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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #0a0a0a;
}

/* 头部样式 */
.site-header-main {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: #fff;
    padding: 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

.header-top-wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-link-home {
    font-size: 1.8rem;
    font-weight: 700;
    color: #fff;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-menu-horizontal {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu-horizontal a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    padding: 0.5rem 1rem;
}

.nav-menu-horizontal a:hover {
    color: #ff6b6b;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 1.5rem;
    cursor: pointer;
}

/* 英雄区域 */
.hero-section-banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    padding: 4rem 2rem;
    text-align: center;
}

.hero-content-wrapper {
    max-width: 1200px;
    margin: 0 auto;
}

.hero-title-main {
    font-size: 3rem;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero-subtitle-text {
    font-size: 1.3rem;
    opacity: 0.95;
    margin-bottom: 2rem;
}

.cta-button-primary {
    display: inline-block;
    background: #ff6b6b;
    color: #fff;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s;
    box-shadow: 0 4px 15px rgba(255,107,107,0.4);
}

.cta-button-primary:hover {
    background: #ff5252;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255,107,107,0.6);
}

/* 内容区域 */
.content-section-primary {
    max-width: 1200px;
    margin: 3rem auto;
    padding: 0 2rem;
}

.section-title-h2 {
    font-size: 2.2rem;
    margin-bottom: 2rem;
    color: #fff;
    text-align: center;
    position: relative;
    padding-bottom: 1rem;
}

.section-title-h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

/* 视频网格 */
.video-grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.video-card {
    background: #1a1a2e;
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s;
    cursor: pointer;
    opacity: 0;
    transform: translateY(20px);
}

.video-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.video-thumbnail-wrapper {
    position: relative;
    padding-bottom: 56.25%;
    overflow: hidden;
}

.video-thumbnail-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s;
}

.video-card:hover .video-thumbnail-img {
    transform: scale(1.1);
}

.video-info-box {
    padding: 1.2rem;
}

.video-title-h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: #fff;
    font-weight: 600;
}

.video-meta-info {
    display: flex;
    justify-content: space-between;
    color: #999;
    font-size: 0.9rem;
}

/* 特色区域 */
.features-section-highlight {
    background: #16213e;
    padding: 4rem 2rem;
    margin: 3rem 0;
}

.features-grid-layout {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-card-item {
    text-align: center;
    padding: 2rem;
    background: rgba(255,255,255,0.05);
    border-radius: 12px;
    transition: all 0.3s;
}

.feature-card-item:hover {
    background: rgba(255,255,255,0.08);
    transform: translateY(-5px);
}

.feature-icon-wrap {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: #667eea;
}

.feature-title-h3 {
    font-size: 1.3rem;
    margin-bottom: 0.8rem;
    color: #fff;
}

.feature-desc-text {
    color: #bbb;
    line-height: 1.6;
}

/* 页脚 */
.site-footer-main {
    background: #0f0f1e;
    color: #999;
    padding: 3rem 2rem 1.5rem;
    margin-top: 4rem;
}

.footer-content-wrapper {
    max-width: 1200px;
    margin: 0 auto;
}

.footer-grid-sections {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section-block h3 {
    color: #fff;
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.footer-links-list {
    list-style: none;
}

.footer-links-list a {
    color: #999;
    text-decoration: none;
    display: block;
    padding: 0.3rem 0;
    transition: color 0.3s;
}

.footer-links-list a:hover {
    color: #667eea;
}

.footer-bottom-bar {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #333;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu-horizontal {
        display: none;
    }

    .mobile-menu-btn {
        display: block;
    }

    .hero-title-main {
        font-size: 2rem;
    }

    .hero-subtitle-text {
        font-size: 1rem;
    }

    .video-grid-container {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 1.5rem;
    }

    .section-title-h2 {
        font-size: 1.8rem;
    }
}