:root{
  --bg:#0f1730; --card:#18233f; --card2:#1f2c4d; --line:#2d3c63; --ink:#eef2ff; --mute:#a9b4d6;
  --easy:#22c55e; --med:#3b82f6; --hard:#f59e0b; --exp:#ef4444; --gold:#fbbf24; --ok:#22c55e; --bad:#f87171;
}
*{box-sizing:border-box}
html,body{margin:0;background:var(--bg);color:var(--ink)}
body{font-family:Nunito,system-ui,sans-serif;font-weight:700;font-size:17px;line-height:1.45}
.page{max-width:820px;margin:0 auto;padding:16px 16px 40px}
.credit{color:var(--mute);font-size:13px;text-align:center;margin-top:28px}
h1,h2,h3,.fd{font-family:Fredoka,Nunito,sans-serif;font-weight:700;margin:0}
button{font:inherit;cursor:pointer}
.hide{display:none!important}

/* ------------------------------------------------------------ menu */
.hero{background:linear-gradient(135deg,#1e3a8a,#6d28d9);border-radius:22px;padding:22px 22px 20px;margin-bottom:18px;position:relative;overflow:hidden}
.hero h1{font-size:30px}
.hero p{margin:6px 0 0;color:#dbe4ff}
.hero .goal{display:inline-block;margin-top:12px;background:rgba(0,0,0,.25);border-radius:999px;padding:6px 14px;font-size:15px}
.hero .big{position:absolute;right:14px;top:6px;font-size:64px;opacity:.25}

.ladder{display:grid;gap:12px;margin-bottom:22px}
.lvl{display:flex;align-items:center;gap:14px;background:var(--card);border:3px solid var(--line);border-radius:18px;padding:14px 16px;text-align:left;color:var(--ink);width:100%}
.lvl .ic{font-size:34px;width:52px;height:52px;border-radius:14px;display:grid;place-items:center;flex:none;background:rgba(255,255,255,.08)}
.lvl .tx{flex:1;min-width:0}
.lvl .nm{font-family:Fredoka;font-size:22px}
.lvl .ds{color:var(--mute);font-size:14.5px}
.lvl .st{font-size:22px;letter-spacing:2px;flex:none;text-align:right}
.lvl .st small{display:block;font-size:12.5px;letter-spacing:0;color:var(--mute)}
.lvl.easy{border-color:var(--easy)} .lvl.easy .ic{background:rgba(34,197,94,.18)}
.lvl.med{border-color:var(--med)}  .lvl.med .ic{background:rgba(59,130,246,.18)}
.lvl.hard{border-color:var(--hard)} .lvl.hard .ic{background:rgba(245,158,11,.18)}
.lvl.exp{border-color:var(--exp)}  .lvl.exp .ic{background:rgba(239,68,68,.18)}
.lvl.locked{border-color:var(--line);opacity:.6;cursor:not-allowed}
.lvl:not(.locked):hover{transform:translateY(-2px);transition:transform .15s}
.lvl.next{box-shadow:0 0 0 4px rgba(251,191,36,.35);animation:pulse 1.8s infinite}
@keyframes pulse{50%{box-shadow:0 0 0 8px rgba(251,191,36,.12)}}

.sec-h{display:flex;align-items:baseline;gap:10px;margin:24px 0 10px}
.sec-h h2{font-size:22px}
.sec-h span{color:var(--mute);font-size:14.5px}
.fix{display:flex;gap:14px;align-items:center;background:linear-gradient(135deg,#7c2d12,#9a3412);border-radius:18px;padding:14px 16px;width:100%;border:0;color:#fff;text-align:left}
.fix .ic{font-size:34px}
.fix b{font-family:Fredoka;font-size:20px;display:block}
.fix span{color:#fed7aa;font-size:14.5px}

.tricks{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:10px}
.tk{background:var(--card);border:2px solid var(--line);border-radius:14px;padding:12px 13px;color:var(--ink);text-align:left}
.tk b{display:block;font-family:Fredoka;font-size:17px}
.tk span{color:var(--mute);font-size:14px}
.tk.weak{border-color:#f97316}
.tk.weak b::after{content:' · practice me';color:#fb923c;font-size:13px;font-family:Nunito}

/* ------------------------------------------------------------ learn sheet */
.sheet{background:var(--card);border-radius:20px;padding:20px;border:2px solid var(--line)}
.sheet h2{font-size:26px;margin-bottom:6px}
.sheet .how{margin:10px 0}
.sheet .how li{margin:4px 0}
.trick{background:rgba(251,191,36,.12);border:2px dashed var(--gold);border-radius:14px;padding:10px 13px;margin:12px 0;color:#fde68a}
.trick::before{content:'💡 Trick: ';font-weight:900;color:var(--gold)}
.ex{background:#0c1328;border-radius:14px;padding:12px 14px;margin:10px 0}
.ex .q{color:var(--mute);font-size:14.5px}
.warn{background:rgba(248,113,113,.12);border-left:5px solid var(--bad);border-radius:10px;padding:9px 12px;margin:10px 0;color:#fecaca}
.warn::before{content:'⚠️ Watch out: ';font-weight:900}

/* ------------------------------------------------------------ buttons */
.btn{border:0;border-radius:14px;padding:13px 20px;font-weight:900;font-size:17px;color:#fff;background:#4f46e5;box-shadow:0 4px 0 #3730a3}
.btn:active{transform:translateY(2px);box-shadow:0 2px 0 #3730a3}
.btn.go{background:#16a34a;box-shadow:0 4px 0 #15803d}
.btn.ghost{background:transparent;border:2px solid var(--line);box-shadow:none;color:var(--ink)}
.btn.gold{background:#d97706;box-shadow:0 4px 0 #92400e}
.btn:disabled{opacity:.45}
.row{display:flex;flex-wrap:wrap;gap:10px;align-items:center}
.back{background:none;border:0;color:var(--mute);font-weight:800;padding:4px 0;margin-bottom:10px}

/* ------------------------------------------------------------ quiz */
.qtop{display:flex;align-items:center;gap:10px;margin-bottom:8px;flex-wrap:wrap}
.qtop .lv{font-family:Fredoka;font-size:18px;padding:4px 12px;border-radius:999px;background:var(--card2)}
.qtop .lv.easy{background:var(--easy);color:#052e12}.qtop .lv.med{background:var(--med)}.qtop .lv.hard{background:var(--hard);color:#3b2300}.qtop .lv.exp{background:var(--exp)}
.qtop .gap{flex:1}
.qtop .sc{color:var(--mute);font-size:15px}
.streak{color:#fb923c;font-weight:900}
.bar{height:10px;border-radius:99px;background:var(--card2);overflow:hidden;margin-bottom:14px}
.bar i{display:block;height:100%;background:linear-gradient(90deg,#22c55e,#a3e635);transition:width .3s}
.qcard{background:var(--card);border:2px solid var(--line);border-radius:20px;padding:20px}
.chip{display:inline-block;font-size:13px;font-weight:900;text-transform:uppercase;letter-spacing:.06em;color:#c7d2fe;background:rgba(99,102,241,.2);border-radius:99px;padding:3px 10px;margin-bottom:10px}
.prompt{font-size:21px;line-height:1.5}
.prompt .num{font-family:Fredoka;font-size:30px;letter-spacing:1px;display:block;margin:10px 0;color:#fff}
.prompt u{text-decoration-thickness:3px;text-underline-offset:5px;text-decoration-color:var(--gold);color:var(--gold)}
.prompt .words{display:block;margin:10px 0;font-family:Fredoka;font-size:23px;color:#fff;background:#0c1328;border-radius:12px;padding:10px 14px}
.ans{display:flex;gap:10px;flex-wrap:wrap;margin-top:16px;align-items:center}
.ans input{flex:1;min-width:180px;border:3px solid #4f5d8a;background:#0c1328;color:#fff;border-radius:14px;padding:12px 14px;font:inherit;font-size:22px;font-weight:800}
.ans input:focus{outline:0;border-color:#818cf8}
.ans input.words{font-size:19px;min-width:100%}
.mc{display:grid;gap:10px;margin-top:16px}
.mc button{background:var(--card2);color:var(--ink);border:3px solid var(--line);border-radius:14px;padding:12px 14px;text-align:left;font-size:19px;font-weight:800}
.mc button:hover:not(:disabled){border-color:#818cf8}
.mc button.pick{border-color:#818cf8;background:#283968}
.mc button.right{border-color:var(--ok);background:rgba(34,197,94,.18)}
.mc button.wrong{border-color:var(--bad);background:rgba(248,113,113,.15)}
.cmpbtns{display:flex;gap:12px;margin-top:16px}
.cmpbtns button{width:84px;height:72px;font-family:Fredoka;font-size:40px;border-radius:16px;border:3px solid var(--line);background:var(--card2);color:#fff}
.cmpbtns button.right{border-color:var(--ok);background:rgba(34,197,94,.25)}
.cmpbtns button.wrong{border-color:var(--bad);background:rgba(248,113,113,.2)}
.cmpshow{font-family:Fredoka;font-size:30px;display:flex;align-items:center;gap:16px;flex-wrap:wrap;margin:10px 0}
.cmpshow .box{width:60px;height:56px;border:3px dashed #6b7aa8;border-radius:12px;display:grid;place-items:center;color:var(--gold)}

.order .pool,.order .slots{display:flex;flex-wrap:wrap;gap:10px;margin-top:12px;min-height:58px}
.order .slots{background:#0c1328;border-radius:14px;padding:10px;counter-reset:s}
.order .chipn{font-family:Fredoka;font-size:22px;background:var(--card2);border:3px solid #4f5d8a;border-radius:12px;padding:8px 14px;color:#fff}
.order .slot{min-width:92px;height:52px;border:3px dashed #3f4c75;border-radius:12px;display:grid;place-items:center;font-family:Fredoka;font-size:22px;color:#fff;position:relative}
.order .slot.full{border-style:solid;border-color:#818cf8;background:#283968;cursor:pointer}
.order .lbl{color:var(--mute);font-size:14px;margin-top:10px}

.tools{display:flex;gap:10px;flex-wrap:wrap;margin-top:14px}
.tools button{background:none;border:2px solid var(--line);color:var(--mute);border-radius:12px;padding:8px 12px;font-weight:800;font-size:15px}
.tools button:hover{color:#fff;border-color:#6b7aa8}
.hint{margin-top:12px}

.fb{margin-top:16px;border-radius:16px;padding:14px 16px}
.fb.ok{background:rgba(34,197,94,.14);border:2px solid var(--ok)}
.fb.no{background:rgba(248,113,113,.1);border:2px solid var(--bad)}
.fb h3{font-size:22px;margin-bottom:6px}
.fb.ok h3{color:#86efac}.fb.no h3{color:#fca5a5}
.fb .yours{color:var(--mute);font-size:15px}
.fb .correct{font-size:19px;margin:6px 0}
.fb .correct b{color:#86efac;font-family:Fredoka;font-size:22px}
.steps{background:#0c1328;border-radius:12px;padding:10px 14px;margin:10px 0;line-height:1.7}
.steps .ln{display:block}
.steps .hl{color:var(--gold)}
.steps .gr{color:#86efac}
.mono{font-family:ui-monospace,Menlo,Consolas,monospace;font-weight:700}
table.cols{border-collapse:collapse;font-family:ui-monospace,Menlo,Consolas,monospace;font-size:20px;margin:8px 0}
table.cols td{padding:0 1px;text-align:center;min-width:16px}
table.cols td.pad{color:#60a5fa}
table.cols tr.tot td{border-top:3px solid #c7d2fe}
table.cols td.op{color:var(--mute);padding-right:8px}
.wordfix span{display:inline-block;margin:2px 3px 2px 0;padding:1px 6px;border-radius:7px}
.wordfix .w-ok{background:rgba(34,197,94,.15)}
.wordfix .w-bad{background:rgba(248,113,113,.3);text-decoration:line-through}
.wordfix .w-fix{background:rgba(34,197,94,.3);color:#bbf7d0}
.period{display:flex;gap:6px;flex-wrap:wrap;margin:8px 0}
.period div{background:#283968;border-radius:10px;padding:6px 10px;text-align:center}
.period div b{display:block;font-family:Fredoka;font-size:24px;letter-spacing:2px}
.period div small{color:var(--mute);font-size:12px}
.period div b .z{color:#60a5fa}

/* ------------------------------------------------------------ results */
.res{text-align:center;background:var(--card);border-radius:22px;padding:24px 18px;border:2px solid var(--line)}
.res .big{font-family:Fredoka;font-size:56px;line-height:1}
.res .stars{font-size:46px;letter-spacing:6px;margin:8px 0}
.res .msg{font-size:19px;margin:8px auto 16px;max-width:520px}
.res .row{justify-content:center}
.unlock{margin:16px auto;max-width:520px;border-radius:18px;padding:16px;background:linear-gradient(135deg,#ca8a04,#ea580c);color:#fff;animation:pop .6s}
.unlock b{font-family:Fredoka;font-size:28px;display:block}
@keyframes pop{0%{transform:scale(.6);opacity:0}70%{transform:scale(1.06)}100%{transform:scale(1);opacity:1}}
.missed{text-align:left;margin-top:20px}
.missed details{background:var(--card2);border-radius:14px;padding:10px 14px;margin:8px 0}
.missed summary{cursor:pointer;font-weight:800}
.skillbars{text-align:left;margin:16px auto 0;max-width:560px}
.skillbars .sb{display:flex;justify-content:space-between;padding:4px 0;border-bottom:1px solid var(--line);font-size:15px}
.confetti{position:fixed;inset:0;pointer-events:none;z-index:50;overflow:hidden}
.confetti i{position:absolute;top:-20px;width:10px;height:16px;border-radius:2px;animation:fall linear forwards}
@keyframes fall{to{transform:translateY(110vh) rotate(720deg)}}

@media (max-width:520px){
  .hero h1{font-size:25px}
  .prompt{font-size:19px}.prompt .num{font-size:26px}
  .lvl .nm{font-size:19px}
  .cmpbtns button{width:72px;height:62px}
}