/* App Attribution Guide: online book identity. Cream page, oxblood accent, serif reading column, margin notes. */
:root {
  --page: #fbf7ef;
  --page-2: #f4eee2;
  --ink: #26221c;
  --ink-2: #4a4338;
  --muted: #857a68;
  --rule: #e2d8c6;
  --accent: #7b2d26;
  --accent-tint: #f3e3dd;
  --note: #fffaf0;
  --max: 1240px;
  --serif: "Source Serif 4", Georgia, serif;
  --sans: "Work Sans", system-ui, -apple-system, sans-serif;
  color-scheme: light;
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--page); color: var(--ink); font: 19px/1.7 var(--serif); -webkit-font-smoothing: antialiased; }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 3px; }
p { margin: 0; }
code { font: .85em ui-monospace, Menlo, monospace; background: var(--page-2); padding: 1px 5px; border-radius: 3px; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 28px; }
@media (max-width: 640px) { .wrap { padding: 0 16px; } body { font-size: 18px; } }
h1, h2, h3 { font-family: var(--serif); font-weight: 600; letter-spacing: -0.01em; line-height: 1.15; margin: 0; }
h1 { font-size: clamp(36px, 5vw, 60px); }
h2 { font-size: clamp(26px, 3vw, 34px); }
h3 { font-size: 22px; }
.sc { font: 600 12px var(--sans); letter-spacing: .12em; text-transform: uppercase; color: var(--muted); }

/* top bar */
.top { border-bottom: 1px solid var(--rule); background: rgba(251,247,239,.94); backdrop-filter: blur(6px); position: sticky; top: 0; z-index: 20; }
.top .wrap { display: flex; align-items: center; height: 58px; gap: 20px; }
.title-mark { font: 600 20px var(--serif); color: var(--ink); text-decoration: none; letter-spacing: -0.01em; }
.title-mark i { color: var(--accent); font-style: italic; }
.top nav { margin-left: auto; display: flex; gap: 22px; font: 500 14.5px var(--sans); }
.top nav a { color: var(--ink-2); text-decoration: none; }
.top nav a:hover { color: var(--accent); }
@media (max-width: 760px) { .top nav { display: none; } }

/* cover (home) */
.cover { padding: 80px 0 64px; border-bottom: 1px solid var(--rule); }
.cover .grid { display: grid; grid-template-columns: 1.3fr 1fr; gap: 64px; align-items: center; }
@media (max-width: 900px) { .cover .grid { grid-template-columns: 1fr; gap: 36px; } }
.cover h1 { font-size: clamp(42px, 6vw, 76px); }
.cover h1 em { color: var(--accent); }
.cover .lead { font-size: 22px; color: var(--ink-2); margin: 22px 0 30px; max-width: 560px; font-style: italic; }
.btn { display: inline-flex; gap: 10px; align-items: center; padding: 13px 20px; background: var(--accent); color: #fff; font: 600 15px var(--sans); text-decoration: none; border-radius: 3px; }
.btn:hover { background: #63231d; }
.btn.ghost { background: transparent; color: var(--ink); border: 1px solid var(--ink); }
.btn.ghost:hover { background: var(--ink); color: var(--page); }
.ctas { display: flex; gap: 12px; flex-wrap: wrap; }
.book { background: var(--accent); color: #f7ece6; aspect-ratio: 3 / 4; max-width: 340px; justify-self: center; width: 100%; padding: 36px 30px; display: flex; flex-direction: column; justify-content: space-between; box-shadow: 14px 14px 0 var(--page-2), 14px 14px 0 1px var(--rule); border-radius: 2px 8px 8px 2px; position: relative; }
.book::before { content: ""; position: absolute; left: 14px; top: 0; bottom: 0; width: 1px; background: rgba(255,255,255,.25); }
.book .bt { font: 600 34px/1.05 var(--serif); }
.book .bs { font: 500 13px var(--sans); letter-spacing: .14em; text-transform: uppercase; opacity: .8; }
.book .be { font: italic 17px var(--serif); opacity: .9; }

/* contents list */
.contents { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--ink); }
.contents li a { display: grid; grid-template-columns: 64px 1fr auto; gap: 18px; align-items: baseline; padding: 18px 0; border-bottom: 1px solid var(--rule); text-decoration: none; color: var(--ink); }
.contents li a:hover h3 { color: var(--accent); }
.contents .no { font: 600 15px var(--sans); color: var(--accent); }
.contents p { font-size: 16.5px; color: var(--muted); margin-top: 4px; }
.contents .mins { font: 500 13px var(--sans); color: var(--muted); white-space: nowrap; }
@media (max-width: 640px) { .contents li a { grid-template-columns: 44px 1fr; } .contents .mins { display: none; } }

section.block { padding: 64px 0; }
.sec-head { margin-bottom: 26px; }
.sec-head h2 { margin-top: 8px; }

/* reading layout */
.reader { display: grid; grid-template-columns: 240px minmax(0, 700px) 1fr; gap: 48px; padding: 44px 0 30px; }
@media (max-width: 1100px) { .reader { grid-template-columns: 220px minmax(0, 1fr); } .reader .margin { display: none; } }
@media (max-width: 860px) { .reader { grid-template-columns: 1fr; gap: 0; } .toc { display: none; } }
.toc { position: sticky; top: 80px; align-self: start; font: 14.5px/1.45 var(--sans); max-height: calc(100vh - 100px); overflow: auto; }
.toc .sc { display: block; margin-bottom: 12px; }
.toc ol { list-style: none; margin: 0; padding: 0; counter-reset: ch; }
.toc li a { display: grid; grid-template-columns: 26px 1fr; gap: 6px; padding: 7px 0; color: var(--ink-2); text-decoration: none; border-bottom: 1px solid var(--rule); }
.toc li a span { color: var(--muted); }
.toc li a.on { color: var(--accent); font-weight: 600; }
.toc li a.on span { color: var(--accent); }
.toc .extra { margin-top: 18px; display: grid; gap: 6px; }

.chapter-head { margin-bottom: 30px; }
.chapter-head .sc { color: var(--accent); }
.chapter-head h1 { margin-top: 10px; font-size: clamp(34px, 4.4vw, 50px); }
.chapter-head .lead { font-style: italic; font-size: 21px; color: var(--ink-2); margin-top: 14px; }
.text h2 { margin: 44px 0 14px; font-size: 29px; }
.text h3 { margin: 28px 0 8px; }
.text p { margin: 0 0 18px; color: var(--ink); }
.text p:first-of-type::first-letter { font-size: 3.2em; float: left; line-height: .85; padding: 6px 8px 0 0; color: var(--accent); font-weight: 600; }
.text ul, .text ol { padding-left: 24px; margin: 0 0 20px; }
.text li { margin: 6px 0; }
.text strong { font-weight: 650; }
.text table { width: 100%; border-collapse: collapse; margin: 6px 0 26px; font: 15.5px/1.5 var(--sans); }
.text th, .text td { padding: 10px 10px; border-bottom: 1px solid var(--rule); text-align: left; vertical-align: top; }
.text th { border-bottom: 1.5px solid var(--ink); font-weight: 600; font-size: 13px; text-transform: uppercase; letter-spacing: .06em; color: var(--ink-2); }
.text .tldr { border-top: 1.5px solid var(--ink); border-bottom: 1px solid var(--rule); padding: 16px 0; margin: 0 0 30px; font-size: 18px; }
.text .tldr p::first-letter { all: unset; }
.text .tldr p { margin: 0; }
.text .note { background: var(--note); border-left: 3px solid var(--accent); padding: 12px 16px; margin: 0 0 20px; font: 15.5px/1.6 var(--sans); color: var(--ink-2); }
.text .note b { color: var(--accent); }
.margin { font: 14px/1.55 var(--sans); color: var(--muted); padding-top: 110px; }
.margin .sc { display: block; margin-bottom: 10px; }
.margin a { display: block; padding: 4px 0; color: var(--ink-2); text-decoration: none; }
.margin a:hover { color: var(--accent); }
.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; border-top: 1.5px solid var(--ink); margin-top: 40px; padding-top: 18px; font-family: var(--sans); }
.pager a { text-decoration: none; color: var(--ink); }
.pager a .sc { display: block; }
.pager a b { font: 600 19px var(--serif); }
.pager .next { text-align: right; }

/* glossary */
.gloss { columns: 2; column-gap: 48px; }
@media (max-width: 760px) { .gloss { columns: 1; } }
.gloss div { break-inside: avoid; padding: 12px 0; border-bottom: 1px solid var(--rule); }
.gloss dt { font-weight: 600; }
.gloss dd { margin: 4px 0 0; color: var(--ink-2); font-size: 17px; }
.letters { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 20px; font: 600 14px var(--sans); }
.letters a { padding: 4px 9px; border: 1px solid var(--rule); text-decoration: none; }

/* faq */
.faq { border-top: 1.5px solid var(--ink); }
.faq details { border-bottom: 1px solid var(--rule); padding: 16px 0; }
.faq summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--sans); color: var(--accent); }
.faq details[open] summary::after { content: "−"; }
.faq details p { color: var(--ink-2); margin-top: 8px; font-size: 17.5px; }

.prose { max-width: 700px; padding: 44px 0; }
.prose h2 { margin: 30px 0 10px; font-size: 26px; }
.prose p + p { margin-top: 14px; }

footer.site { border-top: 1px solid var(--rule); padding: 40px 0 26px; margin-top: 40px; font: 14.5px var(--sans); color: var(--muted); background: var(--page-2); }
footer.site .cols { display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 24px; }
@media (max-width: 760px) { footer.site .cols { grid-template-columns: 1fr; } }
footer.site h4 { font: 600 12px var(--sans); letter-spacing: .1em; text-transform: uppercase; color: var(--ink); margin: 0 0 10px; }
footer.site ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
footer.site a { color: var(--ink-2); text-decoration: none; }
footer.site .bottom { margin-top: 28px; padding-top: 14px; border-top: 1px solid var(--rule); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 13px; }