/* ============================================================
   Loop Engineering — shared lesson stylesheet
   Tufte-inspired: readable serif body, generous margins,
   sidenotes, restrained palette. Prints cleanly.
   Reused by every lesson + reference doc. Edit here once.
   ============================================================ */

:root {
  --ink:        #1a1a1a;
  --ink-soft:   #555;
  --paper:      #fdfdf8;
  --rule:       #d8d4c8;
  --accent:     #9a3b2e;   /* terracotta — links, emphasis */
  --accent-2:   #2e5e9a;   /* slate blue — secondary */
  --good:       #2f6b3f;
  --bad:        #9a3b2e;
  --code-bg:    #f1efe6;
  --max-width:  46rem;
}

html { font-size: 17px; -webkit-text-size-adjust: 100%; }

body {
  font-family: Georgia, "Iowan Old Style", "Palatino Linotype", serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.55;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 4rem 1.5rem 6rem;
}

/* ---- Course identity strip ---- */
.kicker {
  font-family: -apple-system, "Segoe UI", Roboto, sans-serif;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.72rem;
  color: var(--ink-soft);
  margin-bottom: 0.4rem;
}

h1 {
  font-weight: 400;
  font-size: 2.1rem;
  line-height: 1.15;
  margin: 0 0 0.3rem;
  letter-spacing: -0.01em;
}
.subtitle {
  font-style: italic;
  color: var(--ink-soft);
  font-size: 1.1rem;
  margin: 0 0 2rem;
}

h2 {
  font-weight: 400;
  font-size: 1.4rem;
  margin: 2.6rem 0 0.6rem;
  padding-bottom: 0.25rem;
  border-bottom: 1px solid var(--rule);
}
h3 {
  font-weight: 700;
  font-size: 1.05rem;
  margin: 1.6rem 0 0.4rem;
}

p { margin: 0.7rem 0; }

a { color: var(--accent); text-decoration: none; border-bottom: 1px solid rgba(154,59,46,0.3); }
a:hover { border-bottom-color: var(--accent); }

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

blockquote {
  margin: 1.2rem 0;
  padding: 0.4rem 0 0.4rem 1.2rem;
  border-left: 3px solid var(--rule);
  color: var(--ink-soft);
  font-style: italic;
}
blockquote cite { display:block; font-style: normal; font-size: 0.85rem; margin-top: 0.4rem; }

code, pre {
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 0.86em;
}
code { background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 3px; }
pre {
  background: var(--code-bg);
  padding: 1rem 1.2rem;
  border-radius: 6px;
  overflow-x: auto;
  line-height: 1.45;
  border: 1px solid var(--rule);
}
pre code { background: none; padding: 0; }

/* ---- Sidenote / margin note ---- */
.note {
  font-size: 0.9rem;
  color: var(--ink-soft);
  background: #faf8ef;
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 0.7rem 1rem;
  margin: 1.2rem 0;
}
.note .label {
  font-family: -apple-system, "Segoe UI", sans-serif;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-size: 0.66rem;
  color: var(--accent-2);
  display: block;
  margin-bottom: 0.2rem;
}

/* ---- Citation chips ---- */
.cite {
  font-size: 0.78rem;
  font-family: -apple-system, sans-serif;
  vertical-align: super;
  line-height: 0;
}
.cite a { border: none; color: var(--accent-2); }

/* ---- Definition / key term ---- */
.term { font-variant: small-caps; letter-spacing: 0.03em; font-weight: 700; }

/* ---- "The map" grid of dimensions ---- */
.map-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
  gap: 0.8rem;
  margin: 1.4rem 0;
}
.map-card {
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 0.9rem 1rem;
  background: #fff;
}
.map-card .n {
  font-family: -apple-system, sans-serif;
  font-size: 0.72rem;
  color: var(--accent);
  letter-spacing: 0.08em;
}
.map-card h4 { margin: 0.15rem 0 0.35rem; font-size: 1rem; }
.map-card p { margin: 0; font-size: 0.9rem; color: var(--ink-soft); }

/* ---- Loop anatomy steps ---- */
ol.loop { counter-reset: step; list-style: none; padding-left: 0; }
ol.loop li {
  position: relative;
  padding: 0.5rem 0 0.5rem 2.6rem;
  border-bottom: 1px dashed var(--rule);
}
ol.loop li:last-child { border-bottom: none; }
ol.loop li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute; left: 0; top: 0.5rem;
  width: 1.7rem; height: 1.7rem;
  background: var(--accent); color: #fff;
  border-radius: 50%;
  display: grid; place-items: center;
  font-family: -apple-system, sans-serif; font-size: 0.85rem;
}

/* ---- Win box ---- */
.win {
  border: 2px solid var(--good);
  border-radius: 8px;
  padding: 1rem 1.2rem;
  margin: 2rem 0;
  background: #f3f8f3;
}
.win .label { color: var(--good); font-weight: 700; font-family: -apple-system, sans-serif; font-size: 0.8rem; letter-spacing: 0.08em; text-transform: uppercase; }

/* ---- Footer / nav ---- */
.lesson-nav {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 2px solid var(--rule);
  font-family: -apple-system, sans-serif;
  font-size: 0.9rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1.2rem;
  justify-content: space-between;
}
.ask-teacher {
  margin-top: 1.5rem;
  font-family: -apple-system, sans-serif;
  font-size: 0.92rem;
  background: #eef2f7;
  border-radius: 8px;
  padding: 0.9rem 1.1rem;
  color: var(--accent-2);
}
.ask-teacher strong { color: var(--accent-2); }

.primary-source {
  border: 1px solid var(--accent-2);
  border-radius: 8px;
  padding: 0.9rem 1.1rem;
  margin: 1.6rem 0;
  background: #f3f6fb;
}
.primary-source .label { font-family:-apple-system,sans-serif; text-transform:uppercase; letter-spacing:0.1em; font-size:0.7rem; color:var(--accent-2); }

/* ---- Quiz widget (assets/quiz.js) ---- */
.quiz { margin: 1.6rem 0; }
.quiz-score {
  font-family: -apple-system, sans-serif;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
  text-transform: uppercase;
  margin-bottom: 0.8rem;
}
.quiz-score.done { color: var(--good); font-weight: 700; }
.quiz-card {
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 0.9rem 1.1rem;
  margin: 0.8rem 0;
  background: #fff;
}
.quiz-q { margin: 0 0 0.7rem; font-size: 1.02rem; }
.quiz-q .qn { color: var(--accent); font-weight: 700; margin-right: 0.3rem; }
.quiz-opts { display: grid; gap: 0.45rem; }
.quiz-opt {
  font-family: Georgia, serif;
  font-size: 0.95rem;
  text-align: left;
  padding: 0.55rem 0.8rem;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background: var(--paper);
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s;
}
.quiz-opt:hover:not(:disabled) { background: #f1efe6; border-color: var(--ink-soft); }
.quiz-opt:disabled { cursor: default; opacity: 0.95; }
.quiz-opt.correct { border-color: var(--good); background: #eaf4ec; color: var(--good); font-weight: 700; }
.quiz-opt.wrong   { border-color: var(--bad);  background: #f7ebe9; color: var(--bad); text-decoration: line-through; }
.quiz-why {
  margin-top: 0.7rem;
  font-size: 0.9rem;
  padding: 0.5rem 0.7rem;
  border-radius: 6px;
}
.quiz-why.ok { background: #eaf4ec; color: var(--good); }
.quiz-why.no { background: #f7ebe9; color: var(--ink); }

/* ---- Language toggle bar ---- */
.langbar {
  font-family: -apple-system, "Segoe UI", sans-serif;
  font-size: 0.8rem;
  margin: -0.1rem 0 1.2rem;
}
.langbar a {
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.12rem 0.7rem;
  color: var(--accent-2);
}
.langbar a:hover { border-color: var(--accent-2); background: #f3f6fb; }

/* ---- Code sample with caption ---- */
figure.code { margin: 1.4rem 0; }
figure.code figcaption {
  font-family: -apple-system, "Segoe UI", sans-serif;
  font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--accent-2); margin-bottom: 0.35rem;
}
pre .c  { color: #8a8576; font-style: italic; }      /* comment */
pre .hl { display:block; background: #e9f1e7; margin: 0 -1.2rem; padding: 0 1.2rem; }
pre .bad-line  { display:block; background: #f6e9e7; margin: 0 -1.2rem; padding: 0 1.2rem; }

/* ---- Diagram figure (inline SVG) ---- */
figure.diagram { margin: 1.6rem 0; text-align: center; }
figure.diagram svg { max-width: 100%; height: auto; }
figure.diagram figcaption {
  font-size: 0.82rem; color: var(--ink-soft); font-style: italic; margin-top: 0.5rem;
}
.dgm-box { fill:#fff; stroke:var(--rule); }
.dgm-accent { fill:#fbeeec; stroke:var(--accent); }
.dgm-blue { fill:#eef2f7; stroke:var(--accent-2); }
.dgm-t { font-family:-apple-system,"Segoe UI",sans-serif; font-size:13px; fill:var(--ink); }
.dgm-ts { font-family:-apple-system,"Segoe UI",sans-serif; font-size:11px; fill:var(--ink-soft); }
.dgm-line { stroke:var(--ink-soft); stroke-width:1.3; fill:none; }

/* ---- Warning / anti-pattern callout ---- */
.warn {
  font-size: 0.92rem;
  background: #f9efed;
  border: 1px solid var(--bad);
  border-left: 4px solid var(--bad);
  border-radius: 6px;
  padding: 0.8rem 1.05rem;
  margin: 1.3rem 0;
  color: var(--ink);
}
.warn .label {
  font-family: -apple-system, "Segoe UI", sans-serif;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-size: 0.66rem;
  color: var(--bad);
  display: block;
  margin-bottom: 0.25rem;
  font-weight: 700;
}

/* ---- Reference / comparison table ---- */
table.ref {
  width: 100%;
  border-collapse: collapse;
  margin: 1.3rem 0;
  font-size: 0.9rem;
}
table.ref caption {
  caption-side: top;
  text-align: left;
  font-family: -apple-system, sans-serif;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-soft);
  margin-bottom: 0.4rem;
}
table.ref th, table.ref td {
  text-align: left;
  padding: 0.5rem 0.7rem;
  border-bottom: 1px solid var(--rule);
  vertical-align: top;
}
table.ref thead th {
  font-family: -apple-system, sans-serif;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-2);
  border-bottom: 2px solid var(--rule);
}
table.ref tbody th { font-weight: 700; white-space: nowrap; color: var(--accent); }
table.ref tr:last-child td, table.ref tr:last-child th { border-bottom: none; }

/* ---- Interactive checklist (assets/checklist.js) ---- */
ul.checklist { list-style: none; padding-left: 0; margin: 1.3rem 0; }
ul.checklist li {
  position: relative;
  padding: 0.55rem 0.9rem 0.55rem 2.5rem;
  border: 1px solid var(--rule);
  border-radius: 6px;
  margin: 0.45rem 0;
  background: #fff;
  cursor: pointer;
  transition: background 0.12s, opacity 0.12s;
  font-size: 0.94rem;
}
ul.checklist li:hover { border-color: var(--ink-soft); }
ul.checklist li::before {
  content: "";
  position: absolute; left: 0.75rem; top: 0.7rem;
  width: 1.1rem; height: 1.1rem;
  border: 1.5px solid var(--ink-soft);
  border-radius: 4px;
  background: var(--paper);
  display: grid; place-items: center;
  font-size: 0.8rem; line-height: 1; color: #fff;
}
ul.checklist li.done { background: #f3f8f3; border-color: var(--good); }
ul.checklist li.done::before {
  content: "✓"; background: var(--good); border-color: var(--good);
}
ul.checklist li.done .ck-task { text-decoration: line-through; color: var(--ink-soft); }
.checklist-done-msg {
  font-family: -apple-system, sans-serif; font-size: 0.85rem;
  color: var(--good); font-weight: 700; margin-top: 0.6rem; display: none;
}
.checklist-done-msg.show { display: block; }

/* ---- Print ---- */
@media print {
  body { padding: 0; max-width: none; font-size: 11pt; }
  a { color: var(--ink); border: none; }
  .ask-teacher, .lesson-nav { page-break-inside: avoid; }
  .quiz button { display: none; }
}