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

:root {
    --primary-color: #E2E8F0;
    --secondary-color: #0EA5E9;
    --accent-color: #F472B6;
    --text-color: #E2E8F0;
    --light-gray: #16213E;
    --border-color: #2D3748;
    --background-color: #1A1A2E;
    --card-background: #16213E;
    --shadow: 0 4px 20px rgba(0,0,0,0.3);
    --transition: all 0.3s ease;
}

body {
    font-family: 'Microsoft YaHei', 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏样式 */
header {
    background-color: var(--card-background);
    box-shadow: var(--shadow);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

nav .nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: bold;
    text-decoration: none;
    transition: var(--transition);
}

.logo-img {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    object-fit: cover;
    filter: brightness(1.1) contrast(1.1);
    transition: var(--transition);
    border: 2px solid var(--secondary-color);
}

.logo-text {
    font-size: 24px;
    color: var(--primary-color);
    font-weight: bold;
}

.logo:hover .logo-img {
    filter: brightness(1.2) contrast(1.2) drop-shadow(0 0 8px var(--secondary-color));
    transform: scale(1.05);
}

.logo:hover .logo-text {
    color: var(--secondary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 40px;
}

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
    padding: 10px 0;
    position: relative;
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--secondary-color);
}

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

.bar {
    width: 25px;
    height: 3px;
    background-color: var(--text-color);
    margin: 3px 0;
    transition: var(--transition);
}

/* 主要内容区域 */
main {
    margin-top: 70px;
}

.section {
    display: none;
    padding: 60px 0;
    min-height: calc(100vh - 70px);
}

.section.active {
    display: block;
}

/* 首页样式 */
#home {
    background-color: var(--background-color);
}

.hero-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-top: 40px;
    width: 100%;
}

.intro-text {
    max-width: 1200px;
    margin: 0 auto;
    text-align: left;
}

.intro-text h1 {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.intro-text h2 {
    font-size: 24px;
    color: var(--secondary-color);
    margin-bottom: 10px;
}

.affiliation {
    font-size: 18px;
    color: var(--secondary-color);
    margin-bottom: 30px;
    font-weight: 500;
}

.intro-description {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-color);
    opacity: 0.9;
}

.section-divider {
    height: 2px;
    background: linear-gradient(to right, transparent, var(--secondary-color), transparent);
    margin: 50px 0;
    opacity: 0.5;
}

.content-divider {
    height: 3px;
    background: linear-gradient(90deg,
        transparent 0%,
        var(--accent-color) 20%,
        var(--secondary-color) 50%,
        var(--accent-color) 80%,
        transparent 100%
    );
    margin: 30px 0 50px 0;
    border-radius: 2px;
    position: relative;
    overflow: hidden;
}

.content-divider::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg,
        transparent 0%,
        rgba(14, 165, 233, 0.4) 50%,
        transparent 100%
    );
    animation: shimmer 3s ease-in-out infinite;
}

@keyframes shimmer {
    0% {
        left: -100%;
    }
    50% {
        left: 100%;
    }
    100% {
        left: -100%;
    }
}

.gallery-title {
    font-size: 32px;
    color: var(--primary-color);
    text-align: center;
    margin-bottom: 40px;
    position: relative;
}

.gallery-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background: var(--secondary-color);
    border-radius: 2px;
}

.image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
    padding: 30px 0;
    max-width: 1200px;
    margin: 0 auto;
}

.gallery-item {
    position: relative;
    background: var(--card-background);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    min-height: 450px;
    border: 1px solid var(--border-color);
}

.gallery-item:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 50px rgba(14, 165, 233, 0.2);
    border-color: var(--secondary-color);
}

.gallery-image {
    width: 100%;
    height: 350px;
    object-fit: contain;
    object-position: center;
    transition: transform 0.3s ease;
    flex-shrink: 0;
    background-color: var(--card-background);
    padding: 10px;
    box-sizing: border-box;
}

.gallery-item:hover .gallery-image {
    transform: scale(1.05);
}

.image-caption {
    padding: 25px 20px;
    font-size: 16px;
    font-weight: 500;
    color: var(--text-color);
    text-align: center;
    background: var(--card-background);
    position: relative;
    flex-grow: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1.4;
}

.image-caption::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--accent-color);
    border-radius: 2px;
}

.intro-images {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
}

.image-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
}

/* 研究成果样式 */
#research {
    background-color: var(--background-color);
}

#research h1 {
    text-align: center;
    margin-bottom: 50px;
    font-size: 36px;
    color: var(--primary-color);
}

.content-wrapper {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 40px;
}

.research-content h2 {
    font-size: 24px;
    color: var(--primary-color);
    margin: 30px 0 15px 0;
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 5px;
}

.research-content p {
    margin-bottom: 15px;
    line-height: 1.8;
}

.research-content ul {
    margin-left: 20px;
    margin-bottom: 20px;
}

.research-content li {
    margin-bottom: 8px;
}

.research-sidebar {
    position: sticky;
    top: 90px;
    height: fit-content;
    max-height: calc(100vh - 100px);
    overflow-y: auto;
}

.sidebar-section {
    background: var(--card-background);
    padding: 25px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    margin-bottom: 25px;
    border: 1px solid var(--border-color);
}

.sidebar-section h3 {
    font-size: 18px;
    color: var(--text-color);
    margin-bottom: 15px;
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 5px;
}

.paper-item {
    margin-bottom: 15px;
    padding-bottom: 15px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

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

.paper-item p {
    font-size: 14px;
    line-height: 1.6;
}

.project-item {
    margin-bottom: 20px;
}

.project-item p {
    font-size: 14px;
    line-height: 1.6;
}

.project-item strong {
    color: var(--text-color);
}

/* 研究成果页面的项目卡片样式 */
.research-sidebar .project-item {
    background: var(--card-background);
    padding: 30px;
    border-radius: 15px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 5px solid var(--secondary-color);
    border: 1px solid var(--border-color);
    margin-bottom: 20px;
}

.research-sidebar .project-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(14, 165, 233, 0.15);
    border-left-color: var(--accent-color);
}

/* 教学成果样式 */
#teaching {
    background-color: var(--background-color);
}

#teaching h1 {
    text-align: center;
    margin-bottom: 50px;
    font-size: 36px;
    color: var(--primary-color);
}

.teaching-content h2 {
    font-size: 28px;
    color: var(--primary-color);
    margin: 40px 0 25px 0;
    text-align: left;
}

.achievements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.achievement-card {
    background: var(--card-background);
    padding: 30px;
    border-radius: 15px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 5px solid var(--secondary-color);
    border: 1px solid var(--border-color);
}

.achievement-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(14, 165, 233, 0.15);
    border-left-color: var(--accent-color);
}

.achievement-card h3 {
    font-size: 20px;
    color: var(--text-color);
    margin-bottom: 15px;
    line-height: 1.4;
}

.award {
    font-size: 16px;
    color: var(--secondary-color);
    font-weight: bold;
    margin-bottom: 8px;
}

.students {
    font-size: 14px;
    color: var(--text-color);
    opacity: 0.8;
}

.teaching-projects {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.teaching-projects .project-item {
    background: var(--card-background);
    padding: 30px;
    border-radius: 15px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 5px solid var(--secondary-color);
    border: 1px solid var(--border-color);
}

.teaching-projects .project-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(14, 165, 233, 0.15);
    border-left-color: var(--accent-color);
}

.teaching-projects .project-item h3 {
    font-size: 20px;
    color: var(--text-color);
    margin-bottom: 15px;
    line-height: 1.4;
}

.teaching-projects .project-item p {
    color: var(--text-color);
    line-height: 1.6;
}

/* 产学研合作样式 */
#cooperation {
    background-color: #f8f9fa;
}

#cooperation h1 {
    text-align: center;
    margin-bottom: 50px;
    font-size: 36px;
    color: var(--primary-color);
}

.cooperation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.cooperation-item {
    background: var(--card-background);
    padding: 30px;
    border-radius: 15px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 5px solid var(--secondary-color);
    border: 1px solid var(--border-color);
}

.cooperation-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(14, 165, 233, 0.15);
    border-left-color: var(--accent-color);
}

.cooperation-item h3 {
    font-size: 20px;
    color: var(--text-color);
    margin-bottom: 15px;
    line-height: 1.4;
}

.partner {
    color: var(--secondary-color);
    font-weight: 500;
    font-style: italic;
}

/* 产学研合作样式 */
#cooperation {
    background-color: var(--background-color);
}

#cooperation h1 {
    text-align: center;
    margin-bottom: 50px;
    font-size: 36px;
    color: var(--primary-color);
}

.cooperation-content {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
}

.cooperation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.partner {
    color: var(--secondary-color);
    font-weight: 500;
    margin-top: 10px;
    font-style: italic;
}

/* 页脚样式 */
footer {
    background-color: var(--card-background);
    color: var(--text-color);
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
    opacity: 0.9;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 30px;
}

.footer-left {
    flex: 1;
    min-width: 250px;
}

.footer-left p {
    margin: 0;
    font-size: 14px;
    color: var(--text-color);
    opacity: 0.8;
}

.footer-right {
    flex: 2;
    min-width: 300px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.address, .email {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    color: var(--text-color);
    opacity: 0.9;
}

.address span, .email span {
    line-height: 1.5;
}

.email a {
    color: var(--secondary-color);
    text-decoration: none;
    transition: var(--transition);
}

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

.location-icon, .email-icon {
    font-size: 16px;
    opacity: 0.8;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: var(--shadow);
        padding: 20px 0;
    }

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

    .hamburger {
        display: flex;
    }

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

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }

    .intro-text h1 {
        font-size: 36px;
    }

    .intro-text h2 {
        font-size: 20px;
    }

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

    .research-sidebar {
        position: static;
    }

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

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

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

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

    .gallery-title {
        font-size: 24px;
    }

    .image-gallery {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 25px;
    }

    .gallery-image {
        height: 280px;
    }

    .gallery-item {
        min-height: 380px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    nav .nav-container {
        padding: 0 15px;
    }

    .intro-text h1 {
        font-size: 28px;
    }

    .intro-text h2 {
        font-size: 18px;
    }

    .logo-img {
        width: 35px;
        height: 35px;
    }

    .logo-text {
        font-size: 20px;
    }

    .section {
        padding: 40px 0;
    }

    .achievement-card,
    .project-item,
    .cooperation-item {
        padding: 20px;
    }

    .image-gallery {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .gallery-image {
        height: 250px;
    }

    .gallery-item {
        min-height: 350px;
    }

    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .footer-left, .footer-right {
        min-width: 100%;
        text-align: center;
    }

    .contact-info {
        align-items: center;
    }
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 链接样式 */
a {
    color: var(--secondary-color);
    text-decoration: none;
    transition: var(--transition);
}

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

/* 选中文本样式 */
::selection {
    background-color: var(--secondary-color);
    color: white;
}