JavaScript animations can handle things that CSS can’t. For instance, moving along a complex path, with a timing function different from Bezier curves, or an animation on a canvas.An animation can be implemented as a sequence of frames – usually small changes to HTML/CSS properties.
The idea behind Javascript-based animation is fairly simple; a number of DOM elements (<img />, <div> or otherwise) are moved around the page according to some sort of pattern determined by a logical equation or function.
EXAMPLE
<!DOCTYPE html>
<html>
<style>
#myContainer {
width: 400px;
height: 400px;
position: relative;
background: black;
}
#myAnimation {
width: 50px;
height: 50px;
position: absolute;
background-color: #FF4B4B;
border-radius: 50px;
}
</style>
<body>
<p>
<button onclick="myMove()">Click Me</button>
</p>
<div id ="myContainer">
<div id ="myAnimation"></div>
</div>
<script>
function myMove() {
var elem = document.getElementById("myAnimation");
var pos = 0;
var id = setInterval(frame, 10);
function frame() {
if (pos == 350) {
clearInterval(id);
} else {
pos++;
elem.style.top = pos + 'px';
elem.style.left = pos + 'px';
document.getElementById("myAnimation").style["boxShadow"] = "10px 30px 30px 5px white";
}
}
}
</script>
</body>
</html>
