Neon Toggle

<!-- Neon Toggle — switch with a glowing track -->
<button class="nuda-neon-toggle is-on" role="switch" aria-checked="true" aria-label="Toggle neon">
  <span class="nuda-neon-toggle__thumb"></span>
</button>

/* ── Neon Toggle ─────────────────────────────────────────────
   Track + thumb light up when the .is-on class is present.
   Toggle .is-on (and aria-checked) from JS on click.
   Customize:
     --neon-toggle-color : neon hue
   ──────────────────────────────────────────────────────────── */
.nuda-neon-toggle {
  --neon-toggle-color: #e4ff54;
  position: relative;
  width: 56px;
  height: 30px;
  padding: 0;
  border: 1px solid rgba(228, 255, 84, 0.2);
  border-radius: 99px;
  background: #16161c;
  cursor: pointer;
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

.nuda-neon-toggle__thumb {
  position: absolute;
  top: 50%;
  left: 3px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #5b5b66;
  transform: translateY(-50%);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), background 0.3s, box-shadow 0.3s;
  will-change: transform;
}

.nuda-neon-toggle.is-on {
  border-color: rgba(228, 255, 84, 0.7);
  box-shadow: inset 0 0 10px rgba(228, 255, 84, 0.3), 0 0 12px rgba(228, 255, 84, 0.35);
}

.nuda-neon-toggle.is-on .nuda-neon-toggle__thumb {
  transform: translate(26px, -50%);
  background: var(--neon-toggle-color);
  box-shadow: 0 0 8px var(--neon-toggle-color), 0 0 16px rgba(228, 255, 84, 0.7);
}

.nuda-neon-toggle:focus-visible {
  outline: 2px solid var(--neon-toggle-color);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .nuda-neon-toggle,
  .nuda-neon-toggle__thumb { transition: none; }
}

/* Toggle the .is-on class and keep aria-checked in sync. */
document.querySelectorAll(".nuda-neon-toggle").forEach(function (sw) {
  sw.addEventListener("click", function () {
    var on = sw.classList.toggle("is-on");
    sw.setAttribute("aria-checked", on ? "true" : "false");
  });
});