Menu Morph

<!--
  Menu Morph - transitions.dev-inspired primitive for HyperFrames.

  Paste the markup, CSS and script into a composition. Use the timeline
  integration note at the bottom as the starting point for deterministic GSAP
  animation.

  Variables. The script reads each one, falls back to the declared default on
  anything missing or invalid, and writes the result as a custom property the
  CSS consumes (or, for the actions, as the pills themselves). The timeline
  recipe below is untouched by them: it still pops the button, crosses the two
  outer bars and staggers whatever pills are present.

    - actions (text, default Text, Image, Audio): comma separated labels for
      the pills that fan out under the button, up to six. The stagger picks up
      the new count.
    - tone (ink | green | blue | violet, default ink): colour of the round
      button behind the white bars. ink is a literal near-black; the other three
      ride the composition's own brand, accent and accent-2 tokens and fall back
      to that same ink when the composition declares none.
    - size (52 to 112 px, default 68): diameter of the round button. The bar
      width is a fixed fraction of it, so the whole glyph scales together.

  On every default the result is identical to the original: a 68px near-black
  button with 24px bars over three pills.
-->

<div
  class="hf-transition-menu-morph"
  data-composition-variables='[
    { "id": "actions", "type": "string", "role": "content", "label": "Actions", "description": "Comma separated labels for the pills that fan out under the button. Up to six.", "default": "Text, Image, Audio" },
    { "id": "tone", "type": "enum", "role": "style", "label": "Tone", "description": "Colour of the round button behind the white bars.", "default": "ink", "options": [{ "value": "ink", "label": "Ink" }, { "value": "green", "label": "Green" }, { "value": "blue", "label": "Blue" }, { "value": "violet", "label": "Violet" }] },
    { "id": "size", "type": "number", "role": "layout", "label": "Button size", "description": "Diameter of the round button in pixels. The bars scale with it.", "default": 68, "min": 52, "max": 112, "step": 4, "unit": "px" }
  ]'
>
  <button class="hf-transition-menu-button" type="button" aria-label="Menu">
    <span></span><span></span><span></span>
  </button>
  <div class="hf-transition-menu-actions">
    <div>Text</div>
    <div>Image</div>
    <div>Audio</div>
  </div>
</div>

<style>
  .hf-transition-menu-morph {
    position: relative;
    display: grid;
    place-items: center;
    width: 360px;
    height: 220px;
    font-family: Inter, system-ui, sans-serif;
  }
  .hf-transition-menu-button {
    z-index: 2;
    display: grid;
    place-items: center;
    gap: 5px;
    width: var(--hf-menu-size, 68px);
    height: var(--hf-menu-size, 68px);
    border: 0;
    border-radius: 999px;
    background: var(--hf-menu-bg, #18181b);
    box-shadow: 0 22px 58px rgba(0, 0, 0, 0.22);
  }
  .hf-transition-menu-button span {
    width: calc(var(--hf-menu-size, 68px) * 6 / 17);
    height: 3px;
    border-radius: 999px;
    background: #ffffff;
    transform-origin: center;
  }
  .hf-transition-menu-actions {
    position: absolute;
    display: flex;
    gap: 10px;
    bottom: 20px;
  }
  .hf-transition-menu-actions div {
    padding: 9px 13px;
    border-radius: 999px;
    background: #ffffff;
    color: #18181b;
    font-size: 13px;
    font-weight: 850;
    box-shadow: 0 14px 34px rgba(0, 0, 0, 0.12);
  }
</style>

<script>
  (function () {
    "use strict";

    var vars =
      window.__hyperframes && window.__hyperframes.getVariables
        ? window.__hyperframes.getVariables()
        : {};

    // Anything missing or invalid returns to its declared default.
    // The button is the one accent-carrying element here, so the three
    // chromatic options ride the composition's own tokens and fall back to ink.
    var tones = {
      ink: "#18181b",
      green: "var(--brand, #18181b)",
      blue: "var(--accent, #18181b)",
      violet: "var(--accent-2, #18181b)",
    };

    function pick(table, value, fallback) {
      return Object.prototype.hasOwnProperty.call(table, value) ? value : fallback;
    }

    var labels = [];
    if (typeof vars.actions === "string") {
      var parts = vars.actions.split(",");
      for (var p = 0; p < parts.length && labels.length < 6; p += 1) {
        var label = parts[p].trim();
        if (label) {
          labels.push(label);
        }
      }
    }
    if (!labels.length) {
      labels = ["Text", "Image", "Audio"];
    }

    var size =
      typeof vars.size === "number" || typeof vars.size === "string" ? Number(vars.size) : NaN;
    size = isFinite(size) && size > 0 ? Math.min(112, Math.max(52, size)) : 68;

    var tone = tones[pick(tones, vars.tone, "ink")];

    var roots = document.querySelectorAll(".hf-transition-menu-morph");
    for (var i = 0; i < roots.length; i += 1) {
      roots[i].style.setProperty("--hf-menu-size", size + "px");
      roots[i].style.setProperty("--hf-menu-bg", tone);
      var row = roots[i].querySelector(".hf-transition-menu-actions");
      if (!row) {
        continue;
      }
      while (row.firstChild) {
        row.removeChild(row.firstChild);
      }
      for (var j = 0; j < labels.length; j += 1) {
        var pill = document.createElement("div");
        pill.textContent = labels[j];
        row.appendChild(pill);
      }
    }
  })();
</script>

<!--
  Timeline integration:
  tl.fromTo('.hf-transition-menu-button', { scale: 0.72, opacity: 0 }, { scale: 1, opacity: 1, duration: 0.34, ease: 'back.out(1.8)' }, 0.3);
  tl.to('.hf-transition-menu-button span:nth-child(1)', { y: 8, rotation: 45, duration: 0.24, ease: 'power2.inOut' }, 0.78);
  tl.to('.hf-transition-menu-button span:nth-child(2)', { opacity: 0, duration: 0.18, ease: 'power1.out' }, 0.78);
  tl.to('.hf-transition-menu-button span:nth-child(3)', { y: -8, rotation: -45, duration: 0.24, ease: 'power2.inOut' }, 0.78);
  tl.fromTo('.hf-transition-menu-actions div', { y: 28, opacity: 0, scale: 0.86 }, { y: 0, opacity: 1, scale: 1, duration: 0.26, stagger: 0.06, ease: 'back.out(1.6)' }, 0.96);
-->