write css in javascript code example

Example 1: add style javascript

// Bad:
element.setAttribute("style", "background-color: red;");
// Good:
element.style.backgroundColor = "red";

Example 2: how to change style of an element using javascript

<html>
<body>

<p id="p2">Hello World!</p>

<script>
document.getElementById("p2").style.color = "blue";
</script>

<p>The paragraph above was changed by a script.</p>

</body>
</html>

Example 3: how to give css style in javascript

document.getElementById("myH1").style.color = "red";

Example 4: add css in javascript

document.getElementById("demo").style.display = "none";

Example 5: change color of css in js

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Change the Background Color with JavaScript</title>
<script>
    // Function to change webpage background color
    function changeBodyBg(color){
        document.body.style.background = color;
    }
    
    // Function to change heading background color
    function changeHeadingBg(color){
        document.getElementById("heading").style.background = color;
    }
</script>
</head>
<body>
    <h1 id="heading">This is a heading</h1>
    <p>This is a paragraph of text.</p>
    <hr>
    <div>
        <label>Change Webpage Background To:</label>
        <button type="button" onclick="changeBodyBg('yellow');">Yellow</button>
        <button type="button" onclick="changeBodyBg('lime');">Lime</button>
        <button type="button" onclick="changeBodyBg('orange');">Orange</button>
    </div>
    <br>
    <div>
        <label>Change Heading Background To:</label>
        <button type="button" onclick="changeHeadingBg('red');">Red</button>
        <button type="button" onclick="changeHeadingBg('green');">Green</button>
        <button type="button" onclick="changeHeadingBg('blue');">Blue</button>
    </div>
</body>
</html>

Example 6: add css style sheet with javascript

<head>

<script>
function myFunction() {
  var x = document.createElement("LINK");
  x.setAttribute("rel", "stylesheet");
  x.setAttribute("type", "text/css");
  x.setAttribute("href", "styles.css");
  document.head.appendChild(x);
}
myFunction()
</script>

</head>