Toggle Group

<!-- Toggle Group — pill slides via translateX based on active index -->
<div class="nuda-toggleg" role="tablist">
  <button class="nuda-toggleg__opt"           type="button">Day</button>
  <button class="nuda-toggleg__opt is-active" type="button">Week</button>
  <button class="nuda-toggleg__opt"           type="button">Month</button>
  <span class="nuda-toggleg__pill"></span>
</div>

/* Toggle Group
   Segmented control: pill slides under the active option.
   Customize: --toggle-accent, --toggle-text-active */

.nuda-toggleg {
  --toggle-accent: #e4ff54;
  --toggle-text-active: #09090b;
  position: relative;
  display: inline-flex;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 10px;
  padding: 4px;
}

.nuda-toggleg__opt {
  position: relative;
  z-index: 2;
  padding: 7px 16px;
  background: transparent;
  border: none;
  color: #a1a1aa;
  font: 600 0.75rem ui-sans-serif, system-ui, sans-serif;
  cursor: pointer;
  border-radius: 6px;
  transition: color 0.3s;
}

.nuda-toggleg__opt.is-active {
  color: var(--toggle-text-active);
}

.nuda-toggleg__pill {
  position: absolute;
  z-index: 1;
  top: 4px;
  left: 4px;
  width: calc(33.33% - 2.6px);
  height: calc(100% - 8px);
  background: var(--toggle-accent);
  border-radius: 6px;
  box-shadow: 0 0 8px rgba(228, 255, 84, 0.3);
  transform: translateX(100%); /* second option active by default */
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Move from JS by setting transform: translateX(0 / 100% / 200%) */

/* Toggle Group — slides the pill to the clicked option. */

(function () {
  var group = document.querySelector('.nuda-toggleg');
  if (!group) return;

  var opts = group.querySelectorAll('.nuda-toggleg__opt');
  var pill = group.querySelector('.nuda-toggleg__pill');

  opts.forEach(function (btn, i) {
    btn.addEventListener('click', function () {
      opts.forEach(function (o) { o.classList.remove('is-active'); });
      btn.classList.add('is-active');
      pill.style.transform = 'translateX(' + (i * 100) + '%)';
    });
  });
})();