Untitled

dabblet.css

.container {
  position: relative;
  left: 100px;
  margin: 200px auto;
  width: 500px;
  height: 500px;
} 

.circle {
  position: absolute;
  display: inline-block; 
  height: 200px;
  width: 200px;
  border-radius: 50%;
  border: 1px solid #444;
}

.circle1{
  top: 100px;
  left: 75px;
  background: rgba(255, 0, 0, .2);
}

.circle2{
  background: rgba(0, 255, 0, .2);
}

.circle3{
  top: 100px;
  left:-75px;
  background: rgba(0, 0, 255, .2);
}

dabblet.html

<script src="http://code.jquery.com/jquery-1.9.1.js"></script>
<div class="container">
  <div class="circle circle1"> </div>
  <div class="circle circle2"> </div>
  <div class="circle circle3"> </div>
</div>

dabblet.js

// alert('Hello world!');

settings.json

{"view":"split-vertical","fontsize":"100","seethrough":"","prefixfree":"1","page":"css"}