The HTML DOM allows JavaScript to change the style of HTML elements.
Changing HTML Style
To change the style of an HTML element, use this syntax:
document.getElementById(id).style.property = new style
The following example changes the style of a <p> element :
Example
<html>
<body>
<p id="p2">Hello World!</p>
<script>
document.getElementById("p2").style.color = "blue";
</script>
</body>
</html>