Ahoy, front-end pirates! Welcome to the Chapter 3 of the Making of The Secret of Front-end Island saga: the Rising Smoke.

Front-end Island Rising Smoke

In the layout the smoke was composed by 5 gray circles at different opacity. Oh joy! I could avoid using images using markup and border-radius, and animate every smoke ball using CSS 3 only. Challenging, then funny. :)

Structure of the page

As explained in the previous post, I divided the site into many sections:

  • event
  • speakers
  • description
  • city
  • venue
  • cart
  • and so on…

The DOM path of the smoke parent element is the following:

#event > #horizon > #smoke

The smoke markup

By the layout, 5 balls of smoke are visible at the same time. To make a beautiful animation, I decided to double them. Here’s the markup for the 10 balls of smoke.

<div id="smoke">
	<span class="s0"></span>
	<span class="s1"></span>
	<span class="s2"></span>
	<span class="s3"></span>
	<span class="s4"></span>
	<span class="s5"></span>
	<span class="s6"></span>
	<span class="s7"></span>
	<span class="s8"></span>
	<span class="s9"></span>
</div>

The CSS 3 only animation

The smoke animation can perfectly be developed in CSS 3 only.

I used Modernizr to test whether the browser supports CSS 3 animations or not. Modernizr adds the cssanimations class if the browser supports animations, or the no-cssanimations if it doesn’t.

The disableAnimations class is toggled when the user presses the “disable animations” button on the page (maybe to save battery life).

So here’s the code:

/* Smoke container */
#smoke {
	position: absolute;
	z-index: 3;
	width: 1px; height: 160px;
	left: 50%; bottom: 116px;
}

/* No animations or animations disabled? Display a static smoke image */
.disableAnimations #smoke,
.no-cssanimations #smoke {
	width: 86px;
	margin-left: -25px;
	bottom: 146px;
	background: url('../img/smokeNoAni.png') no-repeat center bottom;
}

/* smoke balls */
.cssanimations #smoke span {
	display: block;
	position: absolute;
	bottom: -35px; left: 50%; margin-left:-20px;
	height: 0px; width: 0px;
	border: 35px solid #4b4b4b;
	border-radius: 35px;
	left: -14px; opacity: 0;
	transform: scale(0.2);
}

Until now, the smoke container is positioned and all the smoke balls are positioned to its bottom and scaled to 20%.

And here’s where the magic happens. I created two different animations, smokeL for the smoke balls which moved up and left, and smokeR for the smoke balls which moved up and right.

@keyframes smokeL {
	0%   { transform:scale(0.2) translate(0, 0) }
	10%  { opacity: 1; transform: scale(0.2) translate(0, -5px) }
	100% { opacity: 0; transform: scale(1) translate(-20px, -130px) }
}

@keyframes smokeR {
	0%   { transform:scale(0.2) translate(0, 0) }
	10%  { opacity: 1; transform: scale(0.2) translate(0, -5px) }
	100% { opacity: 0; transform: scale(1) translate(20px, -130px) }
}

Then I applied this two animations alternately to each smoke ball, with a total duration of 10 seconds, and a delay of 1 second more each.

Here’s how:

#smoke .s0 { animation: smokeL 10s 0s infinite }
#smoke .s1 { animation: smokeR 10s 1s infinite }
#smoke .s2 { animation: smokeL 10s 2s infinite }
#smoke .s3 { animation: smokeR 10s 3s infinite }
#smoke .s4 { animation: smokeL 10s 4s infinite }
#smoke .s5 { animation: smokeR 10s 5s infinite }
#smoke .s6 { animation: smokeL 10s 6s infinite }
#smoke .s7 { animation: smokeR 10s 7s infinite }
#smoke .s8 { animation: smokeL 10s 8s infinite }
#smoke .s9 { animation: smokeR 10s 9s infinite }

And that’s it! The smoke animation works perfectly on modern browsers!

Here’s the result:

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More to come!

Come back in the next few days to see the rest of the Making of The Treasure of Front-end Island saga!