Looking for suggestions on how to style internal and external links.
External links will open a new page (or tab); and there are two types of internal links: a sub-menu type link; and one that opens a popup pane.
I've road-tested a couple of ideas and the users have found both a bit confusing: underlining all links, and giving different backgrounds to each type; and underlining just the external links and giving both internals the same background.
Also tried to delve into Wikipedia to find the origin of that little diagonal-arrow-thingy used on external links.
Are there any well-established conventions? Things you know work with viewers of varying savviness?
I'm always hesitant to change from blue and underlined, perhaps with the colours tweaked.
Normally attribute selectors are used for external links, either with a rel="external" in the link or something like [href^=http://] if you use http://something.com for all external links. However, if you then use pseudo-content classes to generate an image, that won't work in IE 7, so a background image would probably be best.
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