/* === Reset & Base === */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --bg: #0a0a0f;
    --bg-card: #12121a;
    --bg-card-hover: #1a1a26;
    --bg-dark-section: #06060a;
    --text: #e4e4eb;
    --text-muted: #8888a0;
    --text-dim: #5a5a72;
    --accent: #6c63ff;
    --accent-glow: rgba(108, 99, 255, 0.15);
    --accent2: #00d4aa;
    --accent2-glow: rgba(0, 212, 170, 0.12);
    --accent3: #ff6b6b;
    --border: #1e1e2e;
    --border-light: #2a2a3e;
    --code-bg: #1a1a28;
    --radius: 12px;
    --radius-sm: 8px;
    --success: #00d4aa;
    --locked: #3a3a50;
}

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent2); }

code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.88em;
    background: var(--code-bg);
    padding: 2px 6px;
    border-radius: 4px;
    color: var(--accent2);
}

h1, h2, h3, h4, h5, h6 { line-height: 1.3; font-weight: 700; }

.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }

/* === Navigation === */
.nav {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 100;
    background: rgba(10, 10, 15, 0.88);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}

.nav-inner {
    max-width: 960px;
    margin: 0 auto;
    padding: 16px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo { font-weight: 800; font-size: 1.2rem; color: var(--text); letter-spacing: -0.5px; }
.logo span { color: var(--accent); }

.nav-links { display: flex; gap: 24px; align-items: center; }
.nav-links a { color: var(--text-muted); font-size: 0.9rem; font-weight: 500; }
.nav-links a:hover { color: var(--text); }
.nav-links .nav-btn {
    background: var(--accent);
    color: #fff;
    padding: 6px 16px;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.85rem;
}
.nav-links .nav-btn:hover { background: #5a52e0; color: #fff; }

/* === Hub Hero === */
.hero {
    padding: 130px 0 60px;
    text-align: center;
}

.tag {
    font-size: 0.82rem;
    color: var(--accent);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 18px;
}

.hero h1 {
    font-size: 3.2rem;
    font-weight: 800;
    letter-spacing: -2px;
    margin-bottom: 18px;
    background: linear-gradient(135deg, var(--text) 0%, var(--accent) 60%, var(--accent2) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 1.15rem;
    color: var(--text-muted);
    max-width: 620px;
    margin: 0 auto 40px;
    line-height: 1.6;
}

/* === Progress Bar === */
.progress-bar-container {
    max-width: 500px;
    margin: 0 auto 60px;
}

.progress-bar {
    height: 8px;
    background: var(--border);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 10px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), var(--accent2));
    border-radius: 4px;
    width: 0%;
    transition: width 0.8s ease;
}

.progress-label {
    font-size: 0.82rem;
    color: var(--text-dim);
    text-align: center;
}

/* === Module Cards (Hub) === */
.modules-grid {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-bottom: 60px;
}

.module-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 32px;
    display: flex;
    align-items: center;
    gap: 24px;
    cursor: pointer;
    transition: all 0.3s;
    position: relative;
    overflow: hidden;
}

.module-card.unlocked:hover,
.module-card.completed:hover {
    border-color: var(--accent);
    background: var(--bg-card-hover);
    transform: translateX(4px);
}

.module-card.locked {
    opacity: 0.45;
    cursor: not-allowed;
}

.module-card.locked::after {
    content: '';
    position: absolute;
    inset: 0;
    background: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 10px,
        rgba(255,255,255,0.01) 10px,
        rgba(255,255,255,0.01) 20px
    );
}

.module-num {
    font-size: 2rem;
    font-weight: 800;
    color: var(--accent);
    min-width: 48px;
    text-align: center;
    line-height: 1;
}

.module-card.completed .module-num { color: var(--success); }
.module-card.locked .module-num { color: var(--locked); }

.module-info { flex: 1; }
.module-info h3 { font-size: 1.15rem; margin-bottom: 4px; }
.module-info p { font-size: 0.88rem; color: var(--text-muted); }

.module-meta {
    display: flex;
    gap: 16px;
    font-size: 0.78rem;
    color: var(--text-dim);
    margin-top: 6px;
}

.module-status {
    font-size: 0.8rem;
    font-weight: 600;
    padding: 5px 14px;
    border-radius: 20px;
    white-space: nowrap;
}

.status-unlocked { background: var(--accent-glow); color: var(--accent); }
.status-completed { background: var(--accent2-glow); color: var(--accent2); }
.status-locked { background: rgba(58,58,80,0.3); color: var(--locked); }

/* === Module Page Hero === */
.module-hero {
    padding: 120px 0 48px;
}

.module-hero .module-label {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--accent);
    margin-bottom: 10px;
}

.module-hero h1 {
    font-size: 2.4rem;
    font-weight: 800;
    letter-spacing: -1.5px;
    margin-bottom: 14px;
}

.module-hero .module-desc {
    font-size: 1.05rem;
    color: var(--text-muted);
    max-width: 650px;
    line-height: 1.6;
}

/* === Sections === */
.section { padding: 60px 0; }
.section-dark { background: var(--bg-dark-section); }
.section h2 { font-size: 1.8rem; margin-bottom: 12px; letter-spacing: -1px; }
.section-subtitle { color: var(--text-muted); font-size: 1rem; margin-bottom: 40px; max-width: 680px; }

/* === Week Cards === */
.week-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 20px;
    overflow: hidden;
}

.week-header {
    padding: 22px 28px;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 16px;
}

.week-num {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent);
    background: var(--accent-glow);
    padding: 4px 12px;
    border-radius: 20px;
    white-space: nowrap;
}

.week-header h4 { font-size: 1.08rem; }

.week-check {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-left: auto;
    font-size: 0.78rem;
    color: var(--text-dim);
    cursor: pointer;
}

.week-check input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--accent2);
    cursor: pointer;
}

.week-check.checked { color: var(--accent2); }

.week-body { padding: 28px; }

.week-goal {
    background: var(--accent-glow);
    border: 1px solid rgba(108, 99, 255, 0.2);
    border-radius: var(--radius-sm);
    padding: 14px 20px;
    margin-bottom: 24px;
    font-size: 0.9rem;
}

.week-section { margin-bottom: 28px; }
.week-section:last-child { margin-bottom: 0; }

.week-section h5 {
    font-size: 0.98rem;
    margin-bottom: 12px;
    color: var(--accent2);
}

.week-section p {
    margin-bottom: 12px;
    font-size: 0.9rem;
    color: var(--text-muted);
}

.week-section ol, .week-section ul { margin-left: 20px; margin-bottom: 16px; }
.week-section li { font-size: 0.9rem; margin-bottom: 6px; color: var(--text-muted); }
.week-section li strong { color: var(--text); }
.week-section li ul { margin-top: 6px; }

.repo-name { font-size: 0.86rem; color: var(--text-dim); margin-bottom: 14px; }

/* === Dataset Box === */
.dataset-box {
    background: var(--accent2-glow);
    border: 1px solid rgba(0, 212, 170, 0.2);
    border-radius: var(--radius-sm);
    padding: 14px 18px;
    margin-bottom: 16px;
    font-size: 0.86rem;
}

.dataset-box strong { color: var(--accent2); }

/* === Prompt Box === */
.prompt-box {
    background: var(--code-bg);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    padding: 20px;
    margin-bottom: 20px;
}

.prompt-box h6 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent);
    margin-bottom: 14px;
}

.prompt { margin-bottom: 10px; }
.prompt:last-child { margin-bottom: 0; }

.prompt code {
    display: block;
    background: rgba(0, 0, 0, 0.3);
    padding: 12px 16px;
    border-radius: 6px;
    font-size: 0.8rem;
    line-height: 1.6;
    color: var(--text-muted);
    white-space: pre-wrap;
    word-break: break-word;
}

/* === Concepts Box === */
.concepts-box {
    background: rgba(108, 99, 255, 0.05);
    border: 1px solid rgba(108, 99, 255, 0.15);
    border-radius: var(--radius-sm);
    padding: 20px;
}

.concepts-box h6 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent);
    margin-bottom: 12px;
}

.concepts-box ul { list-style: none; margin: 0; padding: 0; }
.concepts-box li { margin-bottom: 8px; font-size: 0.86rem; color: var(--text-muted); padding-left: 0; }
.concepts-box li strong { color: var(--text); }

/* === Model/Info Table === */
.info-table {
    width: 100%;
    border-collapse: collapse;
    margin: 16px 0;
    font-size: 0.86rem;
}

.info-table th {
    text-align: left;
    padding: 10px 14px;
    background: rgba(108, 99, 255, 0.1);
    color: var(--accent);
    font-weight: 600;
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.info-table td {
    padding: 10px 14px;
    border-bottom: 1px solid var(--border);
    color: var(--text-muted);
}

/* === Vocab Grid === */
.vocab-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
}

.vocab-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 18px;
    transition: border-color 0.3s;
}

.vocab-card:hover { border-color: var(--accent2); }
.vocab-term { font-weight: 700; font-size: 0.92rem; color: var(--accent2); margin-bottom: 5px; }
.vocab-def { font-size: 0.82rem; color: var(--text); margin-bottom: 7px; }
.vocab-analogy { font-size: 0.78rem; color: var(--text-dim); font-style: italic; padding-top: 7px; border-top: 1px solid var(--border); }

/* === About Grid === */
.about-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
    margin-top: 32px;
}

.about-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 26px;
}

.about-icon { font-size: 1.6rem; margin-bottom: 10px; }
.about-item h4 { font-size: 0.95rem; margin-bottom: 6px; }
.about-item p { font-size: 0.86rem; color: var(--text-muted); }

/* === Resources Grid === */
.resources-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.resource-category {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 26px;
}

.resource-category h4 { font-size: 0.95rem; margin-bottom: 14px; color: var(--accent); }
.resource-category ul { list-style: none; padding: 0; }
.resource-category li { font-size: 0.86rem; color: var(--text-muted); margin-bottom: 9px; line-height: 1.5; }

/* === Completion Button === */
.complete-section {
    text-align: center;
    padding: 60px 0;
    border-top: 1px solid var(--border);
}

.complete-btn {
    display: inline-block;
    background: linear-gradient(135deg, var(--accent), #5a52e0);
    color: #fff;
    border: none;
    padding: 16px 48px;
    font-size: 1.05rem;
    font-weight: 700;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    font-family: inherit;
}

.complete-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(108, 99, 255, 0.3);
}

.complete-btn.btn-completed {
    background: linear-gradient(135deg, var(--accent2), #00a88a);
    cursor: default;
}

.complete-hint {
    font-size: 0.82rem;
    color: var(--text-dim);
    margin-top: 12px;
}

/* === Locked Message === */
.locked-message {
    text-align: center;
    padding: 120px 0;
}

.locked-message h2 { font-size: 2rem; margin-bottom: 12px; }
.locked-message p { color: var(--text-muted); margin-bottom: 24px; }

.btn {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    padding: 10px 28px;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: background 0.2s;
}

.btn:hover { background: #5a52e0; color: #fff; }

/* === Prompt Library Section === */
.prompt-category { margin-bottom: 36px; }
.prompt-category h3 { font-size: 1.15rem; margin-bottom: 14px; color: var(--accent2); }
.prompt-lib-item { margin-bottom: 14px; }
.prompt-lib-title { font-weight: 600; font-size: 0.88rem; margin-bottom: 6px; color: var(--text); }

/* === Command Block === */
.cmd-block {
    background: #0d0d14;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 18px 22px;
    margin-bottom: 12px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.84rem;
    line-height: 1.7;
    color: var(--text-muted);
    overflow-x: auto;
}

.cmd-block .cmd-comment { color: var(--text-dim); }
.cmd-block .cmd-keyword { color: var(--accent); }
.cmd-block .cmd-string { color: var(--accent2); }

/* === Tip Box === */
.tip-box {
    background: rgba(255, 107, 107, 0.06);
    border: 1px solid rgba(255, 107, 107, 0.15);
    border-radius: var(--radius-sm);
    padding: 16px 20px;
    margin-bottom: 20px;
    font-size: 0.88rem;
}

.tip-box strong { color: var(--accent3); }
.tip-box p { color: var(--text-muted); margin-bottom: 0; }

/* === Footer === */
.footer {
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--border);
}

.footer p { color: var(--text-muted); font-size: 0.86rem; }
.footer-sub { font-size: 0.78rem; color: var(--text-dim); margin-top: 6px; }

/* === Reset Button === */
.reset-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--text-dim);
    padding: 6px 16px;
    border-radius: 6px;
    font-size: 0.78rem;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
    margin-top: 20px;
}

.reset-btn:hover {
    border-color: var(--accent3);
    color: var(--accent3);
}

/* === Feedback System === */
.feedback-section {
    margin-top: 28px;
    border-top: 1px solid var(--border);
    padding-top: 4px;
}

.feedback-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px 0;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent);
    transition: color 0.2s;
    user-select: none;
}

.feedback-toggle:hover { color: var(--accent2); }

.feedback-toggle-icon {
    font-size: 0.7rem;
    transition: transform 0.3s;
    display: inline-block;
}

.feedback-section.open .feedback-toggle-icon {
    transform: rotate(90deg);
}

.feedback-content {
    display: none;
    padding-bottom: 8px;
}

.feedback-section.open .feedback-content {
    display: block;
}

.rubric {
    margin-bottom: 24px;
}

.rubric h6 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent2);
    margin-bottom: 14px;
}

.rubric-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.rubric-item {
    background: rgba(0, 212, 170, 0.04);
    border: 1px solid rgba(0, 212, 170, 0.12);
    border-radius: var(--radius-sm);
    padding: 16px;
}

.rubric-name {
    font-weight: 600;
    font-size: 0.88rem;
    color: var(--text);
    margin-bottom: 8px;
}

.rubric-weight {
    color: var(--accent2);
    font-size: 0.78rem;
    margin-left: 6px;
}

.rubric-item ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.rubric-item li {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 4px;
    padding-left: 14px;
    position: relative;
}

.rubric-item li::before {
    content: '~';
    position: absolute;
    left: 0;
    color: var(--text-dim);
}

.feedback-steps {
    display: flex;
    gap: 16px;
    margin-bottom: 20px;
}

.feedback-step {
    flex: 1;
    display: flex;
    gap: 10px;
    align-items: flex-start;
}

.step-num {
    background: var(--accent-glow);
    color: var(--accent);
    width: 26px;
    height: 26px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 700;
    flex-shrink: 0;
}

.feedback-step p {
    font-size: 0.84rem;
    color: var(--text-muted);
    margin: 0;
}

.feedback-prompt-box {
    background: #0d0d14;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
    margin-bottom: 16px;
}

.feedback-prompt-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 18px;
    background: rgba(108, 99, 255, 0.06);
    border-bottom: 1px solid var(--border);
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-muted);
}

.feedback-prompt-text {
    padding: 16px 18px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.78rem;
    line-height: 1.65;
    color: var(--text-dim);
    white-space: pre-wrap;
    word-break: break-word;
    margin: 0;
    max-height: 300px;
    overflow-y: auto;
}

.feedback-tip {
    background: rgba(108, 99, 255, 0.05);
    border: 1px solid rgba(108, 99, 255, 0.12);
    border-radius: var(--radius-sm);
    padding: 14px 18px;
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.feedback-tip strong { color: var(--accent); }

.feedback-tip code {
    background: rgba(0,0,0,0.3);
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.8rem;
}

.self-check {
    background: var(--bg-dark-section);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 18px;
}

.self-check h6 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--accent);
    margin-bottom: 12px;
}

.check-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-bottom: 8px;
    cursor: pointer;
}

.check-item input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--accent2);
    cursor: pointer;
}

.copy-btn {
    background: var(--accent-glow);
    border: 1px solid rgba(108, 99, 255, 0.3);
    color: var(--accent);
    padding: 5px 14px;
    border-radius: 5px;
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

.copy-btn:hover { background: rgba(108, 99, 255, 0.25); }
.copy-btn.copied { background: var(--accent2-glow); border-color: rgba(0,212,170,0.3); color: var(--accent2); }

/* === Responsive === */
@media (max-width: 768px) {
    .hero h1 { font-size: 2.2rem; }
    .module-hero h1 { font-size: 1.8rem; }
    .about-grid, .vocab-grid, .resources-grid { grid-template-columns: 1fr; }
    .module-card { flex-direction: column; align-items: flex-start; gap: 12px; }
    .module-status { align-self: flex-start; }
    .nav-links { gap: 14px; }
    .week-header { flex-direction: column; align-items: flex-start; gap: 8px; }
    .week-check { margin-left: 0; }
}

@media (max-width: 480px) {
    .hero h1 { font-size: 1.8rem; }
    .container { padding: 0 16px; }
    .nav-links a:not(.nav-btn) { display: none; }
}