it's [less](http://lesscss.org/features/), you can be module (i.e. put that to a new file and import it) and create hierarchies.
```css
.navbar-wrapper {
    position:absolute;

    .container {
        paddin-left:0;
    }
}
.navbar-content {
    width: 320px; /* /!\ this is not reactive friendly! */
    &:before, &:after {
        content: "";
    }
}
```