/* Instructor guides: plain static pages, readable on screen and printable to A4 (the PDFs are
   printed from these same pages by scripts/build-guides.mjs). */
:root {
    --ink: #0f172a;
    --muted: #475569;
    --line: #cbd5e1;
    --soft: #f1f5f9;
    --accent: #0369a1;
    --accent-soft: #e0f2fe;
    --page: #ffffff;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
    margin: 0;
    background: var(--page);
    color: var(--ink);
    font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
a { color: var(--accent); }
.bar {
    background: #0f172a;
    color: #fff;
    padding: 10px 16px;
}
.bar-inner {
    max-width: 860px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    gap: 8px 16px;
    align-items: center;
    justify-content: space-between;
}
.bar a { color: #7dd3fc; text-decoration: none; font-weight: 600; font-size: 14px; }
.bar a:hover, .bar a:focus { text-decoration: underline; }
.bar .brand { color: #fff; font-size: 16px; }
.bar nav { display: flex; flex-wrap: wrap; gap: 8px 16px; }
main { max-width: 860px; margin: 0 auto; padding: 24px 16px 48px; }
h1 { font-size: 30px; line-height: 1.2; margin: 8px 0 4px; }
h2 { font-size: 22px; margin: 36px 0 8px; padding-top: 12px; border-top: 1px solid var(--line); }
h3 { font-size: 17px; margin: 20px 0 6px; }
p { margin: 8px 0; }
ul, ol { margin: 8px 0; padding-left: 24px; }
li { margin: 3px 0; }
li > ul, li > ol { margin: 4px 0; }
.byline { color: var(--muted); font-size: 14px; margin: 0 0 16px; }
.lead { font-size: 17px; }
.note {
    background: var(--accent-soft);
    border-left: 4px solid var(--accent);
    padding: 10px 14px;
    border-radius: 4px;
    margin: 16px 0;
}
.table-wrap { overflow-x: auto; margin: 12px 0; }
table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { border: 1px solid var(--line); padding: 7px 10px; text-align: left; vertical-align: top; }
th { background: var(--soft); font-weight: 700; }
kbd {
    border: 1px solid var(--line);
    border-bottom-width: 2px;
    border-radius: 4px;
    padding: 0 5px;
    font: 600 13px/1.4 ui-monospace, Menlo, Consolas, monospace;
    background: var(--soft);
}
ul.checklist { list-style: none; padding-left: 4px; }
ul.checklist li::before { content: "\2610"; margin-right: 8px; font-size: 18px; line-height: 1; }
.toc { background: var(--soft); border-radius: 6px; padding: 12px 16px; margin: 16px 0; }
.toc ol { margin: 4px 0; }
figure { margin: 16px 0; }
figure svg { width: 100%; height: auto; display: block; }
figcaption { color: var(--muted); font-size: 14px; margin-top: 4px; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 20px 0; }
.card { border: 1px solid var(--line); border-radius: 8px; padding: 16px; }
.card h2 { border: 0; margin: 0 0 6px; padding: 0; font-size: 20px; }
.card .links { display: flex; flex-wrap: wrap; gap: 8px 16px; margin-top: 12px; font-weight: 600; }
footer { max-width: 860px; margin: 0 auto; padding: 16px; color: var(--muted); font-size: 13px; border-top: 1px solid var(--line); }

@media print {
    @page { size: A4; margin: 16mm 14mm; }
    body { font-size: 11pt; }
    .bar, .no-print, footer { display: none; }
    main { max-width: none; padding: 0; }
    h1 { font-size: 22pt; margin-top: 0; }
    h2 { font-size: 15pt; margin-top: 18pt; break-after: avoid; page-break-after: avoid; }
    h3 { break-after: avoid; page-break-after: avoid; }
    table { font-size: 10pt; }
    tr, figure, .note { break-inside: avoid; page-break-inside: avoid; }
    a { color: inherit; text-decoration: none; }
    .toc { break-inside: avoid; }
}