Responsive divs not sitting side by side

I have a zencart and I want to have a 2 responsive divs inside a parent div.
At the moment they are responsive but on a pc screen the content sits on top of the buttons instead of side by side.
See here http://www.kinectwebdesign.com/ingleburncashexchange/
I have an attached an image of what it currently looks like.

<div id="defineDiv">
  <div id="defineMainLeft">
TEXT IS IN THIS DIV blah blah.
</div>
  <div id="defineMainRight">
  <a href="javascript:void(0);" class="service_item" alt="" data-animated="bounceIn">
<div class="icon_block icon1"></div>
<h4>Hock Your Car</h4>
  </a>
  <a href="javascript:void(0);" class="service_item" alt="" data-animated="bounceIn">
<div class="icon_block icon2"></div>
<h4>Items for Sale</h4>
  </a>
  <a href="javascript:void(0);" class="service_item" alt="" data-animated="bounceIn">
<div class="icon_block icon3"></div>
<h4>Sell Your Goods</h4>
  </a>
  <a href="javascript:void(0);" class="service_item" alt="" data-animated="bounceIn">
<div class="icon_block icon4"></div>
<h4>Cash Loans</h4>
  </a>
  </div>
</div>

Code (markup):

.defineDiv,
        .defineMainLeft,
        .defineMainRight {
            //change the box model for simplicity
            -webkit-box-sizing: border-box;
               -moz-box-sizing: border-box;
                    box-sizing: border-box;
        }
       
        .defineDiv {
            font-size: 1em;
            padding: 1.5em;
            width: 100%;
        }
       
        .mainContent,
        .defineMainRight {
            display: inline-block;
            vertical-align: top;
            width: 100%;
        }
       
        @media (min-width: 700px) {
       
            .defineMainLeft {
                margin-right: 5%;
                width: 60%;
            }
       
            .defineMainRight { width: 35%; }
        }

Code (CSS):

 

This gave me the solution. http://www.webdesignerdepot.com/2014/07/the-secret-to-designing-website-layouts-without-css-floats/
I think I had one of my divs in the html missing or not named correctly.
Hope it helps someone.