The documentation of the font-family css-properties says that

The names of the font family that contain spaces must be quoted.

However, an example is given in which the name of the font family with spaces is not enclosed in quotes:

 font-family: Gill Sans Extrabold, sans-serif;

As a result, spaces without quotes are allowed or not?

    2 answers 2

    The World Wide Web Consortium (W3C) website says that:

    It is a white space for you to use.

    those. To avoid errors, it is recommended that you quote names of font families that contain spaces, numbers, or punctuation other than a hyphen.

    If you don’t install it, in most browsers it’s a ride, but there are different cases and different operating systems, so I recommend setting it up.

    https://www.w3.org/TR/css-fonts-3/

    ps: I always quote the names of font families containing spaces

      Open the specification and see:

      Font family names other than generic families. It must be escaped in unquoted font family names ..........

      In short: if the names contain spaces, numbers, punctuation marks or keywords (for example: "inherit" and others), then it is recommended to take the name of the font in double quotes to avoid errors.