This site is made using SvelteKit. Most of the styling is hand-rolled CSS, with CCS variables for colour and sizing.
Additionally, it also uses a modified version of Sakura, as a base for all the styling. Sakura is a class-less CSS "framework" that makes things look very pretty, I really love it, you should check it out! :)
Can't forget about the ♥ used to make the site, that's an integral part!