For all of you who are having issues with the resolution in PC, the game is created for Mobile but I've ported it to desktop. The windowed version exist because some desktop with certain specs will have the game to zoomed and therefore you can adjust the size of the window... Sorry but I am still learning Unity Canvas system which I find a bit weird compared to responsive web design... I do have plans to fix this in the future and support full screen, but for the moment that's the only quick fix I have!
Although I'm an engineer, this is my first game so I'm still learning a lot of things! If there's any issue please kindly go to my discord and post a screenshot so I can try to fix it when I have time. Please let me know the detail of your device too (your version, desktop resolution or if you are on android your device type)