Surface Integrals, Stokes & Divergence · Medium problem

Let $\mathbf F$ be any smooth vector field on all of space whose curl is the constant vector $\nabla\times\mathbf F=(2,-1,3)$ everywhere. Let $S$ be the outward-oriented boundary of ANY solid region with no holes (a closed surface). Find $\displaystyle\iint_S(\nabla\times\mathbf F)\cdot d\mathbf S$.