:root{
  --bg:#0f141b;
  --panel:#151c25;
  --panel2:#1b2430;
  --line:#2a3543;
  --text:#e8edf4;
  --muted:#8e9baa;
  --accent:#2f8cff;
  --accent2:#66aaff;
  --danger:#ff6b6b;
}
*{box-sizing:border-box}
html,body{margin:0;height:100%;font-family:Inter,Segoe UI,Arial,sans-serif;background:var(--bg);color:var(--text);overflow:hidden}
button,input{font:inherit}
.topbar{height:64px;background:#111821;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 18px}
.brand{display:flex;gap:12px;align-items:center}
.logo{width:36px;height:36px;border-radius:9px;background:linear-gradient(145deg,#2f8cff,#1456b8);display:grid;place-items:center;font-weight:800;font-size:20px}
.brand-title{font-weight:700;letter-spacing:.2px}
.brand-subtitle{font-size:11px;color:var(--muted);margin-top:2px}
.top-actions{display:flex;gap:12px;align-items:center}
.badge{font-size:11px;padding:4px 8px;border:1px solid #31547f;border-radius:99px;color:#8fc0ff;background:#15263b}
.workspace{display:grid;grid-template-columns:86px 1fr 260px;height:calc(100vh - 64px)}
.toolbar{background:#111821;border-right:1px solid var(--line);padding:12px 8px;overflow-y:auto}
.tool-section{margin-bottom:20px}
.section-title{font-size:10px;color:#718092;letter-spacing:1.1px;margin:0 5px 8px}
.tool{width:100%;border:1px solid transparent;background:transparent;color:#b7c2cf;border-radius:8px;padding:8px 5px;margin:2px 0;cursor:pointer;display:flex;flex-direction:column;align-items:center;gap:4px;font-size:10px}
.tool:hover{background:#1b2633;color:white}
.tool.active{background:#17375b;border-color:#275f9c;color:#cfe6ff}
.tool.emphasis{border-color:#26496f}
.tool-icon{font-size:21px;line-height:22px}
.main-area{min-width:0;position:relative}
.panel{display:none;height:100%;background:#11171e}
.active-panel{display:block}
.panel-head{height:44px;border-bottom:1px solid var(--line);background:#151c25;display:flex;align-items:center;justify-content:space-between;padding:0 14px;font-size:13px}
.muted{color:var(--muted);font-size:12px;margin-left:8px}
.coords{font-family:Consolas,monospace;color:#8f9cab;font-size:12px}
.canvas-wrap{height:calc(100% - 44px);position:relative}
#sketchCanvas{width:100%;height:100%;display:block;background:#101820;cursor:crosshair}
.grid-small{fill:none;stroke:#1a2732;stroke-width:.6}
.grid-major{fill:none;stroke:#263542;stroke-width:1}
.axis-x{stroke:#b54a4a;stroke-width:1.4}
.axis-y{stroke:#4a9d64;stroke-width:1.4}
.sketch-shape{fill:none;stroke:#79b8ff;stroke-width:2;vector-effect:non-scaling-stroke;cursor:pointer}
.sketch-shape:hover,.sketch-shape.selected{stroke:#ffd166;stroke-width:3}
.preview{fill:none;stroke:#8b99a8;stroke-width:1.5;stroke-dasharray:5 4;vector-effect:non-scaling-stroke}
.point{fill:#ffd166}
.hint{position:absolute;left:12px;bottom:12px;background:#111b25cc;border:1px solid #2b3947;border-radius:8px;padding:8px 11px;font-size:12px;color:#a8b4c0;pointer-events:none}
.properties{background:#151c25;border-left:1px solid var(--line);padding:12px}
.properties-head{font-size:11px;letter-spacing:1px;color:#798798;padding:3px 3px 10px;border-bottom:1px solid var(--line)}
.property-card{padding:12px 4px;min-height:80px;border-bottom:1px solid var(--line);font-size:12px}
.property-row{display:grid;grid-template-columns:1fr 95px;gap:8px;align-items:center;margin:8px 0}
.property-row input{width:100%;background:#10161e;border:1px solid #344252;color:white;border-radius:5px;padding:5px 7px}
.tree{padding-top:16px}
.tree-item{font-size:12px;padding:7px 6px;border-radius:5px;color:#aeb9c5}
.tree-item.child{padding-left:22px}
.active-tree{background:#1a2c40;color:#cfe6ff}
.hidden{display:none!important}
.ghost-btn,.primary-btn{border:1px solid #344252;border-radius:7px;padding:7px 11px;cursor:pointer}
.ghost-btn{background:#17202a;color:#bac6d2}
.ghost-btn:hover{background:#202c38}
.primary-btn{background:#2378dd;border-color:#368be9;color:white}
.small{padding:5px 8px;font-size:11px}
#viewer3d{height:calc(100% - 44px);width:100%}
.empty-state{position:absolute;left:50%;top:50%;transform:translate(-50%,-40%);display:flex;flex-direction:column;align-items:center;gap:8px;color:#768595;pointer-events:none}
.empty-state strong{color:#b2bdc9}
.empty-cube{font-size:72px;color:#334557}
.modal{position:fixed;inset:0;background:#0009;display:grid;place-items:center;z-index:100}
.modal-card{width:360px;background:#18212b;border:1px solid #344353;border-radius:12px;padding:18px;box-shadow:0 20px 80px #0008}
.modal-title{font-size:18px;font-weight:700;margin-bottom:18px}
.modal-card label{font-size:12px;color:#aeb8c3}
.input-unit{display:flex;align-items:center;margin-top:7px;border:1px solid #374655;background:#111820;border-radius:7px;overflow:hidden}
.input-unit input{flex:1;background:transparent;color:white;border:0;padding:9px;outline:none}
.input-unit span{padding:0 10px;color:#8b99a8}
.modal-note{font-size:11px;color:#8c99a6;margin-top:12px;line-height:1.5}
.modal-actions{display:flex;justify-content:flex-end;gap:8px;margin-top:18px}
.toast{position:fixed;right:18px;bottom:18px;padding:10px 14px;border-radius:8px;background:#20354a;border:1px solid #356a9f;color:#dcecff;font-size:12px;z-index:120}
@media(max-width:900px){
  .workspace{grid-template-columns:72px 1fr}
  .properties{display:none}
}