:root{--bg:#f4f6fb;--card:#fff;--ink:#14213d;--mut:#5b6785;--pri:#1d4ed8;--ok:#0f9d58;--bad:#d93025;--line:#dde3f0;--easy:#0f9d58;--medium:#e8a200;--complex:#e8590c;--tough:#c2255c}
@media(prefers-color-scheme:dark){:root{--bg:#0f1526;--card:#182038;--ink:#e8ecf8;--mut:#9aa6c6;--line:#2a3558;--pri:#6f9bff}}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,"Noto Sans","Noto Sans Devanagari","Noto Sans Bengali","Noto Sans Tamil","Noto Sans Telugu","Noto Sans Kannada","Noto Sans Malayalam","Noto Sans Gujarati","Noto Sans Gurmukhi","Noto Sans Oriya","Noto Nastaliq Urdu",sans-serif}
.top{display:flex;justify-content:space-between;align-items:center;padding:12px 16px;background:var(--pri);color:#fff;position:sticky;top:0;z-index:5}.logo span{opacity:.8;font-weight:500}
.top button{background:rgba(255,255,255,.18);color:#fff;border:0;border-radius:8px;padding:6px 12px;font:inherit;cursor:pointer}
main{max-width:720px;margin:0 auto;padding:16px}
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px;margin:0 0 12px}
h1{font-size:22px;margin:4px 0 4px}h2{font-size:18px;margin:0 0 8px}.mut{color:var(--mut);font-size:14px}
label{display:block;font-weight:600;margin:12px 0 4px;font-size:14px}
input,select{width:100%;padding:11px 12px;border:1px solid var(--line);border-radius:10px;font:inherit;background:var(--bg);color:var(--ink)}
.row{display:flex;gap:10px}.row>*{flex:1}
.btn{display:block;width:100%;margin-top:16px;padding:12px;border:0;border-radius:10px;background:var(--pri);color:#fff;font:inherit;font-weight:700;cursor:pointer}.btn.alt{background:transparent;color:var(--pri);border:1px solid var(--pri)}.btn:disabled{opacity:.5}
.link{background:none;border:0;color:var(--pri);font:inherit;cursor:pointer;margin-top:14px;padding:0;text-decoration:underline}
.err{color:var(--bad);margin-top:10px;font-size:14px}
.day{display:flex;justify-content:space-between;align-items:center;gap:10px;cursor:default}.day .st{font-size:13px;color:var(--mut)}
.pill{display:inline-block;padding:2px 9px;border-radius:99px;font-size:12px;font-weight:700;color:#fff}.pill.easy{background:var(--easy)}.pill.medium{background:var(--medium)}.pill.complex{background:var(--complex)}.pill.tough{background:var(--tough)}
.sub{font-size:13px;font-weight:700;color:var(--pri);text-transform:uppercase;letter-spacing:.04em;margin:18px 0 6px}
.q{border-top:1px solid var(--line);padding:14px 0}.q:first-of-type{border-top:0}.q p{margin:8px 0}.opt{display:flex;gap:8px;align-items:flex-start;padding:7px 8px;border-radius:8px;cursor:pointer}.opt input{width:auto;margin-top:5px}
.res{font-weight:700;font-size:14px;margin-top:6px}.res.ok{color:var(--ok)}.res.no{color:var(--bad)}
.sol{background:var(--bg);border-radius:10px;padding:10px;margin-top:8px;font-size:14px}
.small{font-size:13px;color:var(--mut)}.small .btn{display:inline-block;width:auto;margin:0 8px 0 0;padding:5px 12px;font-size:13px}
[dir=rtl] .row{flex-direction:row-reverse}