:root{--bg:#f7f7f9;--card:#ffffff;--border:#e5e7eb;--text:#0b1220;--muted:#6b7280;--primary:#2563eb;--accent:#10b981;--warn:#f59e0b;--radius:12px;--shadow:0 8px 24px rgba(2, 6, 23, 0.06)}*{box-sizing:border-box}html,body{height:100%}body{margin:0;font-family:ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Apple Color Emoji","Segoe UI Emoji";color:var(--text);background:var(--bg);line-height:1.55}.container{max-width:960px;margin:0 auto;padding:24px}header{margin-bottom:20px;text-align:center}h1{margin:0 0 8px 0;font-size:28px;letter-spacing:-.02em;background:linear-gradient(90deg,var(--accent),var(--primary));-webkit-background-clip:text;background-clip:text;color:#fff0}.subtle{color:var(--muted);font-size:14px}.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px}.controls{display:flex;flex-wrap:wrap;gap:12px;align-items:center;margin-bottom:16px}.control{display:flex;align-items:center;gap:8px}label{font-size:14px;color:var(--muted)}select,button{appearance:none;border:1px solid var(--border);background:#fff;color:var(--text);border-radius:10px;font-size:14px;padding:10px 12px;transition:border-color .15s ease,box-shadow .15s ease,transform .04s ease}select:focus,button:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 4px rgb(37 99 235 / .15)}.btn{background:var(--primary);color:#fff;border:none;cursor:pointer;font-weight:600}.btn:hover{transform:translateY(-1px)}.btn:active{transform:translateY(0)}.btn-secondary{background:#fff;color:var(--text);border:1px solid var(--border);font-weight:600}.btn-success{background:var(--accent);color:#fff;border:none;cursor:pointer;font-weight:600}.btn-success:hover{transform:translateY(-1px)}.btn-success:active{transform:translateY(0)}.btn-success:focus{outline:none;border-color:#fff0;box-shadow:0 0 0 4px rgb(16 185 129 / .2)}.grid{display:grid;grid-template-columns:1fr;gap:12px}@media (min-width:720px){.grid{grid-template-columns:repeat(3,1fr)}}.stat{border:1px solid var(--border);border-radius:12px;padding:14px;display:flex;flex-direction:column;gap:6px;background:#fff}.stat-label{font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.06em}.stat-value{font-size:24px;font-weight:700;letter-spacing:-.02em}.hz{color:var(--accent)}.progress{position:relative;height:8px;background:#f1f3f5;border-radius:8px;overflow:hidden;border:1px solid var(--border)}.bar{position:absolute;left:0;top:0;bottom:0;width:0%;background:var(--primary);transition:width .2s ease}.canvas-wrap{border:1px dashed var(--border);border-radius:12px;padding:10px;background:#fff}canvas{width:100%;height:140px;display:block}#playground{width:100%;height:180px;display:block}.row{display:grid;grid-template-columns:1fr;gap:12px}@media (min-width:720px){.row{grid-template-columns:1.2fr .8fr}}.hint{background:#fff;border:1px solid var(--border);border-radius:12px;padding:12px;color:var(--muted);font-size:14px}.hint strong{color:var(--text)}.pill{display:inline-block;padding:4px 8px;border-radius:999px;border:1px solid var(--border);background:#fff;font-size:12px;color:var(--muted)}.pill.warn{border-color:var(--warn);color:var(--warn)}footer{margin-top:16px;color:var(--muted);font-size:12px;text-align:center}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}input[type="number"]{appearance:textfield;border:1px solid var(--border);background:#fff;color:var(--text);border-radius:10px;font-size:14px;padding:10px 12px;transition:border-color .15s ease,box-shadow .15s ease,transform .04s ease;width:100px}input[type="number"]:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 4px rgb(37 99 235 / .15)}.gradient-text{font-size:2.5rem;font-weight:700;text-align:center;background:linear-gradient(90deg,#007cf0,#00dfd8);-webkit-background-clip:text;-webkit-text-fill-color:#fff0;background-clip:text;color:#fff0;margin-bottom:10px}