:root{
  --bg:#EEF3F8; --paper:#FFFFFF; --grid:rgba(22,35,58,.07); --ink:#16233A; --muted:#5B6980; --line:#C9D3E0;
  --accent:#E8681C; --accent-ink:#FFFFFF; --hit:#2E8B57; --miss:#C0392B; --hit-bg:#E3F3EA; --miss-bg:#FBE6E3;
  --ad:#DCE4EE; --track:#D3DCE7;
}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){
  --bg:#101B2E; --paper:#18253C; --grid:rgba(255,255,255,.06); --ink:#EEF3F8; --muted:#9AA9BF; --line:#2E3E5A;
  --accent:#F27C34; --accent-ink:#101B2E; --hit:#5CC98A; --miss:#F07A6B; --hit-bg:#1B3A2C; --miss-bg:#43231F;
  --ad:#22314A; --track:#2E3E5A;
}}
:root[data-theme="dark"]{
  --bg:#101B2E; --paper:#18253C; --grid:rgba(255,255,255,.06); --ink:#EEF3F8; --muted:#9AA9BF; --line:#2E3E5A;
  --accent:#F27C34; --accent-ink:#101B2E; --hit:#5CC98A; --miss:#F07A6B; --hit-bg:#1B3A2C; --miss-bg:#43231F;
  --ad:#22314A; --track:#2E3E5A;
}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);background-size:24px 24px;color:var(--ink);font:16px/1.5 "IBM Plex Sans",system-ui,sans-serif;padding-inline:16px;padding-block:20px 48px}
.wrap{max-width:560px;margin:0 auto;display:flex;flex-direction:column;gap:18px}
h1,h2,h3{font-family:"Bricolage Grotesque","IBM Plex Sans",sans-serif;text-wrap:balance;margin:0}
.mono{font-family:"IBM Plex Mono",ui-monospace,monospace;font-variant-numeric:tabular-nums}
header{display:flex;justify-content:space-between;align-items:baseline;gap:12px;flex-wrap:wrap}
header h1{font-size:34px;font-weight:800;letter-spacing:-.02em}
header h1 span{color:var(--accent)}
.meta{font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
.link{font:inherit;letter-spacing:inherit;text-transform:inherit;color:inherit;background:none;border:0;padding:0;text-decoration:underline;cursor:pointer}
.link:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.streak{font-weight:700;color:var(--ink);white-space:nowrap}
.streak.risk{color:var(--accent)}
.help h2{font-size:22px;font-weight:800;margin-bottom:8px}
.help ol{margin:0 0 10px;padding-left:20px;display:flex;flex-direction:column;gap:8px;font-size:15px}
.help .btn{margin-top:12px}
.card{background:var(--paper);border:1px solid var(--line);border-radius:6px;padding:20px}
.progress{display:flex;gap:6px}
.progress i{flex:1;height:6px;border-radius:3px;background:var(--track)}
.progress i.hit{background:var(--hit)} .progress i.miss{background:var(--miss)} .progress i.now{background:var(--accent)}
.q{font-size:24px;font-weight:800;line-height:1.2;margin-bottom:4px}
.unit{color:var(--muted);font-size:14px;margin-bottom:22px}
.slider{position:relative;height:56px;margin:6px 4px 0}
.slider .rail{position:absolute;left:0;right:0;top:22px;height:8px;border-radius:4px;background:var(--track)}
.slider .fill{position:absolute;top:22px;height:8px;background:var(--accent);border-radius:4px}
.slider input[type=range]{position:absolute;left:0;right:0;top:14px;width:100%;margin:0;height:24px;-webkit-appearance:none;appearance:none;background:none;pointer-events:none}
.slider input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;pointer-events:auto;width:26px;height:26px;border-radius:50%;background:var(--paper);border:3px solid var(--accent);box-shadow:0 1px 4px rgba(0,0,0,.25);cursor:grab}
.slider input[type=range]::-moz-range-thumb{pointer-events:auto;width:20px;height:20px;border-radius:50%;background:var(--paper);border:3px solid var(--accent);cursor:grab}
.slider input:focus-visible{outline:none}
.slider input:focus-visible::-webkit-slider-thumb{outline:3px solid var(--ink);outline-offset:2px}
.ticks{display:flex;justify-content:space-between;font-size:11px;color:var(--muted);margin:0 4px}
.bounds{display:grid;grid-template-columns:1fr auto 1fr;gap:10px;align-items:center;margin-top:10px}
.bounds label{display:flex;flex-direction:column;gap:4px;font-size:11px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
.bounds input{font:700 20px/1.2 "IBM Plex Mono",monospace;padding:8px 10px;border:1px solid var(--line);border-radius:4px;background:var(--bg);color:var(--ink);width:100%;min-width:0}
.bounds input:focus-visible{outline:2px solid var(--accent);outline-offset:1px}
.bounds .to{color:var(--muted);padding-top:18px}
.tight{display:flex;justify-content:space-between;font-size:13px;color:var(--muted);margin-top:12px}
.tight b{color:var(--ink)}
.btn{font:600 16px "IBM Plex Sans",sans-serif;background:var(--accent);color:var(--accent-ink);border:0;border-radius:6px;padding:14px 18px;width:100%;cursor:pointer;margin-top:16px}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--line)}
.btn:focus-visible{outline:3px solid var(--ink);outline-offset:2px}
.btn:disabled{opacity:.5;cursor:default}
.reveal{border-radius:6px;padding:16px;margin-top:16px;display:flex;flex-direction:column;gap:6px}
.reveal[hidden]{display:none} /* display:flex above would otherwise beat the hidden attribute */
.reveal.hit{background:var(--hit-bg)} .reveal.miss{background:var(--miss-bg)}
.reveal .big{font-size:30px;font-weight:700}
.reveal .pts{font-weight:800;font-family:"Bricolage Grotesque",sans-serif;font-size:20px}
.reveal.hit .pts{color:var(--hit)} .reveal.miss .pts{color:var(--miss)}
.fact{font-size:14px;color:var(--muted)}
.fact a{color:inherit;white-space:nowrap}
.ad{background:var(--ad);border:1px dashed var(--line);border-radius:4px;color:var(--muted);font-size:11px;text-transform:uppercase;letter-spacing:.08em;display:flex;align-items:center;justify-content:center;min-height:90px;text-align:center;padding:8px}
.ad{display:none} /* the three slots stay hidden until AdSense is approved: delete this line to show them */
.stats{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;text-align:center}
.stats div{background:var(--bg);border-radius:4px;padding:10px 6px}
.stats b{display:block;font-size:26px;font-weight:700}
.stats span{font-size:11px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
.challenge{margin:0;padding:14px 20px;font-weight:600;border-color:var(--accent)}
.remind{margin-top:16px;padding:14px;border:1px dashed var(--line);border-radius:6px;font-size:14px}
.remind p{margin:0}.remind .btn{margin-top:10px;padding:10px 14px;font-size:15px}
.rank{margin:12px 0 0;font-weight:600}
.share{font-size:18px;letter-spacing:.06em;margin:10px 0;line-height:1.7;white-space:pre-line}
.rows{display:flex;flex-direction:column;gap:8px;margin-top:14px}
.row{display:grid;grid-template-columns:24px 1fr auto;gap:10px;font-size:14px;align-items:baseline;border-top:1px solid var(--line);padding-top:8px}
.row .n{font-weight:700}
.row .pts{font-weight:700}
.row .r{color:var(--muted);font-size:12px}
.toast{position:fixed;left:50%;bottom:calc(20px + env(safe-area-inset-bottom,0px));transform:translateX(-50%);background:var(--ink);color:var(--bg);padding:10px 16px;border-radius:6px;font-size:14px;opacity:0;transition:opacity .2s}
.toast.on{opacity:1}
footer{font-size:12px;color:var(--muted);text-align:center}
footer nav{margin-top:10px;line-height:2}
footer a,.prose a,.ans a{color:inherit}
header h1 a{color:inherit;text-decoration:none}
.arow{display:grid;grid-template-columns:52px 1fr auto;gap:10px;align-items:center;width:100%;text-align:left;font:inherit;color:var(--ink);background:none;border:0;border-top:1px solid var(--line);padding:14px 0;cursor:pointer}
.arow:first-child{border-top:0}.arow .st{color:var(--muted);font-size:14px;text-align:right}
.arow:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.prose h2{font-size:24px;font-weight:800;margin:22px 0 8px}.prose h2:first-child{margin-top:0}
.prose p,.prose li{font-size:16px}.prose ul,.prose ol{padding-left:20px;display:flex;flex-direction:column;gap:6px}
.ans{border-top:1px solid var(--line);padding:16px 0}.ans:first-child{border-top:0;padding-top:0}
.ans h3{font-size:18px;font-weight:800;line-height:1.25}.ans .big{font-size:26px;font-weight:700;margin:6px 0}.ans .big small{font-size:14px;font-weight:400}
.ans p{margin:6px 0 0;font-size:14px;color:var(--muted)}.ans p.big{color:var(--ink)}
@media (prefers-reduced-motion:reduce){*{transition:none!important}}