:root{--bg:#0b1626;--panel:#13263c;--ink:#e8eef5;--mute:#9fb3c8;--minus:#4cc9f0;--plus:#ffb347;--ok:#6fdc8c;--bad:#ff7b7b;--line:#2a4560}
@media (prefers-color-scheme:light){:root{--bg:#eef3f8;--panel:#fff;--ink:#12263a;--mute:#4d6379;--line:#c5d3e0;--minus:#0a78a8;--plus:#b86400;--ok:#13813a;--bad:#c0392b}}
*{box-sizing:border-box}
html,body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;padding:env(safe-area-inset-top) 0 0}
h1,h2,h3{font-family:Georgia,"Iowan Old Style",serif;line-height:1.2;margin:.2em 0}
header{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:10px 16px;border-bottom:1px solid var(--line);flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--ink);font-weight:700}
.brand img{height:36px;width:auto}
.home{color:var(--ink);border:1px solid var(--line);padding:8px 14px;border-radius:8px;text-decoration:none;min-height:40px;display:inline-flex;align-items:center}
main{max-width:920px;margin:0 auto;padding:16px}
section.screen{display:none}section.screen.on{display:block}
.card{background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:16px;margin:12px 0}
img.cover{width:100%;height:auto;border-radius:12px;display:block}
button{font:inherit;color:var(--ink);background:var(--panel);border:2px solid var(--line);border-radius:10px;padding:10px 16px;min-height:48px;cursor:pointer;touch-action:manipulation}
button:hover{border-color:var(--minus)}button:focus-visible,a:focus-visible{outline:3px solid var(--plus);outline-offset:2px}
button.primary{background:var(--plus);color:#1a1200;border-color:var(--plus);font-weight:700}
.row{display:flex;gap:10px;flex-wrap:wrap}.row>*{flex:1 1 140px}
canvas{width:100%;height:230px;display:block;background:var(--panel);border:1px solid var(--line);border-radius:12px;touch-action:none}
.meter{height:14px;background:var(--line);border-radius:8px;overflow:hidden}.meter i{display:block;height:100%;width:100%;background:var(--ok);transition:width .1s}
.hud{display:flex;justify-content:space-between;gap:8px;flex-wrap:wrap;font-size:14px;color:var(--mute)}
#msg{min-height:3em;margin:8px 0}.good{color:var(--ok)}.warn{color:var(--bad)}
.note{font-size:14px;color:var(--mute);border-left:3px solid var(--plus);padding-left:10px}
.step{font-size:20px;font-weight:700}
.opt{display:block;width:100%;text-align:left;margin:8px 0}
.legend span{display:inline-block;margin-right:14px}
footer{margin-top:32px;border-top:1px solid var(--line);padding:20px 16px calc(20px + env(safe-area-inset-bottom));text-align:center;color:var(--mute);font-size:14px}
@media (max-width:520px){h1{font-size:1.6rem}.step{font-size:18px}}

.toolbar{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-bottom:16px}.toolbar #clock{font-size:24px;font-weight:700;margin-right:auto;font-variant-numeric:tabular-nums}.toolbar button{padding:8px 12px}dialog{width:min(650px,calc(100% - 24px));max-height:85dvh;overflow:auto;color:var(--ink);background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:24px}dialog::backdrop{background:#061323cc}dialog li{margin-bottom:12px}.about,footer.wrap{width:min(920px,calc(100% - 32px));margin:24px auto;padding:24px 16px;background:#f5f2e9;color:#273d35;border-radius:16px;display:flex;align-items:center;gap:22px;flex-wrap:wrap}.about p{flex:1;min-width:180px;line-height:1.6;font-size:14px;margin:0}.about-star{font-size:36px;color:#df592f}.device-note{font-size:11px;line-height:1.8}footer.wrap{font-size:13px;text-align:left}footer a{color:inherit}.footer-meta{margin-left:auto;font-size:12px;overflow-wrap:anywhere}header img{max-width:100%}#lesson-list button{flex:1 1 220px}body.is-paused #play,body.is-paused #quiz{opacity:.65}button:disabled{opacity:.6;cursor:default}@media(max-width:520px){main{padding:12px}header{padding:10px 12px}.row>*{flex-basis:120px}.about p br{display:none}.footer-meta{width:100%;margin-left:0}canvas{height:250px}.toolbar button{font-size:14px}}@media(prefers-reduced-motion:reduce){*{transition:none!important}}