w3schools animation scale code example

Example 1: css animation scale image

css

.btn {
  transition: transform 250ms, opacity 400ms;
}

.btn:hover {
  transform: scale(1.2);
  opacity: 0;
}

Example 2: scale up and scale down animation in css

@-webkit-keyframes scaling {
From {
    -webkit-transform: scale(1.0);
}
To {
    -webkit-transform: scale(2.0);
}

#treeLeaves {
-webkit-animation: scaling 5s infinite alternate;
}