Add support for sugarss

[vyorkin]

I mean postcss/sugarss – Indent-based CSS syntax for PostCSS.

for sy I currently use this: https://github.com/hhsnopek/vim-sugarss

[ap]

I’ll take a look. You can make this easier for me by providing me an example file in the style of the tests/example.* files, with a few examples of all the relevant syntax features in it, but I’ll look into it either way.

[ap]

So based on the README at postcss/sugarss I pasted the following into tests/example.sss:

a
  color: blue

.multiline,
.selector
  box-shadow: 1px 0 9px rgba(0, 0, 0, .4),
              1px 0 3px rgba(0, 0, 0, .6)

.one
  background: linear-gradient(rgba(0, 0, 0, 0), black)
              linear-gradient(red, rgba(255, 0, 0, 0))

.two
  background:
    linear-gradient(rgba(0, 0, 0, 0), black)
    linear-gradient(red, rgba(255, 0, 0, 0))

(Note to self: need a comment or two in there…)

With hhsnopek/vim-sugarss installed, opening that file and saying set syntax? gives me sugarss, which is evidently on the right track.

Except… it doesn’t really syntax-highlight the file usefully:

Is something wrong with my setup?