When a line in my CSS file appears to be too long (typically a property followed by a bunch of values), I want to split them in to several new lines like this (sorry for my low reputation):

<https://i.stack.imgur.com/bxXvv.png>

But I have to manually enter spaces before the lines to achieve that. In reality, when I hit TAB with my cursor on the `url` line, what I get is this:

<https://i.stack.imgur.com/r4nxa.png>

The worst thing is that, after manually inserting the spaces, when I hit TAB again on the same line, it goes back to the ugly format due to `indent-region`.

This is not a significant issue but it really pains me and I really hope we can have a decent solution here. Thanks in advance!

M-x version:

```
GNU Emacs 25.1.1 (x86_64-apple-darwin16.1.0, NS appkit-1504.60 Version 10.12.1 (Build 16B2555)) of 2016-11-27

```

EDIT:
Also tried web-mode for css files and xah-css-mode. None of them worked out.