:root{--bg: #0f172a;--panel: #1e293b;--panel-2: #334155;--line: #475569;--line-strong: #94a3b8;--text: #e2e8f0;--muted: #94a3b8;--given: #f8fafc;--user: #60a5fa;--accent: #6366f1;--selected: #3b4a68;--peer: #273449;--same: #2d3f5f;--error-bg: #7f1d1d;--error-text: #fecaca;--ok: #22c55e}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}.app{max-width:520px;margin:0 auto;padding:16px;display:flex;flex-direction:column;gap:16px}.app-header{display:flex;align-items:center;justify-content:space-between}.app-header h1{font-size:1.5rem;margin:0;background:linear-gradient(90deg,#818cf8,#22d3ee);-webkit-background-clip:text;background-clip:text;color:transparent}.reset-campaign{background:var(--panel);color:var(--muted);border:1px solid var(--line);border-radius:8px;padding:6px 12px;cursor:pointer;font-size:.8rem}.reset-campaign:hover{color:var(--text);border-color:var(--line-strong)}.status-bar{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.stat{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:8px;text-align:center;display:flex;flex-direction:column;gap:2px}.stat-label{font-size:.65rem;text-transform:uppercase;letter-spacing:.05em;color:var(--muted)}.stat-value{font-size:.95rem;font-weight:600}.board{display:grid;grid-template-columns:repeat(9,1fr);aspect-ratio:1;background:var(--line);border:3px solid var(--line-strong);border-radius:8px;overflow:hidden;gap:1px}.cell{position:relative;background:var(--panel);border:none;color:var(--user);font-size:clamp(1rem,5vw,1.6rem);font-weight:600;cursor:pointer;display:flex;align-items:center;justify-content:center;aspect-ratio:1;padding:0;transition:background .1s}.cell.given{color:var(--given)}.cell.peer{background:var(--peer)}.cell.same-value{background:var(--same)}.cell.selected{background:var(--selected);box-shadow:inset 0 0 0 2px var(--accent)}.cell.error{background:var(--error-bg);color:var(--error-text)}.cell.box-right{border-right:3px solid var(--line-strong)}.cell.box-bottom{border-bottom:3px solid var(--line-strong)}.notes{display:grid;grid-template-columns:repeat(3,1fr);width:100%;height:100%;padding:2px}.note{font-size:.5rem;line-height:1;color:var(--muted);display:flex;align-items:center;justify-content:center}.explanation{background:var(--error-bg);color:var(--error-text);border:1px solid #b91c1c;border-radius:10px;padding:10px 14px;font-size:.85rem;line-height:1.4}.number-pad{display:grid;grid-template-columns:repeat(5,1fr);gap:8px}.pad-key{background:var(--panel-2);color:var(--text);border:1px solid var(--line);border-radius:10px;padding:14px 0;font-size:1.3rem;font-weight:600;cursor:pointer}.pad-key:hover:not(:disabled){background:var(--selected)}.pad-key:disabled{opacity:.35;cursor:default}.pad-key.notes{color:var(--accent)}.pad-key.erase{color:var(--muted)}.controls{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.ctrl{background:var(--panel);color:var(--text);border:1px solid var(--line);border-radius:10px;padding:10px 4px;font-size:.8rem;cursor:pointer}.ctrl:hover{border-color:var(--line-strong)}.ctrl.active{background:var(--accent);border-color:var(--accent);color:#fff}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#020617bf;display:flex;align-items:center;justify-content:center;padding:16px;z-index:10}.modal{background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:24px;max-width:360px;width:100%;text-align:center}.modal h2{margin:0 0 16px}.modal-stats{list-style:none;margin:0 0 16px;padding:0;display:flex;flex-direction:column;gap:8px}.modal-stats li{display:flex;justify-content:space-between;padding:6px 10px;background:var(--bg);border-radius:8px;font-size:.9rem}.modal-stats li.highlight{color:var(--ok);font-weight:700}.next-hint{color:var(--muted);font-size:.85rem;margin:0 0 16px}.next-btn{width:100%;background:var(--accent);color:#fff;border:none;border-radius:10px;padding:14px;font-size:1rem;font-weight:600;cursor:pointer}.next-btn:hover{background:#4f46e5}.update-toast{position:fixed;left:50%;bottom:20px;transform:translate(-50%);display:flex;align-items:center;gap:14px;background:var(--panel);color:var(--text);border:1px solid var(--line-strong);border-radius:12px;padding:12px 16px;box-shadow:0 8px 24px #02061780;z-index:20;font-size:.9rem;max-width:calc(100% - 32px)}.update-actions{display:flex;align-items:center;gap:8px}.update-btn{background:var(--accent);color:#fff;border:none;border-radius:8px;padding:8px 14px;font-weight:600;cursor:pointer}.update-btn:hover{background:#4f46e5}.update-dismiss{background:transparent;color:var(--muted);border:none;font-size:1rem;cursor:pointer;padding:4px 6px}.update-dismiss:hover{color:var(--text)}