/* Shared stylesheet for all lessons and reference sheets.
   Tufte-inspired: serif body, narrow measure, sidenotes in the margin on wide screens. */

:root {
  --bg: #fffff8;
  --fg: #1d1d1b;
  --muted: #6b6b66;
  --rule: #d9d6c8;
  --accent: #a3341c;       /* brick red, used sparingly */
  --accent-soft: #f5e6df;
  --ok: #2f6b3a;
  --ok-soft: #e3efe3;
  --warn: #8a5a00;
  --warn-soft: #f6ecd6;
  --panel: #f6f4ea;
  --bar: #c9c3ab;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #1b1a17; --fg: #ebe8de; --muted: #a39f92; --rule: #3a3832;
    --accent: #e0805f; --accent-soft: #3a2620; --ok: #8fc79a; --ok-soft: #1f3123;
    --warn: #e3b55c; --warn-soft: #3a2f1a; --panel: #24221e; --bar: #5b5748;
  }
}

* { box-sizing: border-box; }

html { font-size: 18px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--serif);
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

.page {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2rem 16px 4rem;
}

/* Main text column leaves room for sidenotes on the right. */
.page > * { max-width: 40rem; }
@media (min-width: 1000px) {
  .page { padding-left: 4rem; }
}

/* ---------- Header / nav ---------- */
.course-nav {
  font-family: var(--sans);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex; flex-wrap: wrap; gap: 0.25rem 1.25rem;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 0.6rem;
  margin-bottom: 2.5rem;
}
.course-nav a { color: var(--muted); text-decoration: none; }
.course-nav a:hover { color: var(--accent); }

.kicker {
  font-family: var(--sans);
  font-size: 0.8rem;
  color: var(--accent);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin: 0 0 0.4rem;
}
h1 { font-size: 2.2rem; line-height: 1.15; font-weight: 400; margin: 0 0 0.8rem; }
h2 { font-size: 1.4rem; font-weight: 400; font-style: italic; margin: 2.6rem 0 0.6rem; }
h3 { font-size: 1.05rem; font-weight: 600; margin: 1.6rem 0 0.4rem; }
p, li { hyphens: auto; }
a { color: var(--accent); text-underline-offset: 2px; }
code, kbd { font-family: var(--mono); font-size: 0.85em; background: var(--panel); padding: 0.05em 0.3em; border-radius: 3px; }

.lede { font-size: 1.15rem; color: var(--muted); }

/* The single tangible win of a lesson. */
.goal {
  border-left: 3px solid var(--accent);
  padding: 0.3rem 0 0.3rem 1rem;
  margin: 1.6rem 0;
  font-style: italic;
}
.meta { font-family: var(--sans); font-size: 0.8rem; color: var(--muted); }

/* ---------- Sidenotes (Tufte-style) ---------- */
.sidenote {
  display: block;
  font-family: var(--sans);
  font-size: 0.75rem;
  line-height: 1.45;
  color: var(--muted);
  margin: 0.4rem 0 0.8rem;
  padding-left: 0.8rem;
  border-left: 1px solid var(--rule);
}
@media (min-width: 1000px) {
  .has-notes { position: relative; }
  .sidenote {
    float: right;
    clear: right;
    width: 16rem;
    margin-right: -19rem;
    margin-top: 0.2rem;
    border-left: none;
    padding-left: 0;
  }
}

/* ---------- Blocks ---------- */
.callout {
  background: var(--panel);
  border-radius: 6px;
  padding: 1rem 1.2rem;
  margin: 1.4rem 0;
}
.callout > :first-child { margin-top: 0; }
.callout > :last-child { margin-bottom: 0; }
.callout.classroom { border-left: 4px solid var(--ok); }
.callout.ask { border-left: 4px solid var(--accent); }
.callout-title { font-family: var(--sans); font-size: 0.8rem; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase; margin-bottom: 0.4rem; }

.token {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.85em;
  padding: 0.05em 0.35em;
  margin: 0 1px;
  border-radius: 3px;
  background: var(--accent-soft);
  white-space: pre;
}

.source {
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: 1rem 0;
  margin: 2rem 0;
}
.source strong { font-weight: 600; }

footer.lesson-footer {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--rule);
  font-family: var(--sans);
  font-size: 0.85rem;
  color: var(--muted);
}
footer.lesson-footer a { margin-right: 1rem; }

/* ---------- Interactive widgets (shared look) ---------- */
.widget {
  font-family: var(--sans);
  font-size: 0.9rem;
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 1rem 1.1rem 1.1rem;
  margin: 1.6rem 0;
  background: var(--bg);
}
.widget-title { font-weight: 600; margin-bottom: 0.2rem; }
.widget-hint { color: var(--muted); font-size: 0.8rem; margin-bottom: 0.8rem; }

button {
  font: inherit;
  font-family: var(--sans);
  font-size: 0.85rem;
  border: 1px solid var(--fg);
  background: transparent;
  color: var(--fg);
  border-radius: 999px;
  padding: 0.35rem 0.95rem;
  cursor: pointer;
}
button:hover { background: var(--fg); color: var(--bg); }
button:disabled { opacity: 0.4; cursor: default; background: transparent; color: var(--fg); }
button.primary { background: var(--fg); color: var(--bg); }

input[type="number"], input[type="text"] {
  font: inherit;
  width: 4.5rem;
  padding: 0.25rem 0.4rem;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--bg);
  color: var(--fg);
}

.feedback { margin-top: 0.7rem; padding: 0.55rem 0.8rem; border-radius: 6px; font-size: 0.85rem; }
.feedback.ok { background: var(--ok-soft); color: var(--ok); }
.feedback.no { background: var(--warn-soft); color: var(--warn); }

/* Next-token widget */
.nt-context { font-family: var(--serif); font-size: 1.1rem; margin-bottom: 0.8rem; }
.nt-context .nt-out { color: var(--accent); }
.nt-row { display: grid; grid-template-columns: 6.5rem 1fr 3rem; align-items: center; gap: 0.6rem; margin: 0.2rem 0; }
.nt-label { font-family: var(--mono); font-size: 0.85rem; white-space: pre; overflow: hidden; text-overflow: ellipsis; }
.nt-track { height: 0.8rem; background: var(--panel); border-radius: 2px; overflow: hidden; }
.nt-fill { height: 100%; background: var(--bar); transition: background 0.2s; }
.nt-row.hit .nt-fill { background: var(--accent); }
.nt-pct { text-align: right; font-variant-numeric: tabular-nums; color: var(--muted); font-size: 0.8rem; }
.nt-actions { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 0.9rem; }
.nt-log { margin-top: 0.8rem; font-size: 0.82rem; color: var(--muted); }
.nt-log ol { margin: 0.3rem 0 0; padding-left: 1.4rem; }

/* Mini-training widget */
.mt-label { font-size: 0.75rem; letter-spacing: 0.04em; text-transform: uppercase; color: var(--muted); margin: 0.9rem 0 0.3rem; }
.mt-corpus { margin: 0; padding-left: 1.4rem; font-family: var(--serif); font-size: 0.95rem; color: var(--muted); }
.mt-corpus li.learned { color: var(--fg); }
.mt-corpus li.learned::marker { color: var(--accent); }
.mt-add { display: flex; gap: 0.5rem; margin-top: 0.8rem; }
.mt-add input[type="text"] { flex: 1; width: auto; min-width: 0; }

/* Scoring simulator */
.ss-controls { display: grid; gap: 0.8rem; margin: 0.4rem 0 0.6rem; }
.ss-slider { display: grid; gap: 0.2rem; }
.ss-slider-top { display: flex; justify-content: space-between; gap: 1rem; font-size: 0.85rem; }
.ss-val { color: var(--accent); font-variant-numeric: tabular-nums; }
.ss-slider input[type="range"] { width: 100%; accent-color: var(--accent); }
.ss-table { margin-top: 0.8rem; font-variant-numeric: tabular-nums; }
.ss-table td.ss-name { font-weight: 500; }
.ss-table td.ss-bad { color: var(--warn); }
.ss-table td.ss-score { font-weight: 700; }

/* Sorter */
.so-list { margin: 0.4rem 0 0; padding-left: 1.4rem; }
.so-item { margin: 0 0 1rem; }
.so-text { font-family: var(--serif); font-size: 1rem; margin-bottom: 0.4rem; }
.so-buttons { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.so-btn.right { border-color: var(--ok); background: var(--ok-soft); color: var(--ok); opacity: 1; }
.so-btn.wrong { border-color: var(--warn); background: var(--warn-soft); color: var(--warn); opacity: 1; }

/* Preference rater */
.pr-pair { margin: 1rem 0 1.4rem; }
.pr-count { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted); }
.pr-prompt { font-family: var(--serif); font-size: 1rem; font-style: italic; margin: 0.2rem 0 0.6rem; }
.pr-answers { display: grid; grid-template-columns: 1fr; gap: 0.6rem; }
@media (min-width: 640px) { .pr-answers { grid-template-columns: 1fr 1fr; } }
.pr-answer {
  display: flex; flex-direction: column; gap: 0.3rem; text-align: left;
  border-radius: 8px; border-color: var(--rule); padding: 0.7rem 0.9rem; line-height: 1.45;
}
.pr-answer:hover { background: var(--panel); color: var(--fg); }
.pr-answer:disabled { opacity: 0.55; }
.pr-answer.chosen { opacity: 1; border-color: var(--accent); background: var(--accent-soft); color: var(--fg); }
.pr-label { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted); }
.pr-text { font-family: var(--serif); font-size: 0.95rem; }
.pr-summary { border-top: 1px solid var(--rule); padding-top: 0.8rem; margin-top: 0.8rem; }
.nt-row .pr-trait { font-family: var(--sans); white-space: normal; font-size: 0.8rem; }
.pr-summary .nt-row { grid-template-columns: 11rem 1fr 3rem; }
.pr-note { font-size: 0.88rem; margin: 0.8rem 0 0; }

/* Layer stack diagram */
.stack { display: grid; gap: 0.35rem; margin: 1.4rem 0; font-family: var(--sans); font-size: 0.85rem; }
.stack-layer { border: 1px solid var(--rule); border-left: 4px solid var(--bar); border-radius: 6px; padding: 0.6rem 0.9rem; background: var(--bg); }
.stack-layer strong { display: block; font-size: 0.9rem; }
.stack-layer span { color: var(--muted); }
.stack-layer.l3 { border-left-color: var(--accent); }
.stack-layer.l2 { border-left-color: var(--warn); }
.stack-layer.l1 { border-left-color: var(--ok); }

/* Prompt checker */
.pk-input {
  width: 100%; font-family: var(--mono); font-size: 0.82rem; line-height: 1.5;
  padding: 0.6rem 0.7rem; border: 1px solid var(--rule); border-radius: 6px;
  background: var(--bg); color: var(--fg); resize: vertical;
}
.pk-list { list-style: none; padding: 0; margin: 0.9rem 0 0; display: grid; gap: 0.35rem; }
.pk-list li { display: flex; gap: 0.5rem; align-items: baseline; }
.pk-mark { width: 1rem; flex: none; text-align: center; }
.pk-ok .pk-mark { color: var(--ok); font-weight: 700; }
.pk-miss .pk-mark { color: var(--muted); }
.pk-tip { color: var(--muted); }
.pk-example { margin-top: 0.9rem; }
.pk-example summary { cursor: pointer; color: var(--accent); }
.pk-pre { white-space: pre-wrap; font-family: var(--mono); font-size: 0.78rem; background: var(--panel); padding: 0.8rem; border-radius: 6px; margin: 0.6rem 0 0; }

/* 2x2 quadrant diagram */
.quad { display: grid; grid-template-columns: auto 1fr 1fr; grid-template-rows: auto 1fr 1fr; gap: 0.4rem; margin: 1.4rem 0; font-family: var(--sans); font-size: 0.82rem; }
.quad-axis { color: var(--muted); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.04em; display: flex; align-items: center; justify-content: center; text-align: center; padding: 0.2rem; }
.quad-axis.row { writing-mode: vertical-rl; transform: rotate(180deg); }
.quad-cell { border-radius: 6px; padding: 0.7rem 0.8rem; border: 1px solid var(--rule); }
.quad-cell strong { display: block; font-size: 0.9rem; margin-bottom: 0.2rem; }
.quad-cell span { color: var(--muted); }
.quad-cell.good { background: var(--ok-soft); border-color: var(--ok); }
.quad-cell.short { background: var(--panel); }
.quad-cell.danger { background: var(--warn-soft); border-color: var(--warn); }
.quad-cell.check { background: var(--accent-soft); border-color: var(--accent); }

/* Mission checklist */
.mission-check { list-style: none; padding: 0; }
.mission-check li { padding: 0.5rem 0; border-bottom: 1px solid var(--rule); }
.mission-check li::before { content: "☐ "; color: var(--accent); }

/* Table of contents for longer lessons */
.toc { font-family: var(--sans); font-size: 0.85rem; margin: 1.4rem 0; padding: 0.8rem 1rem; border: 1px solid var(--rule); border-radius: 6px; }
.toc ol { margin: 0.3rem 0 0; padding-left: 1.3rem; }
.toc a { color: var(--fg); text-decoration: none; }
.toc a:hover { color: var(--accent); }

/* Comparison table in text */
.data-table { width: 100%; border-collapse: collapse; font-family: var(--sans); font-size: 0.85rem; margin: 1rem 0; font-variant-numeric: tabular-nums; }
.data-table th, .data-table td { text-align: right; padding: 0.35rem 0.5rem; border-bottom: 1px solid var(--rule); }
.data-table th:first-child, .data-table td:first-child { text-align: left; }
.data-table th { font-weight: 500; color: var(--muted); }
.data-table caption { caption-side: bottom; text-align: left; color: var(--muted); font-size: 0.75rem; padding-top: 0.4rem; }

/* Myth / fact pairs */
.myth { margin: 0.8rem 0; }
.myth dt { font-style: italic; color: var(--muted); }
.myth dt::before { content: "Mythos: "; font-style: normal; font-family: var(--sans); font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--warn); }
.myth dd { margin: 0.2rem 0 0.8rem 0; }

/* Warm-up recall (spaced retrieval from earlier lessons) */
.recall summary { cursor: pointer; font-family: var(--sans); font-size: 0.85rem; color: var(--accent); }

/* Predict-then-check widget */
.pc-table { width: 100%; border-collapse: collapse; }
.pc-table th { text-align: left; font-weight: 500; color: var(--muted); font-size: 0.78rem; padding: 0.3rem 0.4rem; border-bottom: 1px solid var(--rule); }
.pc-table td { padding: 0.45rem 0.4rem; border-bottom: 1px solid var(--rule); vertical-align: middle; }
.pc-table td.pc-item { font-family: var(--mono); }
.pc-result { font-size: 0.8rem; }
.pc-step { margin: 0.4rem 0 0.8rem; }

/* Quiz widget */
.quiz-q { margin: 1.1rem 0 0.4rem; font-weight: 500; }
.quiz-q .num { color: var(--muted); margin-right: 0.3rem; }
.quiz-opts { display: grid; gap: 0.4rem; }
.quiz-opt {
  text-align: left;
  border-radius: 6px;
  border-color: var(--rule);
  padding: 0.55rem 0.8rem;
  line-height: 1.35;
}
.quiz-opt:hover { background: var(--panel); color: var(--fg); }
.quiz-opt.wrong { border-color: var(--warn); background: var(--warn-soft); color: var(--warn); }
.quiz-opt.right { border-color: var(--ok); background: var(--ok-soft); color: var(--ok); }
.quiz-score { margin-top: 1.2rem; font-weight: 600; }
.quiz-locked { opacity: 0.35; pointer-events: none; }

/* ---------- Reference sheets ---------- */
.ref-grid { display: grid; grid-template-columns: 1fr; gap: 1rem 2rem; }
@media (min-width: 760px) { .ref-grid { grid-template-columns: 1fr 1fr; } }
.ref-card { border-top: 2px solid var(--fg); padding-top: 0.5rem; }
.ref-card h3 { margin-top: 0; }
body.reference .page > * { max-width: 52rem; }

/* ---------- Print ---------- */
@media print {
  :root { --bg: #fff; --fg: #000; }
  html { font-size: 11pt; }
  .course-nav, .widget, .no-print { display: none !important; }
  .page { padding: 0; }
  .page > * { max-width: none; }
  .sidenote { float: none; width: auto; margin: 0.2rem 0 0.6rem; }
  a { color: inherit; }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: 0.8em; color: #555; }
  .ref-card { break-inside: avoid; }
}