Transitions provide a way to control animation speed while changing CSS properties. It allows you to change CSS properties smoothly, over a given duration. A CSS transitions can be control by using below transitions property-
div {
width: 100px;
height: 100px;
background: red;
transition-property: width;
transition-duration: 2s;
transition-timing-function: linear;
transition-delay: 1s;
}
div:hover {
width: 500px;
}