Vanity-Free Bottle / daily use

I redesign the hand sanitizer bottle in order to reduce the waste of liquid soap. It has been a common phenomenon that hand sanitizer or shampoo bottles are discarded with some remaining liquid at the bottom,for the remaining liquid at the bottom can't be extracted easily. To solve this problem, I redesigned the shape of bottle , especially made the bottom of the bottle to be centra-concave. So the remaining liquid can be gained in the centre, and the liquid in the bottle can be more fully used.