MathNet 2017-part-02 — 176 problems (EN–VI) Question 19

Points $M$ and $N$ lie on the sides $\overline{BC}$ and $\overline{CD}$ (respectively) of the square $ABCD$ so that $\angle BMA = \angle NMC = 60^\circ$. Determine $\angle MAN$. (Ukraine 2013)