Input disabled not greyed out in wordpress

Hello. I have always used an html document, working with a Google script, for a form. The input disabled option always greyed out the input text box for me until it was no longer disabled. I attempted to just add this form into a code module in a Wordpress site. While the input area is disabled, it is no longer greyed out. Do you have any advice on how to resolve this issue?

<div class="col-xs-12 col-md-3 col-lg-3">
                    <label for="ceProviders"><strong>Please list CE providers you have presented for.</strong></label><br />
                    <input type="text" placeholder="" id="ceProviders" name="ceProviders" style="border: 1px solid #00cdc8; width: 100%;" disabled  />