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

body {
    font-family: 'Noto Sans SC', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

/* 标题样式 */
h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 15px;
}

h2 {
    font-size: 2.2rem;
    color: #2c3e50;
    text-align: center;
    margin-bottom: 20px;
}

h3 {
    font-size: 1.5rem;
    color: #34495e;
}

/* 隐藏标题（仅用于SEO） */
.hidden-heading {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* 头部样式 */
.header {
    background-color: #2c3e50;
    color: white;
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

.logo h1 {
    font-size: 1.8rem;
    margin-bottom: 5px;
    color: white;
}

.logo-subtitle {
    font-size: 0.9rem;
    color: #ecf0f1;
    opacity: 0.8;
}

.main-nav ul {
    display: flex;
    list-style: none;
}

.main-nav li {
    margin-left: 25px;
}

.main-nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    font-size: 1.1rem;
    transition: color 0.3s;
    padding: 5px 0;
    position: relative;
}

.main-nav a:hover {
    color: #3498db;
}

.main-nav a:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #3498db;
    transition: width 0.3s;
}

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

.search-box {
    display: flex;
    align-items: center;
}

.search-box input {
    padding: 10px 15px;
    border: none;
    border-radius: 4px 0 0 4px;
    font-size: 1rem;
    width: 250px;
}

.search-box button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 10px 15px;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s;
}

.search-box button:hover {
    background-color: #2980b9;
}

/* SEO关键词区域 */
.seo-section {
    background-color: #ecf0f1;
    padding: 20px 0;
    border-bottom: 1px solid #ddd;
}

.keyword-cloud {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
    margin-top: 15px;
}

.keyword-tag {
    background-color: #3498db;
    color: white;
    padding: 8px 15px;
    border-radius: 20px;
    font-size: 0.9rem;
    transition: all 0.3s;
}

.keyword-tag:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

/* 主要区域样式 */
.main-content {
    padding: 40px 0;
}

.section-description {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 40px;
    color: #7f8c8d;
    font-size: 1.1rem;
}

/* 特色内容区域 */
.featured-section {
    margin-bottom: 60px;
}

.featured-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 30px;
}

.featured-item {
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.featured-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
}

.image-container {
    position: relative;
    height: 300px;
    overflow: hidden;
}

.image-container img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s;
}

.featured-item:hover .image-container img {
    transform: scale(1.05);
}

.image-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
    color: white;
    padding: 20px;
    transform: translateY(10px);
    opacity: 0;
    transition: all 0.3s;
}

.featured-item:hover .image-overlay {
    transform: translateY(0);
    opacity: 1;
}

.image-overlay h3 {
    color: white;
    margin-bottom: 10px;
}

/* 分类区域 */
.categories-section {
    background-color: #f8f9fa;
    padding: 60px 0;
    margin-bottom: 60px;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.category-card {
    background-color: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.category-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.category-icon {
    background-color: #3498db;
    color: white;
    width: 70px;
    height: 70px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 1.8rem;
}

.category-card h3 {
    margin-bottom: 15px;
}

.category-card p {
    color: #7f8c8d;
    margin-bottom: 20px;
    font-size: 0.95rem;
}

.category-link {
    display: inline-block;
    color: #3498db;
    text-decoration: none;
    font-weight: 600;
    border-bottom: 2px solid transparent;
    transition: border-color 0.3s;
}

.category-link:hover {
    border-color: #3498db;
}

/* 图片库区域 */
.gallery-section {
    margin-bottom: 60px;
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.gallery-item {
    border-radius: 8px;
    overflow: hidden;
    position: relative;
    height: 250px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s;
}

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

.gallery-item-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 10px;
    transform: translateY(100%);
    transition: transform 0.3s;
}

.gallery-item:hover .gallery-item-caption {
    transform: translateY(0);
}

.load-more {
    text-align: center;
    margin-top: 30px;
}

#loadMoreBtn {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

#loadMoreBtn:hover {
    background-color: #2980b9;
}

/* 视频区域 */
.video-section {
    background-color: #2c3e50;
    color: white;
    padding: 60px 0;
    margin-bottom: 60px;
}

.video-section h2 {
    color: white;
}

.video-section .section-description {
    color: #bdc3c7;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 40px;
}

.video-item {
    background-color: #34495e;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s;
}

.video-item:hover {
    transform: translateY(-10px);
}

.video-placeholder {
    height: 180px;
    background-color: #1a252f;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: #7f8c8d;
}

.video-info {
    padding: 20px;
}

.video-info h3 {
    color: white;
    margin-bottom: 10px;
}

.video-info p {
    color: #bdc3c7;
    font-size: 0.9rem;
}

/* SEO文本区域 */
.seo-text-section {
    background-color: #f8f9fa;
    padding: 60px 0;
    margin-bottom: 60px;
}

.seo-text-section .container {
    max-width: 900px;
}

.seo-text-section h2 {
    text-align: left;
    margin-bottom: 30px;
}

.seo-text-section p {
    margin-bottom: 20px;
    line-height: 1.8;
    color: #555;
}

/* 页脚样式 */
.footer {
    background-color: #2c3e50;
    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 {
    color: white;
    margin-bottom: 20px;
    font-size: 1.4rem;
}

.footer-section p {
    color: #bdc3c7;
    line-height: 1.7;
}

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

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

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section ul li a:hover {
    color: #3498db;
}

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

.footer-keywords span {
    background-color: #34495e;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 0.9rem;
}

.footer-bottom {
    border-top: 1px solid #34495e;
    padding-top: 20px;
    text-align: center;
    color: #bdc3c7;
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 992px) {
    .header .container {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .main-nav {
        margin: 20px 0;
    }
    
    .main-nav ul {
        flex-wrap: wrap;
    }
    
    .main-nav li {
        margin: 0 15px 10px 0;
    }
    
    .search-box {
        width: 100%;
    }
    
    .search-box input {
        width: 100%;
    }
}

@media (max-width: 768px) {
    h2 {
        font-size: 1.8rem;
    }
    
    .featured-grid,
    .categories-grid,
    .gallery-grid,
    .video-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    }
    
    .keyword-tag {
        font-size: 0.8rem;
        padding: 6px 12px;
    }
}