/* ============================================================
   css/pages/learn.css — Learning Hub styles
   ============================================================ */

/* ── Shared hero ── */
.learn-hero {
    padding: 80px 0 60px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.learn-hero::before {
    content: '';
    position: absolute;
    top: -80px; left: 50%; transform: translateX(-50%);
    width: 900px; height: 600px;
    background: radial-gradient(ellipse at center, rgba(0,229,122,0.07) 0%, transparent 65%);
    pointer-events: none;
}
.learn-hero h1 {
    font-family: var(--font-display);
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: var(--space-4);
}
.learn-hero p {
    font-size: var(--text-lg);
    color: var(--text-muted);
    max-width: 560px;
    margin: 0 auto;
    line-height: 1.7;
}
.learn-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-6);
    margin-top: var(--space-6);
    font-size: var(--text-sm);
    color: var(--text-muted);
}
.learn-stat-dot {
    width: 4px; height: 4px;
    border-radius: 50%;
    background: var(--text-faint);
}

/* ── Difficulty filter pills ── */
.learn-filter-bar {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-8);
    flex-wrap: wrap;
}
.learn-filter-label {
    font-size: var(--text-sm);
    color: var(--text-muted);
    margin-right: var(--space-1);
}
.learn-filter-pill {
    display: inline-flex;
    align-items: center;
    padding: 6px 16px;
    border-radius: var(--radius-pill);
    font-size: var(--text-sm);
    font-weight: 500;
    border: 1px solid var(--border);
    color: var(--text-muted);
    background: transparent;
    text-decoration: none;
    transition: all var(--transition-fast);
}
.learn-filter-pill:hover {
    border-color: var(--border-hover);
    color: var(--text);
}
.learn-filter-pill.active {
    background: rgba(0,229,122,0.1);
    border-color: rgba(0,229,122,0.3);
    color: var(--accent-green);
    font-weight: 600;
}

/* ── Track cards grid (learn.php) ── */
.tracks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--space-5);
    margin-bottom: var(--space-16);
}
.track-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    position: relative;
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    display: block;
    transition: border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}
.track-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}
.track-card-accent {
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
}
.track-icon {
    font-size: 2.2rem;
    margin-bottom: var(--space-4);
    display: block;
}
.track-level {
    display: inline-block;
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    padding: 3px 10px;
    border-radius: var(--radius-pill);
    margin-bottom: var(--space-3);
}
.level-beginner     { background: rgba(0,229,122,0.1);  color: var(--accent-green); }
.level-intermediate { background: rgba(255,184,0,0.1);  color: var(--accent-yellow); }
.level-advanced     { background: rgba(255,92,53,0.1);  color: var(--accent-orange); }

.track-title {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: var(--text-md);
    margin-bottom: var(--space-2);
    color: var(--text);
}
.track-desc {
    font-size: var(--text-sm);
    color: var(--text-muted);
    line-height: 1.65;
    margin-bottom: var(--space-5);
}
.track-meta {
    font-size: var(--text-xs);
    color: var(--text-faint);
    display: flex;
    align-items: center;
    gap: 6px;
}

/* ── Breadcrumb ── */
.learn-breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--text-muted);
    margin-bottom: var(--space-8);
}
.learn-breadcrumb a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color var(--transition-fast);
}
.learn-breadcrumb a:hover { color: var(--text); }
.learn-breadcrumb-sep { color: var(--text-faint); }

/* ── Track hero (learn-track.php) ── */
.track-hero {
    padding: 60px 0 48px;
    position: relative;
}
.track-hero-icon {
    font-size: 3rem;
    margin-bottom: var(--space-4);
    display: block;
}
.track-hero h1 {
    font-family: var(--font-display);
    font-size: clamp(1.8rem, 4vw, 3rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.15;
    margin-bottom: var(--space-4);
}
.track-hero-desc {
    font-size: var(--text-md);
    color: var(--text-muted);
    max-width: 640px;
    line-height: 1.7;
    margin-bottom: var(--space-5);
}
.track-hero-meta {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    flex-wrap: wrap;
}
.track-hero-meta-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: var(--text-sm);
    color: var(--text-muted);
}

/* ── Lesson list (learn-track.php) ── */
.lesson-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    margin-bottom: var(--space-16);
}
.lesson-row {
    display: flex;
    align-items: flex-start;
    gap: var(--space-5);
    padding: var(--space-5) var(--space-6);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: inherit;
    transition: border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}
.lesson-row:hover {
    border-color: var(--border-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}
.lesson-number {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 800;
    line-height: 1;
    min-width: 40px;
    padding-top: 2px;
}
.lesson-row-content { flex: 1; min-width: 0; }
.lesson-row-title {
    font-weight: 600;
    font-size: var(--text-md);
    color: var(--text);
    margin-bottom: var(--space-1);
}
.lesson-row-desc {
    font-size: var(--text-sm);
    color: var(--text-muted);
    line-height: 1.6;
}
.lesson-row-meta {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-top: var(--space-2);
}
.lesson-duration {
    font-size: var(--text-xs);
    color: var(--text-faint);
    display: flex;
    align-items: center;
    gap: 4px;
}

/* ── Lesson reader layout (learn-lesson.php) ── */
.learn-lesson-layout {
    display: grid;
    grid-template-columns: 1fr 260px;
    gap: 48px;
    align-items: start;
    margin-bottom: var(--space-16);
}
.lesson-main { min-width: 0; }

/* ── Lesson header ── */
.lesson-header {
    padding: 60px 0 40px;
}
.lesson-header h1 {
    font-family: var(--font-display);
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.15;
    margin-bottom: var(--space-4);
}
.lesson-meta-row {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    flex-wrap: wrap;
    margin-top: var(--space-3);
}
.lesson-meta-item {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: var(--text-sm);
    color: var(--text-muted);
}

/* ── Objectives checklist ── */
.lesson-objectives {
    background: rgba(0,229,122,0.05);
    border: 1px solid rgba(0,229,122,0.15);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    margin-bottom: var(--space-8);
}
.lesson-objectives-title {
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent-green);
    margin-bottom: var(--space-3);
}
.lesson-objectives ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}
.lesson-objectives li {
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--text-muted);
    line-height: 1.5;
}
.lesson-objectives li::before {
    content: '✓';
    color: var(--accent-green);
    font-weight: 700;
    flex-shrink: 0;
    margin-top: 1px;
}

/* ── Lesson prose (body content) ── */
.lesson-prose {
    max-width: 720px;
    line-height: 1.8;
    margin-bottom: var(--space-10);
}
.lesson-prose h2 {
    font-family: var(--font-display);
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--text);
    margin: 2.2em 0 0.7em;
    letter-spacing: -0.01em;
    line-height: 1.25;
}
.lesson-prose h2:first-child { margin-top: 0; }
.lesson-prose p {
    color: var(--text-muted);
    margin-bottom: 1.25em;
    font-size: var(--text-md);
}
.lesson-prose ul,
.lesson-prose ol {
    padding-left: 1.5em;
    margin-bottom: 1.25em;
}
.lesson-prose li {
    color: var(--text-muted);
    margin-bottom: 0.5em;
    line-height: 1.7;
    font-size: var(--text-md);
}
.lesson-prose blockquote {
    border-left: 3px solid var(--accent-cyan);
    margin: 1.8em 0;
    padding: var(--space-3) var(--space-5);
    background: rgba(0,212,255,0.04);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    font-style: italic;
    color: var(--text-muted);
}
.lesson-prose strong { color: var(--text); font-weight: 600; }
.lesson-prose em { color: var(--text); font-style: italic; }

/* ── Takeaways ── */
.lesson-takeaways {
    background: rgba(0,229,122,0.05);
    border: 1px solid rgba(0,229,122,0.15);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    margin-bottom: var(--space-8);
    max-width: 720px;
}
.lesson-takeaways-title {
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent-green);
    margin-bottom: var(--space-3);
}
.lesson-takeaways ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}
.lesson-takeaways li {
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--text-muted);
    line-height: 1.5;
}
.lesson-takeaways li::before {
    content: '→';
    color: var(--accent-green);
    font-weight: 700;
    flex-shrink: 0;
    margin-top: 1px;
}

/* ── Prev / Next nav ── */
.lesson-nav {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-4);
    max-width: 720px;
    margin-top: var(--space-8);
}
.lesson-nav-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-4) var(--space-5);
    text-decoration: none;
    color: inherit;
    transition: border-color var(--transition-fast), transform var(--transition-fast);
    display: block;
}
.lesson-nav-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-2px);
}
.lesson-nav-card.next { text-align: right; }
.lesson-nav-dir {
    font-size: var(--text-xs);
    color: var(--text-faint);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    font-weight: 600;
    margin-bottom: 4px;
}
.lesson-nav-title {
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text);
}

/* ── Track progress sidebar ── */
.track-progress-sidebar {
    position: sticky;
    top: 90px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    max-height: calc(100vh - 120px);
    overflow-y: auto;
}
.track-progress-title {
    font-size: var(--text-xs);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-3);
    border-bottom: 1px solid var(--border);
}
.track-progress-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}
.track-progress-item {
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-sm);
    text-decoration: none;
    font-size: var(--text-sm);
    color: var(--text-muted);
    transition: background var(--transition-fast), color var(--transition-fast);
    line-height: 1.45;
}
.track-progress-item:hover { background: var(--surface-2); color: var(--text); }
.track-progress-item.current {
    background: rgba(255,92,53,0.08);
    color: var(--accent-orange);
    font-weight: 600;
}
.track-progress-num {
    font-size: var(--text-xs);
    font-weight: 700;
    min-width: 18px;
    padding-top: 2px;
    opacity: 0.6;
}
.track-progress-item.current .track-progress-num { opacity: 1; }

/* ── Empty state ── */
.learn-empty {
    text-align: center;
    padding: var(--space-16) var(--space-6);
    color: var(--text-muted);
}
.learn-empty p { margin-bottom: var(--space-5); }

/* ── Responsive ── */
@media (max-width: 960px) {
    .learn-lesson-layout {
        grid-template-columns: 1fr;
    }
    .track-progress-sidebar {
        position: static;
        order: -1;
        max-height: none;
    }
    .lesson-nav {
        grid-template-columns: 1fr;
    }
    .lesson-nav-card.next { text-align: left; }
}
@media (max-width: 640px) {
    .learn-hero { padding: 60px 0 40px; }
    .tracks-grid { grid-template-columns: 1fr; }
    .lesson-header { padding: 40px 0 28px; }
    .lesson-row { flex-direction: column; gap: var(--space-3); }
    .lesson-number { font-size: 1.4rem; }
}