CSS3, SASS, SCSS, COMPASS, LESS, BOURBON

CSS
li {
  font-family: serif;
  font-weight: bold;
  font-size: 1.2em;
}

SCSS
li {
  font: {
    family: serif;
    weight: bold;
    size: 1.2em;
  }
}

SASS
li
  font:
    family: serif
    weight: bold
    size: 1.2em

COMPASS, LESS, BOURBON sono i motori che creano CSS