Seismic design of structures is a whole division of structural engineering and probably the most important aspect. Dynamic forces caused by earthquakes are studied and designs ar done accordingly. For example, the location and geometry of shear walls, which would resist earthquakes are important. The reinforcing steel that you use at high moment locations such as where beams and columns join is important. Seismic designs of foundations make probably the biggest impact as the earthquake force is first transferred to the building from foundation. Some foundations have isolators that would break or flex during an earthquake for instance in order to absorb the energy. The keyword here is to absorb energy caused by earthquake that enters into the building. This subject is too large to be summarized like this but I tried to give you an idea, it is really a huge subject of engineering where many lifetimes of study will not be enough.