.overlay-index {
  position: absolute; 
  bottom: 0; 
  background: rgb(0, 0, 0);
  background: rgba(0, 0, 0, 0.8); /* Black see-through */
  color: #f1f1f1; 
  width: 100%;
  height: 100%;
  transition: .5s ease;
  color: white;
  padding: 20px;
}