<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteBase /

  # Keep real files and directories untouched.
  RewriteCond %{REQUEST_FILENAME} -f [OR]
  RewriteCond %{REQUEST_FILENAME} -d
  RewriteRule ^ - [L]

  # SPA fallback.
  RewriteRule . /index.html [L]
</IfModule>

<IfModule mod_mime.c>
  AddType application/javascript .js .mjs
</IfModule>
