/* Mug's Code Forge — V0.3
   ---------------------------------------------------------------- */

:root {
  /* warm forge palette, refined */
  --bg:        oklch(0.18 0.018 55);
  --bg-deep:   oklch(0.14 0.018 55);
  --panel:     oklch(0.22 0.020 55);
  --panel-2:   oklch(0.26 0.022 55);
  --line:      oklch(0.30 0.020 55 / 0.55);
  --line-soft: oklch(0.30 0.020 55 / 0.28);

  --ink:       oklch(0.96 0.018 75);
  --ink-soft:  oklch(0.82 0.024 70);
  --muted:     oklch(0.66 0.028 65);

  --ember:     oklch(0.74 0.165 55);
  --ember-hi:  oklch(0.86 0.110 75);
  --ember-deep:oklch(0.55 0.150 45);

  --good:      oklch(0.80 0.130 150);
  --bad:       oklch(0.72 0.150 25);
  --info:      oklch(0.78 0.110 230);

  --radius:    18px;
  --radius-sm: 12px;
  --radius-pill: 999px;
  --shadow-lg: 0 30px 60px -20px rgba(0,0,0,0.5), 0 8px 20px -8px rgba(0,0,0,0.35);
  --shadow-md: 0 12px 30px -10px rgba(0,0,0,0.45);

  --font-sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --safe-t: env(safe-area-inset-top, 0px);
  --safe-b: env(safe-area-inset-bottom, 0px);
  --safe-l: env(safe-area-inset-left, 0px);
  --safe-r: env(safe-area-inset-right, 0px);
}

* { box-sizing: border-box; }
*:focus-visible { outline: 2px solid var(--ember); outline-offset: 2px; border-radius: 6px; }

html, body { height: 100%; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  color: var(--ink);
  background:
    radial-gradient(60rem 40rem at 8% -10%, oklch(0.74 0.165 55 / 0.16), transparent 60%),
    radial-gradient(50rem 36rem at 110% 110%, oklch(0.74 0.165 30 / 0.10), transparent 60%),
    linear-gradient(180deg, var(--bg-deep), var(--bg));
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  -webkit-tap-highlight-color: transparent;
  padding-left: var(--safe-l);
  padding-right: var(--safe-r);
}

/* Type ------------------------------------------------------------- */
h1, h2, h3, h4 { margin: 0; font-weight: 650; letter-spacing: -0.02em; line-height: 1.15; }
h1 { font-size: clamp(1.6rem, 3.4vw, 2.2rem); letter-spacing: -0.035em; }
h2 { font-size: clamp(1.45rem, 3vw, 2rem); letter-spacing: -0.03em; }
h3 { font-size: 1.05rem; letter-spacing: -0.01em; }
p  { margin: 0 0 0.85rem; }
p:last-child { margin-bottom: 0; }
a  { color: var(--ember-hi); text-decoration: none; border-bottom: 1px solid transparent; }
a:hover { border-bottom-color: currentColor; }
code { font-family: var(--font-mono); font-size: 0.92em; padding: 0.08em 0.35em; background: oklch(0.96 0.018 75 / 0.07); border-radius: 4px; color: var(--ember-hi); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--ember-hi);
  margin: 0 0 0.5rem;
}

/* Buttons ---------------------------------------------------------- */
button {
  font: inherit;
  font-weight: 600;
  border: 0;
  border-radius: var(--radius-pill);
  padding: 0.75rem 1.1rem;
  min-height: 44px;
  background: linear-gradient(180deg, var(--ember), var(--ember-deep));
  color: oklch(0.16 0.02 55);
  cursor: pointer;
  box-shadow: 0 1px 0 oklch(0.92 0.08 75 / 0.4) inset, 0 8px 20px -8px var(--ember-deep);
  transition: transform 120ms ease, box-shadow 160ms ease, opacity 160ms ease, background 160ms ease;
  touch-action: manipulation;
  user-select: none;
  -webkit-user-select: none;
  white-space: nowrap;
}
button:hover { transform: translateY(-1px); }
button:active { transform: translateY(0); }
button:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }
button.ghost {
  background: transparent;
  color: var(--ink);
  box-shadow: none;
  border: 1px solid var(--line);
}
button.ghost:hover { background: oklch(0.96 0.018 75 / 0.05); }

/* App shell -------------------------------------------------------- */
.app-shell {
  width: min(1320px, 100%);
  margin: 0 auto;
  padding: max(0.75rem, var(--safe-t)) clamp(0.75rem, 2vw, 1.25rem) max(1rem, var(--safe-b));
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.5rem 0.25rem 0.85rem;
}

.brand { display: flex; align-items: center; gap: 0.75rem; }
.brand-mark {
  width: 38px; height: 38px;
  border-radius: 10px;
  background: radial-gradient(circle at 30% 30%, var(--ember-hi), var(--ember) 45%, var(--ember-deep) 100%);
  box-shadow: 0 0 0 1px oklch(0.92 0.08 75 / 0.2) inset, 0 8px 20px -8px var(--ember-deep);
  flex: 0 0 auto;
  display: grid; place-items: center;
  font-family: var(--font-mono);
  font-weight: 700;
  color: oklch(0.16 0.02 55);
  font-size: 1.1rem;
}
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text .eyebrow { margin: 0; font-size: 0.68rem; }
.brand-text h1 { font-size: 1.05rem; letter-spacing: -0.02em; font-weight: 600; }

.version-pill {
  flex: 0 0 auto;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  padding: 0.45rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--ember-hi);
  background: oklch(0.96 0.018 75 / 0.04);
}

/* Tabs ------------------------------------------------------------- */
.tabs {
  display: flex;
  gap: 0.35rem;
  padding: 0.4rem;
  margin-bottom: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: oklch(0.22 0.020 55 / 0.7);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}
.tabs::-webkit-scrollbar { display: none; }

.tab {
  flex: 1 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  background: transparent;
  color: var(--ink-soft);
  box-shadow: none;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.9rem;
  font-weight: 600;
  font-size: 0.92rem;
  min-height: 44px;
  white-space: nowrap;
}
.tab:hover { background: oklch(0.96 0.018 75 / 0.05); color: var(--ink); }
.tab[aria-selected="true"] {
  background: oklch(0.74 0.165 55 / 0.15);
  color: var(--ember-hi);
  border-color: oklch(0.74 0.165 55 / 0.35);
}
.tab-icon { font-size: 1rem; line-height: 1; }

/* Views ------------------------------------------------------------ */
.view[hidden] { display: none; }
.view-header {
  padding: 0.25rem 0.25rem 0.75rem;
  max-width: 70ch;
}
.view-header h2 { margin-bottom: 0.5rem; }

/* Layout ----------------------------------------------------------- */
.layout {
  display: grid;
  grid-template-columns: 290px minmax(0, 1fr);
  gap: 1rem;
  align-items: start;
}

.sidebar, .content-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: oklch(0.22 0.020 55 / 0.7);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: var(--shadow-md);
}

.sidebar {
  position: sticky;
  top: calc(var(--safe-t) + 0.5rem);
  padding: 0.7rem;
  max-height: calc(100vh - 1rem - var(--safe-t) - var(--safe-b));
  overflow: auto;
  overscroll-behavior: contain;
}

.mobile-nav-toggle { display: none; width: 100%; margin-bottom: 0.6rem; }

.lesson-nav { display: grid; gap: 0.25rem; }

.nav-item {
  display: grid;
  grid-template-columns: 1.85rem 1fr auto;
  align-items: center;
  gap: 0.55rem;
  width: 100%;
  padding: 0.55rem 0.65rem;
  min-height: 44px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--ink);
  background: transparent;
  box-shadow: none;
  text-align: left;
  font-weight: 500;
}
.nav-item:hover { background: oklch(0.96 0.018 75 / 0.04); }
.nav-item.active {
  background: oklch(0.74 0.165 55 / 0.10);
  border-color: oklch(0.74 0.165 55 / 0.35);
}

.nav-number {
  display: inline-grid;
  place-items: center;
  width: 1.75rem; height: 1.75rem;
  border-radius: 50%;
  background: oklch(0.96 0.018 75 / 0.06);
  color: var(--ink-soft);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  border: 1px solid var(--line-soft);
}
.nav-item.active .nav-number {
  background: oklch(0.74 0.165 55 / 0.18);
  color: var(--ember-hi);
  border-color: oklch(0.74 0.165 55 / 0.4);
}
.nav-item.done .nav-number {
  background: oklch(0.80 0.130 150 / 0.15);
  color: var(--good);
  border-color: oklch(0.80 0.130 150 / 0.35);
}
.nav-title { font-size: 0.85rem; letter-spacing: -0.005em; }
.nav-check { color: var(--good); font-weight: 700; }

/* Content panel ---------------------------------------------------- */
.content-panel { padding: clamp(0.85rem, 2vw, 1.25rem); display: grid; gap: 1rem; }
.content-panel.wide { /* used outside lessons */
  padding: clamp(1rem, 2.4vw, 1.5rem);
}

.hero-card {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 1.25rem;
  padding: clamp(1rem, 2.4vw, 1.5rem);
  align-items: end;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: oklch(0.26 0.022 55 / 0.55);
}
.hero-card .lesson-meta { min-width: 0; }
.subtitle { color: var(--ink-soft); line-height: 1.55; max-width: 60ch; }

.progress-wrap { min-width: min(240px, 100%); }
.progress-label {
  display: flex; justify-content: space-between; align-items: baseline;
  margin-bottom: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--muted);
  text-transform: uppercase;
}
.progress-label strong { color: var(--ember-hi); font-weight: 600; font-size: 0.95rem; }
.progress-bar {
  position: relative;
  height: 0.55rem;
  border-radius: var(--radius-pill);
  background: oklch(0.96 0.018 75 / 0.08);
  overflow: hidden;
}
.progress-bar span {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--ember), var(--ember-hi));
  transition: width 600ms cubic-bezier(0.22, 1, 0.36, 1);
  box-shadow: 0 0 16px oklch(0.74 0.165 55 / 0.5);
}

.lesson-body {
  padding: clamp(1rem, 2.4vw, 1.5rem);
  line-height: 1.6;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: oklch(0.22 0.020 55 / 0.5);
}
.lesson-body p + p { margin-top: 0.85rem; }
.lesson-body strong { color: var(--ember-hi); font-weight: 600; }

.callout {
  border-left: 2px solid var(--ember);
  margin: 1rem 0;
  padding: 0.8rem 1rem;
  background: oklch(0.74 0.165 55 / 0.07);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--ink-soft);
}
.callout strong { color: var(--ember-hi); }

.code-box, .output-box {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  white-space: pre-wrap;
  overflow-x: auto;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
  padding: 0.95rem 1.05rem;
  background: var(--bg-deep);
  color: oklch(0.92 0.05 80);
  line-height: 1.55;
  margin: 0;
}

/* Practice + quiz -------------------------------------------------- */
.practice-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.practice-card, .tool-card, .resources-card, .game-card, .video-card, .glossary-item, .channel-item, .card-section {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: oklch(0.22 0.020 55 / 0.5);
  padding: clamp(0.9rem, 2vw, 1.15rem);
}

.practice-card, .tool-card, .resources-card { display: flex; flex-direction: column; gap: 0.65rem; }

.card-header { display: flex; align-items: center; justify-content: space-between; gap: 0.5rem; }
.card-header h3 { margin: 0; }
.tag {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-pill);
  padding: 0.18rem 0.55rem;
}
.tag.done { color: var(--good); border-color: oklch(0.80 0.130 150 / 0.4); background: oklch(0.80 0.130 150 / 0.08); }

textarea, input[type="text"], input[type="number"] {
  width: 100%;
  font: inherit;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg-deep);
  color: var(--ink);
  padding: 0.75rem 0.85rem;
  outline: none;
  transition: border-color 140ms ease, box-shadow 140ms ease;
}
textarea:focus, input:focus {
  border-color: oklch(0.74 0.165 55 / 0.7);
  box-shadow: 0 0 0 3px oklch(0.74 0.165 55 / 0.15);
}
textarea { min-height: 100px; resize: vertical; line-height: 1.5; }

.action-row { display: flex; gap: 0.5rem; flex-wrap: wrap; }

.feedback {
  min-height: 1.5rem;
  margin: 0;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--muted);
  transition: color 200ms ease;
}
.feedback.good { color: var(--good); }
.feedback.bad  { color: var(--bad); }

.quiz-options { display: grid; gap: 0.4rem; }
.quiz-option {
  justify-content: flex-start;
  text-align: left;
  border-radius: var(--radius-sm);
  padding: 0.75rem 0.9rem;
  background: oklch(0.96 0.018 75 / 0.04);
  color: var(--ink);
  border: 1px solid var(--line-soft);
  box-shadow: none;
  font-weight: 500;
  white-space: normal;
  line-height: 1.4;
  min-height: 48px;
}
.quiz-option:hover { background: oklch(0.96 0.018 75 / 0.07); border-color: var(--line); }
.quiz-option.correct {
  border-color: oklch(0.80 0.130 150 / 0.6);
  background: oklch(0.80 0.130 150 / 0.10);
}
.quiz-option.wrong {
  border-color: oklch(0.72 0.150 25 / 0.6);
  background: oklch(0.72 0.150 25 / 0.10);
}

/* Tool cards (calculator, plan builder) ---------------------------- */
.toolbox {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}
.calculator-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.6rem;
}
.plan-grid { display: grid; gap: 0.6rem; }
label {
  display: grid;
  gap: 0.3rem;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* Resources / Resource links --------------------------------------- */
.resource-list { display: grid; gap: 0.5rem; }
.resource-item {
  display: grid;
  gap: 0.15rem;
  padding: 0.75rem 0.9rem;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
  background: oklch(0.96 0.018 75 / 0.03);
  color: var(--ink);
  transition: border-color 140ms ease, background 140ms ease, transform 140ms ease;
}
.resource-item:hover {
  border-color: oklch(0.74 0.165 55 / 0.4);
  background: oklch(0.74 0.165 55 / 0.05);
  transform: translateY(-1px);
}
.resource-item strong { color: var(--ember-hi); font-weight: 600; font-size: 0.95rem; }
.resource-item span { color: var(--muted); font-size: 0.83rem; }

/* Footer nav ------------------------------------------------------- */
.lesson-footer {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 0.6rem;
  align-items: center;
  padding-top: 0.25rem;
}
.lesson-footer .markdone-wrap { display: flex; justify-content: center; }

/* Completion banner ------------------------------------------------ */
.completion-banner {
  display: none;
  position: relative;
  padding: 1rem 1.2rem;
  border-radius: var(--radius);
  background: linear-gradient(135deg, oklch(0.74 0.165 55 / 0.18), oklch(0.80 0.130 150 / 0.12));
  border: 1px solid oklch(0.80 0.130 150 / 0.35);
  overflow: hidden;
}
.completion-banner.show { display: block; animation: slideDown 320ms ease both; }
.completion-banner h3 { color: var(--ember-hi); margin-bottom: 0.25rem; }
.completion-banner p { color: var(--ink-soft); margin: 0; font-size: 0.92rem; }

/* ============ GAMES ============ */
.games-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}
.game-card { display: grid; gap: 0.85rem; }
.game-header {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: flex-start;
}
.game-header h3 { margin: 0 0 0.2rem; }
.game-sub { color: var(--ink-soft); font-size: 0.88rem; margin: 0; }

.score-pill {
  display: inline-flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.1rem;
  padding: 0.4rem 0.7rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-soft);
  background: oklch(0.96 0.018 75 / 0.04);
  min-width: 4.5rem;
}
.score-label {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}
.score-pill strong { color: var(--ember-hi); font-family: var(--font-mono); font-size: 1.05rem; }

.game-stage {
  display: grid;
  gap: 0.7rem;
  padding: 0.85rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-soft);
  background: oklch(0.18 0.018 55 / 0.5);
}
.game-meta {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}
.game-meta strong { color: var(--ember-hi); font-weight: 600; }

.game-prompt {
  font-size: 1.05rem;
  line-height: 1.45;
  color: var(--ink);
  padding: 0.5rem 0.1rem;
}
.game-prompt code { font-size: 0.95rem; }

.game-options {
  display: grid;
  gap: 0.5rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}
.game-option {
  font-family: var(--font-mono);
  justify-content: flex-start;
  text-align: left;
  border-radius: var(--radius-sm);
  padding: 0.85rem 0.95rem;
  background: oklch(0.96 0.018 75 / 0.04);
  color: var(--ink);
  border: 1px solid var(--line-soft);
  box-shadow: none;
  font-weight: 500;
  white-space: normal;
  line-height: 1.4;
  min-height: 52px;
}
.game-option:hover { background: oklch(0.96 0.018 75 / 0.07); border-color: var(--line); }
.game-option.correct {
  border-color: oklch(0.80 0.130 150 / 0.7);
  background: oklch(0.80 0.130 150 / 0.15);
  color: var(--good);
  animation: pop 280ms cubic-bezier(0.22, 1, 0.36, 1);
}
.game-option.wrong {
  border-color: oklch(0.72 0.150 25 / 0.7);
  background: oklch(0.72 0.150 25 / 0.12);
  color: var(--bad);
  animation: shake 320ms cubic-bezier(0.36, 0.07, 0.19, 0.97);
}
.game-option:disabled { cursor: default; opacity: 0.95; transform: none; }

.game-feedback {
  min-height: 1.5rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--ink-soft);
}
.game-feedback.good { color: var(--good); }
.game-feedback.bad { color: var(--bad); }

.game-footer { display: flex; gap: 0.5rem; flex-wrap: wrap; }

/* Code board for Spot the Bug + output snippet */
.code-board {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-soft);
  background: var(--bg-deep);
  overflow: hidden;
  display: grid;
}
.code-board.static {
  padding: 0.9rem 1rem;
  white-space: pre-wrap;
  color: oklch(0.92 0.05 80);
  line-height: 1.55;
}
.code-line {
  display: grid;
  grid-template-columns: 2.4rem 1fr;
  align-items: center;
  gap: 0.6rem;
  padding: 0.45rem 0.8rem;
  background: transparent;
  color: oklch(0.92 0.05 80);
  border: 0;
  border-top: 1px solid oklch(0.30 0.020 55 / 0.25);
  text-align: left;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  border-radius: 0;
  min-height: 0;
  box-shadow: none;
  white-space: pre;
  cursor: pointer;
  font-weight: 500;
  transition: background 120ms ease, color 120ms ease;
}
.code-line:first-child { border-top: 0; }
.code-line:hover { background: oklch(0.74 0.165 55 / 0.07); }
.code-line .ln {
  color: var(--muted);
  font-size: 0.78rem;
  text-align: right;
  user-select: none;
}
.code-line .lc { color: oklch(0.92 0.05 80); overflow-x: auto; }
.code-line.correct { background: oklch(0.80 0.130 150 / 0.16); color: var(--good); animation: pop 280ms cubic-bezier(0.22, 1, 0.36, 1); }
.code-line.wrong { background: oklch(0.72 0.150 25 / 0.14); color: var(--bad); animation: shake 320ms cubic-bezier(0.36, 0.07, 0.19, 0.97); }
.code-line.reveal { background: oklch(0.80 0.130 150 / 0.10); color: var(--good); }
.code-line:disabled { cursor: default; }

.console-reveal {
  display: grid;
  gap: 0.35rem;
  padding: 0.75rem 0.9rem;
  border-radius: var(--radius-sm);
  border: 1px solid oklch(0.78 0.110 230 / 0.35);
  background: oklch(0.78 0.110 230 / 0.07);
}
.console-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--info);
}
.console-reveal pre {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  margin: 0;
  white-space: pre-wrap;
  color: oklch(0.92 0.05 80);
}

/* ============ VIDEO LIBRARY ============ */
.card-section {
  display: grid;
  gap: 0.75rem;
  margin-top: 1rem;
}
.card-section h3 { margin: 0; }

.video-group { display: grid; gap: 0.75rem; margin-top: 0.5rem; }
.video-group + .video-group { margin-top: 1.25rem; }
.video-group-title {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  margin: 0.5rem 0 0.1rem;
}
.video-group-title h3 { margin: 0; }
.video-group-title .sub { color: var(--muted); font-size: 0.85rem; }

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

.video-card {
  display: grid;
  gap: 0.55rem;
  padding: 0;
  overflow: hidden;
}
.video-thumb {
  position: relative;
  display: block;
  aspect-ratio: 16 / 9;
  background: var(--bg-deep);
  overflow: hidden;
  border-bottom: 1px solid var(--line-soft);
}
.video-thumb img { width: 100%; height: 100%; object-fit: cover; display: block; }
.video-thumb iframe { width: 100%; height: 100%; border: 0; display: block; }
.video-play {
  position: absolute;
  inset: 0;
  display: grid; place-items: center;
  background: linear-gradient(180deg, transparent 50%, oklch(0.14 0.018 55 / 0.75));
  color: var(--ink);
  cursor: pointer;
  border: 0;
  border-radius: 0;
  box-shadow: none;
  transition: background 200ms ease;
  padding: 0;
}
.video-play:hover { background: linear-gradient(180deg, oklch(0.14 0.018 55 / 0.25) 0%, oklch(0.14 0.018 55 / 0.6) 100%); }
.video-play-icon {
  width: 56px; height: 56px;
  border-radius: 50%;
  background: oklch(0.74 0.165 55 / 0.92);
  display: grid; place-items: center;
  color: oklch(0.16 0.02 55);
  box-shadow: 0 8px 28px -6px var(--ember-deep);
}
.video-play-icon svg { width: 22px; height: 22px; transform: translateX(2px); }

.video-meta {
  padding: 0 1rem 1rem;
  display: grid;
  gap: 0.25rem;
}
.video-title { font-weight: 600; line-height: 1.25; font-size: 1rem; color: var(--ink); }
.video-channel { font-size: 0.78rem; color: var(--muted); font-family: var(--font-mono); }
.video-note { font-size: 0.85rem; color: var(--ink-soft); }
.video-actions { display: flex; gap: 0.5rem; padding: 0 1rem 1rem; }
.video-actions .ghost { font-size: 0.8rem; padding: 0.5rem 0.85rem; min-height: 36px; }

/* Channel grid ---------------------------------------------------- */
.channel-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 0.6rem;
}
.channel-item {
  display: grid;
  gap: 0.2rem;
  padding: 0.85rem 1rem;
  color: var(--ink);
  transition: border-color 140ms ease, background 140ms ease, transform 140ms ease;
}
.channel-item:hover {
  border-color: oklch(0.74 0.165 55 / 0.4);
  background: oklch(0.74 0.165 55 / 0.05);
  transform: translateY(-1px);
}
.channel-item strong { color: var(--ember-hi); font-family: var(--font-mono); font-size: 0.92rem; }
.channel-item span { font-size: 0.82rem; color: var(--muted); }

/* ============ GLOSSARY ============ */
.search-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}
.search-row input { flex: 1; font-family: var(--font-sans); }
.search-count {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
  white-space: nowrap;
}

.glossary-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 0.7rem;
}
.glossary-item {
  display: grid;
  gap: 0.35rem;
  padding: 1rem;
}
.glossary-term {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.6rem;
}
.glossary-term strong {
  font-family: var(--font-mono);
  font-size: 0.98rem;
  color: var(--ember-hi);
  letter-spacing: -0.01em;
}
.glossary-pill {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-pill);
  padding: 0.12rem 0.5rem;
}
.glossary-def { font-size: 0.92rem; color: var(--ink-soft); line-height: 1.55; }
.glossary-eg {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
  background: var(--bg-deep);
  border: 1px solid var(--line-soft);
  border-radius: 8px;
  padding: 0.45rem 0.6rem;
}
.glossary-empty {
  grid-column: 1 / -1;
  text-align: center;
  color: var(--muted);
  padding: 1.5rem;
}

/* Animations ------------------------------------------------------ */
.fade-enter { animation: fadeIn 240ms cubic-bezier(0.22, 1, 0.36, 1) both; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(6px);} to { opacity: 1; transform: translateY(0);} }
@keyframes slideDown { from { opacity: 0; transform: translateY(-8px);} to { opacity: 1; transform: translateY(0);} }
@keyframes pop { 0% { transform: scale(0.96);} 50% { transform: scale(1.04);} 100% { transform: scale(1);} }
@keyframes shake {
  10%, 90% { transform: translateX(-1px); }
  20%, 80% { transform: translateX(2px); }
  30%, 50%, 70% { transform: translateX(-4px); }
  40%, 60% { transform: translateX(4px); }
}
.pop { animation: pop 280ms cubic-bezier(0.22, 1, 0.36, 1); }

/* Mobile --------------------------------------------------------- */
@media (max-width: 920px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar {
    position: relative;
    top: 0;
    max-height: none;
    padding: 0.6rem;
  }
  .mobile-nav-toggle { display: block; min-height: 44px; }
  .lesson-nav.collapsed { display: none; }
  .hero-card { grid-template-columns: 1fr; }
  .practice-grid, .toolbox { grid-template-columns: 1fr; }
  .calculator-grid { grid-template-columns: 1fr; }
  .topbar { padding-bottom: 0.6rem; }
  .lesson-footer { grid-template-columns: 1fr 1fr; }
  .lesson-footer .markdone-wrap { grid-column: 1 / -1; order: -1; }
  .lesson-footer .markdone-wrap button { width: 100%; }
  .video-grid { grid-template-columns: 1fr; }
  .game-options { grid-template-columns: 1fr; }
  .tab-label { font-size: 0.85rem; }
}

@media (max-width: 540px) {
  .tab { padding: 0.55rem 0.7rem; font-size: 0.85rem; }
  .tab-icon { font-size: 0.95rem; }
  .game-header { flex-direction: column; }
  .score-pill { align-self: flex-start; align-items: flex-start; }
}

@media (max-width: 420px) {
  body { font-size: 15px; }
  .brand-text h1 { font-size: 0.95rem; }
  .brand-mark { width: 34px; height: 34px; }
}

/* Print ---------------------------------------------------------- */
@media print {
  body { background: #fff; color: #111; }
  .sidebar, .topbar, .tabs, .lesson-footer, .practice-grid, .resources-card, .completion-banner, .mobile-nav-toggle { display: none !important; }
  .layout, .toolbox { display: block; }
  .content-panel, .hero-card, .lesson-body, .tool-card { box-shadow: none; border-color: #ccc; background: #fff; color: #111; }
  .code-box, .output-box { background: #f6f3ee; color: #111; border-color: #ccc; }
}

/* Reduced motion ------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* V0.5 Workshop additions --------------------------------------- */
.version-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-left: 0.35rem;
  padding: 0.1rem 0.45rem;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(255,255,255,0.18);
  color: var(--ember-hi);
  font-family: var(--font-mono);
  font-size: 0.72em;
  vertical-align: middle;
}
.audit-strip {
  padding: 0.85rem 1rem;
  border: 1px solid rgba(250, 146, 72, 0.35);
  background: linear-gradient(135deg, rgba(250,146,72,0.14), rgba(255,255,255,0.035));
  border-radius: var(--radius-card);
  color: var(--ink-soft);
  margin: 0 0 1rem;
  line-height: 1.45;
}
.tool-jump-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0 0 1rem;
}
.tool-jump-row a {
  color: var(--ink);
  text-decoration: none;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-pill);
  padding: 0.42rem 0.68rem;
  background: rgba(255,255,255,0.04);
  font-size: 0.86rem;
}
.tool-jump-row a:hover { border-color: rgba(250,146,72,0.65); color: var(--ember-hi); }
.workshop-tools { grid-template-columns: repeat(auto-fit, minmax(340px, 1fr)); }
.plan-grid .span-2 { grid-column: 1 / -1; }
.storage-layout, .debug-layout {
  display: grid;
  grid-template-columns: minmax(180px, 0.8fr) minmax(280px, 1.2fr);
  gap: 0.85rem;
  align-items: start;
}
.storage-keys {
  display: grid;
  gap: 0.35rem;
  margin-top: 0.5rem;
}
.storage-key-btn {
  text-align: left;
  border: 1px solid var(--line-soft);
  background: rgba(255,255,255,0.04);
  color: var(--ink-soft);
  border-radius: 10px;
  padding: 0.5rem 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  overflow-wrap: anywhere;
}
.storage-key-btn.active, .storage-key-btn:hover {
  color: var(--ember-hi);
  border-color: rgba(250,146,72,0.65);
}
.scenario-box {
  padding: 0.85rem;
  border: 1px solid var(--line-soft);
  background: rgba(255,255,255,0.04);
  border-radius: var(--radius-card);
  color: var(--ink-soft);
  margin-bottom: 0.75rem;
  line-height: 1.45;
}
.code-board.static { min-height: 220px; white-space: pre-wrap; }
.checklist-list { display: grid; gap: 0.55rem; }
.checklist-list label {
  display: flex;
  gap: 0.5rem;
  align-items: flex-start;
  color: var(--ink-soft);
  line-height: 1.4;
}
button.danger {
  border-color: rgba(255, 99, 99, 0.45);
  color: #ffb4ad;
}
button.danger:hover { border-color: rgba(255, 99, 99, 0.85); }

@media (max-width: 920px) {
  .workshop-tools { grid-template-columns: 1fr; }
  .storage-layout, .debug-layout { grid-template-columns: 1fr; }
  .plan-grid .span-2 { grid-column: auto; }
}