Das Styling von benutzerdefinierten Feldern wird nicht überall angezeigt

[JTLware]

In "Advanced Customer Data" I created 2 custom fields, they are displayed correctly without any problems, the problem I have is that I need to redesign the look of the fields a bit.

I added my styles in the file "custom_fields.tpl" and they are displayed correctly even on the checkout page "/Order Process?wk=1" but I also used these custom_fileds on another page "Register?Customer Group=2".

Why aren't the styles I added showing up there?
Please help!