Recommended tools for Theme Development with SASS

My question is - what are other people's processes in most efficiently developing WordPress themes that utilize SASS and what tools are you using? I also develop from multiple locations/machines (both Windows/OSX) so I would like to have my dev environment stored centrally.

A bit about my requirements - I work for a web development business and would like to start developing my own WP themes with SASS but I can't find a clear solution on what tools I should be using.

Normally my development environments reside on a subdomain I create off my website which I password protect/hide from Google etc. This works well because not only does it free up my PC's resources (compared to if I was building it locally) but I can access the dev environment from any machine.

That being the case (wanting my dev environments to not be stored locally), I am more than happy to use the code editor tools offered in cPanel to modify the files directly on the site however I am wanting to start using SASS which requires compiling, which from what I assume needs to be done locally.

Thanks!