Answers for "css img width animation"

css animation scale image

css

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

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

css change width animation

-webkit-transition: width 1s ease-in-out;
    -moz-transition: width 1s ease-in-out;
    -o-transition: width 1s ease-in-out;
    transition: width 1s ease-in-out;