* {
    margin: 0;
    padding: 0;
}

/* Topics Page Styles */
#main-content {
    width: 90%;
    max-width: 1200px;
    margin: 100px auto 40px;
    padding: 20px;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.topics-section {
    text-align: center;
    padding: 40px 20px;
}

.topics-section h2 {
    font-size: 2.8rem;
    margin-bottom: 40px;
    color: #21a1f1;
}

.topic-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    padding: 0 10px;
}

.topic-card {
    background: #fafafa;
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.topic-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.topic-card img {
    width: 100%;
    height: 180px;
    object-fit: cover;
}

.topic-card h3 {
    margin: 15px 0 10px;
    font-size: 1.8rem;
    color: #333;
}

.topic-card p {
    font-size: 1rem;
    padding: 0 15px 15px;
    color: #666;
}

.btn-secondary {
    display: inline-block;
    margin: 0 0 15px;
    padding: 10px 20px;
    background: #61dafb;
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
    transition: background 0.3s ease;
}

.btn-secondary:hover {
    background: #52c0e9;
}