Can’t connect Vuetify to project

I followed offical documentation to install vuetify, but I’ve got trouble with that. When I am trying add vuetify to my project, I always get two types of errors: First type: P.S .app-main is my style class. Without vuetify it works fine. Second type: I am not sure what the affects are on changing errors, but they are changing when I change code in main.js file package.json My Webpack.config.js Answer Solving by adding this property to Webpack: Main.js