Trouble getting Sass working in Sinatra project

I am currently in the early stages of setting up a Ruby project using Sinatra and am having some trouble getting Sass up-and-running. I’ve read through documentation on a number of ways to do this, and have even taken a look at a few example projects, but each seems to have their own unique project directory structure and Sass configurations (some are very simple, whilst others are can get quite lengthy) adding to the confusion I have around what is actually necessary. Whist this isn’t my first time working with Ruby, this is the first time I’ve used Sass, and having not worked on a project like this in over a year, I am definitely feeling the effects of being out of practice for so long :)

My current set up includes the Sass and Compass gems, with configuration roughly based on the Sinatra integration documentation on the Compass Github wiki: https://github.com/Compass/compass/wiki/sinatra-integration

I have my Sass directory nested at the same level as the CSS directory (e.g. “~/Public/Sass" and “~/Public/css”), which I have been attempting to link in “views/layout.erb” like so:

<link rel="stylesheet" type="text/css" media="all" href="/public/css/style.css" />

Thus far, every time I start up the server and take a look at the console I get a “Failed to load resource” error. Not certain if this is because of a simple syntax error or something larger, but I welcome any solutions to get Sass running and any general advice on cleaning up dependencies (don’t know if the Compass gem is necessary if I’m just using Sass / no Haml), config files, etc.

GitHub link to project: https://github.com/rileytippetts/postbag/tree/feature/user-onboard