Alter input style when text entered using just CSS

Question

I am styling a page where I have only been given access to the CSS files.

I am looking to alter the style of an input element if it's value is not blank.

Here's what I have so far...

<input id="myInput" type="text" name="myInput" autocomplete="off" placeholder="Enter your Card Number">

and

input {
    font-style:italic;  
}

input:not([value='']) {
    font-style:normal;  
}

This doesn't work though as the text is never italicised.

Is it even possible to achieve this taking into consideration I can only edit the CSS file.?

Answer 1

Looks like you're using HTML5...if so just edit your PLACEHOLDER tag

::-webkit-input-placeholder {font-style: italic} /*Chrome */
:-moz-placeholder {font-style: italic} /*ff*/
:-ms-input-placeholder {font-style: italic} /*ie latest */

JSFIDDLE:

http://jsfiddle.net/Riskbreaker/wCff9/