Light mode (#38)

package.json

@@ -19,6 +19,7 @@
     "autoprefixer": "^10.4.14",
     "codemirror": "^6.0.1",
     "cssnano": "^5.1.15",
+    "github-markdown-css": "^5.2.0",
     "highlight.js": "^11.7.0",
     "markdown-it": "^13.0.1",
     "moment": "^2.29.3",
@@ -27,6 +28,7 @@
     "postcss-cssnext": "^3.1.1",
     "postcss-import": "^15.1.0",
     "postcss-loader": "^7.1.0",
+    "sass": "^1.62.1",
     "sugarss": "^4.0.1",
     "tailwindcss": "^3.2.7",
     "vite": "^4.2.1"