What you are trying to do can be simplified down to this.
$('input:text').bind('focus blur', function() {_x000D_
$(this).toggleClass('red');_x000D_
});
_x000D_
input{_x000D_
background:#FFFFEE;_x000D_
}_x000D_
.red{_x000D_
background-color:red;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>_x000D_
_x000D_
<form>_x000D_
<input class="calc_input" type="text" name="start_date" id="start_date" />_x000D_
<input class="calc_input" type="text" name="end_date" id="end_date" />_x000D_
<input class="calc_input" size="8" type="text" name="leap_year" id="leap_year" />_x000D_
</form>
_x000D_