Read more about this plugin on iCheck's website.
<div class="form-group form-icheck">
<input type="radio" class="form-check-input iCheck-square-blue" name="" id="" value="" aria-label="Input Radio" aria-checked="false">
<label class="form-check-label" for="">Label</label>
</div>
<!-- CHECKED ---------->
<input type="radio" class="form-check-input iCheck-square-blue" name="" id="" value="" aria-label="Input Radio" aria-checked="true" checked>
<!-- CHECKED DISABLED ---------->
<input type="radio" class="form-check-input iCheck-square-blue" name="" id="" value="" aria-label="Input Radio" aria-checked="true" checked disabled>
<!-- DISABLED ---------->
<input type="radio" class="form-check-input iCheck-square-blue" name="" id="" value="" aria-label="Input Radio" aria-checked="false" disabled>
<!-- SUCCESS ---------->
<div class="form-group form-icheck is-valid">
<input type="radio" class="form-check-input iCheck-square-blue" name="" id="" value="" aria-label="Input Radio" aria-checked="true" checked>
<label class="form-check-label" for="">Label</label>
</div>
<!-- ERROR ---------->
<div class="form-group form-icheck is-invalid">
<input type="radio" class="form-check-input iCheck-square-blue" name="" id="" value="" aria-label="Input Radio" aria-checked="false">
<label class="form-check-label" for="">Label</label>
</div>
<!-- JAVASCRIPT ---------->
<script type="text/javascript" src="/scripts/common/js/icheck-1.0.2/icheck.min.js"></script>
<script type="text/javascript" src="/scripts/common/js/icheck-1.0.2/icheck-init.js"></script>