:root{
  --bg:#0f1226; --bg2:#1a1f3a; --card:#1f2547; --card2:#2a3160; --accent:#7c5cff; --accent2:#22d3ee;
  --text:#f5f5ff; --muted:#b4bce0; --ok:#22c55e; --bad:#ef4444; --warn:#f59e0b;
  --easy:#22c55e; --medium:#3b82f6; --hard:#a855f7; --expert:#ef4444; --genius:#ff6b00;
  --answer-bg:#2a3160; --answer-bg-hover:#353d76; --answer-text:#f8f8ff;
  --ai:#7c5cff;
}
[data-theme="light"]{
  --bg:#f4f6ff; --bg2:#ffffff; --card:#ffffff; --card2:#f1f3fb; --accent:#5b3df5; --accent2:#0891b2;
  --text:#0f1226; --muted:#475569; --ok:#16a34a; --bad:#dc2626; --warn:#d97706;
  --answer-bg:#f1f3fb; --answer-bg-hover:#e4e8f5; --answer-text:#0f1226;
}
*{box-sizing:border-box;margin:0;padding:0}
html,body{height:100%}
body{
  font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;
  background:linear-gradient(135deg,var(--bg) 0%,var(--bg2) 100%);
  color:var(--text);min-height:100vh;padding:20px;transition:.3s;
}
.container{max-width:900px;margin:0 auto}
.header{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;flex-wrap:wrap;gap:10px}
.logo{font-size:28px;font-weight:800;background:linear-gradient(45deg,var(--accent),var(--accent2));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.logo small{font-size:12px;color:var(--muted);font-weight:600;letter-spacing:1px}
.controls{display:flex;gap:8px;flex-wrap:wrap}
.btn{
  background:var(--card);color:var(--text);border:1px solid rgba(255,255,255,.1);
  padding:10px 16px;border-radius:10px;cursor:pointer;font-weight:600;font-size:14px;
  transition:.2s;display:inline-flex;align-items:center;gap:6px;
}
.btn:hover{transform:translateY(-1px);box-shadow:0 4px 12px rgba(0,0,0,.2)}
.btn.primary{background:linear-gradient(45deg,var(--accent),var(--accent2));border:none;color:#fff}
.btn.danger{background:var(--bad);color:#fff;border:none}
.btn:disabled{opacity:.5;cursor:not-allowed}
.card{background:var(--card);border-radius:16px;padding:24px;box-shadow:0 8px 32px rgba(0,0,0,.2);border:1px solid rgba(255,255,255,.05)}
.screen{display:none}
.screen.active{display:block;animation:fadeIn .3s}
@keyframes fadeIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* Home */
.hero{text-align:center;padding:30px 20px}
.hero h1{font-size:42px;margin-bottom:8px;background:linear-gradient(45deg,var(--accent),var(--accent2));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero p{color:var(--muted);font-size:16px;margin-bottom:20px}
.version-badge{display:inline-block;background:linear-gradient(45deg,var(--accent),var(--accent2));color:#fff;padding:4px 12px;border-radius:20px;font-size:12px;font-weight:700;margin-bottom:14px;letter-spacing:1px}
.difficulty-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:14px;margin-top:20px}
/* v10.35 P1-18: separátor pro speciální režim (Nadčlověk) — oddělený vizuálně od standardních obtížností */
.diff-separator{grid-column:1/-1;margin-top:8px;padding:6px 0 4px;font-size:12px;text-transform:uppercase;letter-spacing:1.2px;color:var(--muted);text-align:center;border-top:1px solid var(--card2);position:relative}
.diff-card{background:var(--card2);border:2px solid transparent;border-radius:14px;padding:20px;cursor:pointer;transition:.2s;text-align:center;color:var(--text)}
.diff-card:hover{transform:translateY(-3px);border-color:var(--accent)}
.diff-card.easy:hover{border-color:var(--easy)}
.diff-card.medium:hover{border-color:var(--medium)}
.diff-card.hard:hover{border-color:var(--hard)}
.diff-card.expert:hover{border-color:var(--expert)}
.diff-card.genius:hover{border-color:#ff6b00}
.diff-icon{font-size:36px;margin-bottom:8px}
.diff-name{font-size:18px;font-weight:700;margin-bottom:4px}
.diff-desc{font-size:12px;color:var(--muted);line-height:1.4}

/* AI generate panel on home */
.ai-panel{background:linear-gradient(135deg,rgba(124,92,255,.12),rgba(34,211,238,.08));border:1px solid rgba(124,92,255,.3);border-radius:16px;padding:20px;margin-top:20px}
.ai-panel-title{font-size:16px;font-weight:700;margin-bottom:12px;display:flex;align-items:center;gap:8px}
.ai-panel-title .ai-badge{background:linear-gradient(45deg,var(--accent),var(--accent2));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.ai-form{display:grid;grid-template-columns:1fr 1fr auto;gap:10px;align-items:end;flex-wrap:wrap}
.ai-form select,.ai-form input{background:var(--card2);color:var(--text);border:1px solid rgba(255,255,255,.1);padding:10px 12px;border-radius:10px;font-size:14px;font-family:inherit}
.ai-form input::placeholder{color:var(--muted)}
.ai-no-key{color:var(--warn);font-size:12px;margin-top:8px;display:none}
.ai-no-key.show{display:block}

/* Game */
.game-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px;flex-wrap:wrap;gap:10px}
.stat-pill{background:var(--card2);color:var(--text);padding:8px 14px;border-radius:20px;font-size:13px;font-weight:600;display:inline-flex;align-items:center;gap:6px}
.timer{font-variant-numeric:tabular-nums}
.timer.warn{color:var(--warn)}
.timer.bad{color:var(--bad);animation:pulse 1s infinite}
@keyframes pulse{50%{transform:scale(1.06)}}
.progress{height:8px;background:rgba(255,255,255,.08);border-radius:10px;overflow:hidden;margin-bottom:18px}
.progress-bar{height:100%;background:linear-gradient(90deg,var(--accent),var(--accent2));width:0%;transition:.3s}
.question-meta{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px;font-size:12px;color:var(--muted);flex-wrap:wrap;gap:8px}
.diff-badge{padding:3px 10px;border-radius:10px;font-weight:700;font-size:11px;letter-spacing:.5px}
.diff-badge.d1{background:rgba(34,197,94,.2);color:var(--easy)}
.diff-badge.d2{background:rgba(59,130,246,.2);color:var(--medium)}
.diff-badge.d3{background:rgba(168,85,247,.2);color:var(--hard)}
.diff-badge.d4{background:rgba(239,68,68,.2);color:var(--expert)}
.diff-badge.d5{background:rgba(255,107,0,.2);color:#ff6b00}
.cat-badge{background:var(--card2);color:var(--text);padding:4px 12px;border-radius:10px;font-weight:600}
.ai-generated-badge{background:linear-gradient(45deg,rgba(124,92,255,.3),rgba(34,211,238,.2));color:var(--accent2);padding:4px 12px;border-radius:10px;font-weight:600;font-size:11px;border:1px solid rgba(124,92,255,.3)}
.question{font-size:22px;font-weight:600;margin-bottom:20px;line-height:1.45;color:var(--text)}
.answers{display:grid;gap:10px}
.answer{background:var(--answer-bg);color:var(--answer-text);border:2px solid rgba(255,255,255,.06);border-radius:12px;padding:14px 18px;cursor:pointer;transition:.15s;font-size:15px;font-weight:500;text-align:left;display:flex;align-items:center;gap:12px;line-height:1.4}
.answer:hover:not(.disabled){background:var(--answer-bg-hover);border-color:var(--accent);transform:translateX(4px)}
.answer.correct{background:rgba(34,197,94,.15);border-color:var(--ok)}
.answer.wrong{background:rgba(239,68,68,.15);border-color:var(--bad)}
.answer.disabled{cursor:not-allowed;opacity:.6}
.answer-letter{width:30px;height:30px;border-radius:8px;background:var(--accent);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800;font-size:13px;flex-shrink:0}

/* AI helpers */
.helpers{display:flex;gap:8px;margin-top:16px;flex-wrap:wrap}
.helper{background:var(--card2);color:var(--text);border:1px solid rgba(255,255,255,.08);padding:8px 14px;border-radius:10px;cursor:pointer;font-size:13px;font-weight:600;transition:.15s;display:inline-flex;align-items:center;gap:6px}
.helper:hover:not(:disabled){background:var(--accent);color:#fff}
.helper.ai-helper{border-color:rgba(124,92,255,.4)}
.helper.ai-helper:hover:not(:disabled){background:linear-gradient(45deg,var(--accent),var(--accent2))}
.helper:disabled{opacity:.4;cursor:not-allowed}

/* AI hint bubble */
.ai-hint{display:none;background:linear-gradient(135deg,rgba(124,92,255,.12),rgba(34,211,238,.08));border:1px solid rgba(124,92,255,.3);border-radius:12px;padding:14px 16px;margin-top:12px;font-size:14px;line-height:1.6}
.ai-hint.show{display:block;animation:fadeIn .2s}
.ai-hint-label{font-size:11px;font-weight:700;color:var(--accent2);letter-spacing:1px;margin-bottom:6px;display:block}
.ai-hint-text{color:var(--text)}
.ai-thinking{display:inline-flex;align-items:center;gap:6px;color:var(--muted);font-size:13px}
.ai-thinking::after{content:'';width:14px;height:14px;border:2px solid var(--accent);border-top-color:transparent;border-radius:50%;animation:spin .7s linear infinite;display:inline-block}
@keyframes spin{to{transform:rotate(360deg)}}

.feedback{margin-top:14px;padding:14px 16px;border-radius:12px;font-size:14px;display:none;line-height:1.5}
.feedback.show{display:block;animation:fadeIn .2s}
.feedback.ok{background:rgba(34,197,94,.12);color:var(--ok);border-left:4px solid var(--ok)}
.feedback.bad{background:rgba(239,68,68,.12);color:var(--bad);border-left:4px solid var(--bad)}
.feedback .verdict{font-weight:700;font-size:15px;margin-bottom:6px;display:block}
.feedback .explanation{color:var(--text);font-weight:400;margin-top:6px;display:block}
.feedback .ai-exp{color:var(--muted);font-style:italic;font-size:13px;margin-top:8px;display:block;border-top:1px solid rgba(255,255,255,.08);padding-top:8px}
.next-btn-wrap{margin-top:14px;text-align:right;display:none}
.next-btn-wrap.show{display:block;animation:fadeIn .2s}

/* Result */
.result-hero{text-align:center;padding:20px}
.result-emoji{font-size:72px;margin-bottom:10px}
.result-score{font-size:48px;font-weight:800;background:linear-gradient(45deg,var(--accent),var(--accent2));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.result-stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px;margin:20px 0}
.stat-box{background:var(--card2);padding:14px;border-radius:12px;text-align:center}
.stat-value{font-size:24px;font-weight:800;color:var(--accent)}
.stat-label{font-size:12px;color:var(--muted);margin-top:4px}
.achievements{margin-top:16px}
.achievement{display:inline-flex;align-items:center;gap:8px;background:var(--card2);color:var(--text);padding:8px 14px;border-radius:20px;margin:4px;font-size:13px;font-weight:600}

/* Stats */
.stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:12px}
.cat-stats{margin-top:16px}
.cat-row{display:flex;justify-content:space-between;align-items:center;padding:10px;background:var(--card2);border-radius:8px;margin-bottom:6px;font-size:14px}

/* Settings screen */
.settings-group{margin-bottom:20px}
.settings-label{font-size:12px;font-weight:700;color:var(--muted);letter-spacing:1px;text-transform:uppercase;margin-bottom:8px;display:block}
.settings-input{width:100%;background:var(--card2);color:var(--text);border:1px solid rgba(255,255,255,.1);padding:12px 14px;border-radius:10px;font-size:14px;font-family:inherit}
.settings-input::placeholder{color:var(--muted)}
.key-status{font-size:12px;margin-top:6px;display:flex;align-items:center;gap:6px}
.key-status.ok{color:var(--ok)}
.key-status.empty{color:var(--muted)}

/* Toast */
.toast{position:fixed;bottom:20px;left:50%;transform:translateX(-50%);background:var(--card);padding:12px 20px;border-radius:10px;box-shadow:0 8px 24px rgba(0,0,0,.3);z-index:1000;display:none;font-weight:600;max-width:90vw;text-align:center}
.toast.show{display:block;animation:slideUp .3s}
@keyframes slideUp{from{transform:translate(-50%,20px);opacity:0}to{transform:translate(-50%,0);opacity:1}}

/* Bod b: správná odpověď explicitně zobrazená ve feedback bloku */
.correct-answer-row{
  display:block;
  margin:6px 0 4px;
  padding:8px 12px;
  background:rgba(34,197,94,.15);
  border-left:3px solid var(--ok);
  border-radius:6px;
  font-size:15px;
  color:var(--text);
}
.correct-answer-row strong{color:var(--ok);font-weight:700}

/* Bod B (v10.8): Diagnostický panel — sbalitelný, na home obrazovce */
.diagnostic-panel{
  margin-top:14px;
  background:var(--card);
  border:1px solid rgba(255,255,255,.08);
  border-radius:12px;
  padding:0;
  font-size:13px;
}
.diagnostic-summary{
  display:flex;align-items:center;gap:8px;
  padding:12px 16px;
  cursor:pointer;
  user-select:none;
  list-style:none;
  font-weight:600;
  color:var(--muted);
}
.diagnostic-summary::-webkit-details-marker{display:none}
.diagnostic-summary::marker{display:none}
.diagnostic-summary::before{
  content:'▸';
  display:inline-block;
  transition:transform .2s;
  color:var(--muted);
  font-size:11px;
}
.diagnostic-panel[open] .diagnostic-summary::before{transform:rotate(90deg)}
.diag-icon{font-size:14px}
.diag-title{flex:1}
.diag-status{
  font-size:11px;
  padding:2px 8px;
  border-radius:10px;
  background:rgba(255,255,255,.06);
  color:var(--muted);
  font-weight:600;
}
.diag-status.ok{background:rgba(34,197,94,.18);color:var(--ok)}
.diag-status.warn{background:rgba(239,68,68,.18);color:#ef4444}
.diag-status.checking{background:rgba(59,130,246,.18);color:#60a5fa}
.diagnostic-body{
  padding:4px 16px 14px;
  border-top:1px solid rgba(255,255,255,.05);
}
.diag-row{
  display:flex;justify-content:space-between;align-items:center;
  padding:6px 0;
  border-bottom:1px dashed rgba(255,255,255,.05);
  font-family:ui-monospace,Menlo,Consolas,monospace;
  font-size:12px;
}
.diag-row:last-of-type{border-bottom:none}
.diag-label{color:var(--muted)}
.diag-value{color:var(--text);font-weight:600}
.diag-value.ok{color:var(--ok)}
.diag-value.warn{color:#ef4444}
.diag-mismatch-hint{
  margin-top:10px;
  padding:10px 12px;
  background:rgba(239,68,68,.12);
  border-left:3px solid #ef4444;
  border-radius:6px;
  color:var(--text);
  font-size:12px;
  line-height:1.5;
}
.diag-actions{
  display:flex;gap:8px;flex-wrap:wrap;
  margin-top:12px;
}
.diag-actions .btn{font-size:12px;padding:6px 12px}

/* === v10.13: Křížová kontrola (cross-check) ============================ */
.cross-check-slot{
  display:flex;flex-direction:column;gap:10px;
  margin-top:14px;padding-top:14px;
  border-top:1px dashed rgba(255,255,255,.18);
}
.cross-check-btn{
  align-self:flex-start;
  padding:8px 14px;font-size:13px;font-weight:600;
  background:linear-gradient(135deg,#7c3aed 0%,#3b82f6 100%);
  color:#fff;border:none;border-radius:8px;
  cursor:pointer;transition:transform .15s ease,opacity .2s;
}
.cross-check-btn:hover:not(:disabled){transform:translateY(-1px)}
.cross-check-btn:disabled{opacity:.7;cursor:wait}
.cross-check-result{
  padding:12px 14px;border-radius:10px;
  background:rgba(124,58,237,.10);
  border:1px solid rgba(124,58,237,.35);
  font-size:13px;line-height:1.55;
}
.cross-check-title{
  font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.6px;
  color:var(--muted);margin-bottom:6px;
  display:flex;justify-content:space-between;align-items:center;gap:8px;flex-wrap:wrap;
}
.cross-check-via{
  font-size:10px;font-weight:500;color:var(--muted);
  text-transform:none;letter-spacing:0;opacity:.75;
}
.cross-check-verdict{font-weight:600;margin-bottom:6px;font-size:13px}
.cross-check-agree{color:#22c55e}
.cross-check-disagree{color:#f59e0b}
.cross-check-explanation{color:var(--text);opacity:.92}
.cross-check-loading{color:var(--muted);font-style:italic}
.cross-check-error{color:#ef4444;font-size:12px}

@media(max-width:600px){
  body{padding:12px}
  .hero h1{font-size:32px}
  .question{font-size:18px}
  .card{padding:18px}
  .ai-form{grid-template-columns:1fr 1fr;grid-template-rows:auto auto}
  .ai-form .btn{grid-column:1/-1}
}

/* ==== v10.34: Nadclovek (overhuman) ==== */
.diff.cls-overhuman{
  background:linear-gradient(135deg,#000 0%,#1a1a1a 50%,#2d1b4e 100%);
  border:2px solid #6d28d9;
  color:#fff;
  position:relative;
  overflow:hidden;
}
.diff.cls-overhuman::before{
  content:'';position:absolute;inset:0;
  background:radial-gradient(circle at 30% 20%,rgba(168,85,247,.25),transparent 60%);
  pointer-events:none;
}
.diff.cls-overhuman .diff-icon,
.diff.cls-overhuman .diff-name,
.diff.cls-overhuman .diff-desc{position:relative;z-index:1}
.diff.cls-overhuman .diff-name{
  background:linear-gradient(90deg,#a78bfa,#f0abfc,#a78bfa);
  -webkit-background-clip:text;background-clip:text;color:transparent;
  font-weight:800;letter-spacing:.5px;
}
.diff.cls-overhuman.selected{
  box-shadow:0 0 0 3px #a78bfa,0 8px 32px rgba(124,58,237,.55);
}

.overhuman-wrap{
  display:flex;flex-direction:column;gap:12px;width:100%;
}
.overhuman-input{
  width:100%;padding:14px 16px;border-radius:12px;
  background:var(--bg-soft,rgba(255,255,255,.04));
  border:2px solid rgba(168,85,247,.35);
  color:var(--text);font-size:16px;font-family:inherit;line-height:1.5;
  resize:vertical;min-height:96px;
  transition:border-color .15s,box-shadow .15s;
  box-sizing:border-box;
}
.overhuman-input:focus{
  outline:none;border-color:#a78bfa;
  box-shadow:0 0 0 3px rgba(168,85,247,.25);
}
.overhuman-input:disabled{opacity:.6;cursor:not-allowed}
.overhuman-actions{display:flex;justify-content:flex-end;gap:8px;flex-wrap:wrap}
.overhuman-submit{min-width:160px}
.overhuman-submit:disabled{opacity:.7;cursor:wait}

.overhuman-result{
  margin:8px 0;padding:14px 16px;border-radius:12px;
  border:1px solid rgba(168,85,247,.35);
  background:rgba(168,85,247,.08);
  display:flex;flex-direction:column;gap:8px;
}
.overhuman-result.overhuman-pass{
  border-color:rgba(34,197,94,.45);
  background:rgba(34,197,94,.10);
}
.overhuman-result.overhuman-fail{
  border-color:rgba(245,158,11,.45);
  background:rgba(245,158,11,.10);
}
.overhuman-verdict{font-weight:700;font-size:15px}
.overhuman-pass .overhuman-verdict{color:#22c55e}
.overhuman-fail .overhuman-verdict{color:#f59e0b}
.overhuman-ai-verdict{font-size:14px;color:var(--text);opacity:.95}
.overhuman-feedback{font-size:13px;color:var(--text);opacity:.85;line-height:1.5}

/* v10.36 (c) skip btn */
.skip-wrap{margin-top:14px;display:flex;justify-content:center}
.skip-btn{background:transparent;color:var(--muted,#888);border:1px dashed var(--border,#444);padding:8px 16px;font-size:.9em;opacity:.75}
.skip-btn:hover{opacity:1;color:var(--text,#fff);border-style:solid}