CSS character escape sequences

This content originally appeared on Mathias Bynens and was authored by Mathias

When writing CSS for markup with weird class or id attribute values, you need to consider some rules. For example, you can’t just use ## { color: #f00; } to target the element with id="#". Instead, you’ll have to escape the weird characters (in this case, the second #). Doing so will cancel the meaning of special CSS characters and allows you to refer to characters you cannot easily type out, like crazy Unicode symbols.

This content originally appeared on Mathias Bynens and was authored by Mathias