/* Shared stylesheet for all lessons and reference documents.
   Tufte-influenced: generous margins, sparse rules, sidenotes, print-first. */

:root {
  --ink: #16130f;
  --ink-soft: #5c554c;
  --ink-faint: #8b8378;
  --rule: #ddd6cb;
  --paper: #fffcf7;
  --paper-alt: #f6f1e8;
  --accent: #7a3b2e;
  --accent-soft: #f0e2dd;
  --good: #2f6b4f;
  --warn: #8a5a10;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

body {
  font-family: var(--serif);
  color: var(--ink);
  background: var(--paper);
  font-size: 19px;
  line-height: 1.62;
  margin: 0;
  padding: 4rem 1.5rem 8rem;
  -webkit-font-smoothing: antialiased;
}

.page { max-width: 43rem; margin: 0 auto; }

/* ---- Masthead ---- */
.masthead { border-bottom: 2px solid var(--ink); padding-bottom: 1.1rem; margin-bottom: 2.6rem; }
.eyebrow {
  font-family: var(--sans); font-size: 0.66rem; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--accent); font-weight: 650; margin: 0 0 0.7rem;
}
h1 { font-size: 2.35rem; line-height: 1.14; margin: 0 0 0.5rem; font-weight: 600; letter-spacing: -0.015em; }
.standfirst { font-size: 1.08rem; color: var(--ink-soft); font-style: italic; margin: 0; }

h2 {
  font-size: 1.4rem; font-weight: 600; margin: 3rem 0 0.9rem;
  letter-spacing: -0.01em; line-height: 1.25;
}
h3 { font-family: var(--sans); font-size: 0.95rem; font-weight: 650; margin: 2rem 0 0.6rem; letter-spacing: -0.005em; }
p { margin: 0 0 1.1rem; }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 2px; }
strong { font-weight: 650; }
ul, ol { padding-left: 1.3rem; margin: 0 0 1.2rem; }
li { margin-bottom: 0.45rem; }
hr { border: 0; border-top: 1px solid var(--rule); margin: 2.6rem 0; }

/* ---- Sidenote / aside ---- */
.note {
  font-family: var(--sans); font-size: 0.85rem; line-height: 1.55;
  color: var(--ink-soft); border-left: 2px solid var(--rule);
  padding: 0.1rem 0 0.1rem 1rem; margin: 1.5rem 0;
}

/* ---- Callouts ---- */
.callout {
  border: 1px solid var(--rule); border-left: 4px solid var(--accent);
  background: var(--paper-alt); padding: 1.1rem 1.3rem; margin: 1.8rem 0; border-radius: 3px;
}
.callout p:last-child { margin-bottom: 0; }
.callout .label {
  font-family: var(--sans); font-size: 0.66rem; letter-spacing: 0.14em; text-transform: uppercase;
  font-weight: 650; color: var(--accent); display: block; margin-bottom: 0.45rem;
}
.callout.act { border-left-color: var(--good); }
.callout.act .label { color: var(--good); }
.callout.warn { border-left-color: var(--warn); }
.callout.warn .label { color: var(--warn); }

/* ---- Key figure ---- */
.figure-strip { display: flex; gap: 1.5rem; flex-wrap: wrap; margin: 1.8rem 0; }
.figure-strip .fig { flex: 1 1 8rem; }
.figure-strip .num { font-size: 2rem; font-weight: 600; line-height: 1.1; letter-spacing: -0.02em; }
.figure-strip .cap { font-family: var(--sans); font-size: 0.78rem; color: var(--ink-soft); line-height: 1.4; }

/* ---- Tables ---- */
table { width: 100%; border-collapse: collapse; margin: 1.6rem 0; font-size: 0.92rem; }
thead th {
  font-family: var(--sans); font-size: 0.68rem; letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--ink-faint); font-weight: 650; text-align: left;
  border-bottom: 1.5px solid var(--ink); padding: 0 0.7rem 0.5rem 0;
}
tbody td { padding: 0.55rem 0.7rem 0.55rem 0; border-bottom: 1px solid var(--rule); vertical-align: top; }
tbody tr:last-child td { border-bottom: none; }
td.wk { font-family: var(--mono); font-size: 0.85rem; white-space: nowrap; color: var(--accent); }

/* ---- Timeline ---- */
.timeline { list-style: none; padding: 0; margin: 1.8rem 0; border-left: 2px solid var(--rule); }
.timeline li { position: relative; padding: 0 0 1.3rem 1.6rem; margin: 0; }
.timeline li::before {
  content: ""; position: absolute; left: -5px; top: 0.55rem;
  width: 8px; height: 8px; border-radius: 50%; background: var(--accent);
}
.timeline .when {
  font-family: var(--sans); font-size: 0.7rem; letter-spacing: 0.09em; text-transform: uppercase;
  color: var(--ink-faint); font-weight: 650; display: block;
}
.timeline .what { font-weight: 600; }
.timeline .why { font-size: 0.92rem; color: var(--ink-soft); display: block; }

/* ---- Footer ---- */
.lesson-footer {
  margin-top: 4rem; padding-top: 1.4rem; border-top: 2px solid var(--ink);
  font-family: var(--sans); font-size: 0.88rem; color: var(--ink-soft);
}
.lesson-footer h3 { margin-top: 0; }
.ask { background: var(--accent-soft); border-radius: 3px; padding: 0.9rem 1.1rem; margin-top: 1.6rem; }

@media print {
  body { background: #fff; font-size: 11.5pt; padding: 0; }
  .quiz, .lesson-footer .ask { break-inside: avoid; }
  a { color: var(--ink); }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: 0.72em; color: #666; word-break: break-all; }
  .no-print { display: none !important; }
}