Question

On my site http://goo.gl/BcJtC section “about us” I’d like a thin grey border on the right side of my activity-left div, to make a separation with activity-right div.
Unfortunately with my current code it doesn’t work. Any idea?
Thanks

HTML code:

<div class="section" id="plan-activite">
   <div id="activity-container">
      <div id="activity-left"><span class="activity-title">About Us</span><br /><img src="images/planet-water.jpg" class="activity-planet" alt="Picture" /></div>
      <div id="activity-right"><p><span class="activity-conclusion">XYZ, khkhkhk, ren natur</span></p><br /><p>XXZ AS was founded 2011sdqsd.</p><br/>
      </div>
   </div>
</div><!--END page3-->

CSS code:

#activity-container {
    width:90%;
    background-color:#FFFFFF;
    Height:400px;
    margin-left: auto;
    margin-right: auto;
    opacity:0.95;
    filter:alpha(opacity=95); /* For IE8 and earlier */
    border: 1px solid #efefef;
    background: #fff;
    -webkit-box-shadow: 0 1px 4px rgba(0, 0, 0, 0.27), 0 0 40px rgba(0, 0, 0, 0.06) inset;
    -moz-box-shadow: 0 1px 4px rgba(0, 0, 0, 0.27), 0 0 40px rgba(0, 0, 0, 0.06) inset; 
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.27), 0 0 40px rgba(0, 0, 0, 0.06) inset;
}
#activity-left {
    color:#000;
    margin: 0 auto; 
    border-style:solid;
    border-right-color:#666;
    padding:15px;
    width: 30%; 
    float: left;
    position: relative; 
}
#activity-right { 
    font:12px 'Open Sans', "Helvetica Neue", Helvetica, Arial, "Lucida Grande", sans-serif;
    font-weight:400;
    margin: O auto; 
    padding:15px;
    color:#000;
    width: 60%; 
    float: left;
    position: relative; 
    text-align:justify;
    -moz-column-count: 1;
    -moz-column-gap: 1.5em;
    -moz-column-rule: 1px solid #c4c8cc;
    -webkit-column-count: 1;
    -webkit-column-gap: 1.5em;
    -webkit-column-rule: 1px solid #c4c8cc;
}
.activity-planet {
    text-align:center;
    margin-top:20px;
    margin-left:20px;
}

Answer 1

Add border: 1px solid #000 to #activity-left. It works for me.

Although I would do border-left: 1px solid #000 for #activity-right as this will extend all the way down.