CSS ------------------ ### Font sizes and units It's `rem` all the way. The base font size is defined as `px`-based variable and set once the `html` root element. All other font sizes and spacing values are set as `rem` units, being nicely relative to the root font size. ```css html { font-size: 18px; } p { font-size: 1rem; } ``` ### Vendor Prefixes Just write the official, unprefixed syntax for all CSS 3 features, no need to write the vendor prefixed versions. [Autoprefixer](https://github.com/postcss/autoprefixer) handles that for you automatically based on the browser versions defined in the task and data from [Can I Use](http://caniuse.com/). SVG sprite ------------------ All icons and most assets are SVGs. A gulp task grabs all svg files from the `img/` folder and puts them as `` into one SVG sprite file. Reference those icons with the SVG `` element and their ID in the HTML where you want them to be: ```html ```