1) hide header and footer
2) hide Back button
3) hide ID field
4) change or hide "table details" header
5) add custom background image
6) add some html before form
I'v add hook file (tablename.php) and ad some code to "function tablename_header" like this:
echo "<br/><br/><br/><br/>NEW HEADER";
echo "<body style='background-color:pink'>";
but don't know how to add some custom CSS to make all changes I need

CSS is my natural envinmet so it would be great to add some code like: diplay:none

Need some tip from pro.
Thank you in advance.
Regards Greg