You are in a ship traveling at 99.999999% the speed of light.
the ship is 100 feet long and you are at the back.
you decide to jump up and run to the front of the ship.
Technically you just ran past the speed of light.
Same principle except the bubble is the ship and the ship is you.
Confusing I know but just think about it.
Another more common scenario.
You are in your car traveling at 60 mph.
you throw a ball up in the air in your car.
How fast is the ball traveling?
Now your kid in the back has the ball and throws it to the front.
How fast is it going now?