:root {
  --scroll-to-top-size: 4rem;
  --scroll-to-top-thickness: 0.75;
  /* Ring thickness (%): from 0 to 1 */
  --scroll-to-top-scroll-progress: 0%;
  --scroll-to-top-color: var(--wp--preset--color--tertiary);
  --scroll-to-top-color-lighter: #c3d1e5;
  --scroll-to-top-color-background: #fff;
}

.progress {
  position: fixed;
  right: 0;
  bottom: 0;
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  width: var(--scroll-to-top-size);
  height: var(--scroll-to-top-size);
  border-radius: 50%;
  background: conic-gradient(var(--scroll-to-top-color) 0%,
      var(--scroll-to-top-color) var(--scroll-to-top-scroll-progress),
      var(--scroll-to-top-color-lighter) var(--scroll-to-top-scroll-progress),
      var(--scroll-to-top-color-lighter) 100%);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.progress.visible {
  opacity: 1;
  pointer-events: auto;
}

.progress-inner {
  width: calc(var(--scroll-to-top-size) * var(--scroll-to-top-thickness));
  height: calc(var(--scroll-to-top-size) * var(--scroll-to-top-thickness));
  background-color: var(--scroll-to-top-color-background);
  border-radius: 50%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}