:root {
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --accent-color: #e74c3c;
    --light-bg: #f8f9fa;
    --dark-text: #2c3e50;
}

.hero-section {
    background: linear-gradient(135deg, var(--primary-color), #2980b9);
    color: white;
    padding: 1rem 0;
    margin-bottom: 2rem;
    border-radius: 0 0 20px 20px;
}

.section-title {
    color: var(--secondary-color);
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 10px;
    margin-bottom: 20px;
}

.card {
    border: none;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
    margin-bottom: 20px;
    height: 100%;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.15);
}

.card-header {
    background: linear-gradient(135deg, var(--primary-color), #2980b9);
    color: white;
    border-radius: 10px 10px 0 0 !important;
    padding: 15px 20px;
    font-weight: 600;
}

.reference-list {
    list-style: none;
    padding-left: 0;
    max-height: 300px;
    overflow-y: auto;
}

.reference-list li {
    margin-bottom: 8px;
    padding: 8px 0;
    border-bottom: 1px solid #eee;
}

.reference-list li:last-child {
    border-bottom: none;
}

.reference-list a {
    color: var(--secondary-color);
    text-decoration: none;
    transition: color 0.3s;
    display: flex;
    align-items: center;
}

.reference-list a:hover {
    color: var(--primary-color);
}

.reference-list a i {
    margin-right: 8px;
    color: var(--primary-color);
}

.search-container {
    max-width: 500px;
    margin: 0 auto 30px;
}

.footer {
    background-color: var(--secondary-color);
    color: white;
    padding: 30px 0;
    margin-top: 50px;
}

.quick-links a {
    color: #ddd;
    text-decoration: none;
    margin-right: 15px;
}

.quick-links a:hover {
    color: white;
}

.tab-content {
    padding-top: 20px;
}

.nav-tabs .nav-link.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.nav-tabs .nav-link {
    color: var(--secondary-color);
}

@media (max-width: 768px) {
    .hero-section {
        padding: 2rem 0;
    }

    .card {
        margin-bottom: 15px;
    }
}