As the topic says I want to create a container that will be semi-transparent with a degrade color and with round corners.
What is the best way to do it (in a way that it is fully browser compatible)?
Than you very much.
It depends on whether or not you absolutely have to have it in all browsers. You can use some CSS3 properties, which work in Firefox, Safari and others, but doesn't work in IE. Otherwise, you'll have to do either some hacks or a bunch of extra divs or other elements.
Check out http://www.css3.info/preview/rounded-border/
I usually do a semi-transparent GIF as the background image, but it doesn't work in all browsers.