Quarks are elementary particles and are considered to be point-like particles, meaning they are treated as having zero size or taking up no space in traditional particle physics theories. According to the current understanding of quarks within the framework of the Standard Model of particle physics, they are considered to be fundamental particles without any internal structure.
However, it is important to note that the concept of "taking up space" can be somewhat ambiguous when dealing with quantum mechanics and subatomic particles. Quantum field theories describe particles as excitations of underlying fields, and these excitations can be spread out or localized to different degrees depending on various factors.
So, while quarks are usually described as point-like particles with no size, the understanding of their precise nature and behavior is an ongoing topic of research in theoretical physics. Experimental evidence and future discoveries may provide further insights into the properties of quarks and their spatial extent, if any.