/* 分类导航 */
.category-nav {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    padding: 20px 0;
    border-radius: 12px;
    margin-bottom: 30px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 15px;
}

.category-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    background: #345f9c;
    border-radius: 12px;
    text-decoration: none;
    color: #fff;
    transition: all 0.3s ease;
}


.category-item:hover {
    transform: translateY(-3px);
    background: linear-gradient(135deg, #4ecdc4, #44a08d);
    color: #fff;
}

.category-icon {
    font-size: 32px;
    margin-bottom: 10px;
}

.category-name {
    font-size: 14px;
    font-weight: 600;
}

/* 视频标签 */
.video-card-tag {
    position: absolute;
    top: 10px;
    left: 10px;
    background: #e74c3c;
    color: #fff;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .banner-content h1 {
        font-size: 32px;
    }
    
    .banner-content p {
        font-size: 16px;
    }
    
    
    
    .category-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .category-icon {
        font-size: 24px;
    }
    
    .category-name {
        font-size: 12px;
    }
}

@media (max-width: 480px) {
    .banner-content h1 {
        font-size: 24px;
    }
    
    
    .category-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .category-item {
        padding: 15px 10px;
    }
}