/* teach-workspace shared lesson stylesheet
   Tufte-ish, dark, print-friendly. Every lesson links this.
   No external dependencies. */
:root {
  --bg: #101418;
  --panel: #171c22;
  --panel2: #1d242c;
  --ink: #d8dee6;
  --muted: #8b97a5;
  --accent: #7aa2f7;
  --accent2: #9ece6a;
  --line: #2a313b;
  --code-bg: #0c0f12;
  --warn: #e0af68;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: "Inter", -apple-system, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
}
.wrap { max-width: 46rem; margin: 0 auto; padding: 2.5rem 1.25rem 6rem; }

/* header */
header.top { border-bottom: 1px solid var(--line); padding-bottom: 1.25rem; margin-bottom: 2.25rem; }
header.top .kicker { font-size: .78rem; letter-spacing: .16em; text-transform: uppercase; color: var(--accent); margin: 0 0 .35rem; }
header.top h1 { font-family: var(--serif); font-weight: 600; font-size: 2.1rem; line-height: 1.2; margin: 0; }
header.top .mission { color: var(--muted); font-size: .95rem; margin: .6rem 0 0; max-width: 40rem; }
header.top .mission a { color: var(--accent); }

/* headings */
h2 { font-family: var(--serif); font-weight: 600; font-size: 1.5rem; margin: 2.6rem 0 .75rem; padding-bottom: .3rem; border-bottom: 1px solid var(--line); }
h3 { font-size: 1.12rem; margin: 1.9rem 0 .5rem; color: #eef2f7; }
p { margin: .7rem 0; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
strong { color: #eef2f7; }
code { font-family: var(--mono); font-size: .86em; background: var(--code-bg); border: 1px solid var(--line); border-radius: 4px; padding: .08em .32em; }
pre {
  background: var(--code-bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 1rem 1.15rem;
  overflow-x: auto;
  font-size: .86rem;
  line-height: 1.55;
}
pre code { background: none; border: 0; padding: 0; font-size: 1em; }
ul, ol { padding-left: 1.4rem; }
li { margin: .35rem 0; }
li::marker { color: var(--accent); }

/* components */
.goal { background: var(--panel); border-left: 3px solid var(--accent); border-radius: 0 8px 8px 0; padding: .9rem 1.1rem; margin: 1.4rem 0; }
.goal .label { font-size: .72rem; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); font-weight: 700; }
.callout { background: var(--panel); border: 1px solid var(--line); border-left: 3px solid var(--accent2); border-radius: 0 8px 8px 0; padding: .85rem 1.05rem; margin: 1.3rem 0; font-size: .95rem; }
.callout.warn { border-left-color: var(--warn); }
.callout .label { font-size: .72rem; letter-spacing: .14em; text-transform: uppercase; font-weight: 700; color: var(--accent2); }
.callout.warn .label { color: var(--warn); }
.tight { margin: .4rem 0; }

/* quiz */
.quiz { margin: 1.6rem 0; }
.quiz .q { background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 1rem 1.2rem 1.15rem; margin: .9rem 0; }
.quiz .q p { margin: 0 0 .55rem; }
.quiz .opts { display: grid; gap: .45rem; }
.quiz button {
  text-align: left; font: inherit; font-size: .93rem;
  background: var(--panel2); color: var(--ink);
  border: 1px solid var(--line); border-radius: 7px;
  padding: .55rem .8rem; cursor: pointer; transition: border-color .12s, background .12s;
}
.quiz button:hover { border-color: var(--accent); }
.quiz button.correct { border-color: var(--accent2); background: rgba(158,206,106,.12); }
.quiz button.wrong { border-color: var(--warn); background: rgba(224,175,104,.12); }
.quiz .fb { font-size: .88rem; margin-top: .55rem; min-height: 1.2em; }
.quiz .fb.ok { color: var(--accent2); }
.quiz .fb.bad { color: var(--warn); }

/* checklist */
.check { list-style: none; padding-left: 0; }
.check li { padding-left: 1.9rem; position: relative; }
.check li::before { content: "☐"; position: absolute; left: 0; color: var(--accent); }

/* breadcrumbs + footer */
.bread { font-size: .82rem; color: var(--muted); margin-bottom: 1.4rem; }
.bread a { color: var(--muted); }
footer { margin-top: 4rem; border-top: 1px solid var(--line); padding-top: 1.2rem; font-size: .85rem; color: var(--muted); }

/* print: light, compact, ink-friendly */
@media print {
  body { background: #fff; color: #111; font-size: 11pt; }
  .wrap { max-width: 100%; padding: 0; }
  pre, .quiz, .callout, .goal { background: #f6f6f4; border-color: #ccc; }
  a { color: #111; text-decoration: underline; }
  code { background: #f0f0ec; border-color: #ddd; }
  .quiz button { display: none; } /* answers only as text feedback */
  header.top h1 { font-size: 1.6rem; }
}