CodePen

HTML

            
              <ul>
  <li>
    <div id="a"></div>
    <div id="b"></div>
    <div id="c"></div>
    <div id="d"></div>
  </li>
</ul>
            
          
!

↑ Insert the most common viewport meta tag

CSS

            
              * {
  margin:0;
  padding:0;
  -webkit-box-sizing:border-box;
  box-sizing:border-box;
}

ul {
  list-style-type:none;
}

li {
  height:60px;
  width:100%;
  box-shadow:inset 0 0 3px green;
}

div {
  float:left;
  position:relative;
  box-shadow:inset 0 0 3px #111;
}

#a {
  height:60px;
  width:15%;
  background:rgba(255,0,0,0.6);
}

#b {
  height:30px;
  width:70%;
  background:rgba(224,178,27,0.6);
}

#c {
  height:30px;
  width:70%;
  background:rgba(0,255,0,0.6);
}

#d {
  height:60px;
  width:15%;
  margin-top:-30px;
  background:rgba(0,0,255,0.6);
}
            
          
!
? ?
? ?
Must be a valid URL.
+ add another resource
via CSS Lint

JS

            
              
            
          
!
Must be a valid URL.
+ add another resource
via JS Hint
Loading ..................