:root{
  --bg:#0f1720;
  --card:#0b1220;
  --accent:#42a5f5;
  --muted:#9aa7b2;
  --text:#e6eef6;
  --input-bg:#141c28;
  --input-border:rgba(255,255,255,0.12);
}
*{box-sizing:border-box}
html{height:100%;color-scheme:dark}
body.page{font-family:Inter,Segoe UI,Helvetica,Arial,sans-serif;background:linear-gradient(180deg,#071021 0%,#0b1220 100%);color:var(--text);min-height:100%;margin:0;display:flex;flex-direction:column}
.page-main{flex:1 0 auto;width:920px;max-width:94%;margin:0 auto;padding:28px 28px 32px}
h1{margin:0 0 12px;font-size:clamp(1.25rem,2.5vw,1.75rem)}
.app-header{display:flex;align-items:flex-start;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-bottom:8px}
.app-header h1{flex:1 1 12rem;min-width:0}
.main-nav{display:flex;gap:8px;flex-wrap:wrap;flex:1 1 auto;justify-content:flex-end;align-items:center}
.main-nav .menu-btn{background:transparent;color:var(--text);border:1px solid rgba(255,255,255,0.08);padding:8px 10px;border-radius:8px;cursor:pointer;font-size:14px}
.main-nav .menu-btn-home{display:inline-flex;align-items:center;gap:6px}
.main-nav .menu-btn-home .fa-house{font-size:0.95em;opacity:0.9}
.main-nav .menu-btn.active{background:var(--accent);color:#042233;border-color:transparent}

.controls-wrap{margin-bottom:20px;display:flex;flex-direction:column;gap:10px}
.quiz-toolbar{display:grid;grid-template-columns:1fr auto;gap:12px 16px;padding:12px 14px;border-radius:10px;background:rgba(255,255,255,0.03);border:1px solid rgba(255,255,255,0.06);align-items:center}
@media (min-width:720px){
  .quiz-toolbar{grid-template-columns:1fr auto auto}
}
.quiz-toolbar-summary{margin:0;color:var(--muted);grid-column:1/-1}
@media (min-width:720px){
  .quiz-toolbar-summary{grid-column:auto}
}
.quiz-toolbar-actions{display:flex;flex-wrap:wrap;gap:8px;justify-content:flex-end}
.quiz-toolbar .timer-controls{padding:0;min-width:0;grid-column:1/-1;align-items:flex-start}
@media (min-width:720px){
  .quiz-toolbar .timer-controls{grid-column:auto;justify-self:start;text-align:left}
}

.controls{display:block;padding:16px 18px;border-radius:10px;background:rgba(255,255,255,0.02);border:1px solid rgba(255,255,255,0.04)}
.setup-grid{display:flex;flex-direction:column;gap:12px;min-width:0}
.form-row{display:grid;grid-template-columns:minmax(140px,1fr) minmax(160px,220px);gap:10px 16px;align-items:center}
@media (max-width:520px){
  .form-row{grid-template-columns:1fr}
}
.form-row label{margin:0;font-size:14px;line-height:1.35}
.form-row--check{grid-template-columns:1fr}
.form-row--action{grid-template-columns:1fr;margin-top:4px}
.form-row--action button{justify-self:start;width:100%;max-width:280px}
.check-label{display:inline-flex;align-items:center;gap:8px;margin:0;cursor:pointer}

select,
#questionCount,#answerMode,#langSel{
  width:100%;
  min-width:0;
  padding:9px 32px 9px 10px;
  font-size:15px;
  line-height:1.3;
  border-radius:8px;
  border:1px solid var(--input-border);
  background-color:var(--input-bg);
  color:var(--text);
  appearance:none;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='%239aa7b2' d='M1 1l5 5 5-5'/%3E%3C/svg%3E");
  background-repeat:no-repeat;
  background-position:right 10px center;
  cursor:pointer;
}
select:focus,
#questionCount:focus,#answerMode:focus,#langSel:focus{
  outline:2px solid rgba(66,165,245,0.45);
  outline-offset:1px;
}
select option{
  background-color:#141c28;
  color:var(--text);
}

.timer-controls{display:flex;flex-direction:column;align-items:flex-start;gap:10px;min-width:200px;padding-top:4px}
button{background:var(--accent);border:none;padding:10px 14px;color:#042233;border-radius:8px;font-weight:600;cursor:pointer;font-size:14px}
button:hover{filter:brightness(1.05)}
.btn-secondary{background:transparent;color:var(--text);border:1px solid rgba(255,255,255,0.14)}
.btn-secondary:hover{background:rgba(255,255,255,0.04);filter:none}

.timers{color:var(--muted);font-size:14px;line-height:1.5}
.timers.vertical{display:flex;flex-direction:column;align-items:flex-start;gap:4px}
.card{background:rgba(255,255,255,0.03);padding:18px;border-radius:10px;margin-top:12px;border:1px solid rgba(255,255,255,0.04)}
.hidden{display:none!important}
#questionCard{min-height:120px}
#questionCard .form{display:grid;gap:10px;margin-top:14px}
#questionCard .form label{margin:0}
.actions{display:flex;gap:12px;margin-top:12px;flex-wrap:wrap}
#stepsCard{margin-top:12px;background:rgba(255,255,255,0.02);padding:12px}
label{display:block;margin:8px 0;font-size:14px}
input[type=text]{width:100%;padding:8px 10px;border-radius:6px;border:1px solid var(--input-border);background:var(--input-bg);color:var(--text)}
input[type=checkbox]{accent-color:var(--accent);width:16px;height:16px}
.mc-opt{display:flex;align-items:center;gap:8px;margin:8px 0;cursor:pointer}
.small{font-size:13px;color:var(--muted);line-height:1.45}
.result-correct{color:#84f0a1}
.result-wrong{color:#ff9b9b}
.explain{margin-top:8px;color:var(--muted);font-size:13px}
.site-footer{flex-shrink:0;width:100%;border-top:1px solid rgba(255,255,255,0.06);background:rgba(0,0,0,0.25);margin-top:auto}
.app-footer{max-width:920px;margin:0 auto;padding:22px 28px 28px;color:var(--muted);font-size:13px}
.app-footer-inner{display:flex;justify-content:center;gap:22px;align-items:stretch;flex-wrap:wrap;text-align:center}
.app-footer .col{padding:8px 18px;display:flex;flex-direction:column;justify-content:center;gap:4px}
.app-footer .col:not(:first-child){border-left:1px solid rgba(255,255,255,0.06)}
.app-footer .company{font-weight:700;color:var(--text)}
.app-footer a{color:var(--accent);text-decoration:none}
.app-footer a:hover{text-decoration:underline}
.app-footer a.btn-footer-contact{color:#042233;text-decoration:none}
.app-footer a.btn-footer-contact:hover{text-decoration:none;filter:brightness(1.08)}
.footer-copy,.footer-disclaimer{text-align:center;margin-top:12px}
.footer-disclaimer{margin-top:8px}
.footer-meta{text-align:center;margin-top:16px;padding-top:14px;border-top:1px solid rgba(255,255,255,0.06)}
.footer-oss{margin:0 0 10px;color:var(--text);line-height:1.5;max-width:36rem;margin-left:auto;margin-right:auto}
.footer-bug-row{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:10px;margin-top:12px}
.footer-bug-label{font-size:14px;color:var(--muted);display:inline-flex;align-items:center;gap:8px}
.footer-bug-label .fa-bug{color:#ff8a80;font-size:1.05em}
.btn-footer-contact{display:inline-block;padding:8px 14px;border-radius:8px;background:var(--accent);color:#042233;font-weight:600;font-size:13px;text-decoration:none}
.btn-footer-contact:hover{filter:brightness(1.08)}
.question-types{border:1px solid rgba(255,255,255,0.06);border-radius:8px;padding:12px 14px;margin:0}
.question-types legend{padding:0 6px;font-size:14px;color:var(--muted)}
.question-types-grid{display:flex;flex-wrap:wrap;gap:6px 14px}
.question-types label{display:inline-flex;align-items:center;gap:6px;margin:0;font-size:13px;cursor:pointer}
.question-types label:has(input:disabled){opacity:0.45;cursor:not-allowed}
.mc-type-warning{margin:10px 0 0;padding:10px 12px;border-radius:8px;font-size:13px;line-height:1.45;color:var(--text);background:rgba(255,200,100,0.08);border:1px solid rgba(255,200,100,0.22)}
.session-stats{margin-top:14px}
.session-stats table{width:100%;border-collapse:collapse;font-size:13px;margin-top:8px}
.session-stats th,.session-stats td{padding:8px 10px;text-align:left;border-bottom:1px solid rgba(255,255,255,0.06)}
.session-stats th{color:var(--muted);font-weight:600}
.weak-points{margin-top:10px}
.hint-wrong{margin-top:6px;padding:8px 10px;border-radius:6px;background:rgba(255,155,155,0.08);border:1px solid rgba(255,155,155,0.15);font-size:13px;color:var(--muted)}
.explain-steps{margin:10px 0 0;padding-left:1.25rem;color:var(--muted);font-size:13px;line-height:1.55}
.explain-steps li{margin-bottom:6px}
.steps-available-link{background:none;border:none;padding:0;margin:0;font:inherit;cursor:pointer;color:var(--accent);text-align:left}
.steps-available-link em{font-style:italic;color:inherit}
.steps-available-link:hover em,.steps-available-link:focus-visible em{text-decoration:underline}
.steps-available-link:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:2px}
.result-steps-panel{margin-top:4px}

@media (max-width:640px){
  .page-main{padding:18px 16px 24px}
  .app-footer{padding:18px 16px 24px}
  .app-footer-inner{flex-direction:column;align-items:center;gap:0}
  .app-footer .col{width:100%;border-left:none!important;padding:10px 0}
  .app-footer .col:not(:first-child){border-top:1px solid rgba(255,255,255,0.06);margin-top:4px}
  .form-row--action button{max-width:none;width:100%}
  .quiz-toolbar{grid-template-columns:1fr}
  .quiz-toolbar-actions{width:100%;justify-content:stretch}
  .quiz-toolbar-actions .btn-secondary,.quiz-toolbar-actions #newQuizToolbarBtn{flex:1 1 45%;min-width:0}
  .session-stats{overflow-x:auto;-webkit-overflow-scrolling:touch}
  .session-stats table{min-width:280px}
  .question-types-grid{flex-direction:column;align-items:flex-start}
  .main-nav{width:100%}
  .main-nav .menu-btn{flex:1 1 auto;text-align:center;min-width:0}
}