bar vertical

CSS:

       #mainDiv {
         height: 100px;
         width: 80px;
         position: relative;
         border-bottom: 2px solid #f51c40;
         background: #3beadc;
         }

       #borderLeft  {
         border-left: 2px solid #f51c40;
         position: absolute;
         top: 50%;
         bottom: 0;
         }
HTML:

<div id="mainDiv">
         <div id="borderLeft"></div>
</div><!--end mainDiv-->