SO fiddle

Test Fiddle mainly for SO Questions

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/overcast/jquery-ui.css">
<input type="radio" name="option_layout" value="0" checked="checked" />
<input type="radio" name="option_layout" value="1" />

<div class="group">
    Group Div
</div>

CSS

.group { height: 100px; }
.group_vert { border: solid 1px red; }

JavaScript

$("input[name='option_layout']").change(function() {
  $(".group").toggleClass("group_vert", $(this).val() == "1");
});