Hello Roryt, Forum Members,
To minimize the differences of all elements in different browsers, you can add:
* {padding: 0px; margin: 0px} to your style sheet. This eliminates the default margins and padding for everything. Elements like for H1, h2..., <li> <input>, etc. have different styles in different browsers. This starts you off with a level playing field. You'll have to go back and add some margins and padding to elements you didn't have to style before however!

Peace