html, body { height: 100%; margin:0; background: linear-gradient(#bfe8ff, #e8f3ff); }
#nvc { width: 100%; height: 100%; display:block; }
.hud { position:fixed; top:10px; left:12px; background:rgba(255,255,255,0.75); color:#00324d;
       font: 14px/1.2 system-ui, -apple-system, Segoe UI, Roboto, sans-serif; padding:8px 10px; border-radius:8px; }
.label { position:fixed; padding:4px 8px; background:rgba(0,0,0,0.55); color:#fff; font:12px/1.2 system-ui; border-radius:6px; pointer-events:none; }