:root{color-scheme:light dark;--bg: #0f1115;--surface: #1a1d24;--surface-2: #22262f;--text: #f2f4f8;--muted: #a7b0c0;--accent: #5b8cff;--accent-2: #3d6fe6;--ok: #3dd68c;--bad: #ff6b6b;--border: #2e3440;font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,Noto Sans,sans-serif}@media(prefers-color-scheme:light){:root{--bg: #f6f7fb;--surface: #ffffff;--surface-2: #eef1f7;--text: #12151c;--muted: #5c6575;--border: #dde2ec}}*{box-sizing:border-box}body{margin:0;min-height:100dvh;background:var(--bg);color:var(--text)}#root{min-height:100dvh}.screen{max-width:480px;margin:0 auto;padding:12px 14px 24px;min-height:100dvh;display:flex;flex-direction:column;gap:12px}.header{padding:8px 0 4px}.title{margin:0;font-size:1.35rem;letter-spacing:-.02em}.subtitle{margin:6px 0 0;color:var(--muted);font-size:.95rem}.card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:16px;display:flex;flex-direction:column;gap:12px}.field-label{font-size:.85rem;color:var(--muted)}.field-label.spaced{margin-top:8px}.select-like{padding:12px 14px;border-radius:10px;background:var(--surface-2);border:1px solid var(--border);font-weight:600}.radio-group{display:flex;flex-direction:column;gap:8px}.radio-row{display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:10px;border:1px solid var(--border);background:var(--surface-2);cursor:pointer}.radio-row input{accent-color:var(--accent)}.topbar{display:flex;align-items:center;gap:8px;padding:4px 0 8px}.topbar-title{flex:1;text-align:center;font-weight:600;font-size:.95rem}.topbar-spacer{width:40px}.list{display:flex;flex-direction:column;gap:10px;flex:1}.topic-card{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:14px;border-radius:14px;border:1px solid var(--border);background:var(--surface)}.topic-meta{font-weight:600}.topic-desc{margin:4px 0 0;color:var(--muted);font-size:.9rem}.topic-count{margin-top:6px;font-size:.85rem;color:var(--muted)}.footer-card{margin-top:auto;padding:14px;border-radius:14px;border:1px solid var(--border);background:var(--surface);display:flex;flex-direction:column;gap:10px}.session-line{font-size:.95rem;color:var(--muted)}.btn-row{display:flex;flex-direction:column;gap:8px}.btn{border:none;border-radius:10px;padding:10px 14px;font-weight:600;cursor:pointer;font-size:.95rem}.btn.full{width:100%}.btn.primary{background:linear-gradient(180deg,var(--accent),var(--accent-2));color:#fff}.btn.secondary{background:var(--surface-2);color:var(--text);border:1px solid var(--border)}.btn.ghost{background:transparent;color:var(--text);width:40px}.exercise-card .prompt{margin:0;color:var(--muted);font-size:.9rem}.sentence{font-size:1.15rem;line-height:1.45;font-weight:600}.blank{display:inline-block;min-width:4.5ch;margin:0 4px;padding:0 4px 2px;border-bottom:2px dashed var(--muted);color:var(--muted);letter-spacing:.08em}.hints{display:flex;flex-direction:column;gap:6px;font-size:.92rem}.hint-label{color:var(--muted);margin-right:6px}.input{width:100%;padding:12px 14px;border-radius:10px;border:1px solid var(--border);background:var(--surface-2);color:var(--text);font-size:1rem}.feedback{display:flex;flex-direction:column;gap:10px}.feedback-ok{color:var(--ok);font-weight:700;font-size:1.1rem}.feedback-bad{color:var(--bad);font-weight:700;font-size:1.1rem}.expected{margin:0}.note{margin:0;color:var(--muted);font-size:.9rem}.section-title{margin:0;font-size:1rem}.section-title.spaced{margin-top:8px}.stats{margin:0;padding-left:18px;color:var(--muted);line-height:1.5}code{font-size:.85em;background:var(--surface-2);padding:2px 6px;border-radius:6px}