*{box-sizing:border-box}
:root{
  --bg:#07111f;--panel:#0f1c2e;--panel2:#15263c;--text:#f8fafc;
  --muted:#a8b6c9;--accent:#52e28b;--accent2:#63c7ff;--danger:#ff6b6b;
  --warn:#f7c45c;--line:rgba(255,255,255,.10)
}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  background:
    radial-gradient(circle at 10% 0%,rgba(30,96,180,.24),transparent 32%),
    radial-gradient(circle at 90% 20%,rgba(27,181,111,.14),transparent 26%),
    var(--bg);color:var(--text);min-height:100vh
}
button,input,a{font:inherit}
.app{max-width:1050px;margin:auto;padding:24px}
.topbar{display:flex;justify-content:space-between;align-items:center;gap:22px;flex-wrap:wrap;margin-bottom:22px}
.brand,.eyebrow{font-size:.78rem;font-weight:900;letter-spacing:.12em;color:var(--accent2)}
h1{margin:4px 0 0;font-size:clamp(2rem,5vw,3rem);line-height:1}
.topbar p{margin:8px 0 0;color:var(--muted)}
.scorebox{background:rgba(255,255,255,.07);padding:12px 16px;border:1px solid var(--line);border-radius:14px;display:flex;gap:18px}
.card{background:linear-gradient(180deg,rgba(15,28,46,.96),rgba(12,23,39,.96));border:1px solid var(--line);border-radius:22px;padding:28px;box-shadow:0 20px 60px rgba(0,0,0,.28)}
.compact{padding:16px 20px}
.hero{display:grid;grid-template-columns:1.15fr .85fr;gap:28px;align-items:center}
.hero h2{font-size:clamp(1.7rem,4vw,2.5rem);line-height:1.08;margin:14px 0}
.hero p{color:var(--muted);line-height:1.65}
.pill{display:inline-block;background:rgba(99,199,255,.13);color:#bfe9ff;border:1px solid rgba(99,199,255,.3);padding:7px 10px;border-radius:999px;font-size:.75rem;font-weight:900}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:20px}
.primary,.secondary,.ghost{
  border:0;border-radius:12px;padding:13px 18px;font-weight:800;cursor:pointer;
  transition:.2s transform,.2s opacity,.2s border-color;text-decoration:none;display:inline-flex;align-items:center;justify-content:center
}
.primary{background:linear-gradient(90deg,var(--accent),#34c970);color:#062114}
.secondary{background:#213a59;color:#fff;border:1px solid rgba(255,255,255,.08)}
.ghost{background:transparent;color:#dce8f5;border:1px solid rgba(255,255,255,.16)}
button:hover,a.primary:hover{transform:translateY(-1px);opacity:.96}
.small{padding:8px 12px;font-size:.84rem}
.full{width:100%;margin-top:10px}
.topic-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.topic-tile{padding:13px;border-radius:14px;background:#13253b;border:1px solid var(--line);font-size:.88rem;min-height:68px}
.topic-tile strong{display:block;margin-bottom:4px}
.topic-tile span{color:var(--muted);font-size:.78rem}
.topic-tile.locked{opacity:.62}
.leaderboard-card{margin-top:18px}
.section-head{display:flex;justify-content:space-between;align-items:center;gap:12px}
.section-head h2{margin:5px 0}
.table{width:100%;border-collapse:collapse;margin-top:12px}
.table th,.table td{text-align:left;padding:11px 9px;border-bottom:1px solid var(--line)}
.table th{color:var(--muted);font-size:.78rem;text-transform:uppercase}
.empty{color:var(--muted);padding:18px 0}
.hidden{display:none!important}
.game{margin-top:18px}
.level-row{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap}
.progress{height:10px;background:#263b55;border-radius:999px;overflow:hidden;margin-top:12px}
#progressBar{height:100%;width:0;background:linear-gradient(90deg,var(--accent2),var(--accent));transition:.3s}
.question-card{margin-top:15px}
.question-meta{display:flex;justify-content:space-between;align-items:center;gap:12px}
.badge{display:inline-block;padding:6px 10px;border-radius:999px;background:#214d87;color:#d7ebff;font-size:.78rem;font-weight:900}
.level-score{color:var(--muted);font-size:.9rem}
#question{font-size:clamp(1.35rem,3vw,1.8rem);line-height:1.35;margin-top:20px}
.options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:22px}
.option{text-align:left;padding:16px;border-radius:14px;border:1px solid #385270;background:#152b45;color:#fff;cursor:pointer;min-height:60px}
.option:hover{border-color:var(--accent2);background:#1a3554}
.option.correct{background:#154c31;border-color:var(--accent)}
.option.wrong{background:#5b2027;border-color:var(--danger)}
.option:disabled{cursor:default}
.actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:20px}
.hint{margin-top:16px;padding:14px;border-radius:12px;background:#3c2d12;color:#ffe19c;border:1px solid rgba(247,196,92,.2)}
.feedback{margin-top:14px;min-height:26px;font-weight:800}
.result-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin:22px 0}
.result-grid div{background:#142840;padding:18px;border:1px solid var(--line);border-radius:14px;text-align:center}
.result-grid span{display:block;color:var(--muted);font-size:.83rem}
.result-grid strong{display:block;font-size:1.6rem;margin-top:5px}
.name-entry{max-width:520px;margin:20px 0}
label{display:block;font-weight:800;margin:10px 0 7px}
input{width:100%;padding:13px 14px;border-radius:11px;border:1px solid #3b5674;background:#091727;color:#fff;outline:none}
input:focus{border-color:var(--accent2)}
.modal{position:fixed;inset:0;background:rgba(0,0,0,.74);display:flex;align-items:center;justify-content:center;padding:18px;z-index:50}
.modal-card{position:relative;width:min(520px,100%);max-height:92vh;overflow:auto;background:#0e1e31;border:1px solid var(--line);border-radius:20px;padding:28px;box-shadow:0 30px 80px rgba(0,0,0,.5)}
.close{position:absolute;right:14px;top:10px;background:transparent;border:0;color:white;font-size:2rem;cursor:pointer}
.link-btn{width:100%;margin:10px 0}
.divider{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:.78rem;margin:14px 0}
.divider:before,.divider:after{content:"";height:1px;background:var(--line);flex:1}
.security-note{display:block;color:var(--muted);margin-top:12px;line-height:1.4}
.certificate-wrap{width:min(760px,100%)}
.certificate{background:#fff;color:#132238;padding:44px 28px;text-align:center;border:10px double #233f63;min-height:500px;display:flex;flex-direction:column;align-items:center;justify-content:center}
.cert-mark{font-size:3rem}.cert-brand{font-weight:900;letter-spacing:.12em;color:#355d86}
.certificate h2{font-family:Georgia,serif;font-size:2.5rem;margin:14px 0}
.certificate h3{font-family:Georgia,serif;font-size:2rem;border-bottom:1px solid #8ca0b5;min-width:70%;padding-bottom:8px}
.certificate h4{font-size:1.3rem}.cert-score{font-size:1.1rem}.cert-date{color:#60758c}
.cert-sign{margin-top:18px;font-family:Georgia,serif;font-style:italic;font-size:1.2rem}
footer{text-align:center;color:#72879e;margin:22px 0 4px;font-size:.83rem}
@media(max-width:760px){
  .app{padding:14px}.card{padding:20px}.hero{grid-template-columns:1fr}.topic-grid{grid-template-columns:1fr 1fr}
  .options{grid-template-columns:1fr}.scorebox{width:100%;justify-content:space-between}.result-grid{grid-template-columns:1fr}
}
@media(max-width:430px){.topic-grid{grid-template-columns:1fr}}
@media print{
  body *{visibility:hidden!important}
  #certificateModal,#certificateModal *{visibility:visible!important}
  #certificateModal{position:absolute;inset:0;background:white;padding:0}
  .modal-card{box-shadow:none;border:0;max-height:none;width:100%;padding:0}
  .certificate{min-height:100vh;border-width:12px}
  .no-print{display:none!important}
}

.level-picker{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
.level-btn{background:#132b45;color:#fff;border:1px solid rgba(255,255,255,.12);padding:14px;border-radius:14px;text-align:left;cursor:pointer}
.level-btn:hover{border-color:#63c7ff}.level-btn strong{display:block}.level-btn span{font-size:.8rem;color:#a8b6c9}
.answer-input-area{margin-top:20px;max-width:520px}.input-row{display:flex;align-items:center;gap:10px;margin:10px 0}
.input-row label{min-width:55px}.input-row input{max-width:180px}
.graph-layout{display:grid;grid-template-columns:minmax(0,560px) 1fr;gap:18px;align-items:start;margin-top:18px}
#graphCanvas{width:100%;height:auto;background:#fff;border-radius:14px;border:1px solid #55708c;touch-action:none}
.graph-help{color:#a8b6c9;font-size:.82rem}.graph-tools{display:flex;flex-direction:column;gap:10px}
@media(max-width:760px){.level-picker{grid-template-columns:1fr}.graph-layout{grid-template-columns:1fr}}