Adding a border to a box

I created a text box, then I added some classes to style a rounded corner, shaded box with 3 columns. I added a border to the right. The last column also has a right border, and I understand why, but I can’t think of another way of doing it without using tables. Can someone help make a better box with rounded corners and 3 columns with a border dividing the two middle sections?

Quick CSS code:

.sb-container {
    border: 2px solid #000 ;
    border-radius: 20px ;
    padding: 20px ;
    background-color: #E3E3E3;
    color: #79afdd ;
    width: 760px ;
    height:200px;
    margin-left: auto ;
    margin-right: auto ;
}
.sb-container div {
    height: auto;
    border-right: 1px #47aa42 solid;
}
.sb-header {
    text-align: center;
}
.sb-column-left {
    width: 28%;
    /* left: 0; */
    background: #E3E3E3;
    position: absolute;
     padding-right: 0px;
}
.sb-column-center {
    width: 28%;
    background: #E3E3E3;
    margin-left: 29%;
    position: absolute;
    padding-right: 5px;
}
.sb-column-right {
    width: 28%;
    margin-left:58%;
    position: absolute;
    background: #E3E3E3;
    padding-right: 5px;
}

Code in text box:

<div class="sb-container">
<h3 style="text-align: center;"><span style="color: #47aa42;">QUICK FACTS</span></h3>
<div class="sb-column-left">FDA Class II clearance for use in active patient monitoring and primary and secondary Alarm Management <a title="Cardiopulmonary Corp. Receives Additional FDA 510(k) Class II Clearance Broadening Bernoulli® Enterprise’s Indications for Use with Medical Devices" href="http://tsgaz.net/bernoulli/cardiopulmonary-corp-receives-additional-fda-510k-class-ii-clearance-broadening-bernoulli-enterprises-indications-for-use-with-medical-devices/">>></a></div>
<div class="sb-column-center">Top-rated in customer satisfaction with reporting and analytics in KLAS Alarm Management Report 2014<a title="Performance Score" href="http://tsgaz.net/bernoulli/solutions/alarm-management#performance">>></a></div>
<div class="sb-column-right">Overall performance score of 90.1 from healthcare providers in KLAS Alarm Management Report 2014 <a title="Performance Score" href="http://tsgaz.net/bernoulli/solutions/alarm-management#performance">>></a></div>
</div>

http://tsgaz.net/bernoulli/solutions/medical-device-integration/

Thanks for any help you can give.

-Fred