:root{--bg:#0c1420;--panel:#111b2a;--border:#1b2a3d;--ink:#e7f2ff;--muted:#9ec7ff;--accent:#76beff;--danger:#ff7a85;--good:#7affb3}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;background:linear-gradient(180deg,#0c1420,#0a1018);color:var(--ink);font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Inter,Arial,sans-serif;}
.topbar{display:flex;align-items:center;justify-content:space-between;padding:10px 14px;background:linear-gradient(180deg,#0e1828,#0c1420);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:10}
.topbar .back{color:var(--muted);text-decoration:none;border:1px solid var(--border);padding:6px 10px;border-radius:8px;background:#0a121d}
.topbar .logo{margin:0;font-size:18px;letter-spacing:.5px}
.topbar .stats{display:flex;gap:12px;align-items:center}
.topbar .stats>div{background:#0a121d;border:1px solid var(--border);border-radius:8px;padding:6px 10px;color:var(--muted)}
.wrap{display:grid;grid-template-columns:220px 1fr;gap:14px;padding:14px;max-width:1400px;margin:0 auto}
.toolbar{display:flex;flex-direction:column;gap:8px;background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:10px;position:sticky;top:64px;height:calc(100vh - 94px);overflow:auto}
.toolbar .tw{background:#0e1828;color:var(--ink);border:1px solid var(--border);border-radius:10px;padding:8px 10px;cursor:pointer;text-align:center;font-weight:700;}
.toolbar .tw.small{font-size:12px}
.toolbar .tw.locked{opacity:.45}
.toolbar .tw.tool{background:#1a2434}
.stage{background:#0a121d;border:1px solid var(--border);border-radius:14px;overflow:hidden;position:relative}
#game{display:block;width:100%;height:auto;background:linear-gradient(180deg,#0b1524,#0b1422)}

/* Overlays */
.overlay{position:fixed;inset:0;background:rgba(5,10,16,.6);backdrop-filter:blur(5px);display:flex;align-items:center;justify-content:center;z-index:20}
.overlay.hidden{display:none}
.panel{background:linear-gradient(180deg,#0f1a2b,#0d1726);border:1px solid var(--border);border-radius:12px;box-shadow:0 18px 60px rgba(0,0,0,.45);padding:18px;min-width:320px;max-width:min(760px,90vw)}
.panel.grid{max-width:min(740px,92vw)}
.panel h2,.panel h3{margin:6px 0 10px 0}
.panel .howto{opacity:.9;line-height:1.5}
.panel .actions{display:flex;gap:10px;margin-top:12px}
.panel button{background:#0e1828;color:var(--ink);border:1px solid var(--border);border-radius:10px;padding:10px 12px;font-weight:800;cursor:pointer}
.panel .best{margin-top:8px;color:var(--muted)}
.lv-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:8px}
.lv-grid button{padding:10px;border-radius:10px;border:1px solid var(--border);background:#0e1828;color:var(--ink);font-weight:800;cursor:pointer}
.lv-grid button.locked{opacity:.45}
.lv-grid button.done{border-color:var(--good)}

/* Simple in-canvas sprite helpers (for reference) */
@keyframes bob{0%{transform:translateY(0)}50%{transform:translateY(-2px)}100%{transform:translateY(0)}}
@keyframes blink{0%,90%,100%{opacity:1}95%{opacity:.2}}

/* Mobile tweaks */
@media (max-width:900px){
  .wrap{grid-template-columns:1fr}
  .toolbar{flex-direction:row;top:56px;height:auto;position:sticky;overflow:auto}
  .toolbar .tw{min-width:86px}
}