:root {
    --primary-color: #2c3e50;
    --secondary-color: #34495e;
    --accent-color: #3498db;
    --accent-light: #5dade2;
    --gradient-accent: linear-gradient(135deg, var(--accent-color), var(--accent-light));
    --success-color: #2ecc71;
    --text-color: #333;
    --light-text: #7f8c8d;
    --background-color: #f5f5f5;
    --card-bg: #ffffff;
    --border-color: #e0e0e0;
    --shadow-light: 0 2px 5px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 5px 15px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 8px 25px rgba(0, 0, 0, 0.15);
    --transition-fast: all 0.2s ease;
    --transition-normal: all 0.3s ease;
    --border-radius-sm: 5px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    /* 新增媒体查询断点变量 */
    --breakpoint-sm: 480px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 1024px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text-color);
    background-color: var(--background-color);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Header Styles */
header {
    text-align: center;
    padding: var(--spacing-xl);
    background-color: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-light);
    position: relative;
    overflow: hidden;
}

header::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0) 100%), url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%239C92AC' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    z-index: 1;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    position: relative;
    z-index: 2;
}

header p {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.9);
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
}

/* Navigation Styles */
nav {
    background-color: var(--secondary-color);
    color: white;
    padding: var(--spacing-md);
    text-align: center;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-light);
}

.nav-section {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: center;
    flex-wrap: nowrap;
    overflow-x: auto;
    padding: 5px 0;
}

.nav-section::-webkit-scrollbar {
    height: 5px;
}

.nav-section::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
}

.nav-section::-webkit-scrollbar-thumb {
    background: var(--accent-color);
    border-radius: 10px;
}

nav a {
    color: white;
    margin: 0 10px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition-normal);
    padding: 8px 12px;
    border-radius: var(--border-radius-sm);
    position: relative;
    white-space: nowrap;
}

nav a:hover {
    color: white;
    background-color: rgba(255, 255, 255, 0.1);
}

nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background-color: var(--accent-color);
    transition: var(--transition-normal);
    transform: translateX(-50%);
}

nav a:hover::after,
nav a.active::after {
    width: 70%;
}

nav a.active {
    background-color: rgba(255, 255, 255, 0.15);
}

/* Section Styles */
section {
    margin: var(--spacing-xl) auto;
    padding: var(--spacing-xl);
    max-width: 1000px;
    background-color: var(--card-bg);
    box-shadow: var(--shadow-medium);
    border-radius: var(--border-radius-lg);
    transition: var(--transition-normal);
}

section:hover {
    box-shadow: var(--shadow-hover);
}

/* Heading Styles */
h2 {
    color: var(--primary-color);
    border-bottom: 3px solid transparent;
    background-clip: text;
    -webkit-background-clip: text;
    padding-bottom: 0.5em;
    margin-top: 0;
    margin-bottom: var(--spacing-lg);
    font-size: 1.8rem;
    position: relative;
    display: inline-block;
    background-image: var(--gradient-accent);
    -webkit-background-clip: text;
    color: transparent;
}

h2::before {
    content: '◆';
    color: var(--accent-color);
    margin-right: 0.5em;
}

h2::after {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--gradient-accent);
    z-index: -1;
    opacity: 0.3;
}

/* List Styles */
ul {
    list-style-type: none;
    padding-left: 0;
    margin: var(--spacing-md) 0;
}

li {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-lg);
    position: relative;
}

li::before {
    content: '•';
    color: var(--accent-color);
    font-size: 1.5rem;
    position: absolute;
    left: 0;
    top: -5px;
}

/* Link Styles */
a {
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition-normal);
}

a:hover {
    color: var(--primary-color);
    text-decoration: underline;
}

/* About Section */
.about-container {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
    padding: var(--spacing-md) 0;
}

.photo {
    width: 200px;
    height: 260px;
    border-radius: var(--border-radius-md);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    transition: var(--transition-normal);
    object-fit: cover;
    border: 5px solid white;
    position: relative;
    z-index: 1;
}

.photo::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: inherit;
    box-shadow: 0 0 0 2px var(--accent-color);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.photo:hover::after {
    opacity: 1;
}

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

.about-text {
    flex: 1;
}

/* Research Interests */
.interests {
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.interest-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-sm);
}

.tag {
    display: inline-block;
    padding: 6px 12px;
    background-color: rgba(52, 152, 219, 0.1);
    color: var(--accent-color);
    border-radius: 30px;
    font-size: 0.9rem;
    transition: var(--transition-normal);
}

.tag:hover {
    background-color: var(--accent-color);
    color: white;
    transform: translateY(-2px);
}

/* Education Section */
.education-item {
    display: flex;
    margin-bottom: var(--spacing-xl);
    align-items: flex-start;
}

.logo {
    width: 100px;
    height: 100px;
    margin-right: var(--spacing-md);
    vertical-align: middle;
    object-fit: contain;
    transition: var(--transition-normal);
    border-radius: var(--border-radius-md);
    padding: 10px;
    background-color: white;
    box-shadow: var(--shadow-light);
    flex-shrink: 0;
}

.logo:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-medium);
}

.education-details {
    flex: 1;
}

.education-details h3 {
    color: var(--primary-color);
    margin-bottom: 5px;
}

.education-details .degree {
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: 5px;
}

.education-details .period {
    color: var(--light-text);
    font-style: italic;
    margin-bottom: var(--spacing-sm);
    display: block;
}

/* Education Map Section */
#education-map {
    padding: 40px 20px;
    background-color: #f8fafc;
}

.map-container {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    margin-bottom: 30px;
}

.map-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
    margin-top: 20px;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 10px;
}

.legend-marker {
    width: 15px;
    height: 15px;
    border-radius: 50%;
}

/* Button Styles */
.resume-button {
    display: inline-block;
    padding: 12px 24px;
    margin-top: var(--spacing-md);
    background: var(--gradient-accent);
    color: white;
    text-decoration: none;
    border-radius: 30px;
    transition: var(--transition-normal);
    font-weight: 600;
    box-shadow: 0 4px 15px rgba(52, 152, 219, 0.3);
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

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

.resume-button:hover::after {
    left: 100%;
}

.resume-button:hover {
    background-color: #27ae60;
    transform: translateY(-2px);
    box-shadow: 0 6px 8px rgba(46, 204, 113, 0.3);
    text-decoration: none;
}

/* Contact Info */
.contact-info {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
    margin-top: var(--spacing-xl);
    padding: var(--spacing-md);
    background-color: rgba(52, 152, 219, 0.05);
    border-radius: var(--border-radius-lg);
}

.contact-info ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.contact-info li {
    margin: var(--spacing-md) 0;
    padding-left: var(--spacing-lg);
    position: relative;
    font-size: 1.1rem;
}

.contact-info li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 20px;
    height: 20px;
    background-size: contain;
    background-repeat: no-repeat;
}

.contact-info li.email::before {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='%233498db'%3E%3Cpath d='M20 4H4c-1.1 0-1.99.9-1.99 2L2 18c0 1.1.9 2 2 2h16c1.1 0 2-.9 2-2V6c0-1.1-.9-2-2-2zm0 4l-8 5-8-5V6l8 5 8-5v2z'/%3E%3C/svg%3E");
}

.contact-info li.github::before {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='%233498db'%3E%3Cpath d='M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10c5.51 0 10-4.48 10-10S17.51 2 12 2zm6.605 4.61a8.502 8.502 0 011.93 5.314c-.281-.054-3.101-.629-5.943-.271-.065-.141-.12-.293-.184-.445a25.416 25.416 0 00-.564-1.236c3.145-1.28 4.577-3.124 4.761-3.362zM12 3.475c2.17 0 4.154.813 5.662 2.148-.152.216-1.443 1.941-4.48 3.08-1.399-2.57-2.95-4.675-3.189-5A8.687 8.687 0 0112 3.475zm-3.633.803a53.896 53.896 0 013.167 4.935c-3.992 1.063-7.517 1.04-7.896 1.04a8.581 8.581 0 014.729-5.975zM3.453 12.01v-.26c.37.01 4.512.065 8.775-1.215.25.477.477.965.694 1.453-.109.033-.228.065-.336.098-4.404 1.42-6.747 5.303-6.942 5.629a8.522 8.522 0 01-2.19-5.705zM12 20.547a8.482 8.482 0 01-5.239-1.8c-.086-.109-.542-.629-.669-1.649.21-.043.43-.086.669-.129 4.37.202 8.594.234 8.942-.678a8.4 8.4 0 01-3.764 3.241zM19.74 14.18a8.468 8.468 0 01-1.761 1.475c-.086.054-1.451.629-4.486.271.022-.119.065-.239.086-.358.25-.975.845-3.016-1.804-6.084a8.4 8.4 0 015.991 4.692z'/%3E%3C/svg%3E");
}

/* Last Modified Date */
.last-modified {
    font-size: 0.9rem;
    color: var(--light-text);
    margin-top: 10px;
    text-align: center;
    font-style: italic;
}

/* Internship Section */
.internship-card {
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    padding: 20px;
    max-width: 800px;
    margin: 0 auto;
}

@media (min-width: 768px) {
    .internship-card {
        flex-direction: row;
        align-items: center;
    }

    .internship-logo {
        margin-bottom: 0;
        margin-right: 30px;
        width: 200px;
        flex-shrink: 0;
    }
}

.internship-logo {
    margin-bottom: 20px;
    text-align: center;
}

.internship-logo .logo {
    width: 150px;
    height: 150px;
    object-fit: contain;
}

.internship-content {
    flex-grow: 1;
}

.internship-date {
    color: #666;
    font-style: italic;
    margin-bottom: 10px;
}

.internship-position {
    font-weight: bold;
    margin-bottom: 10px;
}

.internship-location {
    color: #7f8c8d;
    margin-bottom: 15px;
}

.internship-skills {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
}

.skill-tag {
    background-color: #e0e7ff;
    color: #4338ca;
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 14px;
    transition: background-color 0.3s ease;
}

.skill-tag:hover {
    background-color: #c7d2fe;
}

/* Awards Section */
.awards-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-md);
}

.award-card {
    background-color: var(--card-bg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-medium);
    padding: var(--spacing-md);
    transition: var(--transition-normal);
    display: flex;
    flex-direction: column;
    height: 100%;
    border-top: 4px solid var(--accent-color);
}

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

.award-header {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.award-icon {
    font-size: 2rem;
    color: var(--accent-color);
    margin-right: var(--spacing-sm);
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: rgba(52, 152, 219, 0.1);
    border-radius: 50%;
}

.award-content {
    flex: 1;
}

.award-title {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 5px;
}

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

.award-description {
    margin-bottom: var(--spacing-sm);
}

/* Friends Section */
.friends-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: var(--spacing-lg);
    padding: var(--spacing-md) 0;
}

.friend-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: var(--spacing-md);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-medium);
    transition: var(--transition-normal);
    background-color: white;
    text-decoration: none;
    color: #333;
}

.friend-card:hover {
    transform: translateY(-8px) scale(1.03);
    box-shadow: var(--shadow-hover);
    background: var(--gradient-accent);
}

.friend-card:hover h3,
.friend-card:hover p {
    color: white;
}

.friend-card img {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    margin-bottom: var(--spacing-md);
    object-fit: cover;
    border: 4px solid var(--background-color);
    box-shadow: var(--shadow-light);
    transition: all 0.3s ease;
}

.friend-card:hover img {
    border-color: #e0e7ff;
    box-shadow: 0 0 15px rgba(67, 56, 202, 0.2);
}

.friend-card h3 {
    margin-bottom: var(--spacing-xs);
    color: var(--primary-color);
    transition: color 0.3s ease;
}

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

/* Publications Section */
.publications-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.publication-card {
    background-color: var(--card-bg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-medium);
    overflow: hidden;
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
    display: flex;
    flex-direction: column;
}

@media (min-width: 768px) {
    .publication-card {
        flex-direction: row;
        align-items: center;
    }
}

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

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

.publication-image {
    margin-bottom: var(--spacing-md);
    text-align: center;
}

@media (min-width: 768px) {
    .publication-image {
        margin-bottom: 0;
        margin-right: var(--spacing-md);
        width: 200px;
        flex-shrink: 0;
    }
}

.publication-photo {
    width: 100%;
    max-width: 180px;
    height: auto;
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-light);
    transition: transform var(--transition-normal);
}

.publication-type {
    background-color: var(--accent-color);
    color: white;
    padding: 8px 15px;
    font-size: 0.85rem;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    display: inline-block;
    margin-bottom: var(--spacing-sm);
}

.publication-content {
    padding: var(--spacing-md);
    flex-grow: 1;
}

.authors {
    font-style: italic;
    color: var(--light-text);
    margin-bottom: var(--spacing-xs);
}

.publication-title {
    margin: 0 0 var(--spacing-sm) 0;
    font-size: 1.1rem;
    line-height: 1.4;
}

.publication-title a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-normal);
}

.publication-title a:hover {
    color: var(--accent-color);
    text-decoration: underline;
}

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

/* Timeline Styles */
.timeline {
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md) 0;
}

.timeline::after {
    content: '';
    position: absolute;
    width: 4px;
    background: var(--gradient-accent);
    top: 0;
    bottom: 0;
    left: 50px;
    margin-left: -2px;
    border-radius: 2px;
}

.timeline-item {
    padding: var(--spacing-md) 0;
    position: relative;
    margin-bottom: var(--spacing-lg);
}

.timeline-icon {
    position: absolute;
    width: 100px;
    height: 100px;
    left: 0;
    background-color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-medium);
    z-index: 1;
    transition: var(--transition-normal);
}

.timeline-icon:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-hover);
}

.timeline-icon .logo {
    width: 80px;
    height: 80px;
    object-fit: contain;
    border-radius: 50%;
    padding: 5px;
    max-width: 100%;
    max-height: 100%;
    display: block;
    margin: auto;
}

.timeline-content {
    padding: var(--spacing-md) var(--spacing-md) var(--spacing-md) 130px;
    position: relative;
    background-color: white;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-light);
    transition: var(--transition-normal);
}

.timeline-content:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-5px);
}

.timeline-date {
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: var(--spacing-xs);
    font-size: 0.9rem;
    display: inline-block;
    padding: 3px 8px;
    background-color: rgba(52, 152, 219, 0.1);
    border-radius: var(--border-radius-sm);
}

.timeline-content h3 {
    margin-bottom: var(--spacing-xs);
    color: var(--primary-color);
}

.degree {
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.location {
    color: var(--light-text);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.gpa {
    font-style: italic;
    font-size: 0.9rem;
    color: var(--text-color);
}

/* Footer Styles */
footer {
    text-align: center;
    padding: var(--spacing-lg);
    background-color: var(--secondary-color);
    color: rgba(255, 255, 255, 0.8);
    margin-top: var(--spacing-xl);
    border-top-left-radius: var(--border-radius-lg);
    border-top-right-radius: var(--border-radius-lg);
}

/* Responsive Design */
@media (max-width: var(--breakpoint-lg)) {
    section {
        margin: var(--spacing-lg) var(--spacing-md);
        padding: var(--spacing-lg);
    }
}

@media (max-width: var(--breakpoint-md)) {
    .about-container,
    .education-item,
    .publication-card,
    .internship-card {
        flex-direction: column;
        text-align: center;
    }

    .internship-logo {
        margin-bottom: 0;
        margin-right: 0;
        width: 100%;
    }

    .logo {
        margin-right: 0;
        margin-bottom: var(--spacing-md);
    }

    .timeline::after {
        left: 40px;
    }

    .timeline-icon {
        width: 80px;
        height: 80px;
        left: 0;
    }

    .timeline-icon .logo {
        width: 60px;
        height: 60px;
    }

    .timeline-content {
        padding-left: 110px;
    }

    .publication-image {
        margin-bottom: 0;
        margin-right: 0;
        width: 100%;
    }

    li {
        padding-left: var(--spacing-md);
    }

    nav a {
        display: inline-block;
        margin: 5px;
    }

    header h1 {
        font-size: 2rem;
    }

    .contact-info {
        flex-direction: column;
        align-items: center;
        gap: var(--spacing-md);
    }
}

@media (max-width: var(--breakpoint-sm)) {
    header {
        padding: var(--spacing-lg) var(--spacing-sm);
    }

    header h1 {
        font-size: 1.6rem;
    }

    header p {
        font-size: 1rem;
    }

    section {
        padding: var(--spacing-md);
        margin: var(--spacing-md) var(--spacing-xs);
    }

    h2 {
        font-size: 1.5rem;
    }

    nav {
        padding: var(--spacing-sm);
    }

    nav a {
        margin: 3px;
        padding: 6px 8px;
        font-size: 0.9rem;
    }

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

    .timeline-icon {
        width: 60px;
        height: 60px;
    }

    .timeline-icon .logo {
        width: 40px;
        height: 40px;
    }

    .timeline-content {
        padding-left: 80px;
        padding: var(--spacing-sm);
        margin-left: 20px;
    }

    .map-legend {
        flex-direction: column;
        align-items: center;
    }
}