There is no official HTML markup for CSS font icons, but 2 markups are widely used. Both markups can be used in block elements like the anchor tag <a> or use span elements <span>. That way, it’s on you what to use for font based icons.

For pages using Asciidoc for the source, a easier solution is available by using markups from Asciidoc.

Two styles are available for country flag icons: rectangle rectangle and squared squared. The default style is rectangle 4:3 of the icon. For more compact placement, all icons can be used in a squared format 1:1.

For more specific placement, or to place emphasis on, all icons can be specified in different sizes by the optional size parameter size.

See with the following what sizes are available.

For better placement, additional CSS styles called modifiers can be specified like so:

Germany, rectangle style
Germany, square style

Find all flags available in alphabetical order.