CSS Tips

1. Width must be set in Opera. Otherwise, the padding, margin settings will not affect. and the content maybe mass up.
2. Set text-align to block display mode take no effect in Opera, Firefox unless the contained content's margin set to auto.
3. PNG image multiple browser support solution:

.PngImg{
background: url(someImg.png) no-repeat;
background: expression("none");
FILTER: progid:DXImageTransform.Microsoft.AlphaImageLoader
( src=someImg.png, sizingmethod=crop);
}