Кастомный курсор в Tilda
готовый код.

<div class="tselno-cursor" aria-hidden="true"></div>

<style>
.tselno-cursor { display: none; }
@media (pointer: fine) and (prefers-reduced-motion: no-preference) {
  .tselno-cursor {
    position: fixed;
    z-index: 99999;
    top: 0;
    left: 0;
    width: 14px;
    height: 14px;
    display: block;
    border-radius: 50%;
    background: #ff5c35;
    pointer-events: none;
    opacity: 0;
    transform: translate(-50%, -50%);
    transition: width .2s ease, height .2s ease, opacity .2s ease;
  }
  .tselno-cursor.is-visible { opacity: .9; }
  .tselno-cursor.is-active { width: 42px; height: 42px; opacity: .45; }
}
</style>

<script>
(function () {
  if (!window.matchMedia('(pointer: fine) and (prefers-reduced-motion: no-preference)').matches) return;
  var cursor = document.querySelector('.tselno-cursor');
  if (!cursor) return;

  document.addEventListener('mousemove', function (event) {
    cursor.style.left = event.clientX + 'px';
    cursor.style.top = event.clientY + 'px';
    cursor.classList.add('is-visible');
  });
  document.addEventListener('mouseleave', function () {
    cursor.classList.remove('is-visible');
  });
  document.addEventListener('mouseover', function (event) {
    if (event.target.closest('a, button, [role="button"]')) cursor.classList.add('is-active');
  });
  document.addEventListener('mouseout', function (event) {
    if (event.target.closest('a, button, [role="button"]')) cursor.classList.remove('is-active');
  });
})();
</script>