/* ============================================================
   main.css — Global resets, CSS custom properties, typography
   Blockchain Interactive Learning Platform
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Syne:wght@500;700;800&family=Manrope:wght@400;500;700&family=IBM+Plex+Mono:wght@400;600&family=Oxanium:wght@400;500;600;700&family=Hanken+Grotesk:wght@400;500;600;700;800&display=swap');

/* ---- Custom Properties ---- */
:root {
  /* Colour palette */
  --bg-primary:      #071015;
  --bg-secondary:    #0d1c22;
  --bg-card:         #132730;
  --bg-elevated:     #173441;
  --border-color:    #2f525e;

  --accent-green:    #c8ff22;
  --accent-blue:     #5ae3ff;
  --accent-purple:   #4fc1d6;
  --accent-yellow:   #ffd166;
  --accent-red:      #ff6b6b;
  --accent-coral:    #ff8a5b;

  --text-primary:    #ecf8f7;
  --text-secondary:  #acd0d7;
  --text-muted:      #7ea4aa;
  --text-inverse:    #061117;

  /* Typography */
  --font-sans:   'Manrope', 'Segoe UI', sans-serif;
  --font-display:'Syne', 'Segoe UI', sans-serif;
  --font-mono:   'IBM Plex Mono', 'Fira Code', monospace;
  --font-dashboard-body: 'Hanken Grotesk', 'Segoe UI', sans-serif;
  --font-dashboard-display: 'Oxanium', 'Segoe UI', sans-serif;

  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;

  --font-normal:   400;
  --font-medium:   500;
  --font-semibold: 600;
  --font-bold:     700;

  /* Spacing scale */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Borders & radius */
  --radius-sm:  4px;
  --radius-md:  8px;
  --radius-lg:  12px;
  --radius-xl:  16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 4px 12px rgba(2, 8, 12, 0.35);
  --shadow-md: 0 10px 24px rgba(2, 8, 12, 0.5);
  --shadow-lg: 0 20px 44px rgba(0, 0, 0, 0.6);
  --glow-green: 0 0 22px rgba(200,255,34,0.28);
  --glow-blue:  0 0 22px rgba(90,227,255,0.25);

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow:   400ms ease;
  --ease-out-quart: cubic-bezier(0.25, 1, 0.5, 1);
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);

  /* Canvas surfaces (body gradient stops, modal background) */
  --bg-canvas-deep:  #061015;
  --bg-canvas-mid:   #08171d;
  --bg-modal:        #122730;
  --bg-modal-top:    #173743;

  /* Accent tints */
  --accent-green-light: #d9ff55;

  /* Layout */
  --sidebar-width: 260px;
  --header-height: 64px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  /* RTL toggled dynamically via JS: dir="rtl" on <html> */
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--text-primary);
  background:
    radial-gradient(1200px 700px at 85% -10%, rgba(90,227,255,0.12), transparent 60%),
    radial-gradient(900px 500px at -5% 10%, rgba(200,255,34,0.09), transparent 55%),
    linear-gradient(180deg, var(--bg-canvas-deep) 0%, var(--bg-canvas-mid) 45%, var(--bg-primary) 100%);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(236,248,247,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(236,248,247,0.03) 1px, transparent 1px);
  background-size: 28px 28px;
  mask-image: radial-gradient(closest-side, #000 35%, transparent 100%);
  opacity: 0.35;
  z-index: -2;
}

body::after {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(
    35deg,
    rgba(255,255,255,0.018) 0,
    rgba(255,255,255,0.018) 1px,
    transparent 1px,
    transparent 14px
  );
  opacity: 0.25;
  z-index: -1;
}

/* ---- Typography ---- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

p { margin-block-end: var(--space-4); }

a {
  color: var(--accent-green);
  text-decoration: none;
  transition: color var(--transition-fast), text-shadow var(--transition-fast);
}
a:hover {
  color: var(--accent-blue);
  text-shadow: var(--glow-blue);
}

code, kbd, samp, pre {
  font-family: var(--font-mono);
  font-size: 0.9em;
}

code {
  background: var(--bg-elevated);
  color: var(--accent-green);
  padding: 0.1em 0.4em;
  border-radius: var(--radius-sm);
}

pre {
  background: var(--bg-elevated);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  overflow-x: auto;
  margin-block-end: var(--space-4);
}

pre code {
  background: none;
  padding: 0;
}

ul, ol {
  padding-inline-start: var(--space-6);
  margin-block-end: var(--space-4);
}

li { margin-block-end: var(--space-1); }

/* ---- Layout Shell ---- */
#app {
  display: flex;
  min-height: 100vh;
}

#sidebar {
  width: var(--sidebar-width);
  min-height: 100vh;
  flex-shrink: 0;
  background:
    linear-gradient(180deg, rgba(23,52,65,0.75), rgba(13,28,34,0.92)),
    var(--bg-secondary);
  border-inline-end: 1px solid rgba(90,227,255,0.2);
  @supports (backdrop-filter: blur(1px)) {
    backdrop-filter: blur(8px);
  }
  position: fixed;
  inset-block-start: 0;
  inset-inline-start: 0;
  z-index: 100;
  overflow-y: auto;
  overflow-x: hidden;
  transition: transform var(--transition-normal);
}

#main {
  margin-inline-start: var(--sidebar-width);
  flex: 1;
  min-height: 100vh;
  padding: var(--space-10) clamp(1.25rem, 2.6vw, 3rem);
  max-width: 1080px;
  animation: stage-reveal 600ms cubic-bezier(.16,.84,.22,.99) both;
}

@keyframes stage-reveal {
  from {
    opacity: 0;
    transform: translateY(14px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---- Cards ---- */
.card {
  background:
    linear-gradient(135deg, rgba(23,52,65,0.95), rgba(19,39,48,0.96)),
    var(--bg-card);
  border: 1px solid rgba(90,227,255,0.24);
  border-radius: 18px;
  padding: var(--space-6);
  margin-block-end: var(--space-6);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(120deg, transparent 0 60%, rgba(200,255,34,0.08) 100%);
}

.card::after {
  content: '';
  position: absolute;
  right: -36px;
  top: -36px;
  width: 110px;
  height: 110px;
  border: 1px solid rgba(200,255,34,0.38);
  border-radius: 18px;
  transform: rotate(23deg);
  pointer-events: none;
}

.card:hover {
  border-color: rgba(200,255,34,0.62);
  box-shadow: var(--glow-green), var(--shadow-lg);
  transform: translateY(-2px);
  transition: border-color var(--transition-normal), box-shadow var(--transition-normal), transform var(--transition-normal);
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-5);
  border: none;
  border-radius: 12px;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.01em;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(120deg, color-mix(in oklab, var(--accent-green) 75%, white), var(--accent-green));
  color: var(--text-inverse);
  box-shadow: 0 8px 18px rgba(200,255,34,0.25);
}
.btn-primary:hover {
  background: linear-gradient(120deg, color-mix(in oklab, var(--accent-green) 60%, white), color-mix(in oklab, var(--accent-green) 85%, white));
  box-shadow: var(--glow-green);
  color: var(--text-inverse);
}

.btn-secondary {
  background: linear-gradient(120deg, rgba(90,227,255,0.16), rgba(90,227,255,0.06));
  color: var(--text-primary);
  border: 1px solid rgba(90,227,255,0.36);
}
.btn-secondary:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  box-shadow: var(--glow-blue);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  padding: var(--space-1) var(--space-3);
}
.btn-ghost:hover { color: var(--accent-green); }

.btn:focus-visible,
.dashboard-module:focus-visible,
.dashboard-hero__secondary:focus-visible,
.sidebar__nav-item:focus-visible,
.sidebar__lang-btn:focus-visible,
.sidebar-toggle:focus-visible {
  outline: 2px solid rgba(200, 255, 34, 0.92);
  outline-offset: 3px;
}

/* ---- Badges / Chips ---- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: var(--font-medium);
}

.chip-green  { background: rgba(0,255,136,0.15); color: var(--accent-green); }
.chip-blue   { background: rgba(0,180,216,0.15); color: var(--accent-blue); }
.chip-purple { background: rgba(124,58,237,0.15); color: var(--accent-purple); }
.chip-yellow { background: rgba(251,191,36,0.15); color: var(--accent-yellow); }

/* ---- Progress Bar ---- */
.progress-bar {
  width: 100%;
  height: 6px;
  background: var(--bg-elevated);
  border-radius: var(--radius-full);
  overflow: hidden;
}
.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-green), var(--accent-blue));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

/* ---- Toast / Notification ---- */
.toast-container {
  position: fixed;
  inset-block-end: var(--space-6);
  inset-inline-end: var(--space-6);
  z-index: 500;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  align-items: flex-end;
}

.toast {
  background: var(--bg-elevated);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-3) var(--space-5);
  font-size: var(--text-sm);
  box-shadow: var(--shadow-lg);
  animation: toast-in 0.3s ease forwards;
  max-width: 320px;
}

.toast--xp    { border-color: var(--accent-green); color: var(--accent-green); }
.toast--error { border-color: var(--accent-red);   color: var(--accent-red);   }
.toast--info  { border-color: var(--accent-blue);  color: var(--accent-blue);  }

@keyframes toast-in {
  from { opacity: 0; transform: translateY(var(--space-4)); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ---- Modal overlay ---- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.75);
  z-index: 400;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
}

.modal {
  background: linear-gradient(170deg, var(--bg-modal-top), var(--bg-modal));
  border: 1px solid rgba(90,227,255,0.34);
  border-radius: 18px;
  padding: var(--space-8);
  max-width: 480px;
  width: 100%;
  box-shadow: var(--shadow-lg);
  text-align: center;
}

#main .card,
#main .lesson-content,
#main .quiz-form {
  animation: stagger-in 520ms cubic-bezier(.19,.84,.2,1) both;
}

#main .card:nth-of-type(2) { animation-delay: 70ms; }
#main .card:nth-of-type(3) { animation-delay: 120ms; }
#main .card:nth-of-type(4) { animation-delay: 170ms; }

@keyframes stagger-in {
  from {
    opacity: 0;
    transform: translateY(10px) scale(0.99);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* ---- Utility ---- */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

.text-accent { color: var(--accent-green); }
.text-muted  { color: var(--text-muted); }
.text-center { text-align: center; }
.mt-4 { margin-block-start: var(--space-4); }
.mt-8 { margin-block-start: var(--space-8); }
.mb-4 { margin-block-end: var(--space-4); }
.gap-4 { gap: var(--space-4); }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.w-full { width: 100%; }

/* ---- Dashboard ---- */
.dashboard-shell {
  display: grid;
  gap: clamp(1.5rem, 2vw, 2.5rem);
  font-family: var(--font-dashboard-body);
}

.dashboard-hero,
.dashboard-panel,
.dashboard-complete-banner {
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(132, 234, 248, 0.18);
  border-radius: 28px;
  background:
    linear-gradient(155deg, rgba(11, 25, 31, 0.94), rgba(16, 37, 46, 0.96)),
    oklch(0.22 0.03 202);
  box-shadow: 0 28px 70px rgba(2, 10, 14, 0.42);
}

.dashboard-hero::before,
.dashboard-panel::before,
.dashboard-complete-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at top right, rgba(255, 138, 91, 0.12), transparent 30%),
    radial-gradient(circle at left 20%, rgba(90, 227, 255, 0.14), transparent 32%);
}

.dashboard-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(280px, 0.95fr);
  gap: clamp(1.25rem, 2vw, 2rem);
  padding: clamp(1.5rem, 2.5vw, 2.5rem);
}

.dashboard-hero__copy,
.dashboard-hero__status,
.dashboard-panel > *,
.dashboard-complete-banner > * {
  position: relative;
  z-index: 1;
}

.dashboard-hero__copy {
  display: grid;
  align-content: start;
  gap: 1rem;
}

.dashboard-hero__eyebrow,
.dashboard-section-head p,
.dashboard-level-track__meta,
.dashboard-module__progress-row,
.dashboard-module__cta,
.dashboard-badge__body span,
.dashboard-empty-state p {
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: oklch(0.79 0.04 200);
}

.dashboard-hero__title,
.dashboard-section-head h2,
.dashboard-module__title,
.dashboard-progress-crest__value,
.dashboard-metric__value,
.dashboard-complete-banner h2 {
  font-family: var(--font-dashboard-display);
  font-variant-numeric: tabular-nums;
}

.dashboard-hero__title {
  font-size: clamp(2.3rem, 4vw, 4.7rem);
  line-height: 0.95;
  letter-spacing: 0.02em;
  max-width: 11ch;
  text-wrap: balance;
}

.dashboard-hero__lede {
  max-width: 54ch;
  margin: 0;
  color: oklch(0.88 0.02 196);
  font-size: 1.05rem;
  line-height: 1.7;
}

.dashboard-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  padding-top: 0.5rem;
}

.dashboard-hero__primary,
.dashboard-hero__secondary {
  min-height: 46px;
}

.dashboard-hero__secondary {
  border: 1px solid rgba(132, 234, 248, 0.2);
  border-radius: 999px;
  padding-inline: 1rem;
  background: rgba(11, 26, 33, 0.72);
}

.dashboard-hero__secondary:hover {
  transform: translateY(-1px);
}

.dashboard-hero__status {
  display: grid;
  gap: 1rem;
  align-content: start;
}

.dashboard-progress-crest {
  display: grid;
  gap: 0.35rem;
  padding: 1.1rem 1.15rem;
  border-radius: 24px;
  background: linear-gradient(145deg, rgba(12, 31, 38, 0.92), rgba(17, 39, 51, 0.8));
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.dashboard-progress-crest__value {
  font-size: clamp(3.1rem, 5vw, 4.8rem);
  line-height: 0.9;
  color: var(--accent-green);
}

.dashboard-progress-crest__value span {
  font-size: 0.38em;
  color: oklch(0.86 0.04 197);
  margin-inline-start: 0.12em;
}

.dashboard-progress-crest__label {
  color: var(--text-secondary);
  font-size: var(--text-sm);
}

.dashboard-metrics-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
}

.dashboard-metric {
  padding: 1rem;
  border-radius: 20px;
  background: rgba(9, 24, 30, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.06);
  min-height: 110px;
  display: grid;
  align-content: end;
  gap: 0.45rem;
}

.dashboard-metric__value {
  font-size: clamp(1.4rem, 3vw, 2.2rem);
  line-height: 1;
  color: oklch(0.92 0.05 192);
}

.dashboard-metric__label {
  color: var(--text-secondary);
  font-size: 0.82rem;
  line-height: 1.5;
}

.dashboard-level-track {
  padding: 1rem 1.15rem 1.15rem;
  border-radius: 22px;
  background: rgba(7, 18, 24, 0.72);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.dashboard-level-track__meta {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.7rem;
}

.dashboard-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.18fr) minmax(290px, 0.82fr);
  gap: clamp(1.25rem, 2vw, 2rem);
  align-items: start;
}

.dashboard-panel {
  padding: clamp(1.2rem, 2vw, 1.75rem);
}

.dashboard-panel--modules {
  min-height: 100%;
}

.dashboard-section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.dashboard-section-head h2 {
  font-size: clamp(1.3rem, 2vw, 1.8rem);
  margin: 0;
  color: oklch(0.95 0.04 190);
}

.dashboard-section-head p {
  margin: 0.35rem 0 0;
  letter-spacing: 0.05em;
  text-transform: none;
}

.dashboard-modules {
  display: grid;
  gap: 1rem;
}

.dashboard-module {
  display: grid;
  gap: 0.9rem;
  padding: 1.15rem;
  border-radius: 24px;
  border: 1px solid color-mix(in oklab, var(--module-accent) 30%, transparent);
  background:
    linear-gradient(140deg, color-mix(in oklab, var(--module-accent) 8%, rgba(9, 21, 27, 0.96)), rgba(11, 27, 34, 0.88));
  color: var(--text-primary);
  text-decoration: none;
  transition: transform 220ms var(--ease-out-quart), border-color 220ms var(--ease-out-quart), box-shadow 220ms var(--ease-out-quart);
  animation: dashboard-rise 520ms var(--ease-out-expo) both;
  animation-delay: calc(var(--i, 0) * 70ms);
}

.dashboard-module:hover {
  transform: translateY(-4px);
  border-color: color-mix(in oklab, var(--module-accent) 68%, white 10%);
  box-shadow: 0 20px 36px rgba(0, 0, 0, 0.22);
}

.dashboard-module__top {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.9rem;
  align-items: start;
}

.dashboard-module__index {
  width: 3.3rem;
  min-height: 3.3rem;
  border-radius: 18px;
  display: grid;
  place-items: center;
  background: color-mix(in oklab, var(--module-accent) 18%, rgba(255, 255, 255, 0.03));
  color: color-mix(in oklab, var(--module-accent) 82%, white 6%);
  font-family: var(--font-dashboard-display);
  font-size: 1.1rem;
  letter-spacing: 0.12em;
}

.dashboard-module__heading {
  min-width: 0;
}

.dashboard-module__title {
  margin: 0;
  font-size: clamp(1.15rem, 2vw, 1.55rem);
  line-height: 1.05;
  color: oklch(0.95 0.03 190);
}

.dashboard-module__desc {
  margin: 0.45rem 0 0;
  color: color-mix(in oklab, var(--text-secondary) 84%, white 8%);
  line-height: 1.65;
  max-width: 62ch;
}

.dashboard-module__progress-row,
.dashboard-module__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.dashboard-module__progress-row {
  text-transform: none;
  letter-spacing: 0.03em;
}

.dashboard-module__bar {
  width: 100%;
  height: 0.55rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  overflow: hidden;
}

.dashboard-module__bar-fill {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, color-mix(in oklab, var(--module-accent) 85%, white 10%), color-mix(in oklab, var(--module-accent) 65%, var(--accent-blue) 35%));
}

.dashboard-module__status,
.dashboard-module__cta {
  font-size: var(--text-sm);
  line-height: 1.4;
}

.dashboard-module__status {
  color: var(--text-secondary);
  max-width: 24ch;
}

.dashboard-module__status.is-complete {
  color: var(--accent-green);
}

.dashboard-module__cta {
  color: color-mix(in oklab, var(--module-accent) 86%, white 8%);
  flex-shrink: 0;
}

.dashboard-rail {
  display: grid;
  gap: clamp(1.25rem, 2vw, 2rem);
}

.dashboard-badges-list {
  display: grid;
  gap: 0.8rem;
}

.dashboard-badge {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.9rem;
  align-items: center;
  padding: 0.9rem 1rem;
  border-radius: 18px;
  background: rgba(8, 20, 26, 0.72);
  border: 1px solid rgba(255, 255, 255, 0.06);
  animation: dashboard-rise 420ms var(--ease-out-expo) both;
  animation-delay: calc(var(--i, 0) * 60ms);
}

.dashboard-badge img {
  display: block;
}

.dashboard-badge__body {
  display: grid;
  gap: 0.2rem;
  min-width: 0;
}

.dashboard-badge__body strong {
  font-size: 0.98rem;
  color: oklch(0.94 0.03 190);
}

.dashboard-badge__body span {
  text-transform: none;
  letter-spacing: 0.02em;
  line-height: 1.5;
}

.dashboard-empty-state {
  display: grid;
  gap: 1rem;
  justify-items: start;
  padding: 1rem 0 0.25rem;
}

.dashboard-empty-state p {
  margin: 0;
  text-transform: none;
  letter-spacing: 0.02em;
  max-width: 34ch;
}

.dashboard-leaderboard {
  overflow-x: auto;
}

.dashboard-leaderboard .leaderboard-table th,
.dashboard-leaderboard .leaderboard-table td {
  padding-block: 0.85rem;
}

.dashboard-complete-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.2rem 1.4rem;
}

.dashboard-complete-banner h2 {
  margin: 0 0 0.35rem;
  font-size: clamp(1.15rem, 2vw, 1.7rem);
  color: var(--accent-green);
}

.dashboard-complete-banner p {
  margin: 0;
  color: var(--text-secondary);
}

@keyframes dashboard-rise {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---- Responsive ---- */
@media (max-width: 980px) {
  .dashboard-hero,
  .dashboard-grid {
    grid-template-columns: 1fr;
  }

  .dashboard-hero__title {
    max-width: 15ch;
  }

  .dashboard-complete-banner {
    align-items: start;
    flex-direction: column;
  }
}

@media (max-width: 768px) {
  #sidebar {
    transform: translateX(-100%);
  }
  [dir="rtl"] #sidebar {
    transform: translateX(100%);
  }
  #sidebar.is-open {
    transform: translateX(0);
  }
  #main {
    margin-inline-start: 0;
    padding: var(--space-5);
    padding-block-start: calc(var(--space-12) + env(safe-area-inset-top, 0px));
  }

  .toast-container {
    inset-inline: var(--space-3);
    inset-block-end: var(--space-4);
    align-items: stretch;
  }

  .toast,
  .toast-badge {
    max-width: none;
  }

  .dashboard-hero,
  .dashboard-panel {
    border-radius: 24px;
  }

  .dashboard-metrics-grid {
    grid-template-columns: 1fr 1fr;
  }

  .dashboard-module__footer {
    align-items: start;
    flex-direction: column;
  }
}

@media (max-width: 480px) {
  #main { padding: var(--space-3); }
  h1 { font-size: var(--text-2xl); }
  h2 { font-size: var(--text-xl); }

  .dashboard-hero {
    padding: 1.1rem;
  }

  .dashboard-hero__title {
    font-size: clamp(1.9rem, 9vw, 3rem);
  }

  .dashboard-metrics-grid {
    grid-template-columns: 1fr;
  }

  .dashboard-module__top,
  .dashboard-badge {
    grid-template-columns: 1fr;
  }

  .dashboard-module__index {
    width: 2.8rem;
    min-height: 2.8rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .dashboard-module,
  .dashboard-badge,
  #main,
  #main .card,
  #main .lesson-content,
  #main .quiz-form,
  .toast,
  .toast-badge,
  .module-shell,
  .lesson-shell {
    animation: none !important;
    transition-duration: 0.01ms !important;
  }

  .dashboard-module:hover,
  .dashboard-hero__secondary:hover {
    transform: none;
  }
}

/* ===================== MODULE VIEW ===================== */

.module-shell {
  --module-accent: var(--accent-green);
  max-width: 860px;
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  animation: dashboard-rise 0.45s var(--ease-out-quart) both;
}

.module-back {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-dashboard-body, var(--font-body));
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.18s;
  padding-block-end: var(--space-2);
}
.module-back:hover { color: var(--module-accent); }
.module-back svg { transition: transform 0.18s; }
.module-back:hover svg { transform: translateX(-3px); }

.module-hero {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  position: relative;
  overflow: hidden;
}
.module-hero::before {
  content: '';
  position: absolute;
  inset-block-start: 0;
  inset-inline-start: 0;
  width: 4px;
  inset-block-end: 0;
  background: var(--module-accent);
  border-radius: var(--radius-full) 0 0 var(--radius-full);
}
.module-hero__inner {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}
.module-hero__copy { flex: 1; min-width: 0; }
.module-hero__eyebrow {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--module-accent);
  margin: 0 0 var(--space-2);
}
.module-hero__title {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-3xl);
  font-weight: 800;
  line-height: 1.1;
  color: var(--text-primary);
  margin: 0 0 var(--space-3);
}
.module-hero__desc {
  font-family: var(--font-dashboard-body, var(--font-body));
  font-size: var(--text-sm);
  color: var(--text-muted);
  margin: 0;
  max-width: 52ch;
  line-height: 1.6;
}
.module-hero__stat {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}
.module-progress-ring {
  width: 72px;
  height: 72px;
  transform: rotate(-90deg);
}
.module-progress-ring__track {
  fill: none;
  stroke: var(--bg-elevated);
  stroke-width: 6;
}
.module-progress-ring__fill {
  fill: none;
  stroke: var(--module-accent);
  stroke-width: 6;
  stroke-linecap: round;
  transition: stroke-dashoffset 0.6s var(--ease-out-quart);
}
.module-hero__stat-label {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-top: var(--space-1);
}
.module-hero__stat-pct {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-lg);
  font-weight: 800;
  color: var(--module-accent);
  line-height: 1;
}
.module-hero__stat-sub {
  font-size: 0.625rem;
  color: var(--text-muted);
  white-space: nowrap;
  letter-spacing: 0.04em;
}

.module-lessons-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}
.module-section-head {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin: 0 0 var(--space-4);
}
.module-lessons-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.module-lesson-row {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  background: var(--bg-elevated);
  border: 1px solid transparent;
  text-decoration: none;
  color: var(--text-primary);
  transition: border-color 0.18s, background 0.18s, transform 0.18s;
}
.module-lesson-row:hover {
  border-color: var(--module-accent);
  background: color-mix(in oklab, var(--module-accent) 6%, var(--bg-elevated));
  transform: translateX(3px);
}
.module-lesson-row:focus-visible {
  outline: 2px solid var(--module-accent);
  outline-offset: 2px;
}
.module-lesson-row__num {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  background: var(--bg-primary);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-xs);
  font-weight: 700;
  color: var(--text-muted);
  transition: background 0.18s, color 0.18s, border-color 0.18s;
}
.module-lesson-row--done .module-lesson-row__num {
  background: color-mix(in oklab, var(--module-accent) 20%, transparent);
  border-color: var(--module-accent);
  color: var(--module-accent);
}
.module-lesson-row__body {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.module-lesson-row__title {
  font-family: var(--font-dashboard-body, var(--font-body));
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.module-lesson-row--done .module-lesson-row__title { color: var(--text-muted); }
.module-lesson-row__score {
  font-size: 0.65rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}
.module-lesson-row__arrow {
  color: var(--text-muted);
  flex-shrink: 0;
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity 0.18s, transform 0.18s;
}
.module-lesson-row:hover .module-lesson-row__arrow {
  opacity: 1;
  transform: translateX(0);
}

.module-quiz-cta {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}
.module-quiz-cta__copy { flex: 1; }
.module-quiz-cta__label {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-base);
  font-weight: 700;
  color: var(--text-primary);
  margin: 0 0 4px;
}
.module-quiz-cta__hint {
  font-size: var(--text-xs);
  color: var(--text-muted);
  margin: 0;
}
.module-quiz-cta__btn {
  flex-shrink: 0;
  background: var(--module-accent);
  color: var(--text-inverse);
  border: none;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-md);
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: opacity 0.18s, transform 0.15s;
}
.module-quiz-cta__btn:hover { opacity: 0.88; transform: translateY(-1px); }
.module-quiz-cta__btn:focus-visible {
  outline: 2px solid var(--module-accent);
  outline-offset: 3px;
}

@media (max-width: 640px) {
  .module-hero { padding: var(--space-5); }
  .module-hero__inner { flex-direction: column; align-items: flex-start; gap: var(--space-4); }
  .module-hero__stat { flex-direction: row; }
  .module-hero__title { font-size: var(--text-2xl); }
  .module-quiz-cta { flex-direction: column; align-items: flex-start; gap: var(--space-4); }
  .module-quiz-cta__btn { align-self: stretch; text-align: center; }
}

@media (prefers-reduced-motion: reduce) {
  .module-shell { animation: none; }
  .module-progress-ring__fill { transition: none; }
}

/* ===================== LESSON VIEW ===================== */

.lesson-shell {
  --module-accent: var(--accent-green);
  max-width: 820px;
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  animation: dashboard-rise 0.4s var(--ease-out-quart) both;
}

.lesson-breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}
.lesson-breadcrumb__crumb {
  font-size: var(--text-xs);
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.18s;
}
.lesson-breadcrumb__crumb:hover { color: var(--module-accent); }
.lesson-breadcrumb__sep {
  font-size: var(--text-xs);
  color: var(--border-subtle);
}
.lesson-breadcrumb__current {
  font-size: var(--text-xs);
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 28ch;
}

.lesson-header {
  padding-block-end: var(--space-4);
  border-block-end: 1px solid var(--border-subtle);
}
.lesson-header__meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-block-end: var(--space-3);
}
.lesson-header__index {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--module-accent);
}
.lesson-header__badge {
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 3px var(--space-2);
  border-radius: var(--radius-full);
  background: color-mix(in oklab, var(--accent-green) 18%, transparent);
  color: var(--accent-green);
  border: 1px solid color-mix(in oklab, var(--accent-green) 35%, transparent);
}
.lesson-header__title {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: clamp(var(--text-2xl), 3.5vw, var(--text-4xl));
  font-weight: 800;
  line-height: 1.1;
  color: var(--text-primary);
  margin: 0;
  letter-spacing: -0.01em;
}

.lesson-shell .lesson-content {
  font-family: var(--font-dashboard-body, var(--font-body));
  font-size: var(--text-base);
  line-height: 1.75;
  color: var(--text-secondary);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  max-width: 70ch;
}
.lesson-shell .lesson-content > *:first-child { margin-block-start: 0; }
.lesson-shell .lesson-content > *:last-child  { margin-block-end: 0; }
.lesson-shell .lesson-content h2,
.lesson-shell .lesson-content h3 {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-weight: 700;
  color: var(--text-primary);
  margin-block: var(--space-6) var(--space-3);
}
.lesson-shell .lesson-content h2 { font-size: var(--text-xl); }
.lesson-shell .lesson-content h3 { font-size: var(--text-lg); }
.lesson-shell .lesson-content strong { color: var(--text-primary); font-weight: var(--font-semibold); }
.lesson-shell .lesson-content code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  padding: 2px 5px;
  border-radius: 4px;
  background: var(--bg-elevated);
  color: var(--module-accent);
}
.lesson-shell .lesson-content ul,
.lesson-shell .lesson-content ol { padding-inline-start: var(--space-6); }
.lesson-shell .lesson-content li { margin-block: var(--space-2); }

.lesson-tool-cta {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  background: color-mix(in oklab, var(--module-accent) 6%, var(--bg-card));
  border: 1px solid color-mix(in oklab, var(--module-accent) 25%, transparent);
  border-radius: var(--radius-xl);
  padding: var(--space-5) var(--space-6);
}
.lesson-tool-cta__icon { font-size: var(--text-2xl); flex-shrink: 0; opacity: 0.7; }
.lesson-tool-cta__copy { flex: 1; }
.lesson-tool-cta__label {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-weight: 700;
  font-size: var(--text-sm);
  color: var(--text-primary);
  margin: 0 0 3px;
}
.lesson-tool-cta__hint { font-size: var(--text-xs); color: var(--text-muted); margin: 0; }
.lesson-tool-cta__btn {
  flex-shrink: 0;
  background: var(--module-accent);
  color: var(--text-inverse);
  border: none;
  padding: var(--space-2) var(--space-5);
  border-radius: var(--radius-md);
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-sm);
  font-weight: 700;
  text-decoration: none;
  transition: opacity 0.18s, transform 0.15s;
  display: inline-flex;
  align-items: center;
}
.lesson-tool-cta__btn:hover { opacity: 0.85; transform: translateY(-1px); }
.lesson-tool-cta__btn:focus-visible {
  outline: 2px solid var(--module-accent);
  outline-offset: 3px;
}

.lesson-quiz-area { min-height: var(--space-8); }
.lesson-quiz-btn {
  background: var(--module-accent);
  color: var(--text-inverse);
  border: none;
  padding: var(--space-3) var(--space-8);
  border-radius: var(--radius-md);
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: opacity 0.18s, transform 0.15s;
}
.lesson-quiz-btn:hover { opacity: 0.85; transform: translateY(-2px); }
.lesson-quiz-btn:focus-visible {
  outline: 2px solid var(--module-accent);
  outline-offset: 3px;
}

.lesson-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-block-start: var(--space-4);
  border-block-start: 1px solid var(--border-subtle);
  flex-wrap: wrap;
}
.lesson-footer__actions { display: flex; align-items: center; gap: var(--space-3); }
.lesson-footer__nav { display: flex; align-items: center; gap: var(--space-3); }
.lesson-footer__complete {
  background: transparent;
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  padding: var(--space-2) var(--space-5);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  cursor: pointer;
  transition: border-color 0.18s, color 0.18s;
}
.lesson-footer__complete:hover {
  border-color: var(--module-accent);
  color: var(--module-accent);
}
.lesson-footer__complete:focus-visible {
  outline: 2px solid var(--module-accent);
  outline-offset: 2px;
}
.lesson-footer__done-chip {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 4px var(--space-3);
  border-radius: var(--radius-full);
  background: color-mix(in oklab, var(--accent-green) 15%, transparent);
  color: var(--accent-green);
  border: 1px solid color-mix(in oklab, var(--accent-green) 30%, transparent);
}
.lesson-footer__prev,
.lesson-footer__next,
.lesson-footer__module {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  text-decoration: none;
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  transition: border-color 0.18s, color 0.18s, background 0.18s;
}
.lesson-footer__prev:hover,
.lesson-footer__module:hover {
  color: var(--text-primary);
  background: var(--bg-elevated);
}
.lesson-footer__next {
  background: var(--module-accent);
  border-color: transparent;
  color: var(--text-inverse);
  font-weight: 700;
}
.lesson-footer__next:hover { opacity: 0.88; }
.lesson-footer__next:focus-visible,
.lesson-footer__prev:focus-visible,
.lesson-footer__module:focus-visible {
  outline: 2px solid var(--module-accent);
  outline-offset: 2px;
}

@media (max-width: 640px) {
  .lesson-shell .lesson-content { padding: var(--space-5); }
  .lesson-header__title { font-size: var(--text-2xl); }
  .lesson-tool-cta { flex-wrap: wrap; }
  .lesson-tool-cta__btn { align-self: stretch; text-align: center; justify-content: center; }
  .lesson-footer { flex-direction: column; align-items: stretch; }
  .lesson-footer__nav { justify-content: flex-end; }
}

@media (prefers-reduced-motion: reduce) {
  .lesson-shell { animation: none; }
}

/* ===================== DASHBOARD INSTRUCTOR ===================== */

.dashboard-instructor {
  margin-block-start: var(--space-8);
  background: linear-gradient(135deg, rgba(23,52,65,0.92), rgba(19,39,48,0.94));
  border: 1px solid rgba(90,227,255,0.22);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-md);
}

.dashboard-instructor__header {
  margin-block-end: var(--space-5);
}

.dashboard-instructor__eyebrow {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--accent-blue);
  margin: 0 0 var(--space-1);
}

.dashboard-instructor__title {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: clamp(var(--text-xl), 2.3vw, var(--text-3xl));
  margin: 0;
}

.dashboard-instructor__grid {
  display: grid;
  grid-template-columns: minmax(180px, 220px) 1fr;
  gap: var(--space-6);
  align-items: start;
}

.dashboard-instructor__media {
  margin: 0;
}

.dashboard-instructor__photo,
.dashboard-instructor__fallback {
  width: 100%;
  aspect-ratio: 4 / 5;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(90,227,255,0.3);
  background: linear-gradient(145deg, rgba(90,227,255,0.1), rgba(200,255,34,0.14));
}

.dashboard-instructor__photo {
  object-fit: cover;
  display: block;
}

.dashboard-instructor__fallback {
  display: grid;
  place-items: center;
}

.dashboard-instructor__fallback span {
  font-family: var(--font-dashboard-display, var(--font-display));
  font-size: clamp(var(--text-xl), 5vw, 2.25rem);
  font-weight: 700;
  color: var(--text-primary);
}

.dashboard-instructor__name {
  margin-block-start: var(--space-3);
  color: var(--accent-green);
  font-weight: var(--font-semibold);
  font-size: var(--text-sm);
}

.dashboard-instructor__content {
  min-width: 0;
}

.dashboard-instructor__quote {
  margin: 0 0 var(--space-4);
  padding: var(--space-4);
  border: 1px solid rgba(200,255,34,0.35);
  background: color-mix(in oklab, var(--accent-green) 8%, transparent);
  border-radius: var(--radius-md);
}

.dashboard-instructor__quote p {
  margin: 0 0 var(--space-2);
  color: var(--text-primary);
  font-weight: var(--font-medium);
}

.dashboard-instructor__quote cite {
  color: var(--text-muted);
  font-style: normal;
  font-size: var(--text-xs);
}

.dashboard-instructor__bio p {
  color: var(--text-secondary);
  margin-block-end: var(--space-3);
  overflow-wrap: anywhere;
}

.dashboard-instructor__highlights {
  margin-block: var(--space-4);
  padding-inline-start: var(--space-5);
}

.dashboard-instructor__highlights li {
  color: var(--text-secondary);
  margin-block-end: var(--space-2);
}

.dashboard-instructor__links {
  margin-block-start: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.dashboard-instructor__links-label {
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

.dashboard-instructor__links-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

.instructor-link {
  border: 1px solid rgba(90,227,255,0.32);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  color: var(--text-primary);
  background: rgba(90,227,255,0.08);
  transition: border-color var(--transition-fast), background var(--transition-fast), color var(--transition-fast);
}

.instructor-link:hover {
  border-color: var(--accent-green);
  background: rgba(200,255,34,0.12);
  color: var(--text-primary);
}

.instructor-link:focus-visible {
  outline: 2px solid rgba(200, 255, 34, 0.92);
  outline-offset: 2px;
}

@media (max-width: 900px) {
  .dashboard-instructor__grid {
    grid-template-columns: 1fr;
  }

  .dashboard-instructor__media {
    max-width: 240px;
  }
}

@media (max-width: 640px) {
  .dashboard-instructor {
    padding: var(--space-5);
  }

  .dashboard-instructor__links-list {
    flex-direction: column;
  }

  .instructor-link {
    width: 100%;
    text-align: center;
  }
}
