:root{--bg: #020617;--bg-panel: #0f172a;--bg-card: #111827;--bg-hover: #1e293b;--border: #1e293b;--sky: #38bdf8;--purple: #a78bfa;--orange: #fb923c;--green: #34d399;--red: #f87171;--amber: #fbbf24;--text-main: #e2e8f0;--text-sub: #94a3b8;--text-muted: #475569;--radius-lg: 1rem;--radius-md: .75rem}*{box-sizing:border-box}html,body{margin:0;padding:0;background:var(--bg);color:var(--text-main);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;min-height:100vh}#app{max-width:32rem;margin:0 auto;min-height:100vh;display:flex;flex-direction:column;padding:1.25rem 1rem 3rem}h1,h2,h3{margin:0 0 .25rem}.subtitle{color:var(--text-sub);font-size:.9rem;margin-bottom:1.5rem}.card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:1.25rem;margin-bottom:1rem;transition:border-color .15s ease,transform .15s 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ease}.option-btn:hover:not(.locked){border-color:var(--sky)}.option-btn.selected{border-color:var(--sky);background:#38bdf81a}.option-btn.correct{border-color:var(--green);background:#34d3991f}.option-btn.incorrect{border-color:var(--red);background:#f871711f}.option-btn.locked{cursor:default}.matching-grid{display:grid;grid-template-columns:1fr 1fr;gap:.6rem;margin-bottom:1rem}.matching-col-label{font-size:.75rem;text-transform:uppercase;letter-spacing:.04em;color:var(--text-sub);margin-bottom:.4rem}.match-item{display:block;width:100%;text-align:left;background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-md);color:var(--text-main);padding:.6rem .75rem;margin-bottom:.5rem;cursor:pointer;font-size:.85rem;transition:border-color .15s ease,background .15s ease,opacity .15s ease}.match-item:hover:not(.matched):not(.locked){border-color:var(--sky)}.match-item.active-select{border-color:var(--sky);background:#38bdf81f}.match-item.matched{opacity:.55;cursor:default}.match-item.correct{border-color:var(--green);background:#34d3991f;opacity:1}.match-item.incorrect{border-color:var(--red);background:#f871711f;opacity:1}.match-pair-color-0{box-shadow:inset 3px 0 0 var(--sky)}.match-pair-color-1{box-shadow:inset 3px 0 0 var(--purple)}.match-pair-color-2{box-shadow:inset 3px 0 0 var(--orange)}.match-pair-color-3{box-shadow:inset 3px 0 0 var(--green)}.match-pair-color-4{box-shadow:inset 3px 0 #f472b6}.match-pair-color-5{box-shadow:inset 3px 0 #facc15}.explanation-box{background:#fbbf241a;border:1px solid rgba(251,191,36,.35);border-radius:var(--radius-md);padding:.85rem 1rem;font-size:.88rem;line-height:1.45;color:var(--text-main);margin:1rem 0}.explanation-box strong{color:var(--amber)}.search-input,.text-input{width:100%;background:var(--bg-card);border:1px solid 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summary{cursor:pointer;color:var(--sky);font-size:.85rem;-webkit-user-select:none;user-select:none}.disclosure[open] summary{margin-bottom:.5rem}.result-score{text-align:center;margin:1.5rem 0}.result-percent{font-size:3.5rem;font-weight:700;line-height:1}.result-percent.great{color:var(--green)}.result-percent.ok{color:var(--amber)}.result-percent.poor{color:var(--red)}.result-label{font-size:1.1rem;color:var(--text-sub);margin-top:.4rem}.breakdown-row{margin-bottom:.85rem}.breakdown-row-head{display:flex;justify-content:space-between;font-size:.85rem;margin-bottom:.3rem;color:var(--text-sub)}.empty-state{text-align:center;color:var(--text-sub);padding:2rem 1rem;font-size:.9rem}@media (max-width: 420px){.matching-grid{grid-template-columns:1fr}}