Probably, like other levels, my solution has been broken by game updates. The same principle should still solve it, though.

How did you manage to make the upper bridge? In my case the first two cars can pass through the portals, but the remaining ones crash in the air

Great! Have fun with the rest of the game!

level*

I used your bridge as an inspiration and beat lever 30 after trial and errer, The final part to get to the exit was your bridge. The early designs of my bridge was r/therewasanattempt worthy, though