Pure CSS Modal

<!-- Pure CSS Modal — :target dialog, zero JS -->
<div class="nuda-css-modal">
  <a class="nuda-css-modal__open" href="#nuda-css-modal-demo">Open modal</a>

  <div class="nuda-css-modal__overlay" id="nuda-css-modal-demo">
    <div class="nuda-css-modal__dialog" role="dialog" aria-modal="true"
         aria-labelledby="nuda-css-modal-title">
      <h3 class="nuda-css-modal__title" id="nuda-css-modal-title">Confirm action</h3>
      <p class="nuda-css-modal__text">This dialog opens via the URL hash. Pure CSS :target.</p>
      <a class="nuda-css-modal__close" href="#">Close</a>
    </div>
  </div>
</div>

/* Pure CSS Modal
   The :target pseudo-class shows the overlay when its id
   is the URL hash. No JS.
   Customize: --nuda-css-modal-accent */

.nuda-css-modal {
  --nuda-css-modal-accent: #e4ff54;
}

.nuda-css-modal__open {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0.6rem 1.2rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: #09090b;
  background: var(--nuda-css-modal-accent);
  border-radius: 8px;
  text-decoration: none;
  cursor: pointer;
}

.nuda-css-modal__overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.6);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
  z-index: 100;
}

.nuda-css-modal__dialog {
  width: 90%;
  max-width: 400px;
  padding: 1.5rem;
  background: #111114;
  border: 1px solid rgba(228, 255, 84, 0.2);
  border-radius: 14px;
  color: #fff;
  transform: scale(0.9);
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 0 18px 50px rgba(0, 0, 0, 0.6);
}

.nuda-css-modal__title { margin: 0 0 0.5rem; font-size: 1.05rem; font-weight: 700; }
.nuda-css-modal__text  { margin: 0 0 1rem; font-size: 0.85rem; color: #999; }

.nuda-css-modal__close {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.5rem 1rem;
  font-size: 0.85rem;
  color: #ccc;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 8px;
  text-decoration: none;
  cursor: pointer;
}

/* Open state — driven entirely by the URL hash */
.nuda-css-modal__overlay:target {
  opacity: 1;
  pointer-events: auto;
}

.nuda-css-modal__overlay:target .nuda-css-modal__dialog {
  transform: scale(1);
}

@media (prefers-reduced-motion: reduce) {
  .nuda-css-modal__overlay,
  .nuda-css-modal__dialog { transition: none; }
}