cursor pointer not showing up, chuck the following in your css...
cursor: pointer;

facebook does not seem to like the use of the filename screen.png

its actually much easier to hard code values as in...

Click Me

in javascript in facebook: getStyle('background-color')  may not return unless the style is inline.

Oh and type background-color without the hyphon and capitalized 'c' as in ... backgroundColor

Might help if this was actually documented somehwere
backgroundColor

Returning false (in javascript)should nullify the default
HTML behavior for whatever event just occurred on a page

Get document root with $_SERVER['DOCUMENT_ROOT']

To get the path to the current file use __FILE__
To find the directory it resides in use dirname()

So combined...
dirname(__FILE__) 

Useful for relative paths 

display html to the screen without rendering. with php function htmlentities()
to make it more legible convert line breaks to
with nl2br()

So example: nl2br(htmlentities($myHTML));
htmlentities