Don't doubt our commitment to Sparkle Motion.
This is a base theme intended for sub-themes to be based on. Subliminal is a sub-theme ready for you to customize, see its README for more info.
npm install to setup SASS stack for theming.
gulp css to compile SASS.
gulp watch to compile SASS as you edit.
gulp compile to comb, compile, and lint your SASS to clean it up to our standards.
Alternatively you can also just gulp comb (to actually reformat .scss files to a common spacing, etc) and gulp lint (to check for linting errors, warnings are OK but there to make sure you did what you did on purpose).