yandex-ui/stylobate-islands — pull request #74 by doochik (2014-05-29 16:21:59+00:00)
Title: Fix for structure CSS minificator like cleancss

'promo-button' generated this code
```css
{
background-color: #000
background: linear-gradient(...)
}
```

cleancss removes 'background-color' in favour more complex 'background'