files/en-us/web/api/csstransition/index.md
{{APIRef("Web Animations")}}
The CSSTransition interface of the {{domxref('Web Animations API','','',' ')}} represents an {{domxref("Animation")}} object used for a CSS Transition.
{{InheritanceDiagram}}
This interface inherits properties from its parent, {{domxref("Animation")}}.
This interface inherits methods from its parent, {{domxref("Animation")}}.
No specific methods.
The transition in the following example changes the width of the box on hover. Calling {{domxref("Element.getAnimations()")}} returns an array of all {{domxref("Animation")}} objects. In our case this returns a CSSTransition object, representing the animation created.
.box {
background-color: #165baa;
color: white;
width: 100px;
height: 100px;
transition: width 4s;
}
.box:hover {
width: 200px;
}
const item = document.querySelector(".box");
item.addEventListener("transitionrun", () => {
let animations = document.querySelector(".box").getAnimations();
console.log(animations[0]);
});
{{Specifications}}
{{Compat}}