/* CSS重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6ec1e4;
    --secondary-color: #7ed6df;
    --accent-color: #22a6b3;
    --light-color: #f7f9f9;
    --dark-color: #2c3e50;
    --text-color: #333;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s ease;
}

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

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
.header {
    background-color: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 15px 0;
    backdrop-filter: blur(10px);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--dark-color);
    font-size: 24px;
    font-weight: 700;
}

.logo i {
    color: var(--primary-color);
    margin-right: 10px;
    font-size: 28px;
}

.search-box {
    flex: 1;
    max-width: 500px;
    margin: 0 30px;
}

.search-box form {
    display: flex;
    position: relative;
}

.search-box input {
    flex: 1;
    padding: 12px 20px;
    border: 2px solid var(--primary-color);
    border-radius: 30px;
    font-size: 16px;
    outline: none;
    transition: var(--transition);
}

.search-box input:focus {
    box-shadow: 0 0 0 3px rgba(110, 193, 228, 0.2);
}

.search-box button {
    position: absolute;
    right: 5px;
    top: 5px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    cursor: pointer;
    transition: var(--transition);
}

.search-box button:hover {
    background-color: var(--accent-color);
}

.nav {
    display: flex;
}

.nav-link {
    margin-left: 25px;
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 600;
    transition: var(--transition);
    position: relative;
}

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

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

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

.mobile-menu-btn {
    display: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--dark-color);
}

/* 主要内容区域 */
.main-content {
    margin-top: 80px;
}

/* 英雄区域 */
.hero {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('https://tupian.com/1.jpg');
    background-size: cover;
    background-position: center;
    opacity: 0.1;
    z-index: 0;
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
    z-index: 1;
}

.hero-content {
    flex: 1;
    padding-right: 40px;
}

.hero-title {
    font-size: 42px;
    margin-bottom: 20px;
    line-height: 1.2;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.hero-description {
    font-size: 18px;
    margin-bottom: 30px;
    opacity: 0.9;
}

.btn-hero {
    display: inline-block;
    background-color: white;
    color: var(--primary-color);
    padding: 12px 30px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.btn-hero:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.1);
}

.hero-image {
    flex: 1;
    text-align: right;
}

.hero-image img {
    max-width: 100%;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-15px);
    }
}

/* 关键词区域 */
.keyword-section {
    padding: 60px 0;
    background-color: var(--light-color);
}

.keyword-section h2 {
    font-size: 32px;
    margin-bottom: 20px;
    color: var(--dark-color);
    text-align: center;
}

.keyword-section p {
    font-size: 18px;
    margin-bottom: 20px;
    line-height: 1.7;
}

/* 通用部分样式 */
.section {
    padding: 80px 0;
}

.bg-light {
    background-color: var(--light-color);
}

.section-title {
    font-size: 36px;
    text-align: center;
    margin-bottom: 20px;
    color: var(--dark-color);
    position: relative;
}

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

.section-description {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 50px;
    font-size: 18px;
    color: #666;
}

.text-center {
    text-align: center;
    margin-top: 40px;
}

.btn {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 14px 35px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: 2px solid var(--primary-color);
}

.btn:hover {
    background-color: transparent;
    color: var(--primary-color);
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.btn-small {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 8px 20px;
    border-radius: 20px;
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    transition: var(--transition);
}

.btn-small:hover {
    background-color: var(--accent-color);
}

/* 图片网格 */
.picture-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 25px;
}

.picture-card {
    background-color: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
}

.picture-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.picture-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: var(--transition);
}

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

.picture-info {
    padding: 20px;
}

.picture-info h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.picture-info p {
    color: #666;
    font-size: 14px;
}

/* 视频网格 */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
}

.video-card {
    background-color: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.video-thumbnail {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.video-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.video-card:hover .video-thumbnail img {
    transform: scale(1.05);
}

.play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--primary-color);
    transition: var(--transition);
}

.video-card:hover .play-btn {
    background-color: var(--primary-color);
    color: white;
}

.video-info {
    padding: 20px;
}

.video-info h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.video-info p {
    color: #666;
    margin-bottom: 15px;
}

/* 关键词云 */
.keyword-cloud {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
    margin-top: 40px;
}

.keyword-tag {
    padding: 10px 20px;
    background-color: white;
    color: var(--dark-color);
    text-decoration: none;
    border-radius: 30px;
    font-weight: 600;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.keyword-tag:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-3px);
}

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

.keyword-highlight:hover {
    background-color: var(--accent-color);
}

/* 关于区域 */
.about-content {
    display: flex;
    align-items: center;
    gap: 50px;
}

.about-text {
    flex: 1;
}

.about-text p {
    margin-bottom: 20px;
    font-size: 18px;
}

.about-image {
    flex: 1;
}

.about-image img {
    width: 100%;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

/* 页脚 */
.footer {
    background-color: var(--dark-color);
    color: white;
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3 {
    font-size: 22px;
    margin-bottom: 20px;
    color: white;
}

.footer-section p {
    opacity: 0.8;
    line-height: 1.8;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #ddd;
    text-decoration: none;
    transition: var(--transition);
}

.footer-section ul li a:hover {
    color: var(--primary-color);
    padding-left: 5px;
}

.footer-keywords {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.footer-keywords a {
    background-color: rgba(255, 255, 255, 0.1);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 14px;
    text-decoration: none;
    transition: var(--transition);
}

.footer-keywords a:hover {
    background-color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
    font-size: 14px;
    opacity: 0.7;
}

.footer-bottom p {
    margin-bottom: 10px;
}

/* 响应式设计 */
@media (max-width: 992px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-content {
        padding-right: 0;
        margin-bottom: 40px;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .about-content {
        flex-direction: column;
    }
    
    .video-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
}

@media (max-width: 768px) {
    .header .container {
        flex-wrap: wrap;
    }
    
    .search-box {
        order: 3;
        flex: 100%;
        max-width: 100%;
        margin: 15px 0 0;
    }
    
    .nav {
        display: none;
        flex-direction: column;
        width: 100%;
        margin-top: 20px;
    }
    
    .nav.active {
        display: flex;
    }
    
    .nav-link {
        margin: 10px 0;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero-title {
        font-size: 30px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .picture-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
    
    .video-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 26px;
    }
    
    .section {
        padding: 50px 0;
    }
    
    .picture-grid {
        grid-template-columns: 1fr;
    }
    
    .keyword-tag {
        padding: 8px 15px;
        font-size: 14px;
    }
}