Add sass

.gitignore

@@ -2,3 +2,4 @@
 .idea
 .DS_Store
 node_modules
+yarn-error.log

next.config.js

@@ -0,0 +1,3 @@
+const withSass = require('@zeit/next-sass');
+
+module.exports = withSass({});

package.json

@@ -9,7 +9,9 @@
     "start": "next start"
   },
   "dependencies": {
+    "@zeit/next-sass": "^1.0.1",
     "next": "^9.0.4",
+    "node-sass": "^4.12.0",
     "react": "^16.9.0",
     "react-dom": "^16.9.0"
   }

postcss.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+  plugins: {
+    'postcss-css-variables': {},
+  },
+};