.mybtn:active {
  transform: scale(0.9);
}
.mybtn:hover {
  background-color: lightgray;
  color: rgb(255, 255, 255);
}
.overlay {
  position: fixed;
  width: 100%;
  height: 100%;
  z-index: 1000;
  left: 0px;
  top: 0px;
  background-color: grey;
  opacity: 0.3;
  filter: alpha(opacity=30);
}