#c {
  position: fixed;
  inset: 0;
  display: block;
}

#overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  display: flex;
  justify-content: center;
  padding-top: 10px;
  background: linear-gradient(180deg, rgba(0, 0, 0, 0.35), transparent 35%);
}