ucs

Animations

Follow this guide to learn how to add an animation to a website using the CSS Animations!

Click here for an in-depth introduction to the concept.

Setup

The setup for this concept will be fairly similar to the other concepts.

1. Click here to go to the Starter project
2. Open the index.html file for editing
3. Add a class attribute to the second <p> element that says “Style this paragraph…”
4. Set the class to be update
5. Find the <style></style> element
6. Create a new ruleset to style the paragraph by its class
   • Use .update as the selector
   • After the selector, add curly brackets ({ and })

At this point, the added code should look something like this:

HTML

<p class="update">Style this paragraph...</p>

CSS

.update {

}

The project should be ready for styling.

Defining an Animation with Keyframes

When animating using CSS, the styles are defined at certain keyframes. In animation and filmmaking, a keyframe is a drawing or shot that defines the starting and ending points of a smooth transition.

In CSS, these keyframes represent the styles of an element at a given point in time, during the animation cycle.

The goal for this animation will be to constantly transition from orange to green.

To make the color orange at the very beginning of the animation (or, 0% of the way through), the keyframe would look like a normal CSS ruleset, but with 0% as the selector.

Open up the index.html file for editing, and make some more space at the top of the <style></style>. Add this code to define the first frame of the animation:

0% {
  color: orange;
}

Next, to make the color green at the end of the animation (i.e., 100% of the way through), add the following ruleset under the first one:

100% {
  color: green;
}

Now, all that’s left is to put these two keyframes together is a @keyframes ruleset that includes both frames. A keyframes ruleset consists of:

• @keyframes
• animation name
• curly brackets ({})
• frame rulesets within { and }

So, the 0% and 100% ruleset need to go inside of the @keyframes ruleset. We’ll call this animation pulse. At the very top of the <style></style> element, open up the definition with:

@keyframes pulse {

For clarity, indent the 0% and 100% rulesets. Then, under both of those rulesets, close out the @keyframes with a }!

The whole animation definition should look something like this:

@keyframes pulse {
  0% {
    color: orange;
  }

  100% {
    color: green;
  }
}

Using an Animation on an HTML Element

After defining an animation’s keyframes, it must be applied to an element to take effect. Apply this animation to the <p class="update> paragraph by creating a declaration that points to the pulse animation.

Note that there are many options for the animation property:

• animation-duration configures the length of time that an animation should take to complete one cycle
• animation-iteration-count configures the number of times the animation should repeat
• animation-timing-function configures the timing of the animation
• animation-direction configures whether or not the animation should alternate direction on each run through the sequence
• animation-name specifies the name of the @keyframes ruleset describing the animation’s keyframes

For the purposes of this walkthrough, all of them can be combined into one declaration, with the following format:

animation: animation-duration animation-iteration-count animation-timing-function animation-direction animation-name;

1. Within the <style></style> element, find the .update ruleset
2. Within the ruleset (between { and }), create a new declaration with a property of animation
3. To put together all configuration for the animation, list each value separated by a space:
   • 1s so the animation takes one second to complete
   • infinite so the animation goes on forever
   • linear so the animation happens smoothly
   • alternate so the animation goes smoothly between orange and green
   • pulse so the animation uses the keyframes specified by the pulse animation

The ruleset in the <style></style> for the <p class="update"> paragraph should look something like this:

.update {
  animation: 1s infinite linear alternate pulse;
}

Load up the page, and make sure the text changes color continuously!

Next Steps

This was just a small example of what’s possible with CSS animations. You can animate any CSS property, and create any number of keyframes! Click here for to dive deeper into everything you can do.