yes for all 3.. but the difference is most readily seen in the reverse order of power.. that is you'll see the diff in external stylesheets EASY EASY.. embedded a little less easy and in-lines almost never, but still possible.
Important to note is that it's not the type of stylesheet that introduces the vulnerability its the way in which people write the diff stylesheets. For instance, people tend to forget about precedence in external sheets and drop their classes anywhere, whereas with inline classes they are forced to write what will be applied to the object.. so the rules of precedence become much more difficult to break.
For instance...
here's some of my code I tested it on... this is an externally linked sheet:
Code:
/* CSS Document */
a:link {
font-family: Verdana, Arial, Helvetica, sans-serif;
color: #0066FF;
text-decoration: none;
font-size: xx-small;
}
a:visited {
font-family: Verdana, Arial, Helvetica, sans-serif;
text-decoration: none;
font-size: xx-small;
color: #0066FF;
}
a:active {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: xx-small;
color: #006666;
}
a:hover {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: xx-small;
color: #FF6600;
text-decoration: underline;
}
the above displays all links a particular color, and all links are displayed without an underline. Now.. BECAUSE the hover class is LAST then ALL links will have an underline when you mouse over, however.....
Code:
a:link {
font-family: Verdana, Arial, Helvetica, sans-serif;
color: #0066FF;
text-decoration: none;
font-size: xx-small;
}
a:hover {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: xx-small;
color: #FF6600;
text-decoration: underline;
}
a:visited {
font-family: Verdana, Arial, Helvetica, sans-serif;
text-decoration: none;
font-size: xx-small;
color: #0066FF;
}
a:active {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: xx-small;
color: #006666;
}
Now the underline will only appear on links which are neither active nor visited... This weakness is seen just as evidently in linked and embedded CSS.
Try it. ;D