Sass 사용법
Sass (Syntactically awesome style sheets) 
CSS (stylesheet language) 
"SCSS" (Sassy CSS) 
- CSS 와 유사한 문법의 Sass 
//=============== 
* node package 설치 
style-loader(css를 html style에 출력) 
css-loader(js안의 css해석, 의존성 해결) 
sass-loader(sass -> css) 
node-sass(sass -> css) 
babel : 자바스크립트 ES6 -> ES5 로 변환 
npm install style-loader css-loader sass-loader node-sass --save-dev 
//================ 
- webpack.config.js 설정 
module.exports = { 
module: { 
rules: [ 
            { 
                test:/\.(s*)css$/, 
                use: [ 
                    'style-loader', 
                    'css-loader', 
                    'sass-loader' 
                ] 
            } 
        ] 
} 
  } 
//========================= 
//참고 
https://heropy.blog/2018/01/31/sass/ 
https://medium.com/a-beginners-guide-for-webpack-2/using-sass-9f52e447c5ae 
https://jsstudygroup.github.io/jsStudyBlog/posts/webapck02/ 
https://heropy.blog/2017/10/18/webpack_1_start_ejs_sass/ 
https://medium.com/@shlee1353/%EC%9B%B9%ED%8C%A9-%EC%9E%85%EB%AC%B8-%EA%B0%80%EC%9D%B4%EB%93%9C%ED%8E%B8-html-css-%EC%82%AC%EC%9A%A9%EA%B8%B0-75d9fb6062e6