* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Open Sans', Arial, sans-serif;
    line-height: 1.6;
    color: #002a41; /* Durham Ink */
    background: #f9f9f9;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
}

header {
    background: #68246d; /* Durham Purple */
    color: white;
    padding: 3rem 2rem;
    text-align: left;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

header p {
    font-size: 1.2rem;
    opacity: 0.95;
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.arc-link {
    margin-top: 2rem;
}

.btn-highlight {
    background: #ffd53a; /* Durham Yellow */
    color: #002a41; /* Durham Ink */
    font-weight: 600;
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
    border-radius: 4px;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s ease;
    text-transform: none;
}

.btn-highlight:hover {
    background: #ffdf5c;
    transform: translateY(-2px);
}

main {
    padding: 3rem 2rem;
}

section {
    margin-bottom: 4rem;
}

section h2 {
    color: #68246d; /* Durham Purple */
    font-size: 1.75rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 3px solid #68246d;
    text-align: left;
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.course-card {
    border: 1px solid #b3bdb1; /* Durham Concrete */
    border-radius: 4px;
    padding: 1.75rem;
    transition: all 0.3s ease;
    background: white;
}

.course-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(104, 36, 109, 0.15);
    border-color: #68246d;
}

.course-card h3 {
    color: #002a41; /* Durham Ink */
    margin-bottom: 0.875rem;
    font-size: 1.35rem;
    font-weight: 600;
}

.course-card p {
    color: #002a41;
    margin-bottom: 1.25rem;
    font-size: 0.95rem;
    line-height: 1.65;
}

.topics {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-bottom: 1.25rem;
}

.topic-tag {
    background: #a5c8d0; /* Durham Sky */
    color: #002a41;
    padding: 0.35rem 0.875rem;
    border-radius: 3px;
    font-size: 0.85rem;
    font-weight: 500;
}

.course-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 0.625rem 1.25rem;
    border-radius: 4px;
    text-decoration: none;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    font-weight: 600;
}

.btn-primary {
    background: #68246d; /* Durham Purple */
    color: white;
}

.btn-primary:hover {
    background: #7d2d82;
}

.btn-secondary {
    background: white;
    color: #68246d;
    border: 2px solid #68246d;
}

.btn-secondary:hover {
    background: #68246d;
    color: white;
}

.fork-notice {
    margin-top: 1.25rem;
    font-size: 0.85rem;
    color: #666;
    border-top: 1px solid #b3bdb1;
    padding-top: 0.875rem;
    font-style: italic;
}

.upcoming-table,
.past-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1.5rem;
    background: white;
    border: 1px solid #b3bdb1;
}

.upcoming-table thead,
.past-table thead {
    background: #68246d; /* Durham Purple */
    color: white;
}

.upcoming-table th,
.upcoming-table td,
.past-table th,
.past-table td {
    padding: 1rem 1.25rem;
    text-align: left;
    border-bottom: 1px solid #b3bdb1;
}

.upcoming-table tbody tr:hover,
.past-table tbody tr:hover {
    background: #f5f5f5;
}

.upcoming-table a,
.past-table a {
    color: #68246d;
    text-decoration: none;
    font-weight: 600;
}

.upcoming-table a:hover,
.past-table a:hover {
    text-decoration: underline;
}

details {
    margin-top: 1.5rem;
}

summary {
    cursor: pointer;
    font-weight: 600;
    color: #68246d;
    padding: 1rem;
    background: #f5f5f5;
    border: 1px solid #b3bdb1;
    border-radius: 4px;
    transition: background 0.2s ease;
}

summary:hover {
    background: #a5c8d0; /* Durham Sky */
}

.archive-note {
    margin-top: 1.5rem;
    padding: 1rem;
    background: #dacda2; /* Durham Stone */
    border-radius: 4px;
    font-size: 0.9rem;
    color: #002a41;
    border-left: 4px solid #afa961; /* Durham Gold */
}

.no-data {
    padding: 2rem;
    background: #f5f5f5;
    border-radius: 4px;
    color: #002a41;
    text-align: center;
    border: 1px solid #b3bdb1;
}

.metadata {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 2px solid #b3bdb1;
}

.last-updated {
    text-align: center;
    color: #666;
    font-size: 0.9rem;
}

footer {
    background: #002a41; /* Durham Ink */
    padding: 2.5rem 2rem;
    text-align: center;
    color: white;
}

footer strong {
    font-weight: 600;
}

footer a {
    color: #ffd53a; /* Durham Yellow */
    text-decoration: none;
    font-weight: 600;
}

footer a:hover {
    text-decoration: underline;
}

/* Responsive design */
@media (max-width: 768px) {
    body {
        padding: 0;
    }
    
    header {
        padding: 2rem 1.5rem;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    header p {
        font-size: 1rem;
    }
    
    main {
        padding: 2rem 1.5rem;
    }
    
    .course-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .upcoming-table,
    .past-table {
        font-size: 0.9rem;
    }
    
    .upcoming-table th,
    .upcoming-table td,
    .past-table th,
    .past-table td {
        padding: 0.75rem;
    }
}

/* Accessibility enhancements */
@media (prefers-reduced-motion: reduce) {
    * {
        animation: none !important;
        transition: none !important;
    }
}

/* Print styles */
@media print {
    body {
        background: white;
    }
    
    .btn-highlight,
    .btn {
        border: 1px solid #002a41;
        color: #002a41;
        background: white;
    }
    
    a {
        text-decoration: underline;
    }
}