:root {
  --ink: #18201b;
  --ink2: #4a554e;
  --muted: #6b766f;
  --line: #dde3de;
  --soft: #f3f6f3;
  --bg: #ffffff;
  --acc: #14532d;
  --acc2: #0f3f22;
  --ok: #157a42;
  --okbg: #eaf6ee;
  --no: #b42318;
  --nobg: #fdf0ee;
  --mark: #f6d55c;
  --r: 8px;
  font-family: "Public Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  -webkit-text-size-adjust: 100%;
}
* { box-sizing: border-box; }
body { margin: 0; font-size: 16px; line-height: 1.6; }
a { color: var(--acc); text-underline-offset: 2px; }
a:hover { color: var(--acc2); }
img { max-width: 100%; height: auto; }
.w { max-width: 1180px; margin: 0 auto; padding: 0 20px; }

/* header */
.top { border-bottom: 1px solid var(--line); background: var(--bg); }
.top .w { display: flex; align-items: center; gap: 28px; min-height: 60px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--ink); text-decoration: none; font-size: 17px; letter-spacing: -0.01em; }
.brand img { border-radius: 6px; }
.top nav { display: flex; gap: 22px; flex-wrap: wrap; }
.top nav a { color: var(--ink2); text-decoration: none; font-size: 15px; padding: 18px 0; border-bottom: 2px solid transparent; }
.top nav a:hover { color: var(--ink); }
.top nav a[aria-current] { color: var(--ink); border-bottom-color: var(--acc); }

/* home intro */
.intro { padding: 28px 0 18px; max-width: 820px; }
h1, h2, h3 { text-wrap: balance; }
p, li { text-wrap: pretty; }
h1 { font-size: 34px; line-height: 1.2; margin: 0 0 10px; letter-spacing: -0.02em; }
.lede { font-size: 18px; color: var(--ink2); margin: 0; max-width: 70ch; }
h2 { font-size: 24px; line-height: 1.3; margin: 44px 0 12px; letter-spacing: -0.01em; }
h3 { font-size: 18px; margin: 26px 0 8px; }
.prose { max-width: 72ch; }
.prose p, .prose li { color: var(--ink); }

/* desk: board + side */
.desk { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 28px; align-items: start; }
.board { min-width: 0; }
.side { position: sticky; top: 16px; border: 1px solid var(--line); border-radius: var(--r); padding: 18px; background: var(--bg); }
.side h2 { font-size: 17px; margin: 0 0 2px; }
.fine { font-size: 13.5px; color: var(--muted); margin: 4px 0 0; line-height: 1.5; }

.tabs { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; margin-bottom: 12px; }
.tabrow { display: flex; gap: 4px; background: var(--soft); border-radius: var(--r); padding: 4px; flex-wrap: wrap; }
.tab { font: inherit; font-size: 14.5px; border: 0; background: transparent; color: var(--ink2); padding: 7px 12px; border-radius: 6px; cursor: pointer; display: inline-flex; align-items: center; gap: 6px; white-space: nowrap; transition: background .15s, color .15s; }
.tab:hover { color: var(--ink); background: #e7ece8; }
.tab.on { background: var(--bg); color: var(--ink); font-weight: 600; box-shadow: 0 1px 2px rgba(24, 32, 27, .12); }
.lock { font-size: 11.5px; font-weight: 600; color: var(--acc); border: 1px solid #b9d3c1; border-radius: 4px; padding: 0 5px; line-height: 18px; }
.secsel { font: inherit; font-size: 14.5px; padding: 7px 10px; border: 1px solid #8a958d; border-radius: 6px; background: var(--bg); color: var(--ink); max-width: 100%; }

.card { border: 1px solid var(--line); border-radius: var(--r); padding: 22px 24px 24px; background: var(--bg); transition: opacity .18s ease, transform .18s ease; }
.card.enter { opacity: 0; transform: translateY(6px); }
.qhead { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; font-size: 14px; color: var(--muted); }
.qn { font-weight: 600; color: var(--ink); }
.qsec { flex: 1 1 auto; }
.clock { font-variant-numeric: tabular-nums; font-weight: 600; color: var(--ink); border: 1px solid var(--line); border-radius: 6px; padding: 1px 8px; }
.clock.low { color: var(--no); border-color: #f1b9b2; }
.flag { font: inherit; font-size: 13.5px; border: 1px solid var(--line); background: var(--bg); border-radius: 6px; padding: 2px 9px; cursor: pointer; color: var(--ink2); }
.flag.on { background: #fff7d6; border-color: #e8cf6d; color: #6b5300; }
.bar { height: 4px; background: var(--soft); border-radius: 2px; margin: 12px 0 18px; overflow: hidden; }
.bar i { display: block; height: 100%; background: var(--acc); border-radius: 2px; transition: width .3s ease; }
.stem { font-size: 17px; line-height: 1.65; margin: 0 0 14px; max-width: 75ch; }
.hint { font-size: 14px; font-weight: 600; color: var(--acc); margin: -4px 0 12px; }

.opts { display: grid; gap: 8px; }
.opt { font: inherit; text-align: left; display: grid; grid-template-columns: 30px minmax(0, 1fr); gap: 12px; align-items: start; width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: var(--r); background: var(--bg); color: var(--ink); cursor: pointer; line-height: 1.5; transition: border-color .12s, background .12s, transform .08s; }
.opt:hover:not(:disabled) { border-color: #9fb3a6; background: #fafcfa; }
.opt:active:not(:disabled) { transform: scale(.995); }
.opt .k { width: 28px; height: 28px; border-radius: 50%; border: 1.5px solid #aab6ae; display: grid; place-items: center; font-size: 13.5px; font-weight: 700; color: var(--ink2); }
.opt[role="checkbox"] .k { border-radius: 6px; }
.opt.sel { border-color: var(--acc); background: #f2f8f4; }
.opt.sel .k { background: var(--acc); border-color: var(--acc); color: #fff; }
.opt:disabled { cursor: default; }
.opt.right { border-color: var(--ok); background: var(--okbg); }
.opt.right .k { background: var(--ok); border-color: var(--ok); color: #fff; }
.opt.wrong { border-color: var(--no); background: var(--nobg); }
.opt.wrong .k { background: var(--no); border-color: var(--no); color: #fff; }
.opt.dim { color: var(--ink2); }
.why { display: block; font-size: 14.5px; color: var(--ink2); margin-top: 6px; padding-left: 10px; border-left: 2px solid var(--line); }
.opt.wrong .why { border-left-color: #eaa59c; }

.expl { margin-top: 16px; padding: 14px 16px; border-radius: var(--r); background: var(--soft); border-left: 4px solid var(--ok); }
.expl.no { border-left-color: var(--no); }
.expl p { margin: 0 0 8px; max-width: 75ch; }
.expl p:last-child { margin-bottom: 0; }
.verdict { font-weight: 700; }
.src { font-size: 14px; color: var(--muted); word-break: break-word; }

.actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 18px; align-items: center; }
.actions .end { margin-left: auto; }
.btn { font: inherit; font-size: 15.5px; font-weight: 600; border: 1px solid var(--acc); background: var(--acc); color: #fff; padding: 10px 18px; border-radius: var(--r); cursor: pointer; transition: background .15s, transform .08s, opacity .15s; }
.btn:hover:not(:disabled) { background: var(--acc2); }
.btn:active:not(:disabled) { transform: translateY(1px); }
.btn:disabled { background: #d5dcd7; border-color: #d5dcd7; color: #4a554e; cursor: not-allowed; }
.btn.ghost { background: var(--bg); color: var(--ink); border-color: #c4cec7; }
.btn.ghost:hover:not(:disabled) { background: var(--soft); }
.link { font: inherit; font-size: 14.5px; background: none; border: 0; color: var(--acc); text-decoration: underline; cursor: pointer; padding: 0; margin-top: 14px; }

.nav { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 20px; padding-top: 16px; border-top: 1px solid var(--line); }
.dot { font: inherit; font-size: 12.5px; width: 32px; height: 30px; border: 1px solid var(--line); background: var(--bg); border-radius: 5px; cursor: pointer; color: var(--ink2); font-variant-numeric: tabular-nums; }
.dot.done { background: #e4efe7; border-color: #b9d3c1; color: var(--ink); }
.dot.flag { box-shadow: inset 0 -3px 0 #e2b93b; }
.dot.cur { border-color: var(--acc); color: var(--acc); font-weight: 700; }

/* side map */
.map { list-style: none; margin: 14px 0 0; padding: 0; display: grid; gap: 4px; }
.map li { position: relative; }
.map button { font: inherit; display: grid; grid-template-columns: 24px minmax(0, 1fr); gap: 10px; width: 100%; text-align: left; border: 0; background: transparent; padding: 8px 6px 12px; border-radius: 6px; cursor: pointer; color: var(--ink); }
.map button:hover { background: var(--soft); }
.mn { width: 24px; height: 24px; border-radius: 50%; background: var(--soft); display: grid; place-items: center; font-size: 12.5px; font-weight: 700; color: var(--ink2); margin-top: 1px; }
.mt b { display: block; font-size: 14.5px; font-weight: 600; line-height: 1.35; }
.mt small { display: block; font-size: 12.5px; color: var(--muted); line-height: 1.4; }
.mbar { position: absolute; left: 40px; right: 6px; bottom: 5px; height: 3px; background: var(--soft); border-radius: 2px; overflow: hidden; }
.mbar i { display: block; height: 100%; background: var(--ok); transition: width .4s ease; }
.own { margin-top: 14px; padding-top: 14px; border-top: 1px solid var(--line); }
.own b { display: block; font-size: 16px; }
.own span { font-size: 14px; color: var(--ink2); }
.own ul { margin: 6px 0 12px; padding-left: 18px; font-size: 14px; color: var(--ink2); }
.own .btn { width: 100%; }

/* results and wall */
.score { display: flex; align-items: baseline; gap: 14px; flex-wrap: wrap; margin-bottom: 14px; }
.score b { font-size: 44px; line-height: 1; letter-spacing: -0.02em; font-variant-numeric: tabular-nums; }
.score span { color: var(--ink2); }
table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-weight: 600; color: var(--ink2); font-size: 14px; background: var(--soft); }
.meter { display: flex; align-items: center; gap: 8px; max-width: 240px; }
.meter .tr { flex: 1 1 auto; min-width: 48px; height: 8px; background: var(--soft); border-radius: 4px; overflow: hidden; }
.meter .tr i { display: block; height: 100%; background: var(--acc); border-radius: 4px; transition: width .4s ease; }
.meter em { font-style: normal; font-variant-numeric: tabular-nums; font-size: 14px; }
.review { display: grid; gap: 8px; }
.rv { border: 1px solid var(--line); border-radius: var(--r); padding: 10px 14px; }
.rv summary { cursor: pointer; font-weight: 600; font-size: 15px; }
.rvopts { list-style: none; padding: 0; margin: 8px 0; display: grid; gap: 6px; }
.rvopts li { padding: 6px 10px; border-radius: 6px; }
.rvopts li.right { background: var(--okbg); }
.rvopts li.wrong { background: var(--nobg); }
.wall h2 { margin-top: 0; font-size: 22px; }
.wall.small { margin: 18px 0 4px; padding: 16px 18px; border: 1px solid #b9d3c1; border-radius: var(--r); background: #f4f9f5; }
.wall.small h3 { margin-top: 0; }
.wt { margin: 14px 0; }
.gets { padding-left: 20px; margin: 10px 0; }
.facts2 { list-style: none; padding: 12px 14px; margin: 14px 0 4px; background: var(--soft); border-radius: var(--r); display: grid; gap: 4px; font-size: 15px; }
.facts2 li { padding-left: 20px; position: relative; }
.facts2 li::before { content: ""; position: absolute; left: 2px; top: .55em; width: 9px; height: 5px; border-left: 2px solid var(--ok); border-bottom: 2px solid var(--ok); transform: rotate(-45deg); }
.nav-s { display: none; }
.gets li { margin: 4px 0; }
.topics span { color: var(--ink2); }
.buyrow { margin-top: 14px; }
.btn.buy { font-size: 16px; padding: 12px 20px; }
.signin { margin-top: 16px; font-size: 15px; }
.signin summary { cursor: pointer; color: var(--ink2); }
.signin .row { display: flex; gap: 8px; margin-top: 8px; flex-wrap: wrap; }
.signin input { font: inherit; padding: 9px 11px; border: 1px solid #8a958d; border-radius: var(--r); flex: 1 1 220px; min-width: 0; }
.banner { background: var(--okbg); border: 1px solid #b9d3c1; padding: 10px 14px; border-radius: var(--r); margin: 0 0 12px; }

/* content pages */
.tw { overflow-x: auto; margin: 12px 0; }
.facts { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border: 1px solid var(--line); border-radius: var(--r); margin: 28px 0 0; }
.facts div { padding: 14px 16px; border-right: 1px solid var(--line); }
.facts div:last-child { border-right: 0; }
.facts b { display: block; font-size: 22px; letter-spacing: -0.01em; }
.facts span { font-size: 14px; color: var(--ink2); }
figure { margin: 18px 0; }
figure img { border: 1px solid var(--line); border-radius: var(--r); display: block; }
figcaption { font-size: 13.5px; color: var(--muted); margin-top: 6px; }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 28px; align-items: start; }
.crumbs { font-size: 14px; color: var(--muted); margin: 22px 0 6px; }
.crumbs a { color: var(--muted); }
.page { padding-bottom: 20px; }
.page > * { max-width: 820px; }
.page > .figs { max-width: 1000px; }
.figs { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr)); gap: 18px; align-items: start; }
.figs figure { margin: 8px 0; }
.page h1 { margin-top: 4px; }
.sec { scroll-margin-top: 16px; }
.sq { border: 1px solid var(--line); border-radius: var(--r); padding: 16px 18px; margin: 14px 0; }
.sq ol { list-style: upper-alpha; padding-left: 24px; }
.sq details { margin-top: 8px; }
.sq summary { cursor: pointer; font-weight: 600; color: var(--acc); }
.cta { border: 1px solid #b9d3c1; background: #f4f9f5; border-radius: var(--r); padding: 16px 18px; margin: 26px 0; }
.cta p { margin: 0 0 10px; }
a.btn { display: inline-block; text-decoration: none; }
a.btn:hover { color: #fff; }

footer { border-top: 1px solid var(--line); margin-top: 56px; padding: 22px 0 36px; font-size: 14px; color: var(--muted); }
footer p { max-width: 90ch; margin: 0 0 8px; }
footer a { color: var(--ink2); }

@media (max-width: 960px) {
  .desk { grid-template-columns: minmax(0, 1fr); }
  .side { position: static; }
  .split { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 640px) {
  .w { padding: 0 14px; }
  .top .w { gap: 6px 18px; padding-top: 10px; }
  .top nav { gap: 16px; flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none; width: 100%; }
  .top nav::-webkit-scrollbar { display: none; }
  .top nav a { white-space: nowrap; }
  .tabrow { flex-wrap: nowrap; width: 100%; justify-content: space-between; }
  .lock { display: none; }
  .nav-l { display: none; }
  .nav-s { display: inline; }
  .card .actions:has(.btn) { position: sticky; bottom: 0; background: var(--bg); margin: 14px -14px -18px; padding: 10px 14px 12px; border-top: 1px solid var(--line); border-radius: 0 0 var(--r) var(--r); z-index: 2; }
  .secsel { width: 100%; }
  .top nav a { padding: 6px 0 10px; font-size: 14.5px; }
  h1 { font-size: 26px; }
  .lede { font-size: 16px; }
  .upd { display: none; }
  .intro { padding: 18px 0 12px; }
  .card { padding: 16px 14px 18px; }
  .stem { font-size: 16px; }
  .opt { padding: 11px 12px; gap: 10px; grid-template-columns: 28px minmax(0, 1fr); }
  .facts { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .facts div:nth-child(2) { border-right: 0; }
  .facts div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .actions .end { margin-left: 0; }
  .tabs { margin-bottom: 10px; }
  .tab { padding: 7px 9px; font-size: 14px; }
}
@media (max-width: 380px) {
  .tabrow { overflow-x: auto; scrollbar-width: none; justify-content: flex-start; }
  .tab { padding: 7px 7px; font-size: 13.5px; }
}
.btn:focus-visible, .tab:focus-visible, .opt:focus-visible, .dot:focus-visible, .map button:focus-visible, .flag:focus-visible, .link:focus-visible, a:focus-visible { outline: 2px solid var(--acc); outline-offset: 2px; }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}
.upd { font-size: 14.5px; color: var(--ink2); margin: 10px 0 0; padding-left: 10px; border-left: 3px solid var(--mark); max-width: 80ch; }
.wide-fig { max-width: 980px; }
code { font-size: .92em; background: var(--soft); padding: 1px 4px; border-radius: 4px; overflow-wrap: anywhere; }
.pn { display: flex; justify-content: space-between; gap: 12px 24px; flex-wrap: wrap; margin: 28px 0 8px; padding-top: 16px; border-top: 1px solid var(--line); }
.pn a { font-weight: 600; }
@media (max-width: 640px) {
  table.st thead { display: none; }
  table.st, table.st tbody, table.st tr, table.st td { display: block; width: 100%; }
  table.st tr { border-bottom: 1px solid var(--line); padding: 10px 0; }
  table.st td { border: 0; padding: 2px 0; }
  table.st td:first-child { font-weight: 600; }
  table.st td[data-label]:not(:first-child)::before { content: attr(data-label) ": "; color: var(--muted); font-weight: 600; }
}
.desk ~ .tw, .desk ~ h2, .desk ~ p { max-width: 820px; }
.sq, .sec p, .sec li, .sec td, .stem, .opt .t, .expl, .why { overflow-wrap: anywhere; }
.src { overflow-wrap: break-word; }
code { overflow-wrap: break-word; word-break: normal; }
.page p, .page ul, .page ol, .prose p, .prose li { max-width: 72ch; }
.page h1, .page h2 { max-width: 820px; }
table.kv td:first-child { width: 32%; }
.doc { max-width: none !important; }
.toc { border-left: 3px solid var(--line); padding: 2px 0 2px 16px; margin: 18px 0 8px; }
.toc b { display: block; font-size: 15px; margin-bottom: 6px; }
.toc ol { margin: 0; padding-left: 20px; }
.toc li { font-size: 15px; margin: 4px 0; }
.toc .buybox { display: none; }
@media (min-width: 1200px) {
  .doc { display: grid; grid-template-columns: minmax(0, 820px) 280px; column-gap: 48px; align-items: start; }
  .doc > .doc-main { grid-column: 1; grid-row: 1; min-width: 0; }
  .doc > .toc { grid-column: 2; grid-row: 1; position: sticky; top: 16px; max-height: calc(100vh - 32px); overflow-y: auto; margin-top: 4px; }
  .toc li { font-size: 14px; }
  .toc .buybox { display: block; margin-top: 18px; padding: 14px; border: 1px solid var(--line); border-radius: var(--r); }
  .toc .buybox p { font-size: 14px; margin: 4px 0 10px; }
  .toc .buybox .btn { width: 100%; text-align: center; }
}
.doc-main > * { max-width: 820px; }
.doc-main > .figs { max-width: 1000px; }