Sass Courses
Kevin Powell via YouTube Sass Features That Make It Better Than Vanilla CSS
Kevin Powell via YouTube Dynamic CSS with Custom Properties (aka CSS Variables)
Frontend Masters Advanced CSS Layouts
Frontend Masters Sass Fundamentals
Frontend Masters Accessible Cross-Browser CSS Form Styling
egghead.io Convert SCSS (Sass) to CSS-in-JS
egghead.io Make Webpack Easy with Poi
egghead.io Learn the Fundamentals of CSS and Sass to Create Modern and Responsive Layouts
egghead.io Hands-On Introduction: React
LinkedIn Learning