In reply to Pedro50:
Same problem. Tried both Chrome and Safari. Here is the problem in the HTML:
The second div in the radio button section is currently:
<div class="radio radio-primary"><input id='q27a' class='radio' type='radio' name='q2' value="7A+" required="required" /> <label for='q27a'>7A+</label></div>
It should be:
<div class="radio radio-primary"><input id='q27a+' class='radio' type='radio' name='q2' value="7A+" required="required" /> <label for='q27a+'>7A+</label></div>
Two + missing.