/* SEO interview practice: shared stylesheet for the home page, both practice formats and 404.
   Layout: documents rail | one question column | context column. Below 1180px the context column
   drops under the card; below 880px the rail becomes a drawer and question navigation moves to
   a bar fixed to the bottom of the screen. */

@font-face { font-family: Manrope; src: url('fonts/Manrope.woff2') format('woff2'); font-weight: 200 800; font-style: normal; font-display: swap; }
@font-face { font-family: 'Source Sans 3'; src: url('fonts/SourceSans3.woff2') format('woff2'); font-weight: 200 900; font-style: normal; font-display: swap; }

:root {
  --paper: #f5f3ed; --surface: #ffffff; --raised: #ffffff; --sunken: #ecefe7;
  --ink: #152d3a; --muted: #536c73; --faint: #6f8589; --line: #d7e2da; --line-strong: #bccdc4;
  --teal: #007d79; --teal-strong: #00635f; --on-teal: #ffffff; --mint: #e2eee7;
  --copper: #c57535; --copper-text: #93501d; --copper-soft: #f6e6d4; --highlight: #fff0ca;
  --right: #16704e; --right-soft: #dff0e5; --wrong: #b0462a; --wrong-soft: #fae8df;
  --rail: #152d3a; --rail-2: #21414d; --rail-line: #2f4c57; --rail-fg: #c9dadb; --rail-dim: #92adb0; --rail-hi: #8ed9c9;
  --shadow: 0 1px 2px rgb(21 45 58 / 6%), 0 8px 24px rgb(21 45 58 / 6%);
  --font-display: Manrope, "Trebuchet MS", system-ui, sans-serif;
  --font-body: "Source Sans 3", "Segoe UI", system-ui, sans-serif;
  --font-mono: ui-monospace, "Cascadia Mono", "SFMono-Regular", Consolas, Menlo, monospace;
  --font-quote: Georgia, "Iowan Old Style", "Times New Roman", serif;
  --t-12: .75rem; --t-13: .8125rem; --t-14: .875rem; --t-16: 1rem; --t-18: 1.125rem; --t-22: 1.375rem; --t-28: 1.75rem; --t-36: 2.25rem; --t-48: 3rem;
  --r-sm: 6px; --r-md: 10px; --r-lg: 16px;
  --rail-w: 280px; --bar-h: 66px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #0e1c23; --surface: #14262f; --raised: #26495a; --sunken: #102028; --ink: #e4edeb; --muted: #a3b8ba; --faint: #869ea1;
    --line: #26404a; --line-strong: #345360; --teal: #4cc0b4; --teal-strong: #6fd1c6; --on-teal: #06201e; --mint: #163737;
    --copper: #e0995c; --copper-text: #eeb07a; --copper-soft: #3a2a1c; --highlight: #4a3f1c;
    --right: #6bcf9f; --right-soft: #15362a; --wrong: #f08f6c; --wrong-soft: #3b231d;
    --rail: #0a161c; --rail-2: #16303a; --rail-line: #1f3842; --rail-fg: #c9dadb; --rail-dim: #8aa5a8; --rail-hi: #8ed9c9;
    --shadow: 0 1px 2px rgb(0 0 0 / 30%), 0 8px 24px rgb(0 0 0 / 25%);
    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: 400 var(--t-16)/1.6 var(--font-body); }
h1, h2, h3, h4 { font-family: var(--font-display); line-height: 1.2; letter-spacing: -.01em; text-wrap: balance; margin: 0; }
p { margin: 0; }
a { color: var(--teal); text-underline-offset: 3px; overflow-wrap: anywhere; }
button, input, select { font: inherit; color: inherit; }
button { cursor: pointer; }
button:disabled { cursor: default; }
:focus-visible { outline: 3px solid var(--copper); outline-offset: 2px; border-radius: 4px; }
[hidden] { display: none !important; }
.mono { font-family: var(--font-mono); font-size: .9em; }
.label { font-size: var(--t-12); font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.muted { color: var(--muted); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
kbd { font-family: var(--font-mono); font-size: 11px; line-height: 1; padding: 3px 5px; min-width: 20px; text-align: center; border: 1px solid var(--line-strong); border-bottom-width: 2px; border-radius: 4px; color: var(--muted); background: var(--surface); display: inline-block; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding: 0 18px;
  border-radius: var(--r-md); border: 1px solid var(--line-strong); background: var(--surface); color: var(--ink);
  font-weight: 600; font-size: var(--t-14); text-decoration: none; white-space: nowrap; transition: background-color .15s, border-color .15s, color .15s;
}
.btn:hover { border-color: var(--teal); }
.btn-primary { background: var(--teal); border-color: var(--teal); color: var(--on-teal); }
.btn-primary:hover { background: var(--teal-strong); border-color: var(--teal-strong); color: var(--on-teal); }
.btn-ghost { background: transparent; border-color: transparent; color: var(--teal); padding: 0 10px; }
.btn-ghost:hover { background: var(--mint); border-color: transparent; }
.btn-sm { min-height: 34px; padding: 0 12px; font-size: var(--t-13); }
.btn:disabled { opacity: .45; }
.btn svg { width: 18px; height: 18px; flex-shrink: 0; }
.icon-btn { width: 40px; height: 40px; border: 0; border-radius: var(--r-md); background: transparent; display: inline-grid; place-items: center; color: var(--muted); padding: 0; flex-shrink: 0; }
.icon-btn:hover { background: var(--sunken); color: var(--ink); }
.icon-btn svg { width: 20px; height: 20px; }

.seg { display: inline-flex; padding: 3px; border-radius: var(--r-md); background: var(--sunken); border: 1px solid var(--line); }
.seg button { border: 0; background: transparent; color: var(--muted); font-weight: 600; font-size: var(--t-14); min-height: 36px; padding: 0 14px; border-radius: 7px; white-space: nowrap; display: inline-flex; align-items: center; justify-content: center; gap: 7px; }
.seg button svg { width: 16px; height: 16px; }
.seg button[aria-checked="true"] { background: var(--raised); color: var(--ink); box-shadow: 0 1px 2px rgb(21 45 58 / 12%); }

/* ---------- App shell ---------- */
.app { display: grid; grid-template-columns: var(--rail-w) minmax(0, 1fr); min-height: 100vh; }
.rail { position: sticky; top: 0; height: 100vh; overflow-y: auto; overscroll-behavior: contain; background: var(--rail); color: var(--rail-fg); padding: 20px 14px 28px; display: flex; flex-direction: column; gap: 18px; font-size: var(--t-14); }
.brand { display: flex; align-items: center; gap: 12px; padding: 2px 6px; color: #fff; text-decoration: none; }
.brand svg { width: 34px; height: 34px; flex-shrink: 0; }
.brand b { font-family: var(--font-display); font-size: var(--t-16); font-weight: 700; display: block; line-height: 1.25; }
.brand small { display: block; color: var(--rail-dim); font-size: var(--t-12); line-height: 1.4; }
.rail-views { display: none; }
.rail-find { position: relative; display: block; }
.rail-find svg { position: absolute; left: 11px; top: 50%; transform: translateY(-50%); width: 16px; height: 16px; color: var(--rail-dim); }
.rail-find input { width: 100%; height: 40px; border-radius: var(--r-md); border: 1px solid var(--rail-line); background: var(--rail-2); color: #fff; padding: 0 12px 0 34px; font-size: var(--t-14); }
.rail-find input::placeholder { color: var(--rail-dim); }
.rail-all { display: flex; align-items: center; justify-content: space-between; width: 100%; min-height: 40px; padding: 0 10px; border: 0; border-radius: var(--r-sm); background: transparent; color: var(--rail-fg); font-weight: 600; text-align: left; }
.rail-all:hover { background: var(--rail-2); }
.rail-all[aria-pressed="true"] { background: var(--rail-2); color: #fff; }
.rail-all span { font-variant-numeric: tabular-nums; color: var(--rail-dim); font-weight: 400; font-size: var(--t-13); }
.area { display: flex; flex-direction: column; gap: 2px; }
.area-name { font-size: var(--t-12); font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--rail-dim); padding: 10px 10px 6px; }
.grp-head { width: 100%; display: grid; grid-template-columns: 14px minmax(0, 1fr) auto; align-items: center; gap: 4px 8px; padding: 8px 10px; border: 0; border-radius: var(--r-sm); background: transparent; color: var(--rail-fg); text-align: left; font-size: var(--t-14); }
.grp-head:hover { background: var(--rail-2); }
.grp-head .chev { width: 14px; height: 14px; transition: transform .15s; color: var(--rail-dim); }
.grp-head[aria-expanded="true"] .chev { transform: rotate(90deg); }
.grp-head .n { font-variant-numeric: tabular-nums; font-size: var(--t-12); color: var(--rail-dim); }
.grp-bar { grid-column: 2 / 4; height: 3px; border-radius: 3px; background: var(--rail-line); overflow: hidden; }
.grp-bar i { display: block; height: 100%; background: var(--rail-hi); }
.grp-docs { list-style: none; margin: 2px 0 8px; padding: 0 0 0 22px; display: flex; flex-direction: column; gap: 1px; }
.doc { position: relative; width: 100%; display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 10px; align-items: baseline; padding: 6px 8px; border: 0; border-radius: var(--r-sm); background: transparent; color: var(--rail-fg); text-align: left; font-size: var(--t-13); line-height: 1.4; }
.doc:hover { background: var(--rail-2); color: #fff; }
.doc[aria-pressed="true"] { background: var(--rail-2); color: #fff; font-weight: 600; }
.doc .n { font-variant-numeric: tabular-nums; color: var(--rail-dim); font-size: var(--t-12); font-weight: 400; }
.doc .n.done { color: var(--rail-hi); }
.doc.is-here::before { content: ""; position: absolute; left: -12px; top: 13px; width: 6px; height: 6px; border-radius: 50%; background: var(--rail-hi); }
.doc.all-in-group { color: var(--rail-dim); font-style: normal; }
.rail-empty { padding: 8px 10px; color: var(--rail-dim); font-size: var(--t-13); }
.rail-foot { margin-top: auto; padding: 14px 10px 0; border-top: 1px solid var(--rail-line); font-size: var(--t-12); color: var(--rail-dim); line-height: 1.5; }
.scrim { display: none; }

.workspace { min-width: 0; display: flex; flex-direction: column; }
.topbar { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 20; height: 60px; display: flex; align-items: center; gap: 16px; padding: 0 32px; background: var(--paper); border-bottom: 1px solid var(--line); }
.topbar .menu-btn, .top-brand, .top-progress { display: none; }
.views { display: flex; gap: 4px; height: 100%; }
.views button { border: 0; background: transparent; color: var(--muted); font-weight: 600; font-size: var(--t-14); padding: 0 12px; height: 100%; border-bottom: 2px solid transparent; margin-bottom: -1px; }
.views button:hover { color: var(--ink); }
.views button[aria-selected="true"] { color: var(--ink); border-bottom-color: var(--teal); }
.top-actions { margin-left: auto; display: flex; align-items: center; gap: 4px; position: relative; }
.popover { position: absolute; right: 0; top: calc(100% + 8px); width: 360px; z-index: 30; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--shadow); padding: 8px; }
.dl-list { list-style: none; margin: 0; padding: 0; }
.dl-list li { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 2px 12px; padding: 10px; align-items: center; }
.dl-list li + li { border-top: 1px solid var(--line); }
.dl-list b { font-weight: 600; font-size: var(--t-14); }
.dl-list small { grid-column: 1; color: var(--muted); font-size: var(--t-12); }
.dl-list .files { grid-row: 1 / 3; grid-column: 2; display: flex; gap: 6px; }
.file-link { display: inline-flex; gap: 5px; align-items: center; font-size: var(--t-12); font-weight: 700; text-decoration: none; padding: 5px 8px; border: 1px solid var(--line-strong); border-radius: var(--r-sm); color: var(--ink); white-space: nowrap; }
.file-link span { color: var(--muted); font-weight: 400; }
.file-link:hover { border-color: var(--teal); color: var(--teal); }

.content { display: grid; grid-template-columns: minmax(0, 760px) 300px; justify-content: center; align-items: start; gap: 28px; padding-block: 24px 40px; padding-inline: 32px; }
.content.single { grid-template-columns: minmax(0, 900px); }
.stage { min-width: 0; display: flex; flex-direction: column; gap: 14px; }
.notice { padding: 12px 16px; border-radius: var(--r-md); background: var(--copper-soft); color: var(--ink); font-size: var(--t-14); }
.loading { padding: 32px; border: 1px solid var(--line); border-radius: var(--r-lg); background: var(--surface); color: var(--muted); }

.session { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.search { position: relative; flex: 1 1 260px; min-width: 0; display: flex; align-items: center; height: 44px; border: 1px solid var(--line-strong); border-radius: var(--r-md); background: var(--surface); }
.search:focus-within { border-color: var(--teal); }
.search > svg { width: 18px; height: 18px; margin: 0 8px 0 12px; color: var(--faint); flex-shrink: 0; }
.search input { flex: 1; min-width: 0; height: 100%; border: 0; background: transparent; font-size: var(--t-14); outline: none; }
.search input::-webkit-search-cancel-button { display: none; }
.search .icon-btn { width: 36px; height: 36px; margin-right: 3px; }
.filter-btn .badge { background: var(--teal); color: var(--on-teal); border-radius: 999px; font-size: var(--t-12); min-width: 20px; height: 20px; display: inline-grid; place-items: center; padding: 0 6px; font-variant-numeric: tabular-nums; }
.scope { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: var(--t-13); color: var(--muted); min-height: 32px; }
.scope .count { font-variant-numeric: tabular-nums; }
.scope .sep { width: 1px; height: 16px; background: var(--line-strong); }
.chip { display: inline-flex; align-items: center; gap: 4px; min-height: 30px; padding: 2px 4px 2px 10px; border-radius: 999px; background: var(--mint); color: var(--ink); font-size: var(--t-13); font-weight: 600; max-width: 100%; }
.chip > span { overflow-wrap: anywhere; }
.chip button { width: 24px; height: 24px; flex-shrink: 0; border: 0; border-radius: 50%; background: transparent; color: var(--muted); display: grid; place-items: center; padding: 0; }
.chip button:hover { background: var(--surface); color: var(--ink); }
.chip button svg { width: 14px; height: 14px; }
.scope .btn-ghost { min-height: 30px; font-size: var(--t-13); }

/* ---------- Question card ---------- */
.qcard { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--shadow); padding: 28px 32px 0; display: flex; flex-direction: column; gap: 20px; scroll-margin-top: 80px; }
.q-meta { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; font-size: var(--t-13); color: var(--muted); }
.q-where { min-width: 0; display: flex; flex-direction: column; gap: 2px; }
.q-pos { font-variant-numeric: tabular-nums; }
.q-pos b { color: var(--ink); }
.q-doc { color: var(--muted); text-decoration: none; font-weight: 600; text-align: left; border: 0; background: none; padding: 0; font-size: inherit; }
.q-doc:hover { color: var(--teal); text-decoration: underline; }
.q-tags { display: flex; gap: 8px; align-items: center; flex-shrink: 0; }
.tag { font-size: var(--t-12); font-weight: 700; padding: 3px 8px; border-radius: var(--r-sm); border: 1px solid var(--line-strong); color: var(--ink); white-space: nowrap; }
.q-key { color: var(--faint); font-size: var(--t-12); }
.q-tags .icon-btn { width: 32px; height: 32px; }
.q-tags .icon-btn svg { width: 17px; height: 17px; }
.copy-status { font-size: var(--t-12); color: var(--right); }
.q-text { font-size: var(--t-28); font-weight: 700; letter-spacing: -.015em; line-height: 1.3; }
.options { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 10px; }
.opt { width: 100%; display: grid; grid-template-columns: 32px minmax(0, 1fr) auto; gap: 14px; align-items: start; text-align: left; padding: 14px 16px; border-radius: var(--r-md); border: 1px solid var(--line-strong); background: var(--surface); font-size: var(--t-16); line-height: 1.5; color: var(--ink); transition: border-color .15s, background-color .15s; }
.opt:not(:disabled):hover { border-color: var(--teal); background: var(--mint); }
.opt-key { width: 32px; height: 32px; border-radius: var(--r-sm); display: grid; place-items: center; border: 1px solid var(--line-strong); font-family: var(--font-display); font-weight: 700; font-size: var(--t-14); color: var(--muted); margin-top: -4px; }
.opt-text { min-width: 0; overflow-wrap: anywhere; }
.opt-state { font-size: var(--t-13); font-weight: 700; white-space: nowrap; display: inline-flex; gap: 6px; align-items: center; padding-top: 1px; }
.opt-state svg { width: 16px; height: 16px; }
.opt:disabled { color: var(--muted); }
.opt.is-right { border-color: var(--right); background: var(--right-soft); color: var(--ink); }
.opt.is-right .opt-key { background: var(--right); border-color: var(--right); color: var(--surface); }
.opt.is-right .opt-state { color: var(--right); }
.opt.is-wrong { border-color: var(--wrong); background: var(--wrong-soft); color: var(--ink); }
.opt.is-wrong .opt-key { background: var(--wrong); border-color: var(--wrong); color: var(--surface); }
.opt.is-wrong .opt-state { color: var(--wrong); }
.peek { align-self: flex-start; margin-top: -8px; }
.aloud { display: flex; flex-direction: column; gap: 18px; }
.aloud-prompt { font-size: var(--t-16); color: var(--muted); max-width: 60ch; }
.timer { align-self: flex-start; display: inline-flex; align-items: center; gap: 12px; padding: 6px 8px 6px 6px; border: 1px solid var(--line); border-radius: 999px; }
.timer svg { width: 40px; height: 40px; transform: rotate(-90deg); }
.timer .track { stroke: var(--line); }
.timer .arc { stroke: var(--teal); transition: stroke-dashoffset 1s linear; }
.timer.is-low .arc { stroke: var(--copper); }
.timer output { font-family: var(--font-display); font-weight: 700; font-size: var(--t-18); font-variant-numeric: tabular-nums; min-width: 3.2ch; }
.timer .btn { min-height: 34px; padding: 0 12px; border-radius: 999px; }
.verdict { display: grid; grid-template-columns: 20px minmax(0, 1fr) auto; align-items: center; gap: 8px 12px; padding: 12px 16px; border-radius: var(--r-md); font-size: var(--t-14); }
.verdict svg { width: 20px; height: 20px; }
.verdict.ok { background: var(--right-soft); } .verdict.ok svg { color: var(--right); }
.verdict.no { background: var(--wrong-soft); } .verdict.no svg { color: var(--wrong); }
.verdict.peeked { background: var(--sunken); } .verdict.peeked svg { color: var(--muted); }
.explain { display: flex; flex-direction: column; gap: 16px; padding-top: 4px; }
.model { font-size: var(--t-18); line-height: 1.6; max-width: 66ch; margin-top: 4px; }
.evidence { margin: 0; background: var(--sunken); border-radius: var(--r-md); padding: 18px 20px; display: flex; flex-direction: column; gap: 12px; }
.ev-head { display: flex; justify-content: space-between; gap: 4px 12px; flex-wrap: wrap; align-items: baseline; }
.ev-head .label { color: var(--teal); }
.ev-date { font-size: var(--t-12); color: var(--muted); font-variant-numeric: tabular-nums; }
.evidence blockquote { margin: 0; font-family: var(--font-quote); font-size: var(--t-18); line-height: 1.65; color: var(--ink); max-width: 66ch; overflow-wrap: anywhere; }
.ev-src { display: flex; justify-content: space-between; align-items: center; gap: 8px 16px; flex-wrap: wrap; font-size: var(--t-13); }
.ev-src a.url { color: var(--muted); text-decoration: none; min-width: 0; }
.ev-src a.url:hover { color: var(--teal); text-decoration: underline; }
.ev-note { font-size: var(--t-13); color: var(--muted); }
.rate { display: flex; align-items: center; gap: 10px 16px; flex-wrap: wrap; padding-top: 16px; border-top: 1px solid var(--line); }
.rate p { font-weight: 600; font-size: var(--t-14); flex: 1 1 240px; }
.rate .seg button[aria-checked="true"][data-rate="review"] { color: var(--copper-text); }
.rate .seg button[aria-checked="true"][data-rate="know"] { color: var(--right); }
.q-foot { display: flex; align-items: center; gap: 10px; margin: 4px -32px 0; padding: 14px 32px; border-top: 1px solid var(--line); background: var(--surface); border-radius: 0 0 var(--r-lg) var(--r-lg); position: sticky; bottom: 0; z-index: 5; }
.q-foot .hints { flex: 1; display: flex; gap: 14px; justify-content: center; font-size: var(--t-12); color: var(--muted); flex-wrap: wrap; }
.q-foot .hints span { display: inline-flex; gap: 5px; align-items: center; }
.q-foot .grow { display: none; }
.empty { padding: 32px; border: 1px dashed var(--line-strong); border-radius: var(--r-lg); display: flex; flex-direction: column; gap: 10px; align-items: flex-start; }
.empty h2 { font-size: var(--t-22); }

/* ---------- Context column ---------- */
.context { display: flex; flex-direction: column; gap: 16px; position: sticky; top: 84px; }
.panel { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); padding: 18px; display: flex; flex-direction: column; gap: 12px; }
.panel.plain { background: transparent; border-color: transparent; padding: 4px 4px 0; }
.big { display: flex; align-items: baseline; gap: 8px; flex-wrap: wrap; }
.big strong { font-family: var(--font-display); font-size: var(--t-36); font-weight: 800; letter-spacing: -.02em; font-variant-numeric: tabular-nums; line-height: 1; }
.big span { color: var(--muted); font-size: var(--t-14); }
.stack { display: flex; height: 8px; border-radius: 8px; overflow: hidden; background: var(--sunken); }
.stack i { display: block; height: 100%; }
.legend { display: grid; grid-template-columns: auto 1fr auto; gap: 6px 8px; margin: 0; font-size: var(--t-13); align-items: center; }
.legend dt { width: 10px; height: 10px; border-radius: 3px; }
.legend dd { margin: 0; }
.legend dd.v { text-align: right; font-variant-numeric: tabular-nums; font-weight: 700; }
.c-right { background: var(--right); } .c-wrong { background: var(--wrong); } .c-know { background: var(--teal); } .c-review { background: var(--copper); }
.panel .btn { width: 100%; }
.terms { margin: 0; display: flex; flex-direction: column; gap: 12px; }
.terms dt { font-weight: 700; font-size: var(--t-14); }
.terms dd { margin: 2px 0 0; color: var(--muted); font-size: var(--t-14); line-height: 1.5; }
.panel .more { font-size: var(--t-13); font-weight: 600; background: none; border: 0; padding: 0; color: var(--teal); text-decoration: underline; text-underline-offset: 3px; align-self: flex-start; }
.panel.note h3 { font-size: var(--t-16); }
.panel.note p { font-size: var(--t-14); color: var(--muted); }
.keys { display: grid; grid-template-columns: auto 1fr; gap: 8px 10px; font-size: var(--t-13); color: var(--muted); align-items: center; margin: 0; }
.keys dt { display: flex; gap: 3px; }
.keys dd { margin: 0; }
.reset-row { display: flex; flex-direction: column; gap: 6px; font-size: var(--t-12); color: var(--muted); }

/* ---------- Reading views ---------- */
.view-pane { min-width: 0; display: flex; flex-direction: column; gap: 16px; }
.view-pane .search { flex: none; }
.view-head { display: flex; flex-direction: column; gap: 6px; }
.view-head h1 { font-size: var(--t-28); font-weight: 800; letter-spacing: -.02em; }
.view-head p { color: var(--muted); max-width: 70ch; }
.view-tools { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.view-tools select { height: 44px; border: 1px solid var(--line-strong); border-radius: var(--r-md); background: var(--surface); padding: 0 12px; min-width: 0; max-width: 100%; flex: 1 1 320px; }
.reading { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); padding: 24px 28px; display: flex; flex-direction: column; gap: 12px; }
.reading > h2 { font-size: var(--t-22); font-weight: 700; }
.reading ul { margin: 0; padding-left: 20px; display: flex; flex-direction: column; gap: 6px; }
.reading details summary { cursor: pointer; font-weight: 600; color: var(--teal); }
.reading details[open] summary { margin-bottom: 10px; }
.reading .actions { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; padding-top: 4px; }
.reading .meta { font-size: var(--t-13); color: var(--muted); }
.reading.flag { background: var(--copper-soft); border-color: transparent; }
.reading.flag .evidence { background: var(--surface); }
.section-title { font-size: var(--t-22); font-weight: 800; margin-top: 16px; }
.source-body { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); padding: 28px 32px; font-size: var(--t-16); line-height: 1.7; overflow-wrap: anywhere; }
.source-body h1 { font-size: var(--t-28); margin-bottom: 12px; }
.source-body h2 { font-size: var(--t-22); margin: 32px 0 10px; }
.source-body h3 { font-size: var(--t-18); margin: 24px 0 8px; }
.source-body h4, .source-body h5 { font-size: var(--t-16); margin: 18px 0 6px; }
.source-body p, .source-body ul, .source-body ol { margin: 10px 0; }
.source-body table { width: 100%; border-collapse: collapse; table-layout: fixed; font-size: var(--t-13); margin: 18px 0; }
.source-body th, .source-body td { border: 1px solid var(--line); padding: 10px; vertical-align: top; overflow-wrap: anywhere; }
.source-body th { background: var(--sunken); text-align: left; }
.source-body pre { font: var(--t-13)/1.6 var(--font-mono); white-space: pre-wrap; overflow-wrap: anywhere; background: var(--sunken); border-radius: var(--r-md); padding: 16px; max-width: 100%; overflow: hidden; }
.source-body code { font-family: var(--font-mono); font-size: .9em; }
.source-body aside, .source-body blockquote { background: var(--sunken); border-radius: var(--r-md); padding: 14px 18px; margin: 16px 0; }
.source-body .media-link { font-size: var(--t-13); display: block; }
.source-body [id] { scroll-margin-top: 80px; }
.source-body .highlight { background: var(--highlight); box-shadow: 0 0 0 6px var(--highlight); border-radius: 3px; }
.source-body svg, .source-body img { max-width: 100%; height: auto; }
.def-grid { display: flex; flex-direction: column; gap: 12px; }
.def-card h2 { font-size: var(--t-18); }
.def-card > p { color: var(--ink); }

/* ---------- Page footer ---------- */
.page-foot { border-top: 1px solid var(--line); margin: 8px 32px 0; padding-block: 20px 40px; font-size: var(--t-13); color: var(--muted); display: flex; flex-direction: column; gap: 8px; }
.page-foot details summary { cursor: pointer; font-weight: 600; color: var(--teal); }
.page-foot details p { margin-top: 8px; max-width: 90ch; }

/* ---------- Filter sheet ---------- */
dialog.sheet { border: 0; padding: 0; margin: 0 0 0 auto; height: 100vh; max-height: 100vh; width: min(420px, 100vw); background: var(--surface); color: var(--ink); box-shadow: var(--shadow); }
dialog.sheet::backdrop { background: rgb(10 22 28 / 45%); }
.sheet-in { height: 100%; display: flex; flex-direction: column; }
.sheet-head { display: flex; align-items: center; justify-content: space-between; padding: 18px 20px; border-bottom: 1px solid var(--line); }
.sheet-head h2 { font-size: var(--t-18); }
.sheet-body { flex: 1; overflow-y: auto; padding: 8px 20px 20px; }
.sheet fieldset { border: 0; margin: 0; padding: 14px 0 4px; display: flex; flex-direction: column; gap: 8px; }
.sheet legend { padding: 0; margin-bottom: 4px; font-size: var(--t-12); font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.choice { display: flex; align-items: center; gap: 12px; padding: 10px 12px; border: 1px solid var(--line); border-radius: var(--r-md); cursor: pointer; font-size: var(--t-14); }
.choice:hover { border-color: var(--line-strong); }
.choice:has(input:checked) { border-color: var(--teal); background: var(--mint); }
.choice input { accent-color: var(--teal); width: 18px; height: 18px; margin: 0; flex-shrink: 0; }
.choice span { flex: 1; }
.choice small { color: var(--muted); font-size: var(--t-13); font-variant-numeric: tabular-nums; }
.sheet-foot { display: flex; gap: 10px; padding: 14px 20px calc(14px + env(safe-area-inset-bottom, 0px)); border-top: 1px solid var(--line); }
.sheet-foot .btn-primary { flex: 1; }

/* ---------- Breakpoints (app) ---------- */
@media (max-width: 1180px) {
  .content { grid-template-columns: minmax(0, 760px); }
  .context { position: static; display: grid; grid-template-columns: 1fr 1fr; align-items: start; }
  .context .keys-panel { display: none; }
}
@media (max-width: 880px) {
  .app { grid-template-columns: minmax(0, 1fr); }
  .rail { position: fixed; inset: 0 auto 0 0; z-index: 50; width: min(320px, 86vw); height: 100%; transform: translateX(-102%); visibility: hidden; transition: transform .2s ease, visibility 0s .2s; padding-top: calc(16px + env(safe-area-inset-top, 0px)); }
  .rail.is-open { transform: none; visibility: visible; transition: transform .2s ease; box-shadow: 0 0 40px rgb(0 0 0 / 30%); }
  .scrim { position: fixed; inset: 0; z-index: 40; background: rgb(10 22 28 / 45%); border: 0; }
  .scrim.is-open { display: block; }
  .rail-views { display: flex; flex-direction: column; gap: 2px; padding-bottom: 14px; border-bottom: 1px solid var(--rail-line); }
  .rail-views button { text-align: left; border: 0; background: transparent; color: var(--rail-fg); min-height: 42px; padding: 0 10px; border-radius: var(--r-sm); font-weight: 600; font-size: var(--t-16); }
  .rail-views button[aria-selected="true"] { background: var(--rail-2); color: #fff; }
  .topbar { padding: 0 8px 0 4px; gap: 6px; height: 56px; }
  .topbar .menu-btn { display: inline-grid; }
  .top-brand { display: block; font-family: var(--font-display); font-weight: 700; font-size: var(--t-16); min-width: 0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: var(--ink); text-decoration: none; }
  .views { display: none; }
  .top-progress { display: inline-block; font-size: var(--t-13); color: var(--muted); font-variant-numeric: tabular-nums; white-space: nowrap; }
  .top-progress b { color: var(--ink); }
  .top-actions .gh, .lbl-dl { display: none; }
  #dl-btn { padding: 0 10px; }
  .popover { position: fixed; left: 16px; right: 16px; top: 64px; width: auto; }
  .content { padding-inline: 16px; padding-block: 14px 32px; gap: 20px; }
  body.has-bar .content { padding-bottom: calc(var(--bar-h) + 32px + env(safe-area-inset-bottom, 0px)); }
  .session { gap: 8px; }
  .session .seg { width: 100%; }
  .session .seg button { flex: 1; padding: 0 8px; }
  .search { flex: 1 1 0; }
  .filter-btn { padding: 0 12px; }
  .filter-btn .lbl { display: none; }
  .qcard { padding: 20px 18px 4px; gap: 18px; border-radius: 14px; }
  .q-meta { flex-direction: column; gap: 8px; }
  .q-tags { order: -1; width: 100%; }
  .q-tags .icon-btn { margin-left: auto; }
  .q-text { font-size: var(--t-22); }
  .opt { grid-template-columns: 28px minmax(0, 1fr); padding: 12px; gap: 12px; }
  .opt-key { width: 28px; height: 28px; font-size: var(--t-13); margin-top: -2px; }
  .opt-state { grid-column: 2; }
  .opt-state:empty { display: none; }
  .model, .evidence blockquote { font-size: var(--t-16); }
  .evidence { padding: 16px; margin: 0 -4px; }
  .verdict { grid-template-columns: 20px minmax(0, 1fr); }
  .verdict .btn { grid-column: 2; justify-self: start; }
  .rate .seg { width: 100%; }
  .rate .seg button { flex: 1; padding: 0 8px; white-space: normal; line-height: 1.2; }
  .q-foot { position: fixed; left: 0; right: 0; bottom: 0; z-index: 30; margin: 0; border-radius: 0; padding: 10px 16px calc(10px + env(safe-area-inset-bottom, 0px)); box-shadow: 0 -6px 20px rgb(21 45 58 / 8%); }
  .q-foot .hints { display: none; }
  .q-foot .btn { min-height: 46px; }
  .q-foot .btn-prev { padding: 0 12px; }
  .q-foot .btn-prev .lbl { display: none; }
  .q-foot .grow { display: block; flex: 1; }
  .context { grid-template-columns: minmax(0, 1fr); }
  .reading, .source-body { padding: 20px 18px; }
  .source-body table { font-size: var(--t-12); }
  .source-body th, .source-body td { padding: 6px; }
  .page-foot { margin: 0 16px; }
  dialog.sheet { margin: auto 0 0; width: 100vw; max-width: 100vw; height: auto; max-height: 88vh; border-radius: 18px 18px 0 0; }
}

/* ---------- Home ---------- */
.wrap { max-width: 1160px; margin: 0 auto; padding-inline: 32px; }
.site-head { border-bottom: 1px solid var(--line); }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; height: 68px; }
.site-head .brand { color: var(--ink); padding: 0; }
.site-head .brand svg { width: 32px; height: 32px; }
.site-head .brand b { font-size: var(--t-16); }
.site-nav { display: flex; gap: 4px; align-items: center; }
.site-nav a { color: var(--muted); text-decoration: none; font-weight: 600; font-size: var(--t-14); padding: 8px 10px; border-radius: var(--r-sm); }
.site-nav a:hover { color: var(--ink); background: var(--sunken); }
.resume { background: var(--mint); }
.resume .wrap { display: flex; align-items: center; gap: 10px 16px; flex-wrap: wrap; padding-block: 12px; }
.resume p { font-size: var(--t-14); flex: 1 1 320px; }
.resume b { font-variant-numeric: tabular-nums; }
.resume .btn { min-height: 38px; }
.hero { padding-block: 56px 48px; }
.hero .wrap { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 480px); gap: 56px; align-items: start; }
.hero-copy { display: flex; flex-direction: column; gap: 22px; padding-top: 8px; }
.hero h1 { font-size: var(--t-48); font-weight: 800; letter-spacing: -.03em; line-height: 1.08; max-width: 15ch; }
.hero-lede { font-size: var(--t-18); color: var(--muted); max-width: 52ch; }
.hero-ctas { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-ctas .btn { min-height: 50px; padding: 0 22px; font-size: var(--t-16); }
.hero-meta { display: flex; gap: 8px 18px; flex-wrap: wrap; font-size: var(--t-14); color: var(--muted); }
.hero-meta span { display: inline-flex; align-items: center; gap: 6px; }
.hero-meta svg { width: 16px; height: 16px; color: var(--teal); }
.try { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--shadow); padding: 22px; display: flex; flex-direction: column; gap: 14px; }
.try-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; }
.try h2 { font-size: var(--t-22); font-weight: 700; line-height: 1.3; }
.try .options { gap: 8px; }
.try .opt { grid-template-columns: 26px minmax(0, 1fr); gap: 12px; padding: 10px 12px; font-size: var(--t-14); }
.try .opt-key { width: 26px; height: 26px; border-radius: 5px; font-size: var(--t-13); margin-top: -2px; }
.try-hint { font-size: var(--t-13); color: var(--muted); }
.try-result { display: flex; flex-direction: column; gap: 12px; }
.try-verdict { font-size: var(--t-14); }
.try-verdict b { color: var(--right); }
.try-verdict.no b { color: var(--wrong); }
.try .evidence { padding: 14px 16px; gap: 8px; }
.try .evidence blockquote { font-size: var(--t-16); }
.try-foot { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; font-size: var(--t-13); color: var(--muted); }
.facts { border-block: 1px solid var(--line); }
.facts dl { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); margin: 0; }
.facts dl > div { padding: 20px 20px 20px 0; display: flex; flex-direction: column; gap: 2px; }
.facts dl > div + div { padding-left: 20px; border-left: 1px solid var(--line); }
.facts dt { order: 2; font-size: var(--t-14); color: var(--muted); }
.facts dd { margin: 0; font: 800 var(--t-28)/1.1 var(--font-display); letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.facts dd.small { font-size: var(--t-18); padding-top: 8px; }
section.block { padding-block: 64px 8px; }
.block-head { display: flex; flex-direction: column; gap: 8px; margin-bottom: 28px; max-width: 62ch; }
.block-head h2 { font-size: var(--t-28); font-weight: 800; letter-spacing: -.02em; }
.block-head p { color: var(--muted); }
.formats { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.format { border-top: 3px solid var(--ink); padding-top: 20px; display: flex; flex-direction: column; gap: 16px; }
.format h3 { font-size: var(--t-22); font-weight: 800; display: flex; align-items: center; gap: 10px; }
.format h3 svg { width: 22px; height: 22px; color: var(--teal); }
.format .best { font-size: var(--t-14); color: var(--muted); }
.format .best b { color: var(--ink); }
.steps { list-style: none; counter-reset: s; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 12px; }
.steps li { counter-increment: s; display: grid; grid-template-columns: 28px minmax(0, 1fr); gap: 12px; align-items: baseline; }
.steps li::before { content: counter(s); font: 700 var(--t-13)/24px var(--font-display); width: 24px; height: 24px; border-radius: 50%; text-align: center; background: var(--sunken); color: var(--ink); }
.format .btn { align-self: flex-start; }
.cover { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 48px; align-items: start; }
.split { display: flex; height: 14px; border-radius: 4px; overflow: hidden; gap: 2px; margin-bottom: 10px; }
.split i, .split-legend i { display: block; }
.split i { height: 100%; }
.a1 { background: var(--ink); } .a2 { background: var(--teal); } .a3 { background: var(--right); }
.split-legend { display: flex; gap: 8px 22px; flex-wrap: wrap; font-size: var(--t-14); color: var(--muted); margin-bottom: 28px; }
.split-legend span { display: inline-flex; align-items: center; gap: 8px; }
.split-legend i { width: 10px; height: 10px; border-radius: 2px; }
.split-legend b { color: var(--ink); font-variant-numeric: tabular-nums; }
.area-block + .area-block { margin-top: 22px; }
.area-block h3 { font: 700 var(--t-12)/1.4 var(--font-body); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); margin-bottom: 6px; }
.bars { list-style: none; margin: 0; padding: 0; }
.bars a { display: grid; grid-template-columns: minmax(0, 220px) minmax(0, 1fr) 40px; gap: 14px; align-items: center; padding: 7px 8px; margin-inline: -8px; border-radius: var(--r-sm); color: var(--ink); text-decoration: none; font-size: var(--t-14); }
.bars a:hover { background: var(--sunken); }
.bars .name small { color: var(--muted); margin-left: 6px; }
.bars .track { height: 10px; background: var(--sunken); border-radius: 3px; overflow: hidden; }
.bars a:hover .track { background: var(--line); }
.bars .fill { display: block; height: 100%; border-radius: 3px; }
.bars .v { text-align: right; font-variant-numeric: tabular-nums; font-weight: 700; }
.cover-side { display: flex; flex-direction: column; gap: 14px; }
.side-note { border: 1px solid var(--line); border-radius: var(--r-lg); padding: 18px; display: flex; flex-direction: column; gap: 8px; background: var(--surface); }
.side-note h3 { font-size: var(--t-16); font-weight: 700; }
.side-note p { font-size: var(--t-14); color: var(--muted); }
.downloads { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.downloads li { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 4px 20px; align-items: center; padding: 16px 0; border-bottom: 1px solid var(--line); }
.downloads b { font-weight: 700; }
.downloads small { grid-column: 1; color: var(--muted); font-size: var(--t-14); }
.downloads .files { grid-column: 2; grid-row: 1 / 3; display: flex; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
.downloads .file-link { font-size: var(--t-13); padding: 7px 10px; }
.site-foot { margin-top: 72px; border-top: 1px solid var(--line); }
.site-foot .wrap { padding-block: 24px 40px; display: flex; justify-content: space-between; gap: 12px 32px; flex-wrap: wrap; font-size: var(--t-13); color: var(--muted); }
.site-foot p { max-width: 70ch; }
.lost { padding-block: 80px; display: flex; flex-direction: column; gap: 16px; align-items: flex-start; }
.lost h1 { font-size: var(--t-36); font-weight: 800; }

@media (max-width: 960px) {
  .hero .wrap { grid-template-columns: minmax(0, 1fr); gap: 36px; }
  .hero h1 { max-width: 18ch; }
  .cover { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .cover-side { display: grid; grid-template-columns: 1fr 1fr; }
  .facts dl { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .facts dl > div:nth-child(4) { padding-left: 0; border-left: 0; }
  .facts dl > div:nth-child(n+4) { border-top: 1px solid var(--line); }
}
@media (max-width: 640px) {
  .wrap { padding-inline: 16px; }
  .site-head .wrap { height: 58px; }
  .site-nav a:not(.gh) { display: none; }
  .resume .wrap { padding-block: 10px; gap: 8px 10px; }
  .resume p { flex-basis: 100%; }
  .hero { padding-block: 28px 36px; }
  .hero h1 { font-size: var(--t-36); }
  .hero-lede { font-size: var(--t-16); }
  .hero-ctas .btn { flex: 1 1 100%; }
  .try { padding: 18px 16px; }
  .try h2 { font-size: var(--t-18); }
  .facts dl { grid-template-columns: 1fr 1fr; }
  .facts dl > div, .facts dl > div + div { padding: 14px 0; border-left: 0; }
  .facts dl > div:nth-child(even) { padding-left: 16px; border-left: 1px solid var(--line); }
  .facts dl > div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .facts dl > div:last-child { grid-column: 1 / -1; padding-left: 0; border-left: 0; }
  .facts dd { font-size: var(--t-22); }
  section.block { padding-block: 48px 0; }
  .block-head h2 { font-size: var(--t-22); }
  .formats { grid-template-columns: minmax(0, 1fr); gap: 36px; }
  .format .btn { align-self: stretch; }
  .bars a { grid-template-columns: minmax(0, 1fr) 40px; gap: 4px 12px; }
  .bars .name { grid-column: 1; }
  .bars .v { grid-column: 2; grid-row: 1; }
  .bars .track { grid-column: 1 / -1; }
  .cover-side { grid-template-columns: minmax(0, 1fr); }
  .downloads li { grid-template-columns: minmax(0, 1fr); }
  .downloads .files { grid-column: 1; grid-row: auto; justify-content: flex-start; padding-top: 6px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}
@media print {
  .rail, .topbar, .session, .scope, .q-foot, .context, .page-foot, .site-nav, .resume { display: none !important; }
  .app { display: block; }
  .content { display: block; padding: 0; }
}