Badge Pop

<!--
  Badge Pop - 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 unrecognised, and writes the result as a custom property
  the CSS below consumes, or as the badge text. The timeline recipe at the
  bottom is untouched by them: it keeps popping the same badge, whatever the
  badge says and however it is coloured.

    - count (any text up to four characters, default "3"): what the badge
      reads. Use it to say 1, 12, 99+ or NEW.
    - accent (red | blue | green | violet, default red): the badge colour
      family. red is the literal notification convention; the other three ride
      the composition's own accent, brand and accent-2 tokens and fall back to
      ink when the composition declares none. All four clear 3:1 against the
      white count.
    - surface (light | dark, default light): the chrome of the button and the
      ring around the badge. light suits bright frames, dark suits dark ones.

  On every default the result is identical to the original: a white bell tile
  with a red 3 badge.
-->

<div
  class="hf-transition-badge-pop"
  data-composition-variables='[
    { "id": "count", "type": "string", "role": "style", "label": "Count", "description": "Text shown inside the notification badge, up to four characters.", "default": "3", "maxLength": 4 },
    { "id": "accent", "type": "enum", "role": "style", "label": "Accent", "description": "Colour family of the badge.", "default": "red", "options": [{ "value": "red", "label": "Red" }, { "value": "blue", "label": "Blue" }, { "value": "green", "label": "Green" }, { "value": "violet", "label": "Violet" }] },
    { "id": "surface", "type": "enum", "role": "style", "label": "Surface", "description": "Chrome of the button and the badge ring: light for bright frames, dark for dark ones.", "default": "light", "options": [{ "value": "light", "label": "Light" }, { "value": "dark", "label": "Dark" }] }
  ]'
>
  <button class="hf-transition-badge-button" type="button" aria-label="Notifications">
    <svg viewBox="0 0 24 24" aria-hidden="true">
      <path d="M18 8a6 6 0 10-12 0c0 7-3 7-3 7h18s-3 0-3-7" />
      <path d="M10 20a2 2 0 004 0" />
    </svg>
  </button>
  <span class="hf-transition-badge-count">3</span>
</div>

<style>
  .hf-transition-badge-pop {
    --hf-badge-pop-accent: #ef4444;
    --hf-badge-pop-surface: #ffffff;
    --hf-badge-pop-border: #e4e4e7;
    --hf-badge-pop-ink: #18181b;
    position: relative;
    display: inline-grid;
    place-items: center;
    font-family: Inter, system-ui, sans-serif;
  }
  .hf-transition-badge-button {
    display: grid;
    place-items: center;
    width: 76px;
    height: 76px;
    border: 1px solid var(--hf-badge-pop-border);
    border-radius: 22px;
    background: var(--hf-badge-pop-surface);
    color: var(--hf-badge-pop-ink);
    box-shadow: 0 20px 58px rgba(0, 0, 0, 0.12);
  }
  .hf-transition-badge-button svg {
    width: 30px;
    height: 30px;
    fill: none;
    stroke: currentColor;
    stroke-width: 2.2;
    stroke-linecap: round;
    stroke-linejoin: round;
  }
  .hf-transition-badge-count {
    position: absolute;
    right: -8px;
    top: -8px;
    display: grid;
    place-items: center;
    min-width: 30px;
    height: 30px;
    padding: 0 8px;
    border: 3px solid var(--hf-badge-pop-surface);
    border-radius: 999px;
    background: var(--hf-badge-pop-accent);
    color: #ffffff;
    font-size: 13px;
    font-weight: 900;
    transform-origin: center;
  }
</style>

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

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

    // Unrecognised overrides return to their declared defaults.
    function pick(table, value, fallback) {
      return Object.prototype.hasOwnProperty.call(table, value) ? value : fallback;
    }

    // The badge is the one accent-carrying element here. red is the literal
    // notification convention and stays; the decorative options ride the
    // composition's own tokens and fall back to ink.
    var accents = {
      red: "#ef4444",
      blue: "var(--accent, #18181b)",
      green: "var(--brand, #18181b)",
      violet: "var(--accent-2, #18181b)",
    };
    var surfaces = {
      light: { surface: "#ffffff", border: "#e4e4e7", ink: "#18181b" },
      dark: { surface: "#101014", border: "#2a2a32", ink: "#fafafa" },
    };

    var accent = accents[pick(accents, vars.accent, "red")];
    var surface = surfaces[pick(surfaces, vars.surface, "light")];
    var count =
      typeof vars.count === "string" && vars.count.trim() ? vars.count.trim().slice(0, 4) : "3";

    var roots = document.querySelectorAll(".hf-transition-badge-pop");
    for (var i = 0; i < roots.length; i += 1) {
      var root = roots[i];
      root.style.setProperty("--hf-badge-pop-accent", accent);
      root.style.setProperty("--hf-badge-pop-surface", surface.surface);
      root.style.setProperty("--hf-badge-pop-border", surface.border);
      root.style.setProperty("--hf-badge-pop-ink", surface.ink);
      var label = root.querySelector(".hf-transition-badge-count");
      if (label) {
        label.textContent = count;
      }
    }
  })();
</script>

<!--
  Timeline integration:
  tl.fromTo('.hf-transition-badge-button', { y: 18, opacity: 0 }, { y: 0, opacity: 1, duration: 0.34, ease: 'power2.out' }, 0.35);
  tl.fromTo('.hf-transition-badge-count', { scale: 0, opacity: 0 }, { scale: 1, opacity: 1, duration: 0.42, ease: 'back.out(2.4)' }, 0.7);
  tl.to('.hf-transition-badge-count', { scale: 1.18, duration: 0.12, yoyo: true, repeat: 1, ease: 'power1.inOut' }, 1.15);
-->