JavaScript HTML DOM - Changing CSS
The HTML DOM allows JavaScript to modify the style of HTML elements.
Changing HTML Style
To change the style of an HTML element, use the following syntax:
document.getElementById(id).style.property = "new style";
Example: Changing Text Color
The following example changes the color of a <p> element:
<!DOCTYPE html><html><body>
<p id="p2">Hello World!</p><script>document.getElementById("p2").style.color = "blue";
</script>
</body>
</html>
Using Events
The HTML DOM allows you to execute code when an event occurs. Events are triggered by the browser when actions happen to HTML elements, such as:
- An element being clicked
- The page loading
- Input fields being changed
You will learn more about events in the next chapter of this tutorial.
Example: Changing Style on Click
This example changes the style of the HTML element with id="id1" when the user clicks a button:
<!DOCTYPE html>
<html><body><h1 id="id1">My Heading 1</h1>
<button type="button" onclick="document.getElementById('id1').style.color = 'red'">Click Me!</button>
</body>
</html>
More Examples
Visibility
You can control the visibility of an element to make it visible or invisible.
HTML DOM Style Object Reference
For a comprehensive list of all HTML DOM style properties, refer to our complete HTML DOM Style Object Reference.
Test Yourself With Exercises
Exercise:
Change the text color of the <p> element to "red".
<p id="demo">
Some text</p>
<script>document.getElementById("demo").style.color = "red";
</script>
