I am trying to create 3 column home layout, in which center, left and right looks fine, but I am unable to create 2 slider division inside div class middle, I actually expect slider1 should come on top, but should be inside the class middle, and slider2 after slider1 inside class middle. 
As you can see here JSFIDDLE , slider2 and slider1 is not coming inside div class middle
This is my effort
HTML
<div id="content-container">
    <div class="middle">
          <div class="slider1"></div>
          <div class="slider2"></div>
   </div>
   <div class="left">
          <div></div>
          <div></div>
   </div>
   <div class="right">
          <div></div>
          <div></div>
   </div>
</div>
CSS
/* Container */
#content-container{
    background:white;
    margin-top:10px;
    margin-bottom:10px;
    height:600px;
}
/* follow container height*/
.left,.right,.middle{
    height:100%;
}
.left{
    float: left; 
    width: 23%; 
    border:1px solid red;
}
.right{
    float: right; 
    width: 23%; 
    border:1px solid red;
}
.middle{ 
     display: inline-block; 
     width: 53%; 
     border:1px solid red;
}
/* Sliders */
.slider1 { 
        height: 50px;
        border:1px solid green; 
}
.slider2 {  
        height:60px; 
        border:1px solid green;
}
Thank you