An ideal parallel-plate capacitor with plate area \(A\) and plate separation \(d\) has capacitance \(C_0\) in a vacuum. The space between the plates is completely filled with two rectangular dielectric slabs placed side-by-side, both spanning the entire separation distance \(d\). Slab 1 has dielectric constant \(\kappa_1\) and covers an area of \(\frac{1}{3}A\), while Slab 2 has dielectric constant \(\kappa_2\) and covers the remaining area of \(\frac{2}{3}A\). What is the total equivalent capacitance of this capacitor in terms of \(C_0\), \(\kappa_1\), and \(\kappa_2\)?