I think it is looking smooth Because of relative motion you can also use it. Road move faster and car move slower but in your case how will you let your car back to down you don't have break system once you Add motion to car it will go on to the top and then hide there.
ben hur sia I know I am saying when we move car in the "full speed" car moves smoothly but in my car moves hardly
Divya Mohan how can I add the motion is it js or css
Css is ok if you want. But if your js is good it will be best.