The tinro is highly declarative, very tiny (~4.5 Kb (1.9 Kb gzipped)), dependency free router for Svelte's web applications.
You may also be interested in ...
Responsively
Master the Art of Crafting Responsive Web Apps. A must-have DevTool for all web developers that will make your job easier. It's free and open source too!
PaperCSS
The less formal CSS framework.
Greensock
GreenSock is a JavaScript plateform which makes it easy to animate HTML elements. As long as you have an understanding of HTML and CSS, along with a basic knowledge of JavaScript, you’ll be equipped with everything you need to build your animation with Greensock.