:root{--color-text: #172033;--color-muted: #4f5b73;--color-surface: #ffffff;--color-border: #b9c1d1;--color-primary: #225c55;--color-primary-hover: #174740;--color-focus: #f4b740;--color-success: #2f7d32;--color-success-bg: #eff8f0;--color-error: #b23b3b;--color-error-bg: #fff1f1;color:#172033;background:#f7f8fb;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-synthesis:none;line-height:1.5;text-rendering:optimizeLegibility}*{box-sizing:border-box}body{min-width:320px;min-height:100vh;margin:0;background:linear-gradient(180deg,#eef4f7,#f7f8fb 280px),#f7f8fb}button,input,select,textarea{font:inherit}a{color:inherit}button,input,a{-webkit-tap-highlight-color:transparent}:focus-visible{outline:3px solid var(--color-focus);outline-offset:3px}.app-shell{width:min(100% - 32px,960px);margin:0 auto;padding:48px 0}.intro{max-width:560px}.intro h1{margin:0 0 12px;color:#243b6b;font-size:2.35rem;font-weight:700;letter-spacing:0;line-height:1.1}.intro p{margin:0 0 24px;color:#4f5b73}.game-panel{max-width:720px}.game-panel h1{margin:0 0 28px;color:var(--color-text);font-size:2.15rem;line-height:1.2;letter-spacing:0}.eyebrow{margin:0 0 8px;color:#58657d;font-size:.9rem;font-weight:700;text-transform:uppercase}.answer-form{display:grid;grid-template-columns:1fr auto;gap:10px 12px;align-items:end;margin-bottom:24px}.answer-form label{grid-column:1 / -1;color:#39465e;font-weight:700}.answer-form input{min-width:0;min-height:56px;border:1px solid var(--color-border);border-radius:8px;padding:14px 16px;background:var(--color-surface);color:var(--color-text);font-size:1.1rem}.answer-form input:disabled{background:#edf0f5;color:#58657d;opacity:1}.answer-form input[aria-invalid=true]{border-color:var(--color-error)}.field-help{grid-column:1 / -1;margin:-2px 0 0;color:var(--color-muted);font-size:.95rem}.primary-action,.secondary-action{min-height:48px;border:1px solid transparent;border-radius:8px;padding:11px 18px;font-weight:700;cursor:pointer;transition:background-color .12s ease,border-color .12s ease,color .12s ease}.primary-action{background:var(--color-primary);color:#fff}.primary-action:hover:not(:disabled){background:var(--color-primary-hover)}.secondary-action{display:inline-flex;align-items:center;justify-content:center;background:var(--color-surface);border-color:var(--color-border);color:#243047;text-decoration:none}.secondary-action:hover:not(:disabled){border-color:#77849b;background:#f3f6fa}.primary-action:disabled,.secondary-action:disabled{cursor:not-allowed;opacity:.55}.feedback{border-left:4px solid;border-radius:8px;margin:0 0 20px;padding:14px 16px;background:var(--color-surface)}.feedback h2{margin:0 0 6px;font-size:1rem}.feedback p{margin:0;color:#39465e}.feedback.is-correct{border-color:var(--color-success);background:var(--color-success-bg)}.feedback.is-incorrect{border-color:var(--color-error);background:var(--color-error-bg)}.score{margin:0 0 24px;color:#39465e;font-size:1.1rem}.history-panel{max-width:560px;margin-top:36px}.history-panel h2,.result-detail h2{margin:0 0 10px;color:#243047;font-size:1.25rem}.history-panel p,.result-detail p{margin:0 0 14px;color:#39465e}.session-history,.failed-list{margin:0;padding-left:22px}.session-history li{margin-bottom:10px;color:#39465e}.session-history span:first-child{display:inline-block;min-width:52px;color:#172033;font-weight:700}.result-detail{margin-bottom:24px}.failed-list li{margin-bottom:18px;padding-bottom:18px;border-bottom:1px solid #d9dee8}.failed-list dl{display:grid;gap:8px;margin:0}.failed-list dt{color:#58657d;font-size:.85rem;font-weight:700;text-transform:uppercase}.failed-list dd{margin:2px 0 0;color:#172033;overflow-wrap:anywhere}.actions{display:flex;flex-wrap:wrap;gap:12px}@media(min-width:760px){.app-shell{padding:64px 0}.history-panel{margin-top:48px}}@media(max-width:640px){.app-shell{width:min(100% - 24px,960px);padding:32px 0}.answer-form{grid-template-columns:1fr}.intro h1,.game-panel h1{font-size:1.85rem}.primary-action,.secondary-action{width:100%}}