The engine will resolve relative paths in the best of it abilities even when you want to build your site for production.
Relative path to assets are resolve even when you link them from partial files. All paths end up being resolved in relation to the page template file the partial was included at.
<img src="../assets/logo.png" alt="log">
Relative path of assets in CSS are also resolved even if you import different files. They are all resolved to be inside the pages directory in relation to the page the css file is linked to.
import logo from "../assets/logo.png";