:root{
  --bg:#0f1420; --panel:#161d2e; --panel2:#1c2438; --line:#2a3550;
  --accent:#4fd1c5; --accent2:#f6ad55; --danger:#f56565; --ok:#48bb78;
  --text:#e6ecf5; --muted:#8a97b3; --belt:#e2b04a; --slider:#9f7aea;
}
*{box-sizing:border-box;}
html,body{touch-action:manipulation;overscroll-behavior:none;}
body{margin:0;background:var(--bg);color:var(--text);font-family:'Segoe UI',system-ui,sans-serif;}
.wrap{max-width:840px;margin:0 auto;padding:14px;}

/* ---- header ---- */
.topbar{display:flex;align-items:center;gap:12px;margin-bottom:10px;}
.brand{font-size:19px;letter-spacing:.3px;}
.brand b{font-weight:700;}
.topbar .spacer{flex:1;}
.tabs{display:flex;gap:8px;}
.drawer-toggle{background:var(--panel2);border:1px solid var(--line);color:var(--text);
  padding:7px 12px;border-radius:8px;cursor:pointer;font-size:12.5px;transition:.15s;}
.drawer-toggle:hover{border-color:var(--accent);}
.drawer-toggle.active{background:var(--accent);color:#0b1220;font-weight:600;border-color:var(--accent);}

/* ---- drawers ---- */
.drawer{max-height:0;overflow:hidden;transition:max-height .28s ease;
  background:var(--panel);border-radius:10px;border:1px solid transparent;}
.drawer.open{max-height:460px;border-color:var(--line);margin-bottom:10px;}
.drawer-inner{padding:12px;}
.drawer-title{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.6px;margin-bottom:8px;}

/* level grid inside drawer */
.levels{display:flex;flex-direction:column;gap:10px;}
.chapter{display:flex;flex-direction:column;gap:5px;}
.chapter-name{font-size:10.5px;color:var(--muted);text-transform:uppercase;letter-spacing:.6px;}
.chapter-row{display:flex;gap:6px;flex-wrap:wrap;}
.lvlbtn{position:relative;width:40px;height:40px;padding:0;flex:0 0 auto;display:flex;flex-direction:column;
  align-items:center;justify-content:center;font-size:14px;border-radius:9px;line-height:1;cursor:pointer;
  background:var(--panel2);border:1px solid var(--line);color:var(--text);transition:.15s;}
.lvlbtn:hover{border-color:var(--accent);}
.lvlbtn.active{background:var(--accent);color:#0b1220;font-weight:700;}
.lvlbtn .st{font-size:8px;line-height:1;color:var(--accent2);height:8px;}
.lvlbtn.active .st{color:#0b1220;}
.lvlbtn.locked{opacity:.4;pointer-events:none;}

.guide-cols{display:grid;grid-template-columns:1fr 1fr;gap:16px;}
@media (max-width:640px){ .guide-cols{grid-template-columns:1fr;} }
.legend{display:flex;flex-direction:column;gap:6px;font-size:11.5px;color:var(--muted);}
.legend span{display:inline-flex;align-items:center;gap:6px;}
.swatch{width:11px;height:11px;border-radius:3px;flex:0 0 auto;}
.sensor-row{display:flex;align-items:center;gap:6px;font-size:12px;margin:3px 0;}
.dot{width:9px;height:9px;border-radius:50%;background:#3a4258;flex:0 0 auto;}
.dot.on{background:var(--ok);box-shadow:0 0 8px var(--ok);}
.dot.avoidon{background:var(--danger);box-shadow:0 0 8px var(--danger);}
.sensor-row .prog{margin-left:auto;font-size:10.5px;color:var(--muted);font-variant-numeric:tabular-nums;}
.hint{grid-column:1 / -1;font-size:11.5px;color:var(--muted);line-height:1.6;border-top:1px solid var(--line);padding-top:10px;}
.hint b{color:var(--text);}

/* ---- goal line ---- */
.goal{font-size:13px;color:var(--accent2);line-height:1.45;margin-bottom:8px;min-height:19px;}

/* ---- board / workspace ---- */
.board{position:relative;width:100%;margin:0 auto;}
canvas{background:#2c2544;border-radius:12px;display:block;
  cursor:crosshair;border:1px solid var(--line);width:100%;height:auto;touch-action:none;
  -webkit-user-select:none;user-select:none;}

/* timer + stars overlay (top-right, non-interactive) */
.hud{position:absolute;top:10px;right:10px;display:flex;align-items:center;gap:10px;pointer-events:none;
  background:rgba(12,17,30,.62);border:1px solid var(--line);border-radius:20px;padding:5px 12px;
  backdrop-filter:blur(3px);font-size:13px;}
.hud .timer{font-variant-numeric:tabular-nums;font-weight:700;}
.hud .timer.low{color:var(--danger);}
.hud .stars{color:var(--accent2);letter-spacing:1px;}

/* floating run + speed cluster (bottom-left of the workspace) */
.fab{position:absolute;left:10px;bottom:10px;display:flex;flex-direction:column;gap:6px;align-items:stretch;
  background:rgba(12,17,30,.62);border:1px solid var(--line);border-radius:12px;padding:7px;backdrop-filter:blur(3px);}
.fab .run{font-size:15px;padding:10px 16px;}
.speed{display:flex;gap:4px;}
.speed .sp{flex:1;text-align:center;padding:4px 7px;font-size:11px;border-radius:6px;cursor:pointer;
  background:var(--panel2);border:1px solid var(--line);color:var(--muted);}
.speed .sp.active{background:var(--accent);color:#0b1220;font-weight:700;border-color:var(--accent);}

/* banner overlay */
.banner{position:absolute;left:50%;top:16px;transform:translateX(-50%);max-width:80%;text-align:center;
  padding:9px 16px;border-radius:10px;font-size:13px;font-weight:600;display:none;backdrop-filter:blur(3px);}
.banner.win{display:block;background:rgba(18,58,36,.92);color:var(--ok);border:1px solid var(--ok);}
.banner.fail{display:block;background:rgba(58,20,32,.92);color:var(--danger);border:1px solid var(--danger);}

/* ---- build toolbar (below workspace) ---- */
.toolbar{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin-top:10px;
  background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:9px;}
.btn{background:var(--panel2);border:1px solid var(--line);color:var(--text);padding:9px 13px;border-radius:8px;
  cursor:pointer;font-size:13px;display:inline-flex;align-items:center;gap:7px;transition:.15s;}
.btn:hover:not(:disabled){border-color:var(--accent);}
.btn.active{background:var(--accent);color:#0b1220;font-weight:600;}
.btn:disabled{opacity:.34;cursor:not-allowed;}
.btn.run{background:var(--ok);color:#06210f;font-weight:700;border-color:transparent;}
.btn.run.paused{background:var(--accent2);color:#2a1600;}
.btn.reset{background:#2a1620;border-color:#5a2a3a;}
.count{background:#0c1120;padding:2px 8px;border-radius:20px;font-size:11px;color:var(--accent);}
/* the wheel tool can be dragged onto the board */
#btnWheel{cursor:grab;touch-action:none;}
#btnWheel:active,#btnWheel.dragging{cursor:grabbing;border-color:var(--accent);}
#btnWheel.dragging{background:var(--accent);color:#0b1220;}
.toolbar .spacer{flex:1;}
.par{font-size:11px;color:var(--muted);white-space:nowrap;}

/* ---- level-complete popup ---- */
.modal-backdrop{position:fixed;inset:0;background:rgba(4,7,14,.66);backdrop-filter:blur(3px);
  display:none;align-items:center;justify-content:center;z-index:60;padding:20px;}
.modal-backdrop.open{display:flex;animation:fadeIn .18s ease;}
@keyframes fadeIn{from{opacity:0}to{opacity:1}}
.modal{position:relative;background:var(--panel);border:1px solid var(--line);border-radius:16px;
  padding:26px 28px 22px;width:100%;max-width:360px;text-align:center;
  box-shadow:0 20px 60px rgba(0,0,0,.55);animation:pop .2s cubic-bezier(.2,.9,.3,1.2);}
@keyframes pop{from{transform:scale(.9);opacity:0}to{transform:scale(1);opacity:1}}
.modal-close{position:absolute;top:10px;right:12px;background:none;border:0;color:var(--muted);
  font-size:15px;cursor:pointer;padding:4px 6px;line-height:1;}
.modal-close:hover{color:var(--text);}
.modal-title{font-size:19px;font-weight:700;color:var(--ok);margin-bottom:8px;}
.modal-stars{font-size:30px;letter-spacing:5px;color:var(--accent2);margin-bottom:10px;}
.modal-stats{font-size:13px;color:var(--text);}
.modal-par{font-size:11.5px;color:var(--muted);margin-top:5px;line-height:1.5;}
.modal-actions{display:flex;gap:10px;margin-top:20px;}
.modal-actions .btn{flex:1;justify-content:center;}
.btn.primary{background:var(--ok);color:#06210f;font-weight:700;border-color:transparent;}
.btn.primary:hover:not(:disabled){filter:brightness(1.08);}