/* Layout: sidebar (desktop) / bottom tab bar (mobile) · content column 880px · cards on a cool paper ground.
   Palette: paper-cool ground, ink text, cerulean accent for action, signal orange only for streak/XP. */
:root{
  --bg:#EFF3F6;--surface:#FFFFFF;--surface-2:#E6ECF1;--ink:#0F1B26;--muted:#566677;--line:#D5DEE6;
  --accent:#0B6E99;--accent-ink:#FFFFFF;--accent-soft:#D6EBF5;
  --flame:#D9500B;--flame-soft:#FBE6D8;--gold:#9A6B00;
  --ok:#157A3C;--ok-soft:#DDF2E4;--bad:#B9261C;--bad-soft:#FBE2DF;
  --shadow:0 1px 2px rgba(15,27,38,.06),0 6px 20px rgba(15,27,38,.05);
  --f-display:"Bricolage Grotesque","Segoe UI",system-ui,sans-serif;
  --f-body:"Hanken Grotesk","Segoe UI",system-ui,sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,Menlo,Consolas,monospace;
}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){
  --bg:#0B141D;--surface:#121F2B;--surface-2:#1A2B3A;--ink:#E6EEF4;--muted:#8DA2B3;--line:#243645;
  --accent:#5CC0E8;--accent-ink:#06202D;--accent-soft:#16384A;
  --flame:#FF8A4C;--flame-soft:#3A2314;--gold:#E3B341;
  --ok:#4CC27A;--ok-soft:#12301F;--bad:#FF7B72;--bad-soft:#3B1B1D;
  --shadow:0 1px 2px rgba(0,0,0,.3),0 6px 20px rgba(0,0,0,.25);color-scheme:dark}}
:root[data-theme="dark"]{
  --bg:#0B141D;--surface:#121F2B;--surface-2:#1A2B3A;--ink:#E6EEF4;--muted:#8DA2B3;--line:#243645;
  --accent:#5CC0E8;--accent-ink:#06202D;--accent-soft:#16384A;
  --flame:#FF8A4C;--flame-soft:#3A2314;--gold:#E3B341;
  --ok:#4CC27A;--ok-soft:#12301F;--bad:#FF7B72;--bad-soft:#3B1B1D;
  --shadow:0 1px 2px rgba(0,0,0,.3),0 6px 20px rgba(0,0,0,.25);color-scheme:dark}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.55 var(--f-body);-webkit-font-smoothing:antialiased}
h1,h2,h3{font-family:var(--f-display);margin:0;letter-spacing:-.01em;text-wrap:balance}
button{font:inherit;color:inherit;cursor:pointer}
a{color:var(--accent)}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:6px}
svg{display:block}
.mono{font-family:var(--f-mono)}
.num{font-variant-numeric:tabular-nums}

/* ---------- shell ---------- */
.shell{min-height:100vh;display:grid;grid-template-columns:232px 1fr}
.side{position:sticky;top:0;height:100vh;display:flex;flex-direction:column;gap:6px;padding:20px 14px 16px max(14px,env(safe-area-inset-left,0px));background:var(--surface);border-right:1px solid var(--line)}
.brand{display:flex;align-items:center;gap:10px;padding:4px 10px 18px}
.brand-mark{width:34px;height:34px;border-radius:10px;background:var(--accent);color:var(--accent-ink);display:grid;place-items:center;font:800 15px var(--f-display);letter-spacing:-.02em}
.brand b{font:700 17px var(--f-display);display:block;line-height:1.1}
.brand span{font:500 11px var(--f-mono);color:var(--muted);letter-spacing:.06em;text-transform:uppercase}
.nav{display:flex;flex-direction:column;gap:2px}
.nav a{display:flex;align-items:center;gap:12px;padding:10px 12px;border-radius:10px;color:var(--muted);text-decoration:none;font-weight:600;font-size:15px}
.nav a:hover{background:var(--surface-2);color:var(--ink)}
.nav a[aria-current=page]{background:var(--accent-soft);color:var(--accent)}
.nav svg{width:20px;height:20px;flex:none;stroke:currentColor;fill:none;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
.side-foot{margin-top:auto;display:flex;flex-direction:column;gap:10px}
.lvl{padding:12px;border:1px solid var(--line);border-radius:12px;background:var(--bg)}
.lvl-top{display:flex;justify-content:space-between;align-items:baseline;gap:8px}
.lvl-top b{font:700 14px var(--f-display)}
.lvl-top span{font:500 11px var(--f-mono);color:var(--muted)}
.track{height:6px;border-radius:99px;background:var(--surface-2);overflow:hidden;margin-top:8px}
.track>i{display:block;height:100%;background:var(--accent);border-radius:99px;transition:width .5s cubic-bezier(.2,.8,.2,1)}
.themebtn{display:flex;align-items:center;gap:10px;width:100%;padding:9px 12px;border:1px solid var(--line);border-radius:10px;background:none;color:var(--muted);font-size:14px;font-weight:600}
.themebtn:hover{color:var(--ink);background:var(--surface-2)}
.themebtn svg{width:18px;height:18px;stroke:currentColor;fill:none;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
.main{min-width:0;padding:32px max(24px,env(safe-area-inset-right,0px)) 72px 32px}
.page{max-width:880px;margin:0 auto;animation:rise .35s cubic-bezier(.2,.8,.2,1)}
@keyframes rise{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* mobile top bar + bottom tabs */
.topbar{display:none}
@media (max-width:860px){
  .shell{display:block}
  .side{display:none}
  body::before{content:"";position:fixed;inset:0 0 auto;height:env(safe-area-inset-top,0px);background:var(--surface);z-index:30}
  .topbar{display:flex;position:sticky;top:env(safe-area-inset-top,0px);z-index:20;align-items:center;justify-content:space-between;gap:10px;padding:10px max(16px,env(safe-area-inset-right,0px)) 10px max(16px,env(safe-area-inset-left,0px));background:var(--surface);border-bottom:1px solid var(--line)}
  .topbar .brand{padding:0}
  .topbar .chips{display:flex;gap:8px;align-items:center}
  .main{padding:20px max(16px,env(safe-area-inset-right,0px)) calc(92px + env(safe-area-inset-bottom,0px)) max(16px,env(safe-area-inset-left,0px))}
  .tabs{display:flex;position:fixed;left:0;right:0;bottom:0;z-index:25;background:var(--surface);border-top:1px solid var(--line);padding:6px max(6px,env(safe-area-inset-right,0px)) calc(6px + env(safe-area-inset-bottom,0px)) max(6px,env(safe-area-inset-left,0px))}
  .tabs a{flex:1;min-width:0;display:flex;flex-direction:column;align-items:center;gap:2px;padding:6px 2px;border-radius:10px;color:var(--muted);text-decoration:none;font:600 10.5px var(--f-body)}
  .tabs a[aria-current=page]{color:var(--accent);background:var(--accent-soft)}
  .tabs svg{width:22px;height:22px;stroke:currentColor;fill:none;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
  .tabs span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:100%}
}
@media (min-width:861px){.tabs{display:none}}

/* ---------- primitives ---------- */
.card{background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:20px;box-shadow:var(--shadow);min-width:0}
.card+.card,.stack>*+*{margin-top:16px}
.grid{display:grid;gap:16px;min-width:0}
.g2{grid-template-columns:repeat(2,minmax(0,1fr))}
.g3{grid-template-columns:repeat(3,minmax(0,1fr))}
.g4{grid-template-columns:repeat(4,minmax(0,1fr))}
@media (max-width:760px){.g3,.g4{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:480px){.g2,.g3,.g4{grid-template-columns:1fr}.g-keep2{grid-template-columns:repeat(2,minmax(0,1fr))}}
.eyebrow{font:600 11.5px var(--f-mono);letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.title{font-size:clamp(26px,4vw,36px);font-weight:700;line-height:1.1}
.h2{font-size:20px;font-weight:700}
.sub{color:var(--muted);margin:6px 0 0}
.muted{color:var(--muted)}
.row{display:flex;gap:12px;align-items:center;flex-wrap:wrap}
.between{justify-content:space-between}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border:0;border-radius:12px;padding:12px 20px;background:var(--accent);color:var(--accent-ink);font:700 15px var(--f-body);transition:transform .12s,filter .12s}
.btn:hover{filter:brightness(1.08)}.btn:active{transform:translateY(1px)}
.btn[disabled]{opacity:.45;cursor:not-allowed;filter:none}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--line)}
.btn.ghost:hover{background:var(--surface-2);filter:none}
.btn.sm{padding:8px 14px;font-size:14px;border-radius:10px}
.btn.lg{padding:15px 28px;font-size:16px}
.btn.danger{color:var(--bad)}
.pill{display:inline-flex;align-items:center;gap:6px;padding:3px 10px;border-radius:99px;background:var(--accent-soft);color:var(--accent);font:600 12px var(--f-mono)}
.pill.flame{background:var(--flame-soft);color:var(--flame)}
.pill.ok{background:var(--ok-soft);color:var(--ok)}
.pill.bad{background:var(--bad-soft);color:var(--bad)}
.pill svg{width:13px;height:13px}
.seg{display:inline-flex;padding:3px;gap:2px;border-radius:12px;background:var(--surface-2);flex-wrap:wrap}
.seg button{border:0;background:none;padding:7px 14px;border-radius:9px;font-weight:600;font-size:14px;color:var(--muted)}
.seg button[aria-pressed=true]{background:var(--surface);color:var(--ink);box-shadow:0 1px 3px rgba(0,0,0,.12)}
.lbl{display:block;font:600 11.5px var(--f-mono);letter-spacing:.07em;text-transform:uppercase;color:var(--muted);margin:0 0 8px}
select,input[type=search],textarea{font:inherit;padding:10px 12px;border:1px solid var(--line);border-radius:10px;background:var(--bg);color:var(--ink);min-width:0;max-width:100%}
input[type=search]{width:100%}
textarea{width:100%;font:13px/1.4 var(--f-mono)}
.ring{position:relative;display:grid;place-items:center;flex:none}
.ring svg{transform:rotate(-90deg)}
.ring .rt{position:absolute;inset:0;display:grid;place-items:center;text-align:center;font:700 var(--rs,18px) var(--f-display);line-height:1}
.ring .rt small{display:block;font:500 10px var(--f-mono);color:var(--muted);margin-top:3px;letter-spacing:.04em}
.ring circle{transition:stroke-dashoffset .9s cubic-bezier(.2,.8,.2,1)}

/* ---------- home ---------- */
.hero{display:flex;justify-content:space-between;gap:20px;align-items:flex-end;flex-wrap:wrap;margin-bottom:24px}
.stat{display:flex;gap:16px;align-items:center}
.stat .big{font:700 34px var(--f-display);line-height:1}
.stat .cap{font-size:13px;color:var(--muted);margin-top:4px}
.bars{display:flex;align-items:flex-end;gap:5px;height:56px;margin-top:12px}
.bars i{flex:1;border-radius:4px 4px 2px 2px;background:var(--surface-2);min-height:4px}
.bars i.on{background:var(--accent)}.bars i.today{background:var(--flame)}
.quick{display:flex;flex-direction:column;gap:6px;align-items:flex-start;text-align:left;width:100%;padding:16px;border:1px solid var(--line);border-radius:14px;background:var(--surface);transition:border-color .15s,transform .15s}
.quick:hover{border-color:var(--accent);transform:translateY(-2px)}
.quick .ic{width:36px;height:36px;border-radius:10px;background:var(--accent-soft);color:var(--accent);display:grid;place-items:center;margin-bottom:6px}
.quick .ic svg{width:19px;height:19px;stroke:currentColor;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
.quick b{font:700 16px var(--f-display)}
.quick span{font-size:13.5px;color:var(--muted)}
.quick[disabled]{opacity:.5;cursor:not-allowed}.quick[disabled]:hover{transform:none;border-color:var(--line)}
.wk{display:flex;align-items:center;gap:14px;padding:12px 0;border-top:1px solid var(--line)}
.wk:first-child{border-top:0}
.wk .nm{flex:1;min-width:0}
.wk .nm b{display:block;font-weight:700;overflow-wrap:anywhere}
.wk .nm span{font-size:13px;color:var(--muted)}

/* ---------- module picker ---------- */
.mods{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:10px}
.mod{display:flex;gap:12px;align-items:center;text-align:left;padding:12px;border:1.5px solid var(--line);border-radius:14px;background:var(--surface);min-width:0}
.mod:hover{border-color:var(--accent)}
.mod[aria-pressed=true]{border-color:var(--accent);background:var(--accent-soft)}
.mod .t{min-width:0}
.mod b{display:block;font:700 14px var(--f-body);line-height:1.25;overflow-wrap:anywhere}
.mod small{font:500 11.5px var(--f-mono);color:var(--muted)}
.chips{display:flex;gap:6px;flex-wrap:wrap}
.chip{padding:7px 14px;border:1px solid var(--line);border-radius:99px;background:var(--surface);font-weight:600;font-size:14px;color:var(--muted)}
.chip[aria-pressed=true]{background:var(--ink);color:var(--surface);border-color:var(--ink)}

/* ---------- runner ---------- */
.run{max-width:720px;margin:0 auto}
.runbar{display:flex;align-items:center;gap:12px;margin-bottom:16px}
.runbar .grow{flex:1;min-width:0}
.dots{display:flex;gap:3px}
.dots i{flex:1;height:6px;border-radius:99px;background:var(--surface-2)}
.dots i.ok{background:var(--ok)}.dots i.bad{background:var(--bad)}.dots i.cur{background:var(--accent)}.dots i.ans{background:var(--accent)}
.timer{font:700 16px var(--f-mono)}
.timer.low{color:var(--bad)}
.q{padding:24px}
.qmeta{display:flex;justify-content:space-between;gap:8px;margin-bottom:14px;align-items:center}
.qtext{font:600 clamp(18px,2.6vw,22px)/1.4 var(--f-display);margin:0 0 20px;white-space:pre-wrap;overflow-wrap:anywhere}
.opt{display:flex;gap:14px;align-items:flex-start;width:100%;text-align:left;padding:14px 16px;margin-top:10px;border:1.5px solid var(--line);border-radius:14px;background:var(--surface);transition:border-color .12s,background .12s,transform .12s}
.opt:hover:not(:disabled){border-color:var(--accent);transform:translateX(2px)}
.opt .k{flex:none;width:28px;height:28px;border-radius:8px;background:var(--surface-2);display:grid;place-items:center;font:700 13px var(--f-mono);color:var(--muted)}
.opt .tx{padding-top:2px;overflow-wrap:anywhere}
.opt.sel{border-color:var(--accent);background:var(--accent-soft)}
.opt.sel .k{background:var(--accent);color:var(--accent-ink)}
.opt.ok{border-color:var(--ok);background:var(--ok-soft)}.opt.ok .k{background:var(--ok);color:#fff}
.opt.bad{border-color:var(--bad);background:var(--bad-soft)}.opt.bad .k{background:var(--bad);color:#fff}
.opt.bad{animation:shake .32s}
.opt:disabled{cursor:default}
@keyframes shake{25%{transform:translateX(-5px)}75%{transform:translateX(5px)}}
.fb{margin-top:18px;padding:14px 16px;border-radius:14px;animation:rise .25s ease-out}
.fb.ok{background:var(--ok-soft)}.fb.bad{background:var(--bad-soft)}
.fb b{display:flex;gap:8px;align-items:center;font:700 16px var(--f-display)}
.fb.ok b{color:var(--ok)}.fb.bad b{color:var(--bad)}
.fb p{margin:6px 0 0;font-size:15px}
.xp{font:700 12px var(--f-mono);color:var(--flame);animation:pop .5s ease-out}
@keyframes pop{from{transform:scale(.6);opacity:0}60%{transform:scale(1.2)}to{transform:scale(1);opacity:1}}
.star{border:0;background:none;padding:4px;color:var(--muted)}
.star svg{width:22px;height:22px;stroke:currentColor;fill:none;stroke-width:1.9;stroke-linejoin:round}
.star.on{color:var(--gold)}.star.on svg{fill:currentColor}
.kbd{font:600 11px var(--f-mono);padding:2px 6px;border:1px solid var(--line);border-radius:6px;color:var(--muted)}
.palette{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:14px}
.palette button{width:34px;height:34px;border-radius:9px;border:1.5px solid var(--line);background:var(--surface);font:600 12px var(--f-mono);color:var(--muted)}
.palette button.ans{background:var(--accent-soft);border-color:var(--accent);color:var(--accent)}
.palette button.cur{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}
.runfoot{display:flex;justify-content:space-between;gap:10px;margin-top:18px;flex-wrap:wrap;align-items:center}

/* ---------- result ---------- */
.res{text-align:center;padding:32px 20px}
.res .ring{margin:0 auto 12px}
.res h2{font-size:26px}
.review-item{padding:14px 0;border-top:1px solid var(--line)}
.review-item:first-child{border-top:0}
.review-item .yours{color:var(--bad);font-size:14px;margin-top:6px}
.review-item .right{color:var(--ok);font-size:14px;margin-top:2px;font-weight:600}
.review-item .why{color:var(--muted);font-size:14px;margin-top:6px}

/* ---------- badges / table ---------- */
.badge{display:flex;gap:12px;align-items:center;padding:12px;border:1px solid var(--line);border-radius:14px;background:var(--surface)}
.badge .bi{width:42px;height:42px;border-radius:12px;display:grid;place-items:center;background:var(--surface-2);color:var(--muted);flex:none}
.badge .bi svg{width:22px;height:22px;stroke:currentColor;fill:none;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
.badge.got .bi{background:var(--flame-soft);color:var(--flame)}
.badge:not(.got){opacity:.6}
.badge b{display:block;font-size:14.5px}.badge span{font-size:13px;color:var(--muted)}
.tbl{width:100%;border-collapse:collapse;font-size:14.5px}
.tbl th{font:600 11px var(--f-mono);letter-spacing:.07em;text-transform:uppercase;color:var(--muted);text-align:left;padding:8px 6px;border-bottom:1px solid var(--line)}
.tbl td{padding:10px 6px;border-bottom:1px solid var(--line);vertical-align:middle}
.tbl .bar{height:6px;border-radius:99px;background:var(--surface-2);min-width:70px;overflow:hidden}
.tbl .bar i{display:block;height:100%;background:var(--accent)}
.tblwrap{overflow-x:auto}

/* ---------- cheat / docs ---------- */
.cs-item{padding:14px 0;border-top:1px solid var(--line)}
.cs-item:first-child{border-top:0}
.cs-item .f{overflow-x:auto;padding:8px 0}
.docs{display:grid;grid-template-columns:200px minmax(0,1fr);gap:16px;align-items:start}
@media (max-width:760px){.docs{grid-template-columns:1fr}}
.docnav{display:flex;flex-direction:column;gap:2px;padding:8px}
.docnav button{text-align:left;background:none;border:0;padding:8px 10px;border-radius:9px;font-size:14px;font-weight:600;color:var(--muted)}
.docnav button.on{background:var(--accent-soft);color:var(--accent)}
.md{overflow-wrap:anywhere}
.md pre,.slide{background:var(--bg);border:1px solid var(--line);border-radius:10px;padding:12px;overflow:auto;font:13px/1.5 var(--f-mono);white-space:pre-wrap}
.md code{background:var(--bg);padding:1px 6px;border-radius:5px;font:.88em var(--f-mono)}
.md pre code{padding:0;background:none}
.md h1,.md h2,.md h3,.md h4{margin:20px 0 8px}
.slide{margin:10px 0;font-family:var(--f-body);font-size:14px}
.slide small{display:block;color:var(--muted);font:600 11px var(--f-mono);margin-bottom:6px}
.hit{padding:10px 0;border-top:1px solid var(--line);font-size:14px;cursor:pointer}
mark{background:#FFE08A;color:#1a1a1a;border-radius:3px;padding:0 2px}
.empty{padding:28px 12px;text-align:center;color:var(--muted)}

#toast{position:fixed;left:50%;bottom:calc(92px + env(safe-area-inset-bottom,0px));transform:translate(-50%,16px);background:var(--ink);color:var(--bg);padding:10px 18px;border-radius:12px;font-weight:600;font-size:14px;opacity:0;pointer-events:none;transition:.22s;z-index:50;max-width:90vw}
#toast.on{opacity:1;transform:translate(-50%,0)}
@media (min-width:861px){#toast{bottom:28px}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}html{scroll-behavior:auto}}
:where(svg.i){stroke:currentColor;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;width:18px;height:18px;flex:none}
.res .ring .rt{font-size:40px}.res .ring .rt small{font-size:12px}
.fb b .pill{margin-left:4px}
.grid>*{margin-top:0!important}
.dock{position:sticky;bottom:16px;z-index:5;box-shadow:0 -4px 24px rgba(15,27,38,.12),var(--shadow)}
@media (max-width:860px){.dock{bottom:calc(78px + env(safe-area-inset-bottom,0px))}}