This explains CSS escaping pretty well: https://mathiasbynens.be/notes/css-escapes https://mathiasbynens.be/notes/css-escapes \37 is the escaped hexadecimal nu

This explains CSS escaping pretty well: https://mathiasbynens.be/notes/css-escapes https://mathiasbynens.be/notes/css-escapes \37 is the escaped hexadecimal number 0x37 == the ASCII character '7' The whitespace after the escaped character is "eaten" (the whitespace indicates the end of the escape sequence) 0 is '0' \% is '%' (update: fixed \37 == '7')