
    color: var(--text-dark);
    background-color: var(--bg-white);
    line-height: 1.6;
    overflow-x: hidden;
    letter-spacing: -0.3px;
}

/* 导航栏 - Apple 液态玻璃风格 */
.navbar {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid rgba(255, 255, 255, 0.18);
    padding: 0.8rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow);
    animation: slideDown 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 2rem;
}

.nav-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.85rem;
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    letter-spacing: -0.5px;
    text-decoration: none;
    transition: var(--transition-smooth);
}

.nav-brand:hover {
    color: var(--primary-light);
    transform: scale(1.02);
}

.card-logo {
    display: flex;
    align-items: center;
    gap: 0.9rem;
    margin-bottom: 1rem;
    /* prevent the logo container from shrinking when space is tight */
    flex: 0 0 auto;
}

.org-logo {
    /* width/height can be manually controlled via CSS variables or inline style */
    width: var(--org-logo-width, 220px) !important;
    height: var(--org-logo-height, auto) !important;
    max-width: var(--org-logo-max-width, 100%) !important;
    max-height: var(--org-logo-max-height, 240px) !important;
    object-fit: contain;
    display: block;
    border-radius: 0;
    background: transparent;
    border: none;
    padding: 0;
    box-shadow: none;
}

/* Convenience helper classes */
.org-logo--small { --org-logo-width: 120px; }
.org-logo--medium { --org-logo-width: 180px; }
.org-logo--large { --org-logo-width: 240px; }
.org-logo--xlarge { --org-logo-width: 320px; }

/* Center logo inside its wrapper */
.org-logo--center {
    margin-left: auto;
    margin-right: auto;
}

/* Force-fill helper: use when you want the image to fill and crop to the box */
.org-logo--fill {
    object-fit: cover !important;
}

/* Convenience classes to control logo width from the wrapper */
.card-logo--small { --org-logo-width: 120px; }
.card-logo--medium { --org-logo-width: 180px; }
.card-logo--large { --org-logo-width: 240px; }
.card-logo--xlarge { --org-logo-width: 320px; }
.card-logo--center {
    justify-content: center;
}

.logo-fallback {
    display: none;
    min-width: 44px;
    min-height: 44px;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.15);
    color: var(--bg-white);
    font-size: 0.95rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    text-align: center;
    padding: 0.8rem;
    border: 1px solid rgba(255, 255, 255, 0.18);
}

.social-link {
    color: var(--primary-color);
    font-weight: 600;
    text-decoration: none;
    transition: color 0.3s ease;
}

.social-link:hover {
    color: var(--primary-light);
}

.nav-avatar {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid rgba(255, 255, 255, 0.42);
    box-shadow: 0 8px 30px rgba(107, 29, 43, 0.15);
    background: rgba(255, 255, 255, 0.12);
}

.nav-brand-text {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
}

.nav-name {
    font-size: 1rem;
    font-weight: 700;
}

.nav-role {
    font-size: 0.75rem;
    color: rgba(26, 26, 26, 0.72);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2.5rem;
}

.nav-link {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition-smooth);
    position: relative;
    padding: 0.5rem 0;
}

.nav-link:hover {
    color: var(--primary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    transition: width 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--bg-white);
    margin: 5px 0;
    transition: var(--transition);
    border-radius: 2px;
}

/* Hero Section - Apple 风格 */
.hero {
    background: linear-gradient(135deg, #2c0e1a 0%, #6b1d2b 50%, #8b2c42 100%);
    color: var(--bg-white);
    padding: 100px 0;
    min-height: 80vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 50%, rgba(212, 165, 116, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 80%, rgba(139, 44, 66, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
    animation: fadeInUp 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.2s both;
}

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

.hero-image {
    text-align: center;
    animation: floatImage 3s ease-in-out infinite;
}

.avatar-frame {
    display: inline-flex;
    position: relative;
    width: 100%;
    max-width: 360px;
    min-height: 360px;
    align-items: center;
    justify-content: center;
}

.avatar-placeholder {
    width: 320px;
    height: 320px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.14);
    border: 3px solid rgba(255, 255, 255, 0.32);
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(255, 255, 255, 0.96);
    font-size: 3rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    box-shadow: 0 0 60px rgba(212, 165, 116, 0.25),
                inset 0 0 25px rgba(255, 255, 255, 0.1);
}

@keyframes floatImage {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

.profile-pic {
    width: 320px;
    height: 320px;
    border-radius: 50%;
    border: 3px solid rgba(255, 255, 255, 0.3);
    object-fit: cover;
    box-shadow: 0 0 60px rgba(212, 165, 116, 0.3),
                inset 0 0 30px rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    animation: slideInLeft 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.3s both;
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.profile-pic:hover {
    transform: scale(1.05);
    box-shadow: 0 0 80px rgba(212, 165, 116, 0.5),
                inset 0 0 30px rgba(255, 255, 255, 0.2);
}

.hero-title {
    font-size: 3.8rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -1px;
    line-height: 1.1;
    animation: slideInRight 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.4s both;
}

.hero-tagline {
    display: block;
    font-size: 1.3rem;
    margin: 0.8rem 0 1.4rem;
    color: rgba(255, 255, 255, 0.88);
    font-weight: 400;
    letter-spacing: 0.2px;
}

.hero-links {
    margin-bottom: 1.6rem;
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.92);
}

.hero-links a {
    color: rgba(255, 255, 255, 0.95);
    text-decoration: underline;
}

.hero-links a:hover {
    color: var(--accent-color);
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.chinese-name {
    display: block;
    font-size: 2.2rem;
    font-weight: 600;
    color: var(--accent-color);
    margin-top: 0.3rem;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero-subtitle {
    font-size: 1.4rem;
    font-weight: 300;
    margin-bottom: 1.2rem;
    opacity: 0.95;
    letter-spacing: 0.5px;
    animation: fadeInUp 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.5s both;
}

.hero-description {
    font-size: 1.05rem;
    margin-bottom: 2.5rem;
    line-height: 1.8;
    opacity: 0.9;
    animation: fadeInUp 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.6s both;
}

.hero-buttons {
    display: flex;
    gap: 1.5rem;
    animation: fadeInUp 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.7s both;
}

/* 按钮样式 - Apple 风格 */
.btn {
    padding: 14px 32px;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
    text-align: center;
    letter-spacing: 0.3px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: var(--bg-white);
    box-shadow: 0 8px 30px rgba(107, 29, 43, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(107, 29, 43, 0.4);
    background: linear-gradient(135deg, var(--primary-light), var(--secondary-color));
}

.btn-primary:active {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(107, 29, 43, 0.3);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: var(--bg-white);
    border: 1.5px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.5);
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
}

.btn-secondary:active {
    transform: translateY(-1px);
}

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

/* 标题样式 - Apple 现代风格 */
.section-title {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 3rem;
    text-align: center;
    color: var(--text-dark);
    position: relative;
    padding-bottom: 1.5rem;
    letter-spacing: -0.5px;
    animation: slideInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

.section-title::after {
    content: '';
    position: absolute;
    width: 50px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
    animation: scaleX 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.2s both;
}

@keyframes scaleX {
    from {
        transform: translateX(-50%) scaleX(0);
    }
    to {
        transform: translateX(-50%) scaleX(1);
    }
}

/* 关于部分 */
.about {
    padding: 100px 0;
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
    position: relative;
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-content p {
    font-size: 1.05rem;
    color: var(--text-light);
    margin-bottom: 1.5rem;
    line-height: 1.8;
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) 0.2s both;
}

.contact-info {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: var(--transition-smooth);
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) 0.4s both;
}

.contact-info:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
    background: rgba(255, 255, 255, 0.85);
}

.contact-info p {
    margin-bottom: 1rem;
    color: var(--text-dark);
    font-weight: 500;
}

/* 教育背景 */
.education {
    padding: 100px 0;
    background: linear-gradient(180deg, #ffffff 0%, #f5f5f7 100%);
    position: relative;
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
}

.education-card {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.education-card:nth-child(1) {
    animation-delay: 0.1s;
}

.education-card:nth-child(2) {
    animation-delay: 0.2s;
}

.education-card:nth-child(3) {
    animation-delay: 0.3s;
}

.education-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(212, 165, 116, 0.1), transparent);
    transition: left 0.6s ease;
}

.education-card:hover::before {
    left: 100%;
}

.education-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(107, 29, 43, 0.15);
    border-color: rgba(212, 165, 116, 0.3);
}

.education-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
    position: relative;
    z-index: 1;
}

.education-card h3 {
    font-size: 1.25rem;
    color: var(--primary-color);
    font-weight: 600;
}

.degree {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: var(--bg-white);
    padding: 5px 14px;
    border-radius: 8px;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.3px;
    box-shadow: 0 4px 15px rgba(107, 29, 43, 0.2);
}

.major {
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

.dates {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.description {
    color: var(--text-light);
    line-height: 1.6;
}

.education-card .highlights {
    list-style: none;
    margin-top: 1rem;
}

.education-card .highlights li {
    padding: 0.5rem 0;
    color: var(--text-light);
    border-bottom: 1px solid rgba(107, 29, 43, 0.1);
    font-size: 0.95rem;
}

.education-card .highlights li::before {
    content: '✓ ';
    color: var(--accent-color);
    font-weight: bold;
    margin-right: 0.5rem;
}

/* 实习经历 */
.experience {
    padding: 100px 0;
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
    position: relative;
}

.timeline {
    position: relative;
    padding: 2rem 0;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 100%;
    background: linear-gradient(180deg, var(--primary-color), var(--accent-color));
}

.timeline-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
    position: relative;
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.timeline-item:nth-child(1) {
    animation-delay: 0.1s;
}

.timeline-item:nth-child(2) {
    animation-delay: 0.2s;
}

.timeline-item:nth-child(3) {
    animation-delay: 0.3s;
}

.timeline-item:nth-child(4) {
    animation-delay: 0.4s;
}

.timeline-item:nth-child(odd) .timeline-content {
    grid-column: 1 / 2;
}

.timeline-item:nth-child(even) .timeline-content {
    grid-column: 2 / 3;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 18px;
    height: 18px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border: 4px solid var(--bg-light);
    border-radius: 50%;
    top: 20px;
    z-index: 10;
    box-shadow: 0 0 0 6px rgba(107, 29, 43, 0.1);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.timeline-item:hover .timeline-marker {
    transform: translateX(-50%) scale(1.3);
    box-shadow: 0 0 0 8px rgba(107, 29, 43, 0.2);
}

.timeline-content {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
}

.timeline-content:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(107, 29, 43, 0.15);
    border-color: rgba(212, 165, 116, 0.3);
}

.exp-header h3 {
    font-size: 1.3rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.exp-title {
    display: block;
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.exp-date {
    display: block;
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.exp-details {
    list-style: none;
    color: var(--text-light);
}

.exp-details li {
    padding: 0.6rem 0;
    padding-left: 1.5rem;
    position: relative;
    line-height: 1.6;
    font-size: 0.95rem;
}

.exp-details li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--accent-color);
    font-weight: bold;
}

/* 科研经历 */
.research {
    padding: 100px 0;
    background: linear-gradient(180deg, #ffffff 0%, #f5f5f7 100%);
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.5rem;
}

.research-card {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.research-card:nth-child(1) {
    animation-delay: 0.1s;
}

.research-card:nth-child(2) {
    animation-delay: 0.2s;
}

.research-card:nth-child(3) {
    animation-delay: 0.3s;
}

.research-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
}

.research-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(107, 29, 43, 0.15);
    border-color: rgba(212, 165, 116, 0.3);
}

.research-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
    font-weight: 600;
}

.research-card .dates {
    margin-bottom: 1rem;
}

.research-card ul {
    list-style: none;
    color: var(--text-light);
}

.research-card ul li {
    padding: 0.6rem 0;
    padding-left: 1.5rem;
    position: relative;
    line-height: 1.6;
    font-size: 0.95rem;
}

.research-card ul li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--accent-color);
    font-weight: bold;
    font-size: 1.3rem;
}

/* 论文发表 */
.papers {
    padding: 100px 0;
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
}

.papers-list {
    max-width: 900px;
    margin: 0 auto;
}

.paper-item {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.paper-item:nth-child(1) {
    animation-delay: 0.1s;
}

.paper-item:nth-child(2) {
    animation-delay: 0.2s;
}

.paper-item:hover {
    box-shadow: 0 12px 40px rgba(107, 29, 43, 0.15);
    transform: translateX(5px);
    border-color: rgba(212, 165, 116, 0.3);
}

.paper-number {
    flex-shrink: 0;
    width: 45px;
    height: 45px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: var(--bg-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.1rem;
    box-shadow: 0 4px 15px rgba(107, 29, 43, 0.2);
}

.paper-content h4 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
    font-weight: 600;
}

.authors {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.venue {
    color: var(--accent-color);
    font-style: italic;
    font-size: 0.95rem;
}

/* 技能 */
.skills {
    padding: 100px 0;
    background: linear-gradient(180deg, #ffffff 0%, #f5f5f7 100%);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
}

.skill-category {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    text-align: center;
    transition: var(--transition);
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.skill-category:nth-child(1) {
    animation-delay: 0.1s;
}

.skill-category:nth-child(2) {
    animation-delay: 0.2s;
}

.skill-category:nth-child(3) {
    animation-delay: 0.3s;
}

.skill-category:nth-child(4) {
    animation-delay: 0.4s;
}

.skill-category:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(107, 29, 43, 0.15);
    background: linear-gradient(135deg, rgba(107, 29, 43, 0.05), rgba(212, 165, 116, 0.05));
    border-color: rgba(212, 165, 116, 0.3);
}

.skill-category h3 {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
    font-weight: 600;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
    justify-content: center;
}

.skill-tag {
    background: var(--primary-color);
    color: var(--bg-white);
    padding: 0.6rem 1.2rem;
    border-radius: 12px;
    font-size: 0.9rem;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(107, 29, 43, 0.2);
    letter-spacing: 0.2px;
}

.skill-tag:hover {
    transform: translateY(-3px) scale(1.05);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    box-shadow: 0 8px 25px rgba(107, 29, 43, 0.3);
}

/* 联系方式 */
.contact {
    padding: 100px 0;
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
    position: relative;
}

.contact-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2.5rem;
    margin-bottom: 4rem;
}

.contact-info-box {
    background: var(--glass-light);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    text-align: center;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
    animation: fadeInUp 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.contact-info-box:nth-child(1) {
    animation-delay: 0.1s;
}

.contact-info-box:nth-child(2) {
    animation-delay: 0.2s;
}

.contact-info-box:nth-child(3) {
    animation-delay: 0.3s;
}

.contact-info-box:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(107, 29, 43, 0.15);
    border-color: rgba(212, 165, 116, 0.3);
}

.contact-info-box h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.3rem;
    font-weight: 600;
}

.contact-info-box p {
    color: var(--text-light);
    line-height: 1.6;
}

.social-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition-smooth);
    display: inline-block;
}

.social-link:hover {
    color: var(--accent-color);
    transform: translateY(-2px);
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    animation: fadeInUp 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) 0.4s both;
}

.contact-form input,
.contact-form textarea {
    padding: 14px 16px;
    border: 1.5px solid rgba(107, 29, 43, 0.2);
    border-radius: 12px;
    font-family: inherit;
    font-size: 1rem;
    background: var(--glass-light);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: var(--text-dark);
    transition: var(--transition-smooth);
    letter-spacing: 0.2px;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
    color: rgba(107, 29, 43, 0.4);
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(107, 29, 43, 0.1),
                inset 0 0 0 1px rgba(212, 165, 116, 0.2);
    background: rgba(255, 255, 255, 0.8);
}

/* 页脚 */
.footer {
    background: linear-gradient(135deg, #2c0e1a 0%, #6b1d2b 100%);
    color: var(--bg-white);
    padding: 2.5rem 0;
    text-align: center;
    font-weight: 500;
    letter-spacing: 0.3px;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .profile-pic {
        width: 280px;
        height: 280px;
    }

    .hero-title {
        font-size: 2.8rem;
    }

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

    .timeline::before {
        left: 30px;
    }

    .timeline-item {
        grid-template-columns: 70px 1fr;
    }

    .timeline-item:nth-child(odd) .timeline-content,
    .timeline-item:nth-child(even) .timeline-content {
        grid-column: 2 / 3;
    }

    .timeline-marker {
        left: 30px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .nav-menu.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(255, 255, 255, 0.92);
        backdrop-filter: blur(20px);
        border-bottom: 1px solid rgba(255, 255, 255, 0.18);
        padding: 1rem 2rem;
        gap: 1rem;
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.08);
    }

    .nav-menu.active li {
        width: 100%;
    }

    .nav-menu.active .nav-link {
        width: 100%;
        padding: 0.75rem 0;
        color: var(--text-dark);
    }

    .hamburger {
        display: flex;
    }

    .hero-title {
        font-size: 2.2rem;
    }

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

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

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }

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

    .hero-description {
        font-size: 0.95rem;
    }

    .profile-pic {
        width: 220px;
        height: 220px;
    }

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

    .timeline {
        padding-left: 60px;
    }

    .timeline::before {
        left: 30px;
    }

    .timeline-marker {
        left: 21px;
    }

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

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

    .paper-item {
        flex-direction: column;
        gap: 1rem;
    }
}

@media (max-width: 480px) {
    .nav-brand {
        font-size: 1.3rem;
    }

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

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

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

    .profile-pic {
        width: 160px;
        height: 160px;
    }

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

    .container {
        padding: 0 1rem;
    }

    .btn {
        padding: 12px 24px;
        font-size: 0.9rem;
    }

    .education-header {
        flex-direction: column;
    }

    .skill-tags {
        gap: 0.6rem;
    }

    .skill-tag {
        padding: 0.5rem 0.9rem;
        font-size: 0.85rem;
    }
}

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-light);
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--primary-color), var(--accent-color));
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, var(--primary-light), var(--accent-color));
}