First, here is what we will build. Set your timer!

Here’s the DEMO we’ll build.

Does this look familiar?

If yes, that’s because you’ve seen this somewhere — Slack!

Let’s learn a few things by recreating this with just CSS and some good ol’ HTML.

If you’re excited about writing some code, get on Codepen and create a new pen.

Now, let’s go!

1. The Markup

The markup required for this is quite simple. Here it is:

<section class="loading">
For new sidebar colors, click your workspace name, then     Preferences > Sidebar > Theme
<span class="loading__author"> - Your friends at Slack</span>;    <span class="loading__anim"></span>
</section>

Simple, huh?

If you’re not sure why the class names have weird dashes, I explained the reason behind that in this article.

There’s a bunch of text, and a .loading__anim span to “impersonate” the animated icon.

The result of this is the simple view below.

Not so bad, huh?

2. Center the Content

The result isn’t the prettiest of stuff to behold. Let’s have the entire .loadingsection element entered in the page.

body {  display: flex;  justify-content: center;  align-items: center;  min-height: 100vh;}
Now centered!

Looking better?

3. Style the Loading text

I know. We will get to the animated stuff soon. For now, let’s style the .loading text to look a lot better.

.loading {  max-width: 50%;  line-height: 1.4;  font-size: 1.2rem;  font-weight: bold;  text-align: center;}

4. Style the author text to look slightly different.

.loading__author {  font-weight: normal;  font-size: 0.9rem;  color: rgba(189,189,189 ,1);  margin: 0.6rem 0 2rem 0;  display: block;}

There you go!

5. Create the animated loader

The much-anticipated step is here. This is going to be the longest of the steps, because I’ll be spending some time to make sure you understand how it works.

If you get stuck, drop a comment and I’ll be happy to help.

Hey, have a look at the loader again.

You’ll notice that half of its stroke is blue and the other half is grey. Okay, that’s sorted out. Also, HTML elements aren’t rounded by default. Everything is a box element. The first real challenge will be how to give the .loading__anim element half borders.

Don’t worry if you don’t understand this yet. I’ll come back to it.

First, let’s sort out the dimensions of the loader.

.loading__anim {  width: 35px;  height: 35px; }

Right now, the loader is on the same line as the text. That’s because it is a span element which happens to be an HTML inline element.

Let’s make sure the loader seats on another line, that is it begins on another line as opposed to the default behavior of inline elements.

.loading__anim {   width: 35px;   height: 35px;   display: inline-block;  }

Finally, let’s make sure the loader has some border set.

.loading__anim {   width: 35px;   height: 35px;   display: inline-block;   border: 5px solid rgba(189,189,189 ,0.25);  }

This will give a greyish 5px border around the element.

Now, here’s the result of that.

You see the grey borders, right?

Not so great — yet. Let’s make this even better.

An element has four sides, top, bottom,left, and right

The border declaration we set earlier was applied to all the sides of the element.

To create the loader, we need two sides of the element to have different colors.

It doesn’t matter what sides you choose. I have used the top and left sides below

.loading__anim {  width: 35px;  height: 35px;  display: inline-block;  border: 5px solid rgba(189,189,189 ,0.25);  border-left-color: rgba(3,155,229 ,1);  border-top-color: rgba(3,155,229 ,1);  }

Now, the left and top sides will have a blueish color for their borders. Here’s the result of that:

hmmmm. looking nice.

We’re getting somewhere!

The loader is round, NOT rectangular. Let’s change this by giving the .loader__anim element a border-radius of 50%

Now we have this:

Not so bad, huh?

The final step is to animate this.

@keyframes rotate { to {  transform: rotate(1turn) }}

Hopefully, you have an idea of how CSS animations work. 1turn is equal to 360deg , that is a complete turn rotates 360 degrees.

And apply it like this:

animation: rotate 600ms infinite linear;

Yo! We did it. Does that all make sense?

By the way, see the result below:

lo hicimos! (Spanish)

Pretty cool, huh?

If any of the steps confused you, drop a comment and I’ll be happy to help.

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