.overlay {
  display: none;
  background: rgba(255,255,255,0.85);
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
}
.overlay:target {
  display: block;
}
.overlay__dialog {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  transform: translate(0, -500%);
  transition: transform 3s ease-out;
  background: white;
  border: 1px solid #efefef;
  padding: 1em;
  overflow: scroll;
  padding: 30px 20px;
}
.overlay:target .overlay__dialog {
  display: block;
  transform: translate(0, 0);
}

.overlay__close {
  position: fixed;
  top: 10px;
  right: 20px;
  color: #aaaaaa;
  width: 40px;
  text-align: right;
  font-family: sans-serif;
  font-size: 30px;
  font-weight: 100;
  background: none;
}

.overlay {
  display: none;
  background: rgba(255,255,255,0.85);
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
}
.overlay:target {
  display: block;
}
.overlay__dialog {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  transform: translate(0, -500%);
  transition: transform 3s ease-out;
  background: white;
  border: 1px solid #efefef;
  padding: 1em;
  overflow: scroll;
  -webkit-overflow-scrolling: touch;
  padding: 30px 20px;
}
.overlay:target .overlay__dialog {
  display: block;
  transform: translate(0, 0);
}

.overlay__close {
  position: fixed;
  top: 10px;
  right: 20px;
  color: #aaaaaa;
  width: 40px;
  text-align: right;
  font-family: sans-serif;
  font-size: 30px;
  font-weight: 100;
  background: none;
}

Add momentum scrolling to ios
Add momentum scrolling to ios
