I would think the speed of the light leaving the headlights would be increased by the speed of the car, and would go out in front of you. I'm not sure what you would be able to see in the headlights at that speed, not even sure what the light energy would do when it tries to reflect off an object at that speed. You should be able to see light in any other direction, except directly behind you. But it would probably be distorted images, due to the bending of the light waves as you travel through them. Like sound, the frequency would change as you move, like a train when it passes. It'd be interesting to find out. Maybe it would be like a painting, smeared. The old belief that the speed of light is the maximum speed attainable was proven false years ago. Just as the speed of sound was once thought to be the barrier, light speed can be passed. Think of an enormous wheel turning slowly at the center. The outside edge, if the wheel is big enough, would be able to move faster than the speed of light. It may be there are galaxies turning at a speed and size to prove this, but how to see and measure it?