async function peekGauge(SVG) {
    // Delay just a tad to let the user aclimatize beforehand.
    await new Promise(resolve => setTimeout(resolve, 1000));

    // Early exit if it's already engaged
    if (SVG.classList.contains('state--expanded')) return;

    // To visually get the outer ring to peek on the edge, we need the inner ring on top. This is SVG's equivalent to `innerElem.zIndex = 100`
    const inner = dom.find('.lh-exp-gauge__inner', SVG);
    const id = `uniq-${Math.random()}`;
    inner.setAttribute('id', id);
    const useElem = dom.createSVGElement('use');
    useElem.setAttribute('href', `#${id}`);
    // for paint order this must come _after_ the outer.
    SVG.appendChild(useElem);

    const peekDurationSec = 2.5;
    SVG.style.setProperty('--peek-dur', `${peekDurationSec}s`);
    SVG.classList.add('state--peek', 'state--expanded');

    // Fancy double cleanup
    const cleanup = () => {
      SVG.classList.remove('state--peek', 'state--expanded');
      useElem.remove();
    };
    const tId = setTimeout(() => {
      SVG.removeEventListener('mouseenter', handleEarlyInteraction);
      cleanup();
    }, peekDurationSec * 1000 * 1.5); // lil extra time just cuz
    function handleEarlyInteraction() {
      clearTimeout(tId);
      cleanup();
    }
    SVG.addEventListener('mouseenter', handleEarlyInteraction, {once: true});
  }
On the first run, tease with a little peek reveal
@param {SVGElement} SVG