Waterproof phones and watches exist. So, the tech exists. For a laptop, the main obstacle is due to the hinge / interface between the base holding the keyboard

Waterproof phones and watches exist. So, the tech exists. For a laptop, the main obstacle is due to the hinge / interface between the base holding the keyboard and the screen if one were to go with the traditional design of a laptop. As others pointed out, rugged laptops come close.