CSS to edit Zip Code

[LibbyCat50]

Hi, I'm not very good with CSS, and have been trying to edit the terminology "Zip Code" to "Postcode". Using my browser's inspector I have been able to edit the code to display "Postcode", but when I paste that into the custom CSS field in Advanced Options I'm not getting the change I need. Can someone please help be out? Here is the code I wish to use:

<div class="ec_cart_input_right_half">
<label for="ec_cart_billing_zip">Postcode*</label>
<input type="text" name="ec_cart_billing_zip" id="ec_cart_billing_zip" class="ec_cart_billing_input_text" value=""> <div class="ec_cart_error_row" id="ec_cart_billing_zip_error">
Please enter your Postcode </div>
</div>

Thanks very much in advance. Cheryl

[LibbyCat50]

Got it worked out now. No help needed.