should it have quotes or not in background image?

[mdo]

should it have quotes or not in background image?

[mdo]

This was fixed at some point.

[paulhirschi]

The official W3 spec has it in double quotes url("source.img") This is the convention I follow, and I see used most often.

[nhall]

I've tended to treat this like I do the trailing slash of self-closing tags.

Don't include a trailing slash in self-closing elements—the HTML5 spec says they're optional.

The W3C says these quotes are optional so I would rather omit all together.

[johannesnagl]

iirc, you need them, when you have spaces in the referenced file name. so it's always good to always use the quotes.

i think, in regard to this rule:
"Quote attribute values in selectors, e.g., input[type="text"]. They’re only optional in some cases, and it’s a good practice for consistency."

it should always be applied, when i recall the case with spaces correctly.

[hozefaj]

Whether using single quotes or double quotes, just being consistent across the project does the trick.

[Donneh]

You shouldn't have spaces in filenames though.