CSS Reference

Quick Reference

The border-bottom-width property sets the width of an element’s bottom border. An element must have a border before you can change the width.

div {
    border-bottom-width: thin;
}

Default

Default valuenone
Inherited valuesno
Can it be animated?no

These are the allowed values.

ValueDescription
mediumSpecifies a medium border (default)
thinSpecifies a thin border
thickSpecifies a thick border
lengthAllows you to define the thickness of the border in pixels
initialSets this property to its default value
inheritInherits this property from its parent element

Using JavaScript

The HTML element can also be styled using JavaScript and the element’s id.

document.getElementById('my_div').style.borderBottomWidth = 'thin';
<button onclick='my_function()'>Click Here</button>

<script>
function my_function() {
    document.getElementById('my_div').style.borderBottomWidth = 'thin';
}
</script>

CSS Notes:


We’d like to acknowledge that we learned a great deal of our coding from W3Schools and TutorialsPoint, borrowing heavily from their teaching process and excellent code examples. We highly recommend both sites to deepen your experience, and further your coding journey. We’re just hitting the basics here at 1SMARTchicken.