- Bugs - Good reference site: Position Is Everything Get margin when no border Problem: A div seems to have a margin when it doesn’t have a border. Giving it a 1px border and the margin disappears.
- Drop-down menu being hidden - If you get a drop-down menu that’s being hidden behind some content, make sure that all elements surrounding the menu have overflow:visible set and that the menu’s z-index is larger than the elements it need to appear over. E.g. I once wor...
- Accessible hiding content with CSS - Using display:none can also hide content from screen readers. If you do this, best use visibility:hidden as well, to ensure consistent behaviour in all readers. .hide{ display:none; visibility:hidden; } To hide from visual display but not screen...
- Consistent margins with CSS - Adjacent margins will collapse. CSS tutorial - Margin Collapsing Collapsing Margins In order to have consistent gaps around the edges of a content area you need to ensure the content area has a margin so that it collapses with any contained con...

