BIG BAD WOLF:
You can apply a style at 3 different levels:
1. tag level. Every tag of the matching type will have the defined style
2. class level. Every element specified as belonging to that class will have the defined style. In the CSS file these start with #
3. id level. The element with the specified id will have the defined style. In the CSS file these start with . (dot)

The buttons and text boxes should all have identical classes, since you want to render them identically (same colours, font, border, etc). In this particular case it's hard to do it at tag style because usually they all share the tag "input". What you want is to use the id of the submit button and add some more styling to it.