/* ==========================================================================
   Top-Down Pixel Art — shared course stylesheet
   Every lesson and reference document links this file. Change it here, not
   in a lesson. Designed to read on screen (dark, bleached-western) and to
   print cleanly (light, high contrast).
   ========================================================================== */

:root {
  /* Course chrome */
  --bg:        #14110d;
  --bg-raise:  #1d1913;
  --bg-sunk:   #0d0b08;
  --rule:      #3a3128;
  --ink:       #e6dcc6;
  --ink-dim:   #a99b80;
  --ink-faint: #6f6552;

  --accent:      #c9a227; /* dust gold — headings, emphasis */
  --accent-warm: #a4442a; /* rust — warnings, breaks */
  --accent-cold: #6f8f7a; /* verdigris — correctness, the occult */

  /* The Lesson 1 value palette. Five values, deliberately near-colourless,
     so form is learned before colour. */
  --pv-bone: #f2e6cc;
  --pv-sand: #c2a578;
  --pv-clay: #8a6f4e;
  --pv-dusk: #55412d;
  --pv-ink:  #2a1f17;

  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Charter, Georgia, "Times New Roman", serif;
  --sans:  ui-sans-serif, -apple-system, "Segoe UI", Inter, Helvetica, Arial, sans-serif;
  --mono:  ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --measure: 34rem;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.62;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

/* --------------------------------------------------------------------------
   Layout: a single measure-width column with room for margin notes at
   wide viewports.
   -------------------------------------------------------------------------- */

.page {
  max-width: 62rem;
  margin: 0 auto;
  padding: 3.5rem 1.5rem 6rem;
}

.page > * { max-width: var(--measure); }

/* Elements that are allowed to break the measure. */
.page > .full,
.page > figure,
.page > .widget { max-width: 54rem; }

/* --------------------------------------------------------------------------
   Masthead
   -------------------------------------------------------------------------- */

.kicker {
  font-family: var(--sans);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 0.9rem;
}

h1 {
  font-size: clamp(2rem, 5vw, 2.9rem);
  line-height: 1.1;
  font-weight: 400;
  letter-spacing: -0.015em;
  margin: 0 0 0.6rem;
}

.subtitle {
  font-size: 1.15rem;
  color: var(--ink-dim);
  font-style: italic;
  margin: 0 0 2rem;
}

.masthead-rule {
  border: 0;
  border-top: 1px solid var(--rule);
  margin: 0 0 2.5rem;
  max-width: 54rem;
}

h2 {
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 3.2rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--rule);
  max-width: 54rem;
}

h3 {
  font-size: 1.12rem;
  font-weight: 600;
  margin: 2rem 0 0.5rem;
  color: var(--ink);
}

p { margin: 0 0 1.1rem; }

.lede {
  font-size: 1.2rem;
  line-height: 1.55;
  color: var(--ink);
}

a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid var(--accent);
  padding-bottom: 0.05em;
}
a:hover { background: rgba(201, 162, 39, 0.13); }

strong { font-weight: 700; color: #fff5e2; }
em { font-style: italic; }

code, kbd, .mono {
  font-family: var(--mono);
  font-size: 0.86em;
}

code {
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: 0.08em 0.35em;
}

kbd {
  background: var(--bg-raise);
  border: 1px solid var(--rule);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 0.1em 0.4em;
  font-size: 0.8em;
}

ul, ol { margin: 0 0 1.1rem; padding-left: 1.3rem; }
li { margin-bottom: 0.45rem; }

blockquote {
  margin: 1.6rem 0;
  padding-left: 1.1rem;
  border-left: 2px solid var(--accent);
  font-style: italic;
  color: var(--ink-dim);
}
blockquote cite {
  display: block;
  margin-top: 0.5rem;
  font-style: normal;
  font-size: 0.82rem;
  font-family: var(--sans);
  color: var(--ink-faint);
}

/* --------------------------------------------------------------------------
   Margin notes
   -------------------------------------------------------------------------- */

.sidenote {
  font-family: var(--sans);
  font-size: 0.78rem;
  line-height: 1.5;
  color: var(--ink-dim);
  border-left: 2px solid var(--rule);
  padding-left: 0.8rem;
  margin: 1.3rem 0;
}

@media (min-width: 68rem) {
  .sidenote {
    float: right;
    clear: right;
    width: 15rem;
    margin-right: -19rem;
    margin-top: 0.35rem;
    margin-bottom: 1rem;
  }
}

/* --------------------------------------------------------------------------
   Callouts
   -------------------------------------------------------------------------- */

.callout {
  background: var(--bg-raise);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--accent);
  border-radius: 2px;
  padding: 1.1rem 1.3rem;
  margin: 1.8rem 0;
}
.callout > :last-child { margin-bottom: 0; }

.callout-label {
  display: block;
  font-family: var(--sans);
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.55rem;
}

.callout.warn { border-left-color: var(--accent-warm); }
.callout.warn .callout-label { color: var(--accent-warm); }

.callout.good { border-left-color: var(--accent-cold); }
.callout.good .callout-label { color: var(--accent-cold); }

.callout.source { border-left-color: var(--ink-faint); }
.callout.source .callout-label { color: var(--ink-dim); }

/* --------------------------------------------------------------------------
   Figures & sprite display
   -------------------------------------------------------------------------- */

figure { margin: 2rem 0; }

figcaption {
  font-family: var(--sans);
  font-size: 0.76rem;
  line-height: 1.5;
  color: var(--ink-dim);
  margin-top: 0.75rem;
  max-width: var(--measure);
}

canvas { display: block; image-rendering: pixelated; }

.sprite-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem;
  align-items: flex-start;
}

.sprite-card {
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: 0.7rem;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0.55rem;
}

.sprite-card .label {
  font-family: var(--sans);
  font-size: 0.68rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--ink-dim);
  text-align: center;
}

.sprite-card.is-good { border-color: var(--accent-cold); }
.sprite-card.is-bad  { border-color: var(--accent-warm); }

.sprite-card .credit {
  font-family: var(--sans);
  font-size: 0.6rem;
  line-height: 1.4;
  color: var(--ink-faint);
  text-align: center;
  max-width: 13rem;
}

/* --------------------------------------------------------------------------
   Palette swatches
   -------------------------------------------------------------------------- */

.swatches {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 1.4rem 0;
  padding: 0;
  list-style: none;
}

.swatches li {
  margin: 0;
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--ink-dim);
  text-align: center;
}

.swatches .chip {
  display: block;
  width: 4.4rem;
  height: 2.6rem;
  border: 1px solid var(--rule);
  border-radius: 2px;
  margin-bottom: 0.35rem;
}

/* --------------------------------------------------------------------------
   Tables
   -------------------------------------------------------------------------- */

table {
  border-collapse: collapse;
  width: 100%;
  max-width: 54rem;
  margin: 1.6rem 0;
  font-family: var(--sans);
  font-size: 0.85rem;
}

th, td {
  text-align: left;
  padding: 0.55rem 0.8rem 0.55rem 0;
  border-bottom: 1px solid var(--rule);
  vertical-align: top;
}

th {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  border-bottom-color: var(--ink-faint);
}

/* --------------------------------------------------------------------------
   Widgets (quiz / editor share this shell)
   -------------------------------------------------------------------------- */

.widget {
  background: var(--bg-raise);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: 1.4rem;
  margin: 2rem 0;
}

.widget-title {
  font-family: var(--sans);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 0.9rem;
}

/* --------------------------------------------------------------------------
   Glossary
   -------------------------------------------------------------------------- */

.gloss { margin: 1.6rem 0; max-width: 54rem; }

.gloss dt {
  font-family: var(--sans);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--accent);
  margin-top: 1.5rem;
  scroll-margin-top: 2rem;
}
.gloss dt .aka {
  font-weight: 400;
  font-style: italic;
  color: var(--ink-faint);
  font-size: 0.82rem;
}

.gloss dd {
  margin: 0.3rem 0 0;
  padding-left: 0;
  max-width: var(--measure);
}
.gloss dd .cite {
  display: block;
  font-family: var(--sans);
  font-size: 0.72rem;
  color: var(--ink-faint);
  margin-top: 0.3rem;
}

.gloss-index {
  font-family: var(--sans);
  font-size: 0.78rem;
  line-height: 2;
  color: var(--ink-dim);
  max-width: 54rem;
  margin-bottom: 1rem;
}
.gloss-index a { border-bottom-color: var(--rule); }

/* --------------------------------------------------------------------------
   Quiz widget (quiz.js)
   -------------------------------------------------------------------------- */

.quiz-intro {
  font-size: 0.95rem;
  color: var(--ink-dim);
  margin-bottom: 1rem;
}

.quiz-progress {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-bottom: 1.2rem;
}

.quiz-dot {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--rule);
}
.quiz-dot.done { background: var(--accent-cold); }
.quiz-dot.current { background: var(--accent); }

.quiz-count {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--ink-faint);
}

.quiz-stage {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1.2rem;
}

.quiz-vs {
  font-family: var(--sans);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

.quiz-prompt {
  font-size: 1.02rem;
  margin-bottom: 1rem;
}

.quiz-options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
  gap: 0.6rem;
}

.quiz-option {
  font-family: var(--sans);
  font-size: 0.88rem;
  padding: 0.75rem 0.9rem;
  text-align: left;
  color: var(--ink);
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: 3px;
  cursor: pointer;
  transition: border-color 0.12s, background 0.12s;
}
.quiz-option:hover:not(:disabled) {
  border-color: var(--accent);
  background: rgba(201, 162, 39, 0.07);
}
.quiz-option:disabled { cursor: default; opacity: 0.55; }
.quiz-option.is-correct {
  opacity: 1;
  border-color: var(--accent-cold);
  background: rgba(111, 143, 122, 0.16);
}
.quiz-option.is-wrong {
  opacity: 1;
  border-color: var(--accent-warm);
  background: rgba(164, 68, 42, 0.16);
}

.quiz-feedback {
  margin-top: 1.1rem;
  padding: 0.9rem 1.05rem;
  border-radius: 3px;
  border: 1px solid var(--rule);
  border-left-width: 3px;
  font-size: 0.92rem;
  background: var(--bg-sunk);
}
.quiz-feedback.good { border-left-color: var(--accent-cold); }
.quiz-feedback.bad  { border-left-color: var(--accent-warm); }

.quiz-verdict-tag {
  display: block;
  font-family: var(--sans);
  font-size: 0.64rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.45rem;
  color: var(--ink-dim);
}
.quiz-feedback.good .quiz-verdict-tag { color: var(--accent-cold); }
.quiz-feedback.bad  .quiz-verdict-tag { color: var(--accent-warm); }

.quiz-btn {
  margin-top: 1.1rem;
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.6rem 1.2rem;
  color: var(--bg);
  background: var(--accent);
  border: 0;
  border-radius: 3px;
  cursor: pointer;
}
.quiz-btn:hover { filter: brightness(1.12); }

.quiz-summary { text-align: left; }
.quiz-score {
  font-family: var(--mono);
  font-size: 2.4rem;
  color: var(--accent);
  margin: 0 0 0.4rem;
}
.quiz-verdict { color: var(--ink-dim); margin-bottom: 0; }

/* --------------------------------------------------------------------------
   Pixel editor (pixel-editor.js)
   -------------------------------------------------------------------------- */

.editor-brief {
  font-size: 0.95rem;
  color: var(--ink-dim);
  margin-bottom: 1.3rem;
  max-width: var(--measure);
}
.editor-brief strong { color: var(--ink); }

.editor-layout {
  display: flex;
  flex-wrap: wrap;
  gap: 1.6rem;
  align-items: flex-start;
}

.editor-stage {
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: 0.5rem;
}

.editor-canvas {
  cursor: crosshair;
  touch-action: none;
  display: block;
}

.editor-side {
  flex: 1 1 15rem;
  min-width: 14rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.editor-label {
  font-family: var(--sans);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-top: 0.7rem;
}
.editor-label:first-child { margin-top: 0; }
.editor-label-block { margin-top: 1.6rem; }

.editor-palette { display: flex; gap: 0.35rem; }

.editor-swatch {
  width: 2.2rem;
  height: 2.2rem;
  border: 2px solid transparent;
  border-radius: 3px;
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.4);
  cursor: pointer;
  padding: 0;
}
.editor-swatch.active {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.editor-swatch-name {
  font-family: var(--sans);
  font-size: 0.7rem;
  color: var(--ink-dim);
  min-height: 1.2em;
}

.editor-tools { display: flex; flex-wrap: wrap; gap: 0.35rem; }

.editor-tool {
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  padding: 0.42rem 0.7rem;
  color: var(--ink-dim);
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: 3px;
  cursor: pointer;
}
.editor-tool:hover { color: var(--ink); border-color: var(--ink-faint); }
.editor-tool.active {
  color: var(--bg);
  background: var(--accent);
  border-color: var(--accent);
}
.editor-tool.peek:active {
  color: var(--bg);
  background: var(--accent-cold);
}

.editor-previews {
  display: flex;
  align-items: flex-end;
  gap: 0.9rem;
  padding: 0.5rem 0.6rem;
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: 3px;
  width: fit-content;
}
.editor-preview, .editor-scene {
  image-rendering: pixelated;
  display: block;
}
.editor-scene {
  border: 1px solid var(--rule);
  border-radius: 3px;
  max-width: 100%;
}

.editor-checks {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-width: 54rem;
}

.check {
  display: flex;
  gap: 0.7rem;
  align-items: flex-start;
  padding: 0.6rem 0.8rem;
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-left-width: 3px;
  border-radius: 3px;
}
.check.pass { border-left-color: var(--accent-cold); }
.check.fail { border-left-color: var(--rule); }

.check-mark {
  font-family: var(--mono);
  font-size: 1rem;
  line-height: 1.3;
  color: var(--ink-faint);
  width: 1rem;
  flex: none;
  text-align: center;
}
.check.pass .check-mark { color: var(--accent-cold); }

.check-label {
  font-family: var(--sans);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--ink);
}
.check.fail .check-label { color: var(--ink-dim); }

.check-note {
  font-family: var(--sans);
  font-size: 0.75rem;
  line-height: 1.5;
  color: var(--ink-faint);
  margin-top: 0.15rem;
}

.check-tally {
  font-family: var(--sans);
  font-size: 0.78rem;
  color: var(--ink-dim);
  padding-top: 0.3rem;
}
.check-tally.all { color: var(--accent-cold); font-weight: 600; }

/* --------------------------------------------------------------------------
   Navigation / footer
   -------------------------------------------------------------------------- */

.course-nav {
  margin-top: 4rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--rule);
  font-family: var(--sans);
  font-size: 0.8rem;
  color: var(--ink-dim);
  max-width: 54rem;
}

.course-nav ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.6rem;
}
.course-nav li { margin: 0; }

.ask-teacher {
  margin-top: 2.4rem;
  padding: 1rem 1.2rem;
  border: 1px dashed var(--rule);
  border-radius: 3px;
  font-family: var(--sans);
  font-size: 0.84rem;
  color: var(--ink-dim);
  max-width: 54rem;
}
.ask-teacher strong { color: var(--accent); }

/* --------------------------------------------------------------------------
   Print — flip to a light, ink-frugal document
   -------------------------------------------------------------------------- */

@media print {
  :root {
    --bg: #fff; --bg-raise: #fff; --bg-sunk: #fff;
    --rule: #ccc; --ink: #111; --ink-dim: #555; --ink-faint: #888;
    --accent: #7a5c00; --accent-warm: #8a2c14; --accent-cold: #2f5c42;
  }
  body { font-size: 11pt; }
  .page { padding: 0; max-width: none; }
  a { border-bottom: none; text-decoration: underline; }
  .widget, .callout, .sprite-card { break-inside: avoid; }
  .no-print { display: none !important; }
  h2 { break-after: avoid; }
}