.video-player-section {
    background: #000;
    padding: 40px;
    margin-bottom: 40px;
    border-radius: 12px;
    animation: fadeIn 0.8s ease-out;
}

.video-container {
    max-width: 1000px;
    margin: 0 auto;
    aspect-ratio: 16/9;
    background: linear-gradient(135deg, #1a1a1a, #2d2d2d);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 18px;
}

.video-details {
    padding: 30px;
    background: white;
    border-radius: 12px;
    margin-bottom: 30px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
}

.video-title {
    font-size: 28px;
    color: #2c3e50;
    margin-bottom: 20px;
    line-height: 1.4;
}

.video-info-bar {
    display: flex;
    gap: 30px;
    padding: 20px 0;
    border-top: 1px solid #ecf0f1;
    border-bottom: 1px solid #ecf0f1;
    margin: 20px 0;
    flex-wrap: wrap;
}

.video-info-bar span {
    color: #7f8c8d;
    font-size: 14px;
}

.video-description {
    line-height: 1.8;
    color: #34495e;
    font-size: 15px;
}

.related-videos {
    margin-top: 40px;
}

.related-videos h3 {
    font-size: 24px;
    margin-bottom: 25px;
    color: #2c3e50;
}

.category-section {
    margin-bottom: 40px;
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.category-item {
    background: white;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    border: 2px solid #ecf0f1;
    transition: all 0.3s;
    animation: scaleIn 0.5s ease-out backwards;
}

@keyframes scaleIn {
    from {
        transform: scale(0.8);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

.category-item:hover {
    border-color: #3498db;
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(52, 152, 219, 0.2);
}

.category-item a {
    color: #2c3e50;
    text-decoration: none;
    font-size: 18px;
    font-weight: 500;
}

.topic-detail {
    background: white;
    padding: 40px;
    border-radius: 12px;
    margin-bottom: 30px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
}

.topic-header h2 {
    font-size: 32px;
    color: #2c3e50;
    margin-bottom: 20px;
    line-height: 1.4;
}

.topic-meta-info {
    display: flex;
    gap: 25px;
    padding: 20px 0;
    border-bottom: 2px solid #ecf0f1;
    margin-bottom: 30px;
    color: #7f8c8d;
    flex-wrap: wrap;
}

.topic-content {
    line-height: 1.9;
    font-size: 16px;
    color: #34495e;
}

.topic-content p {
    margin-bottom: 20px;
}

.comments-section {
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
}

.comments-section h3 {
    font-size: 24px;
    margin-bottom: 30px;
    color: #2c3e50;
}

.comment-item {
    padding: 25px;
    border-bottom: 1px solid #ecf0f1;
    transition: background 0.3s;
}

.comment-item:hover {
    background: #f8f9fa;
}

.comment-author {
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 10px;
}

.comment-time {
    color: #95a5a6;
    font-size: 13px;
    margin-left: 15px;
}

.comment-text {
    color: #34495e;
    line-height: 1.7;
    margin-top: 10px;
}

.info-section {
    background: white;
    padding: 40px;
    border-radius: 12px;
    margin-bottom: 30px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
    line-height: 1.9;
}

.info-section h2 {
    font-size: 32px;
    color: #2c3e50;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 3px solid #3498db;
}

.info-section h3 {
    font-size: 22px;
    color: #34495e;
    margin: 30px 0 15px 0;
}

.info-section p {
    color: #34495e;
    margin-bottom: 15px;
}

.info-section ul {
    list-style: none;
    padding-left: 0;
}

.info-section li {
    padding: 12px 0;
    padding-left: 25px;
    position: relative;
    color: #34495e;
}

.info-section li:before {
    content: '▸';
    position: absolute;
    left: 0;
    color: #3498db;
    font-weight: bold;
}

.contact-form {
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #2c3e50;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 15px;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #3498db;
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

.submit-btn {
    background: linear-gradient(to right, #3498db, #2980b9);
    color: white;
    padding: 12px 40px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.3);
}

@media (max-width: 768px) {
    .video-player-section {
        padding: 20px;
    }

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

    .video-info-bar,
    .topic-meta-info {
        flex-direction: column;
        gap: 10px;
    }
}