Spot the difference - one button shows, one doesn't

[dr_smith]

Hi,

I've got two sites bolted together to look like one. One is a WordPress CMS, the other a .NET application. For the page templates they use mostly the same HTML and CSS.

I have a simple search box (top right) with a text input and a submit input. The submit button text ('GO') shows up in the WordPress template but not in the .NET app. As far as I can tell the HTML rendered and CSS is the same for both. Am I missing something?

WordPress CMS site
http://www.coleg-powys.ac.uk/

.NET application
http://www.coleg-powys.ac.uk/curriculum/

I realise that one site is written in PHP and the other ASP.NET but that shoudn't make any difference to the appearance on screen if the basic HTML and CSS is the same, should it?

Any ideas greatly appreciated.