:root{
  --teal:#0E5A66; --teal-d:#083a42; --teal-l:#E8F2F3;
  --orange:#B4430F; --orange-l:#FBEDE6;
  --green:#1B6E3A; --green-l:#E6F4EA;
  --red:#A61B1B; --red-l:#FBEAEA;
  --ink:#161616; --muted:#5a5a5a; --line:#d6dfe0; --bg:#F6F8F8;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Inter,Roboto,sans-serif;font-size:17px;line-height:1.5}
sup,sub{font-size:.7em;line-height:0}
button{font:inherit;color:inherit;cursor:pointer}
.top{position:sticky;top:0;z-index:5;display:flex;justify-content:space-between;align-items:center;padding:10px 16px;padding-top:max(10px,env(safe-area-inset-top));background:var(--teal);color:#fff}
.linkbtn{display:flex;align-items:center;gap:8px;background:none;border:0;color:#fff;font-weight:700;min-height:44px;padding:0 4px}
.pill{background:#fff;color:var(--teal);border:0;border-radius:999px;padding:8px 16px;font-weight:700;min-height:40px}
main{max-width:720px;margin:0 auto;padding:18px 16px 60px}
h1{font-size:28px;line-height:1.2;margin:6px 0 4px;color:var(--teal-d)}
h2{font-size:20px;margin:0}
.sub{color:var(--muted);margin:0 0 18px}
.card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px;margin-bottom:12px}
.secbtn{display:block;width:100%;text-align:left;background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 16px;margin-bottom:10px;min-height:64px}
.secbtn:hover,.secbtn:focus-visible{border-color:var(--teal);outline:none;box-shadow:0 0 0 3px var(--teal-l)}
.secbtn .row{display:flex;justify-content:space-between;align-items:baseline;gap:10px}
.secbtn .name{font-weight:800;font-size:18px;color:var(--teal-d)}
.secbtn .meta{font-size:14px;color:var(--muted)}
.secbtn .blurb{font-size:14px;color:var(--muted)}
.bar{height:8px;background:var(--teal-l);border-radius:99px;overflow:hidden;margin-top:8px}
.bar>span{display:block;height:100%;background:var(--teal)}
.resume{background:var(--teal);color:#fff;border:0}
.resume .name,.resume .meta,.resume .blurb{color:#fff}
.actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:14px}
.btn{border:0;border-radius:12px;padding:12px 20px;font-weight:700;min-height:48px;background:var(--teal);color:#fff}
.btn:disabled{opacity:.4;cursor:not-allowed}
.btn.ghost{background:#fff;color:var(--teal);border:1.5px solid var(--teal)}
.btn.warn{background:#fff;color:var(--red);border:1.5px solid var(--red)}
.btn.orange{background:var(--orange)}
.qhead{display:flex;justify-content:space-between;align-items:center;gap:10px;font-size:14px;color:var(--muted);margin-bottom:6px}
.badge{display:inline-block;font-size:13px;font-weight:800;letter-spacing:.3px;padding:3px 10px;border-radius:999px;background:var(--teal-l);color:var(--teal-d)}
.badge.prac{background:var(--orange-l);color:var(--orange)}
.prompt{font-size:19px;margin:12px 0 16px}
.choices{display:flex;flex-direction:column;gap:10px}
.choice{display:flex;align-items:center;gap:12px;text-align:left;background:#fff;border:1.5px solid var(--line);border-radius:12px;padding:12px 14px;min-height:52px;width:100%}
.choice .dot{flex:none;width:22px;height:22px;border-radius:50%;border:2px solid #9aa9ab}
.choice.sel{border-color:var(--teal);background:var(--teal-l)}
.choice.sel .dot{border-color:var(--teal);background:radial-gradient(var(--teal) 45%,transparent 50%)}
.choice.right{border-color:var(--green);background:var(--green-l)}
.choice.wrong{border-color:var(--red);background:var(--red-l)}
.choice:disabled{cursor:default;color:var(--ink)}
.orb{display:flex;flex-wrap:wrap;gap:10px 14px;align-items:flex-end}
.orb .sl{display:flex;flex-direction:column;align-items:center}
.orb .boxes{display:flex}
.orb .box{width:30px;height:30px;border:1.5px solid var(--ink);display:flex;align-items:center;justify-content:center;font-size:17px;font-weight:700;background:#fff;letter-spacing:-2px}
.orb .box+.box{border-left:0}
.orb .lbl{font-size:13px;color:var(--muted);margin-top:2px}
.num{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:20px}
.num input{font:inherit;width:120px;padding:10px 12px;border:1.5px solid var(--line);border-radius:10px;min-height:48px}
.num input.exp{width:80px}
.num .pm{min-width:48px;min-height:48px;border-radius:10px;border:1.5px solid var(--line);background:#fff;font-weight:800}
.num label{position:absolute;left:-9999px}
.hint{font-size:14px;color:var(--muted);margin-top:8px}
.strip{min-height:58px;display:flex;flex-wrap:wrap;gap:8px;padding:10px;border:1.5px dashed #9aa9ab;border-radius:12px;background:#fff;margin-bottom:12px}
.strip.empty::before{content:"Tap tiles below to build your answer";color:var(--muted);font-size:15px;align-self:center}
.tiles{display:flex;flex-wrap:wrap;gap:8px}
.tile{border:1.5px solid var(--teal);background:var(--teal-l);color:var(--teal-d);border-radius:10px;padding:8px 12px;min-height:44px;min-width:48px;font-weight:700;font-size:17px}
.tile.used{visibility:hidden}
.strip .tile{background:var(--teal);color:#fff}
.small{font-size:14px}
.fb{border-radius:14px;padding:14px 16px;margin-top:16px}
.fb.ok{background:var(--green-l);border:1.5px solid var(--green)}
.fb.no{background:var(--red-l);border:1.5px solid var(--red)}
.fb h3{margin:0 0 6px;font-size:18px}
.fb.ok h3{color:var(--green)} .fb.no h3{color:var(--red)}
.fb p{margin:4px 0}
.lesson{background:#fff;border:1.5px solid var(--teal);border-left-width:1.5px;border-radius:14px;padding:14px 16px;margin-top:14px}
.lesson h3{margin:0 0 8px;color:var(--teal);font-size:18px}
.lesson p{margin:6px 0} .lesson ul,.lesson ol{margin:6px 0;padding-left:22px}
.lesson .orb{margin:10px 0}
table.mini{border-collapse:collapse;margin:8px 0;font-size:15px}
table.mini th,table.mini td{border:1px solid #9fb8bc;padding:3px 8px;text-align:center}
table.mini th{background:var(--teal-l);text-align:left}
.score{font-size:44px;font-weight:800;color:var(--teal-d);line-height:1}
.missed li{margin:6px 0}
.tag{font-size:12px;font-weight:800;padding:2px 8px;border-radius:999px;margin-left:6px}
.tag.no{background:var(--red-l);color:var(--red)} .tag.ok{background:var(--green-l);color:var(--green)}
dialog{border:0;border-radius:16px;padding:0;width:min(720px,94vw);max-height:88vh}
dialog::backdrop{background:rgba(0,0,0,.45)}
.sheet-head{position:sticky;top:0;display:flex;justify-content:space-between;align-items:center;padding:12px 16px;background:var(--teal);color:#fff}
.sheet-body{padding:6px 18px 20px;font-size:15px;overflow:auto}
.sheet-body h3{color:#fff;background:var(--teal);padding:2px 10px;font-size:15px;margin:16px 0 6px}
.sheet-body p{margin:6px 0}
.formulas{display:flex;gap:18px;flex-wrap:wrap;font-weight:800;color:var(--teal);font-size:18px;border:1.5px solid var(--teal);padding:6px 12px;border-radius:10px}
:focus-visible{outline:3px solid var(--orange);outline-offset:2px}
@media (max-width:420px){.prompt{font-size:18px}.orb .box{width:26px;height:26px;font-size:15px}}