.hui {
    /* the app's real tokens — ci/dashboard/src/index.css */
    --background: oklch(0.158 0.012 255);
    --foreground: oklch(0.92 0.01 240);
    --card: oklch(0.195 0.014 255);
    --primary: oklch(0.8 0.125 185);
    --muted: oklch(0.235 0.015 255);
    --muted-foreground: oklch(0.63 0.018 245);
    --border: oklch(1 0 0 / 9%);
    --canvas: oklch(0.17 0.013 255);
    --radius: 0.5rem;

    /* The app ships Chakra Petch / IBM Plex Sans / JetBrains Mono. They are not embedded
       here; if the site already loads them these stacks pick them up automatically. */
    --font-sans: 'IBM Plex Sans Variable', 'IBM Plex Sans', ui-sans-serif, system-ui, sans-serif;
    --font-mono: 'JetBrains Mono Variable', 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;

    all: initial;
    display: block; position: relative; overflow: hidden;
    font-family: var(--font-sans); font-size: 14px; line-height: 1.5;
    color: var(--foreground); background: var(--card);
    border: 1px solid var(--border); border-radius: var(--radius);
    -webkit-font-smoothing: antialiased;
  }
  .hui *, .hui *::before, .hui *::after { box-sizing: border-box; }

  /* breadcrumb — matches the app's drill-down header */
  .hui-crumb {
    display: flex; align-items: center; gap: 7px;
    padding: 7px 12px; border-bottom: 1px solid var(--border);
    font-family: var(--font-mono); font-size: 11px; color: var(--muted-foreground);
    position: relative; z-index: 2; background: var(--card);
  }
  .hui-crumb button {
    font: inherit; color: inherit; background: none; border: 0; cursor: pointer;
    display: inline-flex; align-items: center; gap: 5px; padding: 0;
  }
  .hui-crumb button:hover { color: var(--foreground); }
  .hui-crumb b { color: var(--foreground); font-weight: 500; }
  .hui-crumb .sep { opacity: .6; }

  /* canvas: dotted background, like ReactFlow's Dots variant (gap 16, size 1) */
  .hui-canvas {
    position: relative; height: 440px; overflow: hidden; background: var(--canvas);
    background-image: radial-gradient(oklch(1 0 0 / 13%) 1px, transparent 1px);
    background-size: 16px 16px;
    cursor: grab; touch-action: none;
  }
  .hui-canvas[data-panning] { cursor: grabbing; }
  .hui-vp { position: absolute; left: 0; top: 0; transform-origin: 0 0; will-change: transform; }
  .hui-edges { position: absolute; left: 0; top: 0; overflow: visible; pointer-events: none; }
  .hui-edges path { fill: none; stroke: oklch(0.63 0.018 245 / 60%); stroke-width: 1.4; }

  /* blocks — 160px wide, same type scale as the app's PeriphNode */
  .hui-node {
    position: absolute; width: 160px; padding: 6px 10px;
    border: 1px solid var(--border); border-radius: 6px; background: var(--card);
    box-shadow: 0 1px 2px oklch(0 0 0 / 25%);
    cursor: pointer; user-select: none; touch-action: none;
    transition: border-color .15s, box-shadow .15s;
  }
  .hui-node:hover { border-color: oklch(0.8 0.125 185 / 50%); }
  .hui-node[data-sel] { border-color: var(--primary); box-shadow: 0 0 0 1px var(--primary); }
  .hui-node[data-dragging] { cursor: grabbing; box-shadow: 0 6px 18px oklch(0 0 0 / 45%); }
  .hui-node .n { font-family: var(--font-mono); font-size: 11px; font-weight: 500; line-height: 1.45;
                 white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
  .hui-node .t { font-family: var(--font-mono); font-size: 11px; color: var(--primary); line-height: 1.45;
                 white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
  .hui-node .r { font-family: var(--font-mono); font-size: 10px; color: var(--muted-foreground); line-height: 1.45;
                 white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

  /* machine block (top level) */
  .hui-node[data-machine] { width: 210px; padding: 0; }
  .hui-node[data-machine] .mh {
    display: flex; align-items: center; gap: 7px; padding: 8px 10px;
  }
  .hui-node[data-machine] .mh .nm { font-family: var(--font-mono); font-size: 12px; font-weight: 500; }
  .hui-node[data-machine] .tag {
    margin-left: auto; font-family: var(--font-mono); font-size: 9px; letter-spacing: .06em;
    padding: 1px 6px; border-radius: 4px; background: oklch(0.8 0.125 185 / 15%); color: var(--primary);
  }
  .hui-node[data-machine] .mf {
    display: flex; align-items: center; gap: 6px; padding: 6px 10px;
    border-top: 1px solid var(--border); font-family: var(--font-mono);
    font-size: 10px; color: var(--muted-foreground);
  }
  .hui-node[data-machine] .mf .open { margin-left: auto; color: var(--primary); }

  /* edge count label */
  .hui-lbl {
    position: absolute; transform: translate(-50%, -50%);
    font-family: var(--font-mono); font-size: 9px; line-height: 1;
    padding: 1px 3px; border-radius: 3px;
    background: oklch(0.195 0.014 255 / 85%); color: var(--muted-foreground);
    pointer-events: none;
  }

  .hui-note {
    position: absolute; left: 10px; bottom: 8px; z-index: 2;
    font-family: var(--font-mono); font-size: 10px; color: var(--muted-foreground);
    pointer-events: none; opacity: .75;
  }