:root{color-scheme:light;--ink: #19213a;--muted: #657089;--line: #d9e0ec;--surface: #f4f7fb;--panel: #ffffff;--accent: #3157d5;--accent-strong: #1c328f;--teal: #0f766e;--warm: #a15c13;--danger: #b33434;--shadow: 0 18px 52px rgba(25, 33, 58, .12);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--surface)}button{min-width:96px;border:1px solid var(--line);border-radius:8px;padding:11px 16px;background:var(--panel);color:var(--ink);font:inherit;font-weight:650;cursor:pointer}select{max-width:220px;border:1px solid var(--line);border-radius:8px;padding:10px 34px 10px 12px;background:var(--panel);color:var(--ink);font:inherit;font-weight:650}button:disabled{cursor:not-allowed;opacity:.45}button.primary{border-color:var(--accent);background:var(--accent);color:#fff}.shell{min-height:100vh;padding:32px}.workspace{width:min(1120px,100%);margin:0 auto}.topbar{display:flex;align-items:end;justify-content:space-between;gap:24px;margin-bottom:20px}.eyebrow{margin:0 0 6px;color:var(--accent);font-size:13px;font-weight:750;text-transform:uppercase}h1,h2,p{margin:0}h1{font-size:32px;line-height:1.15;letter-spacing:0}h2{font-size:15px;line-height:1.3}.status-pill{min-width:116px;border:1px solid var(--line);border-radius:999px;padding:8px 13px;background:var(--panel);color:var(--muted);font-size:13px;font-weight:700;text-align:center}.practice-panel,.recorder-panel,.result-panel{border:1px solid var(--line);border-radius:8px;background:var(--panel);box-shadow:var(--shadow)}.practice-panel{padding:24px}.panel-heading{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:16px;color:var(--muted)}.example-count{display:block;margin-top:4px;font-size:12px;font-weight:750}.example-actions{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px}.lesson-brief{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(280px,.7fr);gap:18px;margin-bottom:16px}.lesson-main,.lesson-rationale,.listen-guide{border:1px solid var(--line);border-radius:8px;background:#fbfcff}.lesson-main{padding:20px}.lesson-kicker{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:14px}.lesson-kicker span{border:1px solid #cbd6f6;border-radius:999px;padding:6px 10px;background:#eef3ff;color:var(--accent-strong);font-size:12px;font-weight:800}.lesson-main h2{margin-bottom:10px;color:var(--ink);font-size:24px;line-height:1.25}.lesson-main p,.lesson-rationale p,.listen-guide li{color:#3c475e;font-size:15px;line-height:1.75}.lesson-rationale{padding:18px;background:#fffaf2}.lesson-rationale span,.listen-guide span{display:block;margin-bottom:8px;color:var(--warm);font-size:12px;font-weight:850;text-transform:uppercase}.listen-guide{margin-bottom:16px;padding:18px 20px}.listen-guide ul{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;margin:0;padding:0;list-style:none}.listen-guide li{border-left:3px solid #92a7ef;padding:6px 0 6px 11px;background:#f7f9ff}.shadowing-player{display:grid;grid-template-columns:minmax(180px,1fr) minmax(260px,460px);align-items:center;gap:18px;border:1px solid #c9d5ff;border-radius:8px;padding:16px;background:linear-gradient(180deg,#f8fbff,#edf3ff)}.shadowing-player strong{display:block;margin-bottom:5px;font-size:17px;line-height:1.3}.shadowing-player span{color:var(--muted);font-size:13px;font-weight:700}.recorder-panel{display:grid;grid-template-columns:minmax(180px,1fr) auto minmax(220px,280px);align-items:center;gap:20px;margin-top:16px;padding:18px 20px}.meter{display:flex;align-items:center;gap:10px;color:var(--muted)}.meter span{width:12px;height:12px;border-radius:999px;background:#aab3af}.meter span.active{background:var(--danger);box-shadow:0 0 0 6px #a936361f}.controls{display:flex;flex-wrap:wrap;gap:10px}audio{width:100%;height:38px}.result-panel{margin-top:16px;padding:24px}.empty-state,.loading-state,.error-state{min-height:140px;display:grid;place-items:center;border:1px dashed var(--line);border-radius:8px;color:var(--muted);text-align:center}.error-state{color:var(--danger)}.feedback{display:grid;gap:14px}.feedback-block{border-top:1px solid var(--line);padding-top:14px}.feedback-block:first-child{border-top:0;padding-top:0}.feedback-block span{display:block;margin-bottom:8px;color:var(--muted);font-size:12px;font-weight:800;text-transform:uppercase}.feedback-block p,.feedback-block li{font-size:15px;line-height:1.7}.feedback-block code{display:block;overflow-x:auto;border-radius:8px;padding:12px;background:#f0f3fa;white-space:pre-wrap;line-height:1.6}.feedback-block ul{margin:0;padding-left:20px}.feedback-block em{color:var(--muted);font-style:normal}@media(max-width:760px){.shell{padding:20px}.topbar,.recorder-panel,.lesson-brief{display:flex;align-items:stretch;flex-direction:column}.status-pill{width:fit-content}.panel-heading,.example-actions{align-items:stretch;flex-direction:column}.example-actions{width:100%}.listen-guide ul{grid-template-columns:1fr}select{max-width:none;width:100%}.shadowing-player{grid-template-columns:1fr}button{flex:1 1 120px}}