/* Wordwork's palette and type (static/app.css), so the two apps read as siblings. */
:root{
  --ground:#F7F8FA; --surface:#FFFFFF; --surface-2:#F1F2F7;
  --ink:#171B22; --ink-2:#4A4F5E; --ink-3:#7A8095;
  --line:#E2E4EC; --line-strong:#CFD3E0;
  --accent:#4B3FCF; --accent-soft:#EEECFB;
  --good:#1E7A5A; --good-soft:#E4F4EC;
  --miss:#C4442E; --miss-soft:#FBEAE6;
  --gold:#B4791B; --gold-soft:#FBF1DE;
}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;background:var(--ground);color:var(--ink);
  font-family:"IBM Plex Sans",ui-sans-serif,system-ui,-apple-system,sans-serif;
  font-size:15px;line-height:1.5;-webkit-font-smoothing:antialiased}
h1,h2,h3{margin:0;text-wrap:balance}
button{font:inherit}
.lbl{font-size:10.5px;text-transform:uppercase;letter-spacing:.09em;
  color:var(--ink-3);font-weight:600}
.hidden{display:none!important}
button:focus-visible{outline:2px solid var(--accent);outline-offset:2px}

/* ---------- chrome ---------- */
.bar,.top{display:flex;align-items:center;gap:16px;padding:14px 40px;
  border-bottom:1px solid var(--line);background:var(--surface)}
.bar .n{font-family:Fraunces,Georgia,serif;font-size:19px;font-weight:600}
.top .count{margin-left:auto}
.navlink{color:var(--ink-2);font-size:14px;background:none;border:0;cursor:pointer;
  padding:6px 12px;border-radius:7px;margin-left:-12px}
.navlink:hover{background:var(--surface-2);color:var(--ink)}
.screen{min-height:100vh;display:flex;flex-direction:column}
.count{font-size:13px;color:var(--ink-3);font-variant-numeric:tabular-nums}
.pbar{width:190px;height:6px;background:var(--surface-2);border-radius:99px;overflow:hidden}
.pbar i{display:block;height:100%;background:var(--accent);border-radius:99px;
  transition:width .35s cubic-bezier(.4,0,.2,1)}
.page{padding:34px 40px 56px;display:flex;flex-direction:column;align-items:center;gap:24px;
  max-width:1060px;width:100%;margin:0 auto}

/* ---------- home ---------- */
.hero{text-align:center;display:flex;flex-direction:column;gap:10px;align-items:center}
.hero h1{font-family:Fraunces,Georgia,serif;font-size:44px;font-weight:600;letter-spacing:-.02em}
.hero p{margin:0;color:var(--ink-2);font-size:16px;max-width:540px}
.levels{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:10px;width:100%;max-width:760px}
.lvl{background:var(--surface);border:1.5px solid var(--line-strong);border-radius:12px;
  padding:14px 12px 12px;cursor:pointer;text-align:left;display:flex;flex-direction:column;gap:2px;
  transition:border-color .12s,background .12s}
.lvl:hover{border-color:var(--accent)}
.lvl b{font-family:Fraunces,Georgia,serif;font-size:26px;font-weight:600;line-height:1.1}
.lvl .r{font-size:13.5px;color:var(--ink-2)}
.lvl .s{font-size:12px;color:var(--ink-3);font-variant-numeric:tabular-nums;margin-top:6px}
.lvl .s i{display:block;height:4px;border-radius:99px;background:var(--surface-2);margin-top:5px;overflow:hidden}
.lvl .s i u{display:block;height:100%;background:var(--accent)}
.lvl.in{border-color:#B9B3EE;background:#F6F5FD}
.lvl.in b{color:#6D62DC}
.streak{display:inline-flex;align-items:center;gap:7px;font-size:13.5px;color:var(--gold);
  background:var(--gold-soft);padding:5px 13px;border-radius:999px;font-weight:600}
.streak b{font-size:15px;font-variant-numeric:tabular-nums}
.streak span{color:var(--ink-3);font-weight:500;margin-left:4px}
.sc.gold b{color:var(--gold)}
.lvl[aria-checked="true"]{border-color:var(--accent);background:var(--accent-soft)}
.lvl[aria-checked="true"] b{color:var(--accent)}
.go{background:var(--accent);color:#fff;border:0;border-radius:12px;padding:16px 44px;
  font-size:18px;font-weight:600;cursor:pointer;box-shadow:0 10px 26px -14px rgba(75,63,207,.9)}
.go:hover{background:#3A31A6}
.go:disabled{opacity:.55;cursor:default;box-shadow:none}

.panel{background:var(--surface);border:1px solid var(--line);border-radius:12px;
  padding:20px 22px;display:flex;flex-direction:column;gap:14px;width:100%}
.phead{display:flex;align-items:baseline;gap:14px;flex-wrap:wrap}
.phead h2{font-family:Fraunces,Georgia,serif;font-size:26px;font-weight:600;margin-right:auto}
.tot{display:flex;gap:22px;flex-wrap:wrap}
.tot div{display:flex;flex-direction:column}
.tot b{font-family:Fraunces,Georgia,serif;font-size:26px;font-weight:600;line-height:1.1;
  font-variant-numeric:tabular-nums}
.ixnote{font-size:13px;color:var(--ink-3);line-height:1.45}

/* progress grid: chapter x band */
#h-progress{width:100%;min-width:0}
.gridwrap{overflow-x:auto;max-width:100%}
.pg td.nm{position:sticky;left:0;background:var(--surface);z-index:1}
table.pg{width:100%;border-collapse:collapse;font-size:14px;min-width:680px}
.pg th{font-size:10.5px;text-transform:uppercase;letter-spacing:.09em;color:var(--ink-3);
  font-weight:600;padding:0 6px 8px;text-align:center}
.pg th:first-child{text-align:left;padding-left:0}
.pg td{border-top:1px solid var(--line);padding:6px;text-align:center;vertical-align:middle}
.pg td.nm{text-align:left;padding-left:0;white-space:nowrap}
.pg tr.ch td.nm button{background:none;border:0;padding:4px 0;cursor:pointer;font-weight:600;
  color:var(--ink);display:flex;align-items:center;gap:7px}
.pg tr.ch td.nm button span{color:var(--ink-3);font-size:11px;width:10px;display:inline-block;
  transition:transform .15s}
.pg tr.ch.open td.nm button span{transform:rotate(90deg)}
.pg tr.sec td{border-top:1px dashed var(--line);background:#FBFBFD}
.pg tr.sec td.nm{background:#FBFBFD}
.pg tr.sec td.nm{padding-left:17px;font-size:13px;color:var(--ink-2);white-space:normal}
.pg tr.sec td.nm em{font-style:normal;color:var(--ink-3);font-size:12px;margin-right:6px;
  font-variant-numeric:tabular-nums}
.pg tr.all td{border-top:1.5px solid var(--line-strong);font-weight:600}
.pg td.colall{border-left:1px solid var(--line)}
.cell{display:inline-flex;flex-direction:column;align-items:center;min-width:64px;
  padding:5px 6px;border-radius:8px;line-height:1.2}
.cell b{font-size:15px;font-variant-numeric:tabular-nums}
.cell small{font-size:11.5px;color:var(--ink-3);font-variant-numeric:tabular-nums}
.cell.none b{color:var(--line-strong);font-weight:500}
.cell.q0{background:var(--miss-soft)} .cell.q0 b{color:var(--miss)}
.cell.q1{background:var(--gold-soft)} .cell.q1 b{color:var(--gold)}
.cell.q2{background:var(--good-soft)} .cell.q2 b{color:var(--good)}
.cell.na{opacity:.35}
.legend{display:flex;gap:14px;flex-wrap:wrap;font-size:12.5px;color:var(--ink-2)}
.legend span{display:flex;align-items:center;gap:6px}
.legend s{width:12px;height:12px;border-radius:3px;display:block}
.recent{display:flex;gap:8px;flex-wrap:wrap}
.recent span{background:var(--surface-2);border:1px solid var(--line);border-radius:8px;
  padding:4px 10px;font-size:12.5px;color:var(--ink-2);font-variant-numeric:tabular-nums}

/* ---------- problem ---------- */
.work{flex:1;display:flex;flex-direction:column;align-items:center;gap:20px;
  padding:30px 40px 60px}
.prob{width:100%;max-width:760px;background:var(--surface);border:1px solid var(--line);
  border-radius:14px;padding:26px 30px;display:flex;flex-direction:column;gap:14px;
  box-shadow:0 1px 2px rgba(23,27,34,.04),0 18px 40px -30px rgba(23,27,34,.4)}
.prob .src{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.tag{font-size:11px;letter-spacing:.08em;text-transform:uppercase;font-weight:700;
  padding:3px 9px;border-radius:999px;background:var(--surface-2);color:var(--ink-3)}
.tag.new{background:var(--accent-soft);color:var(--accent)}
.md{font-size:16.5px;line-height:1.6}
.md p{margin:0 0 .7em}
.md p:last-child{margin-bottom:0}
.md ul,.md ol{margin:0 0 .7em;padding-left:22px}
.md img{display:block;max-width:100%;max-height:340px;margin:10px auto;height:auto}
.md .katex-display{margin:.6em 0;overflow-x:auto;overflow-y:hidden;padding:2px 0}
.md .katex{font-size:1.06em}
.md table.tab{border-collapse:collapse;margin:10px auto;font-size:15px}
.md table.tab td{border:1px solid var(--line-strong);padding:4px 12px;text-align:center}
.choices{display:flex;flex-direction:column;gap:8px;margin-top:4px}
.choices.grid{display:grid;grid-template-columns:repeat(5,minmax(0,1fr))}
.opt{display:flex;align-items:center;gap:12px;padding:11px 14px;min-height:50px;
  background:var(--surface);border:1.5px solid var(--line-strong);border-radius:10px;
  font-size:16px;color:var(--ink);cursor:pointer;text-align:left;
  transition:border-color .12s,background .12s}
.opt:hover:not(:disabled){border-color:var(--accent)}
.opt .k{width:26px;height:26px;flex:none;border-radius:6px;background:var(--surface-2);
  color:var(--ink-3);font-size:12.5px;font-weight:600;display:flex;align-items:center;
  justify-content:center;font-family:"IBM Plex Mono",monospace}
.opt .v img{max-height:120px;max-width:100%;display:block}
.opt.sel{border-color:var(--accent);background:var(--accent-soft)}
.opt.sel .k{background:var(--accent);color:#fff}
.opt.right{border-color:var(--good);background:var(--good-soft)}
.opt.right .k{background:var(--good);color:#fff}
.opt.wrong{border-color:var(--miss);background:var(--miss-soft)}
.opt.wrong .k{background:var(--miss);color:#fff}
.opt.dim{opacity:.5}
.opt:disabled{cursor:default}
.acts{display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.btn{background:var(--accent);color:#fff;border:0;border-radius:9px;
  padding:11px 22px;font-size:15px;font-weight:600;cursor:pointer}
.btn:hover{background:#3A31A6}
.btn:disabled{opacity:.45;cursor:default}
.btn.ghost{background:var(--surface);color:var(--ink-2);border:1px solid var(--line-strong)}
.btn.ghost:hover{background:var(--surface-2)}
.hint{font-size:12.5px;color:var(--ink-3)}
.kbd{font-family:"IBM Plex Mono",monospace;font-size:11.5px;background:var(--surface);
  border:1px solid var(--line-strong);border-bottom-width:2px;border-radius:5px;
  padding:1px 6px;color:var(--ink-2)}

/* ---------- result ---------- */
.verdict{width:100%;max-width:760px;border-radius:12px;padding:16px 20px;display:flex;
  align-items:center;gap:18px;flex-wrap:wrap}
.verdict.ok{background:var(--good-soft);color:var(--good)}
.verdict.no{background:var(--miss-soft);color:var(--miss)}
.verdict h3{font-family:Fraunces,Georgia,serif;font-size:24px;font-weight:600}
.verdict .what{color:var(--ink-2);font-size:14.5px}
.clock{margin-left:auto;text-align:right;color:var(--ink-2);font-size:13px;line-height:1.35}
.clock .lbl{display:block}
.clock b{display:block;font-family:Fraunces,Georgia,serif;font-size:26px;font-weight:600;
  color:var(--ink);font-variant-numeric:tabular-nums}
.sol{width:100%;max-width:760px;background:var(--surface);border:1px solid var(--line);
  border-radius:14px;padding:22px 28px;display:flex;flex-direction:column;gap:14px}
.sol h4{margin:0;font-family:Fraunces,Georgia,serif;font-size:20px;font-weight:600}
.sol .md{font-size:15.5px}
.traps{background:var(--gold-soft);border-radius:10px;padding:12px 16px}
.traps .md{font-size:14.5px}
.traps .lbl{color:var(--gold);display:block;margin-bottom:4px}
details.more{border-top:1px solid var(--line);padding-top:12px}
details.more summary{cursor:pointer;color:var(--ink-2);font-size:14px;font-weight:600}
details.more .alt{border-left:2px solid var(--line-strong);padding-left:14px;margin-top:12px}
details.more .alt .md{font-size:14.5px}
.book{width:100%;max-width:760px;display:flex;gap:16px;align-items:center;background:var(--accent-soft);
  border-radius:12px;padding:16px 20px}
.book .ic{width:42px;height:52px;flex:none;border-radius:4px 7px 7px 4px;background:var(--accent);
  color:#fff;display:flex;align-items:center;justify-content:center;font-family:Fraunces,Georgia,serif;
  font-weight:700;font-size:15px;box-shadow:inset 4px 0 0 rgba(0,0,0,.18)}
.book .t{display:flex;flex-direction:column;gap:2px;font-size:14px;color:var(--ink-2)}
.book .t b{color:var(--ink);font-size:15.5px}
.book.none{background:var(--surface-2)}
.book.none .ic{background:var(--ink-3)}

/* ---------- summary ---------- */
.done{width:100%;max-width:760px;display:flex;flex-direction:column;align-items:center;gap:20px;
  text-align:center}
.done h2{font-family:Fraunces,Georgia,serif;font-size:40px;font-weight:600}
.score{display:flex;gap:12px;flex-wrap:wrap;justify-content:center}
.sc{background:var(--surface);border:1px solid var(--line);border-radius:12px;
  padding:14px 24px;min-width:140px}
.sc b{display:block;font-family:Fraunces,Georgia,serif;font-size:32px;font-weight:600;
  font-variant-numeric:tabular-nums;line-height:1.1}
.sc.g b{color:var(--good)}
table.recap{width:100%;border-collapse:collapse;font-size:14.5px;text-align:left}
.recap td{border-top:1px solid var(--line);padding:9px 6px}
.recap td.n{text-align:right;font-variant-numeric:tabular-nums;color:var(--ink-2)}
.recap .mark{font-weight:700;width:28px}
.recap .mark.ok{color:var(--good)} .recap .mark.no{color:var(--miss)}
.recap a{color:var(--accent);cursor:pointer;text-decoration:none}
.recap a:hover{text-decoration:underline}
.recap small{color:var(--ink-3);display:block;font-size:12.5px}

@media (max-width:760px){
  .bar,.top{padding:12px 16px}
  .page,.work{padding-left:16px;padding-right:16px}
  .levels{grid-template-columns:repeat(5,minmax(56px,1fr));gap:6px}
  .lvl{padding:10px 8px} .lvl .r{font-size:12px} .lvl .s{display:none}
  .prob,.sol{padding:18px 16px}
  .hero h1{font-size:32px}
  .pbar{width:90px}
  .choices.grid{grid-template-columns:repeat(3,minmax(0,1fr))}
  .clock{margin-left:0;text-align:left}
  table.pg{min-width:600px}
  .pg tr.sec td.nm{white-space:nowrap}
  .tot{gap:16px}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important}}