/* Layout concept: a construction drawing set. Each page is a "sheet" with a title block,
   a drawing register lists the exams, and credit codes and sheet numbers set in mono. */
:root {
  --paper: #f5f5f1;
  --leaf: #2f6b4f;
  --leaf-soft: #e7efe8;
  --redline: #c8372d;
  --f-hand: "Caveat", "Bradley Hand", cursive;
  --sheet: #ffffff;
  --ink: #14201b;
  --muted: #56645e;
  --rule: #d3dbd7;
  --rule-strong: #14201b;
  --accent: #1d47c9;
  --accent-soft: #e6ecfb;
  --accent-ink: #ffffff;
  --good: #1c7a4c;
  --warn: #a8660a;
  --bad: #b42318;
  --grid: rgba(29, 71, 201, 0.07);

  --f-display: "Archivo", "Helvetica Neue", Arial, sans-serif;
  --f-body: "Source Serif 4", Georgia, "Times New Roman", serif;
  --f-mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

  --s-1: 0.8125rem; --s0: 1.0625rem; --s1: 1.25rem; --s2: 1.625rem; --s3: 2.25rem; --s4: clamp(2.4rem, 5.2vw, 3.9rem);
  --wrap: 72rem;
  --measure: 40rem;
  --radius: 3px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #0d1412; --sheet: #131c19; --ink: #e3eae7; --muted: #9aaba4; --rule: #2a3632; --rule-strong: #c9d4cf;
    --accent: #8fa9ff; --accent-soft: #1b2440; --accent-ink: #0d1412; --good: #5cc892; --warn: #e8b04c; --bad: #ff8a80;
    --grid: rgba(143, 169, 255, 0.06); --leaf: #7cc39d; --leaf-soft: #17261f; --redline: #ff8a7a; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #0d1412; --sheet: #131c19; --ink: #e3eae7; --muted: #9aaba4; --rule: #2a3632; --rule-strong: #c9d4cf;
  --accent: #8fa9ff; --accent-soft: #1b2440; --accent-ink: #0d1412; --good: #5cc892; --warn: #e8b04c; --bad: #ff8a80;
  --grid: rgba(143, 169, 255, 0.06); --leaf: #7cc39d; --leaf-soft: #17261f; --redline: #ff8a7a; color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font-family: var(--f-body); font-size: var(--s0); line-height: 1.6;
  font-optical-sizing: auto;
}
img { max-width: 100%; }
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
h1, h2, h3 { font-family: var(--f-display); font-stretch: 112%; line-height: 1.12; text-wrap: balance; margin: 0; letter-spacing: -0.01em; }
h1 { font-size: var(--s4); font-weight: 800; }
h2 { font-size: var(--s3); font-weight: 750; }
h3 { font-size: var(--s1); font-weight: 700; }
p { margin: 0; }
.mono, .label { font-family: var(--f-mono); }
.label { font-size: var(--s-1); letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); }
.wrap { max-width: var(--wrap); margin-inline: auto; padding-inline: 20px; }
.prose { max-width: var(--measure); display: grid; gap: 1.1rem; }
.prose h2 { font-size: var(--s2); margin-top: 1.4rem; }
.prose h3 { margin-top: 0.6rem; }
.prose ul, .prose ol { margin: 0; padding-left: 1.2rem; display: grid; gap: 0.4rem; }
.lede { font-size: var(--s1); color: var(--muted); max-width: 38rem; }
.stack { display: grid; gap: 1.25rem; }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 16px; top: 16px; background: var(--sheet); padding: 8px 12px; z-index: 10; }

/* Header: title-block strip */
.site-head { border-bottom: 1px solid var(--rule-strong); background: var(--sheet); position: sticky; top: env(safe-area-inset-top, 0px); z-index: 5; }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 1rem; flex-wrap: wrap; padding-block: 0.85rem; }
.mark { font-family: var(--f-display); font-stretch: 125%; font-weight: 800; font-size: 1.05rem; letter-spacing: 0.04em; text-transform: uppercase; color: var(--ink); text-decoration: none; display: flex; align-items: baseline; gap: 0.6rem; }
.mark small { font-family: var(--f-mono); font-weight: 400; font-size: 0.72rem; letter-spacing: 0.06em; color: var(--muted); font-stretch: 100%; }
.nav { display: flex; gap: 0.25rem 1.25rem; flex-wrap: wrap; font-family: var(--f-display); font-size: 0.95rem; font-weight: 600; }
.nav a { color: var(--ink); text-decoration: none; padding-block: 0.2rem; border-bottom: 2px solid transparent; }
.nav a:hover, .nav a[aria-current="page"] { border-bottom-color: var(--accent); }

/* Buttons */
.btn { display: inline-flex; align-items: center; gap: 0.5rem; font-family: var(--f-display); font-weight: 700; font-size: 1rem; padding: 0.75rem 1.15rem; border-radius: var(--radius); border: 1.5px solid var(--accent); background: var(--accent); color: var(--accent-ink); text-decoration: none; cursor: pointer; }
.btn:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; color: var(--accent); }
.btn.small { padding: 0.5rem 0.85rem; font-size: 0.9rem; }
.btn-row { display: flex; flex-wrap: wrap; gap: 0.75rem; }

/* Hero with drawing grid */
.hero { border-bottom: 1px solid var(--rule); background-color: var(--sheet);
  background-image: linear-gradient(var(--grid) 1px, transparent 1px), linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 24px 24px; }
.hero .wrap { padding-block: clamp(2.5rem, 7vw, 5rem); display: grid; gap: 1.5rem; }
.hero h1 { max-width: 16ch; }
.hero .stamp { justify-self: start; font-family: var(--f-mono); font-size: var(--s-1); border: 1.5px solid var(--accent); color: var(--accent); padding: 0.3rem 0.6rem; letter-spacing: 0.06em; text-transform: uppercase; }

section.band { padding-block: clamp(2.5rem, 6vw, 4rem); }
section.band + section.band { border-top: 1px solid var(--rule); }
.section-head { display: grid; gap: 0.5rem; margin-bottom: 1.75rem; max-width: 44rem; }

/* Drawing register (exam table) */
.register-wrap { overflow-x: auto; border: 1px solid var(--rule-strong); background: var(--sheet); }
table.register { width: 100%; border-collapse: collapse; font-size: 0.98rem; min-width: 640px; }
.register th { font-family: var(--f-mono); font-weight: 500; font-size: var(--s-1); text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); text-align: left; padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--rule-strong); }
.register td { padding: 0.9rem; border-bottom: 1px solid var(--rule); vertical-align: top; }
.register tr:last-child td { border-bottom: 0; }
.register td.sheetno { font-family: var(--f-mono); color: var(--accent); white-space: nowrap; }
.register td.name a { font-family: var(--f-display); font-weight: 700; color: var(--ink); text-decoration: none; }
.register td.name a:hover { color: var(--accent); }
.register td.num { font-variant-numeric: tabular-nums; white-space: nowrap; }

/* Pills */
.pill { display: inline-block; font-family: var(--f-mono); font-size: 0.72rem; letter-spacing: 0.05em; text-transform: uppercase; padding: 0.15rem 0.45rem; border-radius: 2px; border: 1px solid currentColor; white-space: nowrap; }
.pill.live { color: var(--good); }
.pill.beta { color: var(--warn); }

/* Cards (used sparingly: course offers) */
.offers { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 19rem), 1fr)); gap: 1rem; }
.offer { background: var(--sheet); border: 1px solid var(--rule); border-top: 3px solid var(--rule-strong); padding: 1.25rem; display: grid; gap: 0.75rem; align-content: start; min-width: 0; }
.offer.primary { border-top-color: var(--accent); }
.offer .facts { font-family: var(--f-mono); font-size: 0.85rem; color: var(--muted); }
.offer .btn { justify-self: start; }

/* Two-column split */
.split { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr); gap: clamp(1.5rem, 4vw, 3rem); align-items: start; }
@media (max-width: 800px) { .split { grid-template-columns: 1fr; } }

/* Blueprint weights */
.weights { display: grid; gap: 0.55rem; background: var(--sheet); border: 1px solid var(--rule); padding: 1.1rem 1.25rem; }
.weight { display: grid; grid-template-columns: minmax(0, 11rem) minmax(0, 1fr) 2.5rem; gap: 0.75rem; align-items: center; font-size: 0.93rem; }
.weight .bar { height: 10px; background: var(--accent-soft); position: relative; }
.weight .bar span { position: absolute; inset: 0 auto 0 0; background: var(--accent); }
.weight .n { font-family: var(--f-mono); font-variant-numeric: tabular-nums; text-align: right; }
.weights .caption { font-size: var(--s-1); color: var(--muted); font-family: var(--f-mono); }

/* Spec list (exam facts) */
.spec { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 10rem), 1fr)); border: 1px solid var(--rule-strong); background: var(--sheet); }
.spec div { padding: 0.9rem 1rem; border-right: 1px solid var(--rule); border-bottom: 1px solid var(--rule); display: grid; gap: 0.2rem; }
.spec dt { font-family: var(--f-mono); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); }
.spec dd { margin: 0; font-family: var(--f-display); font-weight: 700; font-size: 1.15rem; }

.note { border-left: 3px solid var(--warn); background: var(--sheet); padding: 0.85rem 1rem; font-size: 0.95rem; }

/* Forms */
.form { display: grid; gap: 1rem; max-width: 36rem; }
.field { display: grid; gap: 0.35rem; }
.field label { font-family: var(--f-display); font-weight: 600; font-size: 0.95rem; }
.field input, .field select, .field textarea { font: inherit; font-size: 1rem; padding: 0.65rem 0.75rem; border: 1px solid var(--rule-strong); border-radius: var(--radius); background: var(--sheet); color: var(--ink); width: 100%; }
.form-status { font-family: var(--f-mono); font-size: 0.85rem; color: var(--good); }

/* Article */
.article-meta { font-family: var(--f-mono); font-size: var(--s-1); color: var(--muted); }
.table-wrap { overflow-x: auto; }
table.plain { border-collapse: collapse; width: 100%; font-size: 0.95rem; }
table.plain th, table.plain td { text-align: left; padding: 0.55rem 0.7rem; border-bottom: 1px solid var(--rule); vertical-align: top; }
table.plain th { font-family: var(--f-mono); font-weight: 500; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); border-bottom-color: var(--rule-strong); }
.post-list { display: grid; gap: 0; border-top: 1px solid var(--rule-strong); }
.post-list a { display: grid; gap: 0.3rem; padding: 1.1rem 0; border-bottom: 1px solid var(--rule); text-decoration: none; color: var(--ink); }
.post-list a strong { font-family: var(--f-display); font-size: var(--s1); }
.post-list a:hover strong { color: var(--accent); }
.post-list .soon { color: var(--muted); }

/* Footer title block */
.site-foot { border-top: 1px solid var(--rule-strong); background: var(--sheet); margin-top: 0; }
.titleblock { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 13rem), 1fr)); border-left: 1px solid var(--rule); }
.titleblock > div { padding: 1rem; border-right: 1px solid var(--rule); border-bottom: 1px solid var(--rule); display: grid; gap: 0.3rem; align-content: start; font-size: 0.92rem; }
.titleblock a { color: var(--ink); }
.disclaimer { font-size: 0.82rem; color: var(--muted); padding-block: 1rem 1.5rem; max-width: 60rem; }

/* Quiz */
.quiz { background: var(--sheet); border: 1px solid var(--rule-strong); padding: clamp(1.1rem, 3vw, 2rem); display: grid; gap: 1.25rem; }
.quiz-top { display: flex; justify-content: space-between; gap: 1rem; flex-wrap: wrap; align-items: center; }
.progress { height: 4px; background: var(--rule); }
.progress span { display: block; height: 100%; background: var(--accent); transition: width 0.25s ease; }
.q-stem { font-family: var(--f-body); font-size: var(--s1); line-height: 1.45; font-weight: 600; }
.options { display: grid; gap: 0.6rem; }
.option { text-align: left; font: inherit; font-size: 1rem; line-height: 1.45; padding: 0.85rem 1rem; border: 1px solid var(--rule); border-radius: var(--radius); background: var(--paper); color: var(--ink); cursor: pointer; display: grid; grid-template-columns: 1.6rem minmax(0, 1fr); gap: 0.5rem; }
.option:hover { border-color: var(--accent); }
.option[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); box-shadow: inset 3px 0 0 var(--accent); }
.option .key { font-family: var(--f-mono); color: var(--muted); }
.option.correct { border-color: var(--good); box-shadow: inset 3px 0 0 var(--good); }
.option.wrong { border-color: var(--bad); box-shadow: inset 3px 0 0 var(--bad); }
.exam-picker { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 13rem), 1fr)); gap: 0.6rem; }
.exam-picker button { font: inherit; text-align: left; padding: 0.9rem 1rem; border: 1px solid var(--rule); background: var(--paper); color: var(--ink); border-radius: var(--radius); cursor: pointer; display: grid; gap: 0.25rem; }
.exam-picker button:hover:not(:disabled) { border-color: var(--accent); }
.exam-picker button:disabled { cursor: default; opacity: 0.6; }
.exam-picker strong { font-family: var(--f-display); }
.score { display: flex; align-items: baseline; gap: 1rem; flex-wrap: wrap; }
.score .big { font-family: var(--f-display); font-stretch: 125%; font-weight: 800; font-size: clamp(3rem, 9vw, 4.5rem); line-height: 1; font-variant-numeric: tabular-nums; }
.domain-row { display: grid; grid-template-columns: minmax(0, 12rem) minmax(0, 1fr) 3.5rem; gap: 0.75rem; align-items: center; font-size: 0.93rem; }
.domain-row .bar { height: 10px; background: var(--rule); position: relative; }
.domain-row .bar span { position: absolute; inset: 0 auto 0 0; }
.domain-row .n { font-family: var(--f-mono); text-align: right; font-variant-numeric: tabular-nums; }
.review-item { border-top: 1px solid var(--rule); padding-top: 1rem; display: grid; gap: 0.6rem; }
.explain { font-size: 0.95rem; color: var(--muted); }
@media (max-width: 560px) { .weight, .domain-row { grid-template-columns: minmax(0, 1fr) 2.5rem; } .weight .bar, .domain-row .bar { grid-column: 1 / -1; grid-row: 2; } }
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }
@media (max-width: 700px) { .site-head { position: static; } }

/* v2 additions */
.form-status.bad { color: var(--bad); }
.verdict { font-family: var(--f-display); font-weight: 700; }
.verdict.ok { color: var(--good); }
.verdict.no { color: var(--bad); }
.option[aria-disabled="true"] { cursor: default; }
.form.inline { grid-template-columns: minmax(0, 1fr) auto; align-items: end; max-width: 34rem; }
.form.inline .form-status { grid-column: 1 / -1; }
@media (max-width: 520px) { .form.inline { grid-template-columns: 1fr; } }
.domain-row.head .bar { height: auto; background: none; }
.gate { border-top: 1px solid var(--rule-strong); padding-top: 1.25rem; }
.hero-split { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); gap: clamp(1.5rem, 4vw, 3rem); align-items: start; }
@media (max-width: 900px) { .hero-split { grid-template-columns: 1fr; } }
.sample { background: var(--sheet); border: 1px solid var(--rule-strong); box-shadow: 6px 6px 0 var(--accent-soft); padding: clamp(1rem, 2.5vw, 1.5rem); display: grid; gap: 1rem; min-width: 0; }
.sample .q-stem { font-size: 1.05rem; }
.sample .option { font-size: 0.95rem; padding: 0.7rem 0.85rem; }
.faq { border-top: 1px solid var(--rule-strong); max-width: 48rem; }
.faq details { border-bottom: 1px solid var(--rule); padding-block: 0.9rem; }
.faq summary { cursor: pointer; font-family: var(--f-display); font-weight: 700; font-size: 1.05rem; list-style: none; display: flex; justify-content: space-between; gap: 1rem; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--f-mono); color: var(--accent); }
.faq details[open] summary::after { content: "–"; }
.faq details p { margin-top: 0.6rem; max-width: var(--measure); }
.alert-box { background: var(--sheet); border: 1px solid var(--rule); padding: 1.25rem; display: grid; gap: 0.75rem; }
.proof { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 14rem), 1fr)); gap: 0; border: 1px solid var(--rule-strong); background: var(--sheet); }
.proof > div { padding: 1rem 1.1rem; border-right: 1px solid var(--rule); display: grid; gap: 0.3rem; }
.proof strong { font-family: var(--f-display); font-stretch: 112%; font-size: var(--s2); line-height: 1.1; }
.portrait { width: 100%; max-width: 20rem; aspect-ratio: 4 / 5; background: var(--accent-soft); border: 1px solid var(--rule); display: grid; place-items: center; color: var(--muted); font-family: var(--f-mono); font-size: 0.8rem; text-align: center; padding: 1rem; }
table.plain td.num { font-variant-numeric: tabular-nums; white-space: nowrap; }

/* v3: warmth and personality */
.band.tight { padding-block: 1.5rem; }
.hero h1 { font-size: clamp(2.2rem, 4.4vw, 3.4rem); max-width: 17ch; }
.byline { display: flex; align-items: center; gap: 0.8rem; text-decoration: none; color: var(--ink); margin-top: 0.5rem; }
.byline img { width: 56px; height: 56px; border-radius: 50%; object-fit: cover; border: 2px solid var(--sheet); box-shadow: 0 0 0 1px var(--rule-strong); }
.byline > span { display: grid; gap: 0.1rem; }
.byline strong { font-family: var(--f-display); }
.byline .mono { font-size: 0.75rem; color: var(--muted); }
.sample-wrap { position: relative; display: grid; padding-top: 1.6rem; min-width: 0; }
.redline { position: absolute; top: -0.2rem; right: 0.5rem; font-family: var(--f-hand); font-size: 1.55rem; color: var(--redline); transform: rotate(-3deg); line-height: 1; pointer-events: none; }
.sample { border-color: var(--rule-strong); box-shadow: 8px 8px 0 var(--leaf-soft); }
.note-band { background: var(--leaf-soft); }
section.band.note-band + section.band, section.band + section.band.note-band { border-top: 0; }
.letter { display: grid; grid-template-columns: auto minmax(0, 1fr); gap: clamp(1.5rem, 5vw, 3.5rem); align-items: start; max-width: 60rem; }
.letter p { max-width: 38rem; }
.portrait-lg { width: 220px; height: 220px; border-radius: 50%; object-fit: cover; border: 6px solid var(--sheet); box-shadow: 0 0 0 1px var(--rule-strong); }
@media (max-width: 700px) { .letter { grid-template-columns: 1fr; } .portrait-lg { width: 160px; height: 160px; } }
.signature { font-family: var(--f-hand); font-size: 2.4rem; color: var(--leaf); line-height: 1; transform: rotate(-4deg); transform-origin: left; }
.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 16rem), 1fr)); gap: 0; border-top: 1px solid var(--rule-strong); }
.steps li { padding: 1.25rem 1.25rem 1.25rem 0; display: grid; gap: 0.5rem; align-content: start; }
.steps li + li { padding-left: 1.25rem; border-left: 1px solid var(--rule); }
@media (max-width: 760px) { .steps li + li { padding-left: 0; border-left: 0; border-top: 1px solid var(--rule); } }
.step-n { font-family: var(--f-display); font-stretch: 125%; font-weight: 800; font-size: 2.2rem; color: var(--leaf); line-height: 1; }
.exam-cards { display: none; gap: 0.6rem; }
.exam-card { display: grid; gap: 0.25rem; padding: 1rem; background: var(--sheet); border: 1px solid var(--rule); border-left: 3px solid var(--accent); text-decoration: none; color: var(--ink); }
.exam-card strong { font-family: var(--f-display); font-size: 1.1rem; }
.exam-card .sheetno { font-family: var(--f-mono); font-size: 0.75rem; color: var(--accent); }
.exam-card .mono { font-size: 0.8rem; color: var(--muted); }
@media (max-width: 700px) { .exam-cards { display: grid; } .register-wrap { display: none; } }
.dark-band { background: var(--ink); color: var(--paper); }
.dark-band .label { color: var(--paper); opacity: 0.75; }
.dark-band .btn { background: var(--paper); color: var(--ink); border-color: var(--paper); }
.offer { padding: 0; gap: 0; border-top-width: 1px; overflow: hidden; }
.offer .cover { display: grid; grid-template-columns: 1fr auto; align-items: end; gap: 0.25rem 1rem; padding: 1rem 1.25rem; background: var(--accent); color: var(--accent-ink);
  background-image: linear-gradient(rgba(255,255,255,.09) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.09) 1px, transparent 1px); background-size: 16px 16px; }
.offer:not(.primary) .cover { background-color: var(--leaf); }
.offer .cover .mono { font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; opacity: 0.85; }
.offer .cover strong { grid-column: 1 / -1; font-family: var(--f-display); font-stretch: 125%; font-weight: 800; font-size: 2.4rem; line-height: 1; order: -1; }
.offer .offer-body { padding: 1.25rem; display: grid; gap: 0.7rem; align-content: start; }
.offer .offer-body .btn { justify-self: start; }
.foot-who { display: flex; align-items: center; gap: 0.5rem; }
.foot-who img { width: 32px; height: 32px; border-radius: 50%; object-fit: cover; }
.pill.live { color: var(--leaf); }

/* v3.1 photo */
.photo-frame { margin: 0; width: 260px; max-width: 100%; background: var(--sheet); padding: 8px 8px 0; border: 1px solid var(--rule-strong); box-shadow: 8px 8px 0 var(--accent-soft); transform: rotate(-1.5deg); }
.photo-frame img { display: block; width: 100%; height: auto; aspect-ratio: 4 / 5; object-fit: cover; }
.photo-frame figcaption { font-family: var(--f-hand); font-size: 1.3rem; color: var(--muted); text-align: center; padding: 0.35rem 0 0.45rem; }
@media (max-width: 700px) { .photo-frame { width: 220px; } }