How to define the border bottom color is animatable in CSS?

CSS is a powerful tool that allows web developers to create engaging and interactive web experiences. One of the ways CSS used is to define the border bottom color of an element. While it may seem like a simple task, it is important to understand how the border bottom color can be animated for added effect.

In CSS, animation refers to the process of changing the style of an element over time. Animating the border bottom color of an element helps draw attention to it and make it more visually interesting. In order to make this effect, the border bottom color define as animatable.

To define the border bottom color as animatable in CSS, we first understand what makes a property animatable. An animatable property is one that can be changed gradually over time, allowing for smooth transitions and fluid movement. These properties are defined using specific syntax and can be modified using keyframes or transitions.

Animatable properties in CSS

Animatable properties are CSS properties that can be animated using transitions, animations, or keyframes. Some of the most commonly used animatable properties in CSS include −

  • Color − We can animate the color of text, backgrounds, borders, and other elements using the color property.

  • Opacity − The opacity property controls the transparency of anelement and is used to create fade-in and fade-out effects.

  • Transform − The transform property allows us to apply various visual transformations to an element.

  • Width and Height − We can animate the size of an element by changing its width and height properties.

  • Margin and Padding − The margin and padding properties can also be animated to create movement and flow on a web page.

  • Font-size − The font-size property is used to create text that increases or decreases over time.

  • Background-position − This property is used to animate the position of a background image.

  • Box-shadow − The box-shadow property is used to animate the shadow of an element.

  • Border-radius − The border-radius property is used to create animations that change the shape of an element over time.

These are just a few examples of the many animatable properties available in CSS.

In order to animate the border bottom color of an element in CSS, we use the border-bottom-color property. This property can be modified using keyframes, which allow us for precise control over the animation.


Here is an example of animated border bottom color.

<!DOCTYPE html>
      body { text-align: center; }
      .box {
         height: 80px;
         width: 60%;
         margin: auto;
         border-bottom: 12px solid black;
         border-top: 12px solid green;
         border-right: 12px solid blue;
         border-left: 12px solid black;
         border-bottom-color: red;
         animation: color-change 3s infinite;
      @keyframes color-change {
         0% {
            border-bottom-color: red;
         50% {
            border-bottom-color: orange;
         100% {
            border-bottom-color: yellow;
      <div class="box">Border Bottom animatable Example</div>

In this example, the border bottom color of the box will transition from red to orange to yellow in a repeating animation that lasts for 3 seconds.


Animating the border bottom color of an element adds visual interest and engagement to a website. By defining the element and the styles in HTML and CSS and using transitions or keyframes to create the animation, we can create dynamic and engaging web experiences that draw the eye.

Updated on: 16-Mar-2023


Kickstart Your Career

Get certified by completing the course

Get Started