:root{--ink:#0F172A;--ink2:#1E293B;--gold:#F59E0B;--gold2:#FCD34D;--emerald:#10B981;--emerald2:#059669;--cream:#fffaf0;--bg:#f6f7fb;--card:#fff;--line:#e3e6f0;--ok:#15803d;--okbg:#e8f7ee;--bad:#b91c1c;--badbg:#fdecec;--mute:#6b7190;--r:14px}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font:16px/1.55 system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;color:var(--ink);background:var(--bg);padding-bottom:calc(72px + env(safe-area-inset-bottom))}
a{color:#3b3fbf}
h1,h2,h3{line-height:1.25;margin:.2em 0 .5em}
h1{font-size:1.7rem}h2{font-size:1.25rem}h3{font-size:1.05rem}
.wrap{max-width:980px;margin:0 auto;padding:16px}
.top{position:sticky;top:0;z-index:20;background:var(--ink);color:#fff;display:flex;align-items:center;gap:14px;padding:10px 16px;padding-top:calc(10px + env(safe-area-inset-top))}
.brand{color:#fff;text-decoration:none;font-weight:800;font-size:1.15rem;letter-spacing:.2px}
.brand .hex{color:var(--gold)}
.topnav{display:none;margin-left:auto;gap:14px;align-items:center}
.topnav a{color:#d8dbf5;text-decoration:none;font-weight:600}
.topnav a:hover{color:#fff}
.chip{margin-left:auto;background:#1E293B;color:#fff;border-radius:99px;padding:4px 12px;text-decoration:none;font-weight:700;white-space:nowrap}
.chip.stars{color:var(--gold2)}
.chip .streak{color:#ffb4a2;margin-left:6px}
.btn{display:inline-block;background:var(--gold);color:#241a00;border:0;border-radius:12px;padding:12px 18px;font:inherit;font-weight:800;text-decoration:none;cursor:pointer;text-align:center}
.btn:hover{filter:brightness(.96)}
.btn.ghost{background:#fff;color:var(--ink);border:2px solid var(--line)}
.btn.dark{background:var(--ink);color:#fff}
.btn.small{padding:6px 12px;border-radius:10px}
.btn.block{display:block;width:100%}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:16px;margin:12px 0;box-shadow:0 1px 2px rgba(20,24,60,.04)}
.card.hero{background:linear-gradient(135deg,#0F172A,#1E293B 60%,#064E3B);color:#fff;border:0}
.card.hero a.btn{margin-top:6px}
.grid{display:grid;gap:12px}
.grid.two{grid-template-columns:repeat(auto-fit,minmax(260px,1fr))}
.grid.three{grid-template-columns:repeat(auto-fit,minmax(200px,1fr))}
.subj{display:flex;gap:12px;align-items:center;text-decoration:none;color:inherit}
.subj .em{font-size:2rem;width:56px;height:56px;border-radius:14px;background:var(--cream);display:grid;place-items:center;flex:none}
.subj b{display:block;font-size:1.05rem}
.mute{color:var(--mute)}
.small{font-size:.9rem}
.msgs{margin-bottom:8px}
.msg{padding:10px 14px;border-radius:10px;margin:6px 0;background:#eef0ff;border:1px solid #d5d9ff}
.msg.success{background:var(--okbg);border-color:#bfe8cd}
.msg.error{background:var(--badbg);border-color:#f3c3c3}
form .row{margin:12px 0}
label{display:block;font-weight:700;margin-bottom:4px}
input[type=text],input[type=email],input[type=password],input[type=number],select{width:100%;padding:12px;border:2px solid var(--line);border-radius:10px;font:inherit;background:#fff}
input:focus,select:focus{outline:3px solid #cfd4ff;border-color:#10B981}
.errorlist{list-style:none;margin:4px 0;padding:0;color:var(--bad);font-weight:600}
.pills{display:flex;flex-wrap:wrap;gap:8px}
.pill{display:inline-flex;align-items:center;gap:6px;border:2px solid var(--line);background:#fff;border-radius:99px;padding:8px 14px;font-weight:700;cursor:pointer;color:var(--ink);text-decoration:none}
.pill:hover{border-color:#10B981}
.pill small{color:var(--mute);font-weight:600}
.pill.on{background:var(--ink);color:#fff;border-color:var(--ink)}
.bar{height:10px;background:#e8eaf7;border-radius:99px;overflow:hidden}
.bar i{display:block;height:100%;background:linear-gradient(90deg,var(--gold),#ffcf4d);border-radius:99px}
.tabs{display:flex;gap:6px;overflow-x:auto;margin:10px 0 4px;padding-bottom:4px}
.tabs button{border:0;background:#E2E8F0;border-radius:10px;padding:8px 14px;font-weight:700;color:var(--ink2);white-space:nowrap;cursor:pointer}
.tabs button.on{background:var(--ink);color:#fff}
details.sec{background:#fff;border:1px solid var(--line);border-radius:var(--r);margin:10px 0;overflow:hidden}
details.sec>summary{padding:14px 16px;font-weight:800;cursor:pointer;list-style:none;display:flex;justify-content:space-between;gap:10px}
details.sec>summary::-webkit-details-marker{display:none}
details.sec .inner{padding:0 12px 12px}
.topic{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:10px 6px;border-top:1px solid var(--line)}
.topic form{margin:0}
.acc{font-weight:800}
.acc.hi{color:var(--ok)}.acc.lo{color:var(--bad)}
.tabbar{position:fixed;left:0;right:0;bottom:0;background:#fff;border-top:1px solid var(--line);display:flex;justify-content:space-around;padding:6px 4px calc(6px + env(safe-area-inset-bottom));z-index:30}
.tabbar a{flex:1;text-align:center;text-decoration:none;color:var(--mute);font-size:.72rem;font-weight:700}
.tabbar a span{display:block;font-size:1.35rem}
.tabbar a.on{color:var(--ink)}
.foot{text-align:center;color:var(--mute);font-size:.85rem;padding:12px}
.foot a{color:var(--mute)}
/* player */
.player{max-width:820px;margin:0 auto}
.phead{display:flex;align-items:center;gap:10px;justify-content:space-between;margin-bottom:8px}
.timer{font-variant-numeric:tabular-nums;font-weight:800;background:var(--ink);color:#fff;border-radius:10px;padding:6px 12px}
.timer.warn{background:var(--bad)}
.qcard{background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:16px}
.qmeta{display:flex;justify-content:space-between;color:var(--mute);font-size:.88rem;font-weight:600;margin-bottom:8px;gap:8px;flex-wrap:wrap}
.instr{background:var(--cream);border-left:4px solid var(--gold);padding:8px 12px;border-radius:8px;margin-bottom:10px;font-size:.95rem}
.passage{background:#f2f4fb;padding:10px 12px;border-radius:8px;margin-bottom:10px;white-space:pre-wrap;font-size:.95rem;max-height:260px;overflow:auto}
.stem{font-size:1.1rem;font-weight:600;white-space:pre-wrap;margin:6px 0 12px}
.stem em,.opt em,.instr em{font-style:normal;text-decoration:underline;text-decoration-thickness:2px;text-underline-offset:3px;font-weight:800}
.diagram{max-width:100%;max-height:340px;display:block;margin:6px auto 12px;background:#fff;border:1px solid var(--line);border-radius:10px;padding:6px}
.opts{display:grid;gap:8px}
.opt{display:flex;gap:12px;align-items:flex-start;width:100%;text-align:left;border:2px solid var(--line);background:#fff;border-radius:12px;padding:12px;font:inherit;cursor:pointer;color:var(--ink)}
.opt:hover:not([disabled]){border-color:#10B981;background:#fafaff}
.opt .l{flex:none;width:30px;height:30px;border-radius:50%;background:#eef0ff;display:grid;place-items:center;font-weight:800}
.opt.sel{border-color:var(--ink);background:#f0f1ff}
.opt.sel .l{background:var(--ink);color:#fff}
.opt.good{border-color:var(--ok);background:var(--okbg)}
.opt.good .l{background:var(--ok);color:#fff}
.opt.bad{border-color:var(--bad);background:var(--badbg)}
.opt.bad .l{background:var(--bad);color:#fff}
.opt[disabled]{cursor:default}
.fb{margin-top:12px;border-radius:12px;padding:12px 14px}
.fb.ok{background:var(--okbg);border:1px solid #bfe8cd}
.fb.no{background:var(--badbg);border:1px solid #f3c3c3}
.fb .also{margin-top:8px;font-size:.88rem;color:var(--ink2);font-weight:600}
.pnav{display:flex;gap:8px;justify-content:space-between;margin:12px 0}
.palette{display:grid;grid-template-columns:repeat(auto-fill,minmax(40px,1fr));gap:6px;margin-top:10px}
.palette button{height:40px;border-radius:8px;border:2px solid var(--line);background:#fff;font-weight:700;cursor:pointer}
.palette button.ans{background:var(--ink);color:#fff;border-color:var(--ink)}
.palette button.flag{border-color:var(--gold);box-shadow:inset 0 0 0 2px var(--gold)}
.palette button.cur{outline:3px solid #10B981}
.progressline{display:flex;align-items:center;gap:8px;margin-bottom:8px}
.progressline .bar{flex:1}
.score{font-size:3rem;font-weight:900;line-height:1}
.badge{display:flex;gap:10px;align-items:center;padding:10px;border-radius:12px;border:1px solid var(--line);background:#fff}
.badge .ic{font-size:2rem}
.badge.locked{opacity:.45;filter:grayscale(1)}
.rev{border-top:1px solid var(--line);padding:12px 0}
.rev .tag{display:inline-block;border-radius:6px;padding:1px 8px;font-size:.8rem;font-weight:800}
.tag.ok{background:var(--okbg);color:var(--ok)}.tag.no{background:var(--badbg);color:var(--bad)}.tag.skip{background:#eee;color:#555}
.modal{position:fixed;inset:0;background:rgba(20,24,60,.55);display:none;align-items:center;justify-content:center;z-index:50;padding:16px}
.modal.on{display:flex}
.modal .box{background:#fff;border-radius:16px;padding:20px;max-width:420px;width:100%}
.price{font-size:2rem;font-weight:900}
.price small{font-size:.9rem;font-weight:600;color:var(--mute)}
.lesson h2{margin-top:1.4em}
.lesson table{border-collapse:collapse;width:100%;margin:10px 0}
.lesson th,.lesson td{border:1px solid var(--line);padding:6px 8px;text-align:left}
.lesson th{background:var(--cream)}
.kp{background:var(--cream);border-left:4px solid var(--gold);padding:10px 14px;border-radius:8px}
@media(min-width:760px){
  .topnav{display:flex}.chip{margin-left:0}.tabbar{display:none}body{padding-bottom:0}
  h1{font-size:2.1rem}
}
body.focus{padding-bottom:20px}
.pnav .btn{padding:10px 12px;white-space:nowrap}
.stem,.opt>span:last-child,.fb{overflow-x:auto;max-width:100%}
.opt>span:last-child{min-width:0}
/* school reports */
.tscroll{overflow-x:auto;-webkit-overflow-scrolling:touch;border:1px solid var(--line);border-radius:var(--r);background:#fff}
.rtable{border-collapse:collapse;width:100%;font-size:.9rem;min-width:720px}
.rtable th{background:var(--ink);color:#fff;text-align:left;padding:8px;font-size:.8rem;position:sticky;top:0;white-space:nowrap}
.rtable td{padding:8px;border-top:1px solid var(--line);vertical-align:top}
.rtable td.num,.rtable th.num{text-align:right;font-variant-numeric:tabular-nums}
.rtable tr:nth-child(even) td{background:#F8FAFC}
.tiles{display:grid;grid-template-columns:repeat(auto-fit,minmax(130px,1fr));gap:10px;margin:12px 0}
.tile{background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:12px}
.tile b{display:block;font-size:1.5rem;line-height:1.2}
.tile span{color:var(--mute);font-size:.82rem}
.tag{display:inline-block;border-radius:99px;padding:2px 10px;font-size:.78rem;font-weight:700;background:#E2E8F0;white-space:nowrap}
.tag.Strong{background:var(--okbg);color:var(--ok)}.tag.Needs{background:var(--badbg);color:var(--bad)}
.tag.Practise{background:#fff1cc;color:#7a5600}.tag.No{background:#eee;color:#555}
body.wide .wrap{max-width:1360px}
.rtable td.nowrap{white-space:nowrap}
.rtable td.topics{min-width:220px;font-size:.82rem}

/* brand */
.brand img.logo{height:34px;width:auto;display:block}
.brand .school{display:flex;align-items:center;gap:8px;color:#fff;font-weight:800;text-decoration:none}
.brand .school img{height:34px;width:34px;object-fit:contain;background:#fff;border-radius:8px;padding:2px}
.powered{display:inline-block;vertical-align:middle}
.powered img{height:28px;width:auto;display:block}
.foot .support{display:block;margin:6px 0 2px;font-size:.8rem}
body.focus .qwm{position:fixed;inset:0;pointer-events:none;z-index:0;background-repeat:no-repeat;background-position:center 55%;background-size:min(60vw,360px);opacity:.05}
body.focus .powered-fixed{position:fixed;right:10px;bottom:calc(8px + env(safe-area-inset-bottom));z-index:3;opacity:.92}
body.focus .powered-fixed img{height:22px}
body.focus main{position:relative;z-index:1}
/* recap vault */
.vfilters{display:grid;gap:8px}
@media (min-width:760px){.vfilters{position:sticky;top:56px;z-index:6}}
.vfilters input[type=search]{width:100%;padding:12px;border:2px solid var(--line);border-radius:10px;font:inherit}
.vrow{flex-wrap:nowrap;overflow-x:auto;-webkit-overflow-scrolling:touch;padding-bottom:2px}
.vrow .pill{white-space:nowrap;padding:6px 12px;font-size:.88rem}
.vtools{display:flex;justify-content:space-between;align-items:center;gap:8px;flex-wrap:wrap}
.vcard{background:#fff;border:1px solid var(--line);border-radius:var(--r);margin:10px 0;overflow:hidden}
.vcard summary{cursor:pointer;padding:12px 14px;list-style:none;display:block}
.vcard summary::-webkit-details-marker{display:none}
.vcard[open] summary{border-bottom:1px solid var(--line);background:#F8FAFC}
.vtitle{display:inline;font-size:1rem}
.vmeta{display:block;color:var(--mute);font-size:.8rem;margin-top:3px}
.vtag{display:inline-block;border-radius:6px;padding:1px 8px;font-size:.72rem;font-weight:800;margin-right:6px;vertical-align:2px;color:#fff}
.vtag.formula{background:var(--emerald2)}.vtag.law{background:#B45309}.vtag.si{background:#1D4ED8}
.vbody{padding:12px 14px}
.vstmt{margin:0 0 10px}
.vtex{overflow-x:auto;overflow-y:hidden;padding:6px 2px;margin:4px 0 10px;background:#F8FAFC;border-radius:10px;font-size:.95rem}
.vvars{margin:0 0 10px;padding-left:18px;font-size:.9rem}
.vvars li{margin:2px 0}
.vtrap{background:#FFFBEB;border-left:4px solid var(--gold);border-radius:8px;padding:8px 10px;font-size:.92rem}
.vtex .texline .katex-display{margin:.35em 0}
.vtex .texline{overflow-x:auto;overflow-y:hidden}
@media (max-width:520px){.vtex{font-size:.88rem}}