The horizontal rule below should not be red. It should be green with (optionally) a thin red border.

Expected result (screenshot):

Image download support must be enabled

"Essentially, IE treats them [horizontal rules] as inline elements, while the others [browsers] treats them [horizontal rules] as block elements." coming from How do I style an hr?
<hr> is a block-level element, not an inline-element.

unknown or not available unknown or not available
The correct answer should be, must be block, not inline.

Valid HTML 4.01! CSS compliant