Menu to Close

<button class="nuda-icon-burger" type="button" aria-label="Toggle menu" aria-pressed="false">
  <svg class="nuda-icon-burger__svg" viewBox="0 0 24 24" aria-hidden="true">
    <line class="nuda-icon-burger__top" x1="3" y1="6"  x2="21" y2="6" />
    <line class="nuda-icon-burger__mid" x1="3" y1="12" x2="21" y2="12" />
    <line class="nuda-icon-burger__bot" x1="3" y1="18" x2="21" y2="18" />
  </svg>
</button>

/* Menu to Close
   Three bars rotate/collapse into an X. Active state lights up lime.
   GPU-only: transform + opacity. Customize: --icon-accent */

.nuda-icon-burger {
  --icon-accent: #e4ff54;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: #09090b;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 10px;
  color: #fafafa;
  cursor: pointer;
  transition: border-color 0.25s, color 0.25s;
}

.nuda-icon-burger:hover,
.nuda-icon-burger:focus-visible {
  border-color: rgba(228, 255, 84, 0.4);
  outline: none;
}

.nuda-icon-burger:focus-visible {
  box-shadow: 0 0 0 2px rgba(228, 255, 84, 0.5);
}

.nuda-icon-burger[aria-pressed="true"] { color: var(--icon-accent); }

.nuda-icon-burger__svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  fill: none;
}

.nuda-icon-burger__svg line {
  transition: transform 0.3s cubic-bezier(0.4, 0.2, 0.2, 1), opacity 0.2s;
  transform-origin: center;
  will-change: transform, opacity;
}

.nuda-icon-burger[aria-pressed="true"] .nuda-icon-burger__top {
  transform: translateY(6px) rotate(45deg);
}

.nuda-icon-burger[aria-pressed="true"] .nuda-icon-burger__mid {
  opacity: 0;
  transform: scaleX(0);
}

.nuda-icon-burger[aria-pressed="true"] .nuda-icon-burger__bot {
  transform: translateY(-6px) rotate(-45deg);
}

@media (prefers-reduced-motion: reduce) {
  .nuda-icon-burger__svg line { transition: none; }
}

/* Menu to Close — vanilla JS
   Flips aria-pressed; CSS handles the morph. */

(function () {
  document.querySelectorAll(".nuda-icon-burger").forEach(function (btn) {
    btn.addEventListener("click", function () {
      var pressed = btn.getAttribute("aria-pressed") === "true";
      btn.setAttribute("aria-pressed", String(!pressed));
    });
  });
})();