* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Microsoft YaHei', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: linear-gradient(135deg, #f5f7fa 0%, #e4edf5 100%);
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
header {
    background: linear-gradient(to right, #1a5f9e, #2c8bd1);
    color: white;
    padding: 20px 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo i {
    font-size: 2.5rem;
    color: #ffcc00;
}

.logo h1 {
    font-size: 1.8rem;
    font-weight: bold;
}

.search-container {
    display: flex;
    max-width: 500px;
    width: 100%;
    margin: 15px 0;
}

.search-container input {
    flex: 1;
    padding: 12px 20px;
    border: none;
    border-radius: 30px 0 0 30px;
    font-size: 1rem;
    outline: none;
}

.search-container button {
    background: #ffcc00;
    color: #1a5f9e;
    border: none;
    padding: 12px 25px;
    border-radius: 0 30px 30px 0;
    cursor: pointer;
    font-weight: bold;
    transition: all 0.3s;
}

.search-container button:hover {
    background: #ffd84d;
}

/* 导航样式 */
nav {
    background: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.nav-links {
    display: flex;
    list-style: none;
    padding: 15px 0;
    overflow-x: auto;
}

.nav-links li {
    margin-right: 25px;
    white-space: nowrap;
}

.nav-links a {
    text-decoration: none;
    color: #444;
    font-weight: 500;
    padding: 8px 0;
    position: relative;
    transition: color 0.3s;
}

.nav-links a:hover, .nav-links a.active {
    color: #1a5f9e;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: #1a5f9e;
    border-radius: 3px;
}

/* 主体内容 */
.main-content {
    padding: 40px 0;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 2px solid #e0e6ed;
}

.section-title {
    font-size: 1.5rem;
    color: #1a5f9e;
    font-weight: bold;
}

.section-title i {
    margin-right: 10px;
    color: #ffcc00;
}

.view-more {
    color: #2c8bd1;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
}

.view-more:hover {
    color: #1a5f9e;
    text-decoration: underline;
}

/* 视频网格 */
.video-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
    margin-bottom: 50px;
}

.video-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    cursor: pointer;
}

.video-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 25px rgba(0, 0, 0, 0.15);
}

.video-thumb {
    position: relative;
    height: 180px;
    overflow: hidden;
}

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

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

.video-thumb::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(transparent 60%, rgba(0,0,0,0.7));
    z-index: 1;
}

.play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2;
    opacity: 0.9;
    transition: all 0.3s;
}

.play-btn i {
    color: #1a5f9e;
    font-size: 24px;
    margin-left: 5px;
}

.video-card:hover .play-btn {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1.1);
}

.duration {
    position: absolute;
    bottom: 10px;
    right: 10px;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 3px 8px;
    border-radius: 4px;
    font-size: 0.85rem;
    z-index: 2;
}

.video-info {
    padding: 20px;
}

.video-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: #333;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    height: 3.2em;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    color: #777;
    font-size: 0.9rem;
    margin-top: 5px;
}

/* 分类部分 */
.categories {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 40px;
}

.category-btn {
    background: white;
    border: 1px solid #dde4ee;
    border-radius: 30px;
    padding: 8px 20px;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 0.95rem;
}

.category-btn:hover, .category-btn.active {
    background: #1a5f9e;
    color: white;
    border-color: #1a5f9e;
}

/* 页脚 */


/* 响应式设计 */
@media (max-width: 1100px) {
    .video-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        align-items: flex-start;
    }

    .search-container {
        max-width: 100%;
        margin-top: 20px;
    }

    .video-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .section-title {
        font-size: 1.5rem;
    }
}

@media (max-width: 576px) {
    .video-grid {
        grid-template-columns: 1fr;
    }

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

    .nav-links {
        padding: 10px 0;
    }

    .nav-links li {
        margin-right: 15px;
    }
}

/* 特色样式 */
.highlight {
    background: linear-gradient(120deg, #ffcc00, #ff9900);
    color: #1a2a4f;
    font-weight: bold;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.85rem;
    display: inline-block;
    margin-right: 8px;
}

.hot {
    position: absolute;
    top: 10px;
    left: 10px;
    background: #e74c3c;
    color: white;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: bold;
    z-index: 2;
}