CVV

gistfile1.txt

$body.on('input', '#cvv', function(){
  $('#cvv-fake').val(new Array(this.value.length + 1).join('*'));
});

<div class="form-group relative">
	<label for="cvv" class="sr-only">CVV</label>
	<input type="cvv" id="cvv-fake" class="form-control" name="cvv"
	   autocomplete="off" placeholder="CVV" title="Card CVV (XXX)"
	   maxlength="3" value="" tabindex="-1"/>
	<input data-bind="value: cvv" type="cvv" id="cvv" class="form-control" name="cvv"
	   autocomplete="off" placeholder="CVV" title="Card CVV (XXX)"
	   required pattern="\d{3}" maxlength="3" value=""/>
</div>

input#cvv{
  position: absolute;
  top: 0;
  opacity: 0;
}