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

:root {
    --primary: #7c3aed;
    --primary-dark: #5b21b6;
    --secondary: #f59e0b;
    --dark: #1f2937;
    --light: #f3f4f6;
    --white: #ffffff;
    --text: #374151;
    --border: #e5e7eb;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: var(--white);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: var(--white);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    cursor: pointer;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    transition: colour 0.3s;
    cursor: pointer;
}

.nav-links a:hover {
    color: var(--primary);
}

/* Page sections - for single-page app */
.page-section {
    display: none;
}

.page-section.active {
    display: block;
}

/* Hero */
.hero {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: var(--white);
    padding: 4rem 0;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero .subtitle {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.hero-meta {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
    margin-top: 2rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
}

/* Sections */
section {
    padding: 4rem 0;
}

section h2 {
    font-size: 2.5rem;
    color: var(--dark);
    margin-bottom: 1rem;
    text-align: center;
}

section .section-intro {
    text-align: center;
    font-size: 1.2rem;
    color: var(--text);
    max-width: 800px;
    margin: 0 auto 3rem;
}

/* Overview Cards */
.overview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.overview-card {
    background: var(--light);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border);
}

.overview-card h3 {
    color: var(--primary);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.overview-card ul {
    list-style: none;
    padding-left: 0;
}

.overview-card li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.overview-card li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--secondary);
    font-weight: bold;
}

/* Frameworks */
.frameworks-grid {
    display: grid;
    gap: 2rem;
    margin-top: 3rem;
}

.framework-card {
    background: var(--white);
    border: 2px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
    transition: transform 0.3s, box-shadow 0.3s;
}

.framework-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0,0,0,0.1);
}

.framework-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.framework-number {
    background: var(--primary);
    color: var(--white);
    width: 48px;
    height: 48px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.5rem;
}

.framework-card h3 {
    color: var(--dark);
    font-size: 1.75rem;
}

.framework-card .description {
    color: var(--text);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.framework-visual {
    background: var(--light);
    padding: 1.5rem;
    border-radius: 8px;
    margin: 1rem 0;
    font-family: monospace;
    font-size: 0.9rem;
    overflow-x: auto;
    white-space: pre;
}

.framework-card .application {
    background: var(--light);
    padding: 1rem;
    border-radius: 8px;
    border-left: 4px solid var(--secondary);
    margin-top: 1rem;
}

.framework-card .application strong {
    color: var(--secondary);
}

/* Exercises */
.exercises-grid {
    display: grid;
    gap: 2rem;
    margin-top: 3rem;
}

.exercise-card {
    background: linear-gradient(to right, var(--white), var(--light));
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
}

.exercise-header {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: 1rem;
}

.exercise-card h3 {
    color: var(--primary);
    font-size: 1.75rem;
    margin-bottom: 0.5rem;
}

.exercise-duration {
    background: var(--secondary);
    color: var(--white);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-weight: 600;
    white-space: nowrap;
}

.exercise-format {
    color: var(--text);
    font-style: italic;
    margin-bottom: 1rem;
}

.exercise-card .learning {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.exercise-card .learning strong {
    color: var(--primary);
}

.highlight-box {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: var(--white);
    padding: 2rem;
    border-radius: 12px;
    margin: 2rem 0;
    text-align: center;
}

.highlight-box h4 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

/* Schedule */
.schedule-timeline {
    max-width: 900px;
    margin: 3rem auto;
}

.timeline-section {
    margin-bottom: 3rem;
}

.timeline-section h3 {
    color: var(--primary);
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--primary);
}

.timeline-item {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    position: relative;
}

.timeline-item:before {
    content: '';
    position: absolute;
    left: 69px;
    top: 48px;
    bottom: -32px;
    width: 2px;
    background: var(--border);
}

.timeline-item:last-child:before {
    display: none;
}

.timeline-time {
    min-width: 120px;
    font-weight: 600;
    color: var(--primary);
    padding-top: 0.5rem;
}

.timeline-content {
    flex: 1;
    background: var(--light);
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid var(--primary);
}

.timeline-content h4 {
    color: var(--dark);
    margin-bottom: 0.5rem;
}

.timeline-content .type {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: var(--primary);
    color: var(--white);
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.timeline-content .type.exercise {
    background: var(--secondary);
}

.timeline-content .type.break {
    background: #9ca3af;
}

.timeline-content .type.core {
    background: #dc2626;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.8; }
}

/* Resources */
.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.resource-card {
    background: var(--white);
    border: 2px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
    text-align: center;
    transition: border-colour 0.3s;
}

.resource-card:hover {
    border-color: var(--primary);
}

.resource-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.resource-card h3 {
    color: var(--dark);
    margin-bottom: 1rem;
}

.resource-card .description {
    color: var(--text);
    margin-bottom: 1.5rem;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: var(--primary);
    color: var(--white);
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    transition: background 0.3s;
}

.btn:hover {
    background: var(--primary-dark);
}

/* Footer */
footer {
    background: var(--dark);
    color: var(--white);
    padding: 3rem 0;
    text-align: center;
}

footer a {
    color: var(--secondary);
    text-decoration: none;
}

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

/* Materials page specific */
.materials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.material-card {
    background: var(--white);
    border: 2px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
    transition: transform 0.3s, box-shadow 0.3s, border-colour 0.3s;
}

.material-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0,0,0,0.1);
    border-color: var(--primary);
}

.material-card h3 {
    color: var(--primary);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.material-card p {
    color: var(--text);
    margin-bottom: 1.5rem;
}

.material-card .actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.material-category {
    margin-bottom: 4rem;
}

.material-category h2 {
    font-size: 2rem;
    color: var(--dark);
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--primary);
    text-align: left;
}

.protected-badge {
    display: inline-block;
    background: #e74c3c;
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-left: 0.5rem;
}

.material-content {
    background: var(--white);
}

.material-header {
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 3px solid var(--primary);
}

.material-header h1 {
    font-size: 2.5rem;
    color: var(--dark);
    margin-bottom: 1rem;
}

.material-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text);
    font-size: 0.95rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.btn-primary {
    display: inline-block;
    background: var(--primary);
    color: var(--white);
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: background 0.3s;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-secondary {
    display: inline-block;
    background: var(--secondary);
    color: var(--white);
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: background 0.3s;
}

.btn-secondary:hover {
    background: #d97706;
}

.material-footer {
    margin-top: 4rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    text-align: center;
}

.material-footer a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 600;
}

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

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

    .hero .subtitle {
        font-size: 1.2rem;
    }

    .hero-meta {
        flex-direction: column;
        gap: 1rem;
    }

    section h2 {
        font-size: 2rem;
    }

    .nav-links {
        display: none;
    }

    .timeline-item {
        flex-direction: column;
        gap: 0.5rem;
    }

    .timeline-item:before {
        display: none;
    }

    .exercise-header {
        flex-direction: column;
        gap: 1rem;
    }

    .materials-grid {
        grid-template-columns: 1fr;
    }

    .material-card .actions {
        flex-direction: column;
    }
}

/* Dropdown Menu */
.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
    align-items: center;
}

.nav-item {
    position: relative;
}

.nav-item.has-dropdown:hover .dropdown-menu,
.dropdown-menu:hover {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: white;
    min-width: 250px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    border-radius: 8px;
    padding: 0.5rem 0;
    margin-top: 0.25rem;
    opacity: 0;
    transform: translateY(-10px);
    transition: all 0.2s ease;
    z-index: 1001;
}

.dropdown-menu::before {
    content: '';
    position: absolute;
    top: -0.5rem;
    left: 0;
    right: 0;
    height: 0.5rem;
    background: transparent;
}

.dropdown-menu a {
    display: block;
    padding: 0.75rem 1.5rem;
    color: var(--text);
    text-decoration: none;
    transition: background 0.2s;
}

.dropdown-menu a:hover {
    background: var(--light);
    color: var(--primary);
}

.dropdown-trigger {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

.dropdown-trigger::after {
    content: '▾';
    font-size: 0.8em;
    transition: transform 0.3s;
}

.nav-item.has-dropdown:hover .dropdown-trigger::after {
    transform: rotate(180deg);
}