:root{--bg:#f6f7f9;--surface:#fff;--text:#1b1f24;--muted:#5b6470;--border:#d9dee5;--primary:#1f6feb;--primary-text:#fff;--danger:#c62828;--radius:12px;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light dark}@media (prefers-color-scheme:dark){:root{--lightningcss-light: ;--lightningcss-dark:initial;--bg:#101317;--surface:#1a1f25;--text:#e8ebef;--muted:#9aa4b0;--border:#2e353e;--primary:#4a8dff;--danger:#ff6b6b}}*{box-sizing:border-box}body{background:var(--bg);color:var(--text);-webkit-text-size-adjust:100%;margin:0;font-family:system-ui,-apple-system,Hiragino Sans,Noto Sans JP,sans-serif;font-size:16px;line-height:1.6}.page{padding:16px;padding-bottom:calc(16px + env(safe-area-inset-bottom))}.narrow{max-width:640px;margin:0 auto}.stack{flex-direction:column;gap:16px;display:flex}.row{align-items:center;gap:8px;display:flex}.between{justify-content:space-between}.title{margin:8px 0;font-size:1.3rem}h2{margin:0;font-size:1.1rem}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:16px}.field{flex-direction:column;gap:4px;display:flex}.field input{border:1px solid var(--border);background:var(--bg);color:var(--text);border-radius:8px;padding:12px;font-size:16px}.btn{border-radius:var(--radius);border:1px solid var(--border);background:var(--surface);min-height:48px;color:var(--text);cursor:pointer;padding:12px 16px;font-size:1rem}.btn.primary{background:var(--primary);border-color:var(--primary);color:var(--primary-text);font-weight:600}.btn:disabled{opacity:.5;cursor:default}.badge{background:var(--primary);color:var(--primary-text);border-radius:999px;padding:2px 8px;font-size:.8rem}.list{margin:0;padding-left:1.2em}.muted{color:var(--muted)}.small{font-size:.85rem}.wide{max-width:960px;margin:0 auto}.wrap{flex-wrap:wrap}.stack-sm{flex-direction:column;gap:6px;display:flex}.topnav{background:var(--surface);border-bottom:1px solid var(--border);gap:4px;padding:8px 16px;display:flex;overflow-x:auto}.topnav a{color:var(--text);white-space:nowrap;border-radius:8px;padding:8px 12px;text-decoration:none}.topnav a.active{background:var(--primary);color:var(--primary-text)}select,.field select{border:1px solid var(--border);background:var(--bg);color:var(--text);border-radius:8px;padding:10px;font-size:16px}.table{border-collapse:collapse;width:100%;font-size:.9rem}.table th,.table td{text-align:left;border-bottom:1px solid var(--border);vertical-align:top;padding:8px 6px}.meter{background:var(--border);border-radius:999px;height:10px;overflow:hidden}.meter-fill{background:var(--primary);height:100%}.badge.subtle{background:var(--border);color:var(--text)}.item-title{margin:0;font-size:1rem}.passage,.stem{white-space:pre-wrap;margin:0}.choices{margin:0;padding-left:1.6em}.choices .correct{color:var(--primary);font-weight:700}.checks{grid-template-columns:max-content 1fr;gap:4px 12px;margin:0;display:grid}.checks dt{color:var(--muted)}.checks dd{margin:0}.explanation{background:var(--bg);border-radius:8px;margin:0;padding:8px 12px;font-size:.9rem}.error{color:var(--danger)}