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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                .poster
	- var r = 0
	while r < 5
		.row
			- var i = 0
			while i < 10
				.invader
				-i++
			-r++
			
	h1.game-over Game Over, Man!
	
	h2.aliens Aliens
!

CSS 

              
                $color-a: #c3bfad;
$color-b: rgba(#222, 0);
$color-c: #455528;

body {
	background: #222;
	font-size: 8px;
}

.poster{
	background: linear-gradient($color-c, darken($color-c, 15));
	border: 5em solid $color-a;
	margin: 20em auto;
	padding: 25em 5em 10em;
	width: 132em;
}

.row{
	display: block;
	height: 10em;
	width: 100%;
	
	&:nth-child(even){
		
		.invader{
			animation-delay: .5s;
		}
	}
}

.invader{
	background: rgba($color-a,0);
	display: inline;
	float: left;
	height: 1em;
	margin-right: 12em;
	margin-bottom: 10em;
	width: 1em;
		
	
	
	animation: pulse 1s infinite;
	
	&:nth-child(even){
		
		
		
	}
}

@keyframes pulse {
  0%,49.999%,100% {
    box-shadow: 
			2em 0em 0 $color-b, 3em 0em 0 $color-b, 4em 0em 0 $color-a, 5em 0em 0 $color-b, 6em 0em 0 $color-b, 7em 0em 0 $color-b, 8em 0em 0 $color-b, 9em 0em 0 $color-b, 10em 0em 0  $color-a, 11em 0em 0 $color-b, 12em 0em 0 $color-b,
			2em 1em 0 $color-b, 3em 1em 0 $color-b, 4em 1em 0 $color-b, 5em 1em 0 $color-a, 6em 1em 0 $color-b, 7em 1em 0 $color-b, 8em 1em 0 $color-b, 9em 1em 0 $color-a, 10em 1em 0  $color-b, 11em 1em 0 $color-b, 12em 1em 0 $color-b,
			2em 2em 0 $color-b, 3em 2em 0 $color-b, 4em 2em 0 $color-a, 5em 2em 0 $color-a, 6em 2em 0 $color-a, 7em 2em 0 $color-a, 8em 2em 0 $color-a, 9em 2em 0 $color-a, 10em 2em 0  $color-a, 11em 2em 0 $color-b, 12em 2em 0 $color-b,		
			2em 3em 0 $color-b, 3em 3em 0 $color-a, 4em 3em 0 $color-a, 5em 3em 0 $color-b, 6em 3em 0 $color-a, 7em 3em 0 $color-a, 8em 3em 0 $color-a, 9em 3em 0 $color-b, 10em 3em 0  $color-a, 11em 3em 0 $color-a, 12em 3em 0 $color-b,
			2em 4em 0 $color-a, 3em 4em 0 $color-a, 4em 4em 0 $color-a, 5em 4em 0 $color-a, 6em 4em 0 $color-a, 7em 4em 0 $color-a, 8em 4em 0 $color-a, 9em 4em 0 $color-a, 10em 4em 0  $color-a, 11em 4em 0 $color-a, 12em 4em 0 $color-a,		
			2em 5em 0 $color-a, 3em 5em 0 $color-b, 4em 5em 0 $color-a, 5em 5em 0 $color-a, 6em 5em 0 $color-a, 7em 5em 0 $color-a, 8em 5em 0 $color-a, 9em 5em 0 $color-a, 10em 5em 0  $color-a, 11em 5em 0 $color-b, 12em 5em 0 $color-a,			
			2em 6em 0 $color-a, 3em 6em 0 $color-b, 4em 6em 0 $color-a, 5em 6em 0 $color-b, 6em 6em 0 $color-b, 7em 6em 0 $color-b, 8em 6em 0 $color-b, 9em 6em 0 $color-b, 10em 6em 0  $color-a, 11em 6em 0 $color-b, 12em 6em 0 $color-a,
			2em 7em 0 $color-b, 3em 7em 0 $color-b, 4em 7em 0 $color-b, 5em 7em 0 $color-a, 6em 7em 0 $color-a, 7em 7em 0 $color-b, 8em 7em 0 $color-a, 9em 7em 0 $color-a, 10em 7em 0  $color-b, 11em 7em 0 $color-b, 12em 7em 0 $color-b;
  }
	
  50%,99.999% {
		box-shadow: 
			2em 0em 0 $color-b, 3em 0em 0 $color-b, 4em 0em 0 $color-a, 5em 0em 0 $color-b, 6em 0em 0 $color-b, 7em 0em 0 $color-b, 8em 0em 0 $color-b, 9em 0em 0 $color-b, 10em 0em 0  $color-a, 11em 0em 0 $color-b, 12em 0em 0 $color-b,
			2em 1em 0 $color-b, 3em 1em 0 $color-b, 4em 1em 0 $color-b, 5em 1em 0 $color-a, 6em 1em 0 $color-b, 7em 1em 0 $color-b, 8em 1em 0 $color-b, 9em 1em 0 $color-a, 10em 1em 0  $color-b, 11em 1em 0 $color-b, 12em 1em 0 $color-b,
			2em 2em 0 $color-a, 3em 2em 0 $color-b, 4em 2em 0 $color-a, 5em 2em 0 $color-a, 6em 2em 0 $color-a, 7em 2em 0 $color-a, 8em 2em 0 $color-a, 9em 2em 0 $color-a, 10em 2em 0  $color-a, 11em 2em 0 $color-b, 12em 2em 0 $color-a,		
			2em 3em 0 $color-a, 3em 3em 0 $color-a, 4em 3em 0 $color-a, 5em 3em 0 $color-b, 6em 3em 0 $color-a, 7em 3em 0 $color-a, 8em 3em 0 $color-a, 9em 3em 0 $color-b, 10em 3em 0  $color-a, 11em 3em 0 $color-a, 12em 3em 0 $color-a,
			2em 4em 0 $color-a, 3em 4em 0 $color-a, 4em 4em 0 $color-a, 5em 4em 0 $color-a, 6em 4em 0 $color-a, 7em 4em 0 $color-a, 8em 4em 0 $color-a, 9em 4em 0 $color-a, 10em 4em 0  $color-a, 11em 4em 0 $color-a, 12em 4em 0 $color-a,		
			2em 5em 0 $color-b, 3em 5em 0 $color-a, 4em 5em 0 $color-a, 5em 5em 0 $color-a, 6em 5em 0 $color-a, 7em 5em 0 $color-a, 8em 5em 0 $color-a, 9em 5em 0 $color-a, 10em 5em 0  $color-a, 11em 5em 0 $color-a, 12em 5em 0 $color-b,			
			2em 6em 0 $color-b, 3em 6em 0 $color-b, 4em 6em 0 $color-a, 5em 6em 0 $color-b, 6em 6em 0 $color-b, 7em 6em 0 $color-b, 8em 6em 0 $color-b, 9em 6em 0 $color-b, 10em 6em 0  $color-a, 11em 6em 0 $color-b, 12em 6em 0 $color-b,
			2em 7em 0 $color-b, 3em 7em 0 $color-a, 4em 7em 0 $color-b, 5em 7em 0 $color-b, 6em 7em 0 $color-b, 7em 7em 0 $color-b, 8em 7em 0 $color-b, 9em 7em 0 $color-b, 10em 7em 0  $color-b, 11em 7em 0 $color-a, 12em 7em 0 $color-b;
  }
}

.game-over{
	border: .2em solid $color-a;
	color: $color-a;
	font: 400 5em/2.65em 'Press Start 2P', cursive;
	height:2.5em;
	margin: 5em auto 15em;
	text-align: center;
	text-transform: uppercase;
	width: 16em;
}

.aliens{
	color: $color-a;
	font: 400 25em/1em 'Six Caps', sans-serif;
	margin: 0 0 0 .5em;
	text-align: center;
	letter-spacing: .5em;
	text-transform: uppercase;
}
!

JS 

              
                // based off http://pin.it/nWSBil_
!
999px

Console