3.5 #Forms.Option Radio Option Radio
Add .cs inside .cs-checkbox to <input type="radio"> elements to apply the styles.
Example
Markup
<div class="cs-checkbox">
<label>
<input type="radio" class="cs" name="radio">
<span class="lbl">Member</span>
</label>
<label>
<input type="radio" class="cs" name="radio" checked>
<span class="lbl">Admin</span>
</label>
</div>
Source:
3_Form/forms.less
, line 88