Something went terrible wrong!
First, try reloading the site with CTRL+F5 (CMD+F5 for MAC-people).
Then, check out the console with F12, if you got any errors. Also, take a screenshots because those always helps!
If that does not solve the issue, start a thread on Reddit.com/r/CityInc/
explaining how you got this error, along with any Console Errors and screenshots.