:root { --quiz-panel: rgba(10,18,33,.92); --quiz-line: rgba(148,163,184,.16); --quiz-cyan: #67e8f9; --quiz-violet: #a78bfa; }
.basics-page { min-width: 320px; padding: 0; background-color: #050816; }
.vault-back { position: fixed; top: max(16px,env(safe-area-inset-top)); left: max(16px,env(safe-area-inset-left)); z-index: 20; padding: 9px 13px; border: 1px solid rgba(148,163,184,.2); border-radius: 999px; background: rgba(5,8,22,.88); color: #a5f3fc; font-size: .76rem; font-weight: 850; backdrop-filter: blur(12px); }
.vault-back:hover { border-color: rgba(103,232,249,.5); text-decoration: none; }
.basics-shell { width: min(1120px,calc(100% - 32px)); margin: 0 auto; padding: 76px 0 64px; }
.basics-hero { position: relative; isolation: isolate; min-height: 270px; display: grid; grid-template-columns: minmax(0,1.25fr) minmax(240px,.75fr); align-items: center; gap: 32px; overflow: hidden; padding: clamp(32px,6vw,66px); border: 1px solid rgba(103,232,249,.18); border-radius: 30px; background: linear-gradient(128deg,rgba(7,18,35,.98),rgba(31,25,67,.93)); box-shadow: 0 34px 90px rgba(2,8,23,.5); }
.basics-hero::before { content:""; position:absolute; z-index:-1; inset:0; background:radial-gradient(circle at 84% 18%,rgba(167,139,250,.2),transparent 34%); }
.eyebrow { display:flex; align-items:center; gap:9px; margin-bottom:9px; color:var(--quiz-cyan); font-size:.7rem; font-weight:900; letter-spacing:.14em; text-transform:uppercase; }
.eyebrow span { width:7px; height:7px; border-radius:50%; background:#34d399; box-shadow:0 0 14px #34d399; }
.basics-hero h1 { font-size:clamp(2.25rem,5.5vw,4.4rem); letter-spacing:-.055em; line-height:1; }
.basics-hero h1 em { color:transparent; background:linear-gradient(90deg,var(--quiz-cyan),#60a5fa 50%,var(--quiz-violet)); background-clip:text; -webkit-background-clip:text; font-style:normal; }
.basics-hero>div>p:last-child { max-width:680px; margin-top:20px; color:#b8c5d8; line-height:1.7; }
.hero-signal { display:grid; place-items:center; min-height:160px; border:1px solid rgba(103,232,249,.12); border-radius:25px; background:rgba(3,10,25,.3); transform:rotate(-3deg); }
.hero-signal svg { width:88%; overflow:visible; }
.hero-signal path { fill:none; stroke:var(--quiz-cyan); stroke-width:3; stroke-linecap:round; stroke-linejoin:round; }
.quiz-status { position:sticky; top:12px; z-index:10; display:grid; grid-template-columns:minmax(0,1fr) auto; gap:11px 24px; margin:18px 0; padding:15px 18px; border:1px solid var(--quiz-line); border-radius:17px; background:rgba(7,13,25,.93); box-shadow:0 16px 40px rgba(2,8,23,.32); backdrop-filter:blur(14px); }
.status-copy { min-width:0; display:flex; align-items:baseline; gap:12px; }
.status-copy span { flex:0 0 auto; color:var(--quiz-cyan); font:850 .69rem var(--font-mono); text-transform:uppercase; }
.status-copy strong { overflow:hidden; text-overflow:ellipsis; white-space:nowrap; }
.status-score { display:flex; gap:14px; color:#aab8ca; font-size:.74rem; }
.status-score strong { color:#f8fafc; }
.progress-track { grid-column:1/-1; height:5px; overflow:hidden; border-radius:999px; background:rgba(148,163,184,.13); }
.progress-track span { display:block; width:0; height:100%; border-radius:inherit; background:linear-gradient(90deg,#22d3ee,#6366f1); transition:width .25s ease; }
.quiz-layout { display:grid; grid-template-columns:minmax(0,1fr); gap:18px; align-items:start; }
.quiz-layout.has-scope { grid-template-columns:minmax(0,1fr) minmax(330px,.58fr); }
.question-card,.scope-panel,.results-card { border:1px solid var(--quiz-line); border-radius:24px; background:var(--quiz-panel); box-shadow:0 24px 60px rgba(2,8,23,.3); }
.question-card { overflow:hidden; }
.question-heading { display:flex; align-items:center; justify-content:space-between; gap:16px; padding:17px clamp(18px,4vw,30px); border-bottom:1px solid var(--quiz-line); }
.question-heading span { color:var(--quiz-cyan); font:900 .7rem var(--font-mono); letter-spacing:.08em; }
.question-heading small { padding:5px 9px; border:1px solid rgba(167,139,250,.24); border-radius:999px; background:rgba(167,139,250,.08); color:#c4b5fd; font-size:.65rem; font-weight:850; }
.question-prompt { padding:clamp(24px,5vw,42px) clamp(18px,4vw,32px) 20px; color:#e8edf5; font-size:clamp(1.05rem,2vw,1.23rem); line-height:1.7; }
.question-prompt p+p { margin-top:14px; }
.question-prompt .formula { margin:18px 0 0; padding:18px; border:1px solid rgba(103,232,249,.14); border-radius:14px; background:rgba(2,8,23,.46); color:#f8fafc; text-align:center; font-size:1.15em; }
.answer-form { display:grid; gap:10px; padding:8px clamp(18px,4vw,32px) 28px; }
.choice-option { position:relative; display:grid; grid-template-columns:36px minmax(0,1fr); align-items:center; gap:12px; min-height:58px; padding:12px 14px; border:1px solid var(--quiz-line); border-radius:14px; background:rgba(3,10,24,.45); cursor:pointer; transition:border-color .15s,background .15s,transform .15s; }
.choice-option:hover { border-color:rgba(103,232,249,.38); transform:translateY(-1px); }
.choice-option:has(input:checked) { border-color:rgba(103,232,249,.7); background:rgba(8,145,178,.11); }
.choice-option input { position:absolute; opacity:0; }
.choice-letter { width:32px; height:32px; display:grid; place-items:center; border:1px solid rgba(148,163,184,.2); border-radius:10px; color:#a5f3fc; font:900 .75rem var(--font-mono); }
.choice-option.is-correct { border-color:rgba(52,211,153,.55); background:rgba(52,211,153,.1); }
.choice-option.is-wrong { border-color:rgba(248,113,113,.55); background:rgba(248,113,113,.08); }
.match-grid { display:grid; gap:11px; }
.match-row { display:grid; grid-template-columns:minmax(180px,.75fr) minmax(220px,1.25fr); align-items:center; gap:12px; padding:13px; border:1px solid var(--quiz-line); border-radius:14px; background:rgba(3,10,24,.42); }
.match-row label { color:#e2e8f0; font-weight:800; }
.match-row select,.numeric-field input { width:100%; min-height:48px; padding:0 12px; border:1px solid rgba(148,163,184,.24); border-radius:11px; background:#030a18; color:#f8fafc; }
.match-row select:focus,.numeric-field input:focus { border-color:rgba(103,232,249,.65); outline:3px solid rgba(103,232,249,.12); }
.match-row.is-correct { border-color:rgba(52,211,153,.5); background:rgba(52,211,153,.07); }
.match-row.is-wrong { border-color:rgba(248,113,113,.5); background:rgba(248,113,113,.06); }
.match-row>div { min-width:0; }
.match-correction { display:grid; grid-template-columns:auto minmax(0,1fr); gap:4px 10px; margin-top:8px; padding:9px 11px; border:1px solid rgba(52,211,153,.35); border-radius:10px; background:rgba(52,211,153,.09); }
.match-correction span { color:#6ee7b7; font-size:.65rem; font-weight:900; letter-spacing:.04em; text-transform:uppercase; }
.match-correction strong { grid-column:1/-1; color:#ecfdf5; font-size:.78rem; line-height:1.45; }
.numeric-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(190px,1fr)); gap:12px; }
.numeric-field { display:grid; gap:7px; }
.numeric-field>span { color:#dbeafe; font-size:.78rem; font-weight:850; }
.numeric-input { position:relative; }
.numeric-input input { padding-right:58px; font-size:1rem; }
.numeric-input small { position:absolute; right:13px; top:50%; transform:translateY(-50%); color:#8ea0b8; font-size:.72rem; font-weight:900; pointer-events:none; }
.answer-form.is-locked { pointer-events:none; opacity:.86; }
.feedback { margin:0 clamp(18px,4vw,32px) 26px; padding:17px 18px; border:1px solid; border-radius:15px; }
.feedback strong { display:block; margin-bottom:5px; }
.feedback p { color:#d8e1ed; line-height:1.62; }
.feedback .correct-answer { display:grid; gap:4px; margin:10px 0 12px; padding:12px 14px; border:1px solid rgba(52,211,153,.4); border-radius:11px; background:rgba(52,211,153,.1); color:#f8fafc; }
.feedback .correct-answer small { color:#6ee7b7; font-size:.65rem; font-weight:900; letter-spacing:.08em; text-transform:uppercase; }
.feedback .correct-answer b { color:#ecfdf5; line-height:1.55; }
.choice-explanations { display:grid; gap:9px; margin-top:16px; }
.choice-explanations h3 { color:#f8fafc; font-size:.92rem; }
.choice-explanations article { padding:12px 13px; border:1px solid var(--quiz-line); border-radius:11px; background:rgba(2,8,23,.35); }
.choice-explanations article.is-correct { border-color:rgba(52,211,153,.3); }
.choice-explanations article.is-wrong { border-color:rgba(248,113,113,.34); }
.choice-explanations header { display:flex; align-items:center; gap:8px; margin-bottom:5px; }
.choice-explanations header span { display:grid; place-items:center; width:21px; height:21px; border-radius:50%; background:rgba(148,163,184,.12); font-weight:900; }
.choice-explanations article.is-correct header span { color:#6ee7b7; }
.choice-explanations article.is-wrong header span { color:#fda4af; }
.choice-explanations p { margin:2px 0; font-size:.78rem; }
.choice-explanations small { display:block; margin-top:7px; color:#b9c7d8; font-size:.76rem; line-height:1.55; }
.feedback.success { border-color:rgba(52,211,153,.48); background:rgba(52,211,153,.09); }
.feedback.success strong { color:#6ee7b7; }
.feedback.error { border-color:rgba(248,113,113,.5); background:rgba(248,113,113,.08); }
.feedback.error>strong { color:#fda4af; }
.question-actions { display:flex; justify-content:space-between; gap:10px; padding:17px clamp(18px,4vw,30px); border-top:1px solid var(--quiz-line); background:rgba(3,9,20,.35); }
.button { min-height:45px; padding:10px 16px; border:1px solid var(--quiz-line); border-radius:12px; color:#eff6ff; font-weight:850; cursor:pointer; transition:transform .15s,border-color .15s,background .15s; }
.button:hover:not(:disabled) { transform:translateY(-2px); }
.button:disabled { opacity:.38; cursor:not-allowed; }
.button--secondary { background:rgba(148,163,184,.06); }
.button--secondary:hover:not(:disabled) { border-color:rgba(103,232,249,.4); }
.button--primary { margin-left:auto; border-color:rgba(103,232,249,.45); background:linear-gradient(135deg,#0891b2,#4f46e5); }
.scope-panel { position:sticky; top:98px; overflow:hidden; }
.scope-panel>header { padding:17px 18px; border-bottom:1px solid var(--quiz-line); }
.scope-panel>header p { margin-top:3px; font-size:.75rem; }
.scope-screen { margin:16px; overflow:hidden; border:1px solid rgba(103,232,249,.2); border-radius:15px; background:#020815; }
.scope-screen svg { display:block; width:100%; height:auto; }
.scope-grid-minor { stroke:rgba(148,163,184,.12); stroke-width:1; }
.scope-grid-major { stroke:rgba(148,163,184,.28); stroke-width:1.4; }
.scope-zero { stroke:rgba(248,250,252,.55); stroke-width:2; }
.scope-trace { fill:none; stroke:#67e8f9; stroke-width:4; stroke-linejoin:round; filter:drop-shadow(0 0 5px rgba(103,232,249,.55)); }
.scope-label { fill:#9fb0c6; font:700 16px ui-monospace,monospace; }
.scope-data { display:grid; grid-template-columns:1fr 1fr; gap:8px; padding:0 16px 17px; }
.scope-data span { padding:9px 10px; border:1px solid var(--quiz-line); border-radius:10px; color:#aebcd0; font-size:.69rem; }
.scope-data strong { display:block; color:#f8fafc; font-size:.78rem; }
.results-card { padding:clamp(26px,5vw,48px); text-align:center; }
.results-card h2 { margin-top:5px; font-size:clamp(1.7rem,4vw,2.7rem); }
.results-score { display:flex; justify-content:center; align-items:baseline; gap:7px; margin:24px 0 8px; }
.results-score strong { color:var(--quiz-cyan); font-size:4rem; line-height:1; }
.results-list { display:grid; grid-template-columns:repeat(auto-fit,minmax(180px,1fr)); gap:8px; margin:28px 0; text-align:left; }
.result-row { display:flex; align-items:center; gap:9px; padding:11px; border:1px solid var(--quiz-line); border-radius:11px; background:rgba(3,10,24,.4); color:#cbd5e1; font-size:.74rem; }
.result-row i { width:22px; height:22px; display:grid; place-items:center; flex:0 0 auto; border-radius:50%; font-style:normal; font-weight:900; }
.result-row.correct i { background:rgba(52,211,153,.14); color:#6ee7b7; }
.result-row.wrong i { background:rgba(248,113,113,.14); color:#fda4af; }
.results-actions { display:flex; justify-content:center; gap:10px; }
@media(max-width:900px){.basics-hero{grid-template-columns:1fr}.hero-signal{display:none}.quiz-layout.has-scope{grid-template-columns:1fr}.scope-panel{position:relative;top:auto;grid-row:1}.scope-screen{max-width:620px;margin-inline:auto}.scope-data{max-width:620px;margin-inline:auto}}
@media(max-width:620px){.basics-shell{width:min(100% - 16px,1120px);padding-top:68px;padding-bottom:calc(34px + env(safe-area-inset-bottom))}.basics-hero{min-height:auto;padding:30px 20px;border-radius:22px}.quiz-status{top:6px;padding:12px}.status-copy{display:grid;gap:2px}.status-copy strong{font-size:.84rem}.status-score{gap:8px;font-size:.65rem}.question-card,.scope-panel,.results-card{border-radius:18px}.match-row{grid-template-columns:1fr}.question-actions{position:sticky;bottom:0;z-index:5;display:grid;grid-template-columns:auto 1fr;padding-bottom:calc(13px + env(safe-area-inset-bottom));background:rgba(7,13,25,.97)}.question-actions .button{min-width:0;padding-inline:11px}.button--primary{margin-left:0}.scope-data{grid-template-columns:1fr 1fr}.results-actions{flex-direction:column}.results-actions .button{width:100%}}
@media(prefers-reduced-motion:reduce){.progress-track span{transition:none}}