The landing page looks awesome. Congratulations on the nice design.
I suspect you are being hammered with requests now. Because in both Brave and Chrome, there is about a .5 second delay until the new tab page appears. Until then, there is just a black screen.
For the first time, it can take a while because it needs to cache the data url of an image for offline usage. After that, it should load faster. If you have any performance issues, please open a GitHub issue