committed the following to trunk:
http://open.silverstripe.com/changeset/42730

refactored css and requirements: created more specific css-files to reduce side-effects and ease debugging, moved generic form-styling from cms/css/cms_*.css into sapphire/css/Form.css. ordered Requirement-inclusions in CMSMain/LeftAndMain to be more coherent (avoiding duplicate requirement-calls)

this means you get a lot of form-styling "for free" by including Form.css, and relying on the Requirements added by the used formfields, instead of tricking cms_right.css to apply to your markup, or copy&pasting everything.

Form.css isn't included by default in any form, but is there in case you need it.

IMPORTANT:
I've tried to come up with scenarios where you need to adapt legacy code once switching to the next release including these changes:
- custom requirements: if you relying on cms_right.css to contain all form-styling, you need to include sapphire/css/Form.ss now
- custom backend-modules with cleared requirements: just have a look at whats included in LeftAndMain/CMSMain now
- formfield-usage outside of cms: new css-requirements have been added to several formfields, which might affect the styling on your site. use Requirements::clear(<cssfile-path>) to undo those changes in your specific case.

in case you feel that other rules belong into the generic Form.css as well (or some are too cms-specific for Form.css), please discuss here - or patch on trunk :)

by the way: we still have project-specific Requirements in LeftAndMain::init() - i vaguely remember somebody working on a more flexible solution to inject Requirements, does anybody know specifics here?