Peng Wang

Results 1 issues of Peng Wang

### Expected behavior load main.css using preload `` instead of `` this will also get rid of the lighthouse waring: ![a8197e00-9c15-11e9-9380-5b82f2df6afc](https://user-images.githubusercontent.com/3408470/63297399-24c7f080-c286-11e9-8fde-f9f0bec59667.png)

enhancement