====== SASS ======
I prefer this over LESS simply because it has a bigger ecosystem. (also Googling it doesn't return info about the Linux command)

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===== Installation =====
<code bash>
npm install --save-dev sass
</code>

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===== Compilation =====
Tip: in your sass directory make everything a submodule (by naming the file with an _filename.scss) then create an app.scss which imports all the other submodules. Then you will get a single compressed app.css 
<code bash>
./node_modules/sass/sass.js --watch sass:static/css --style compressed
</code>
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