3. In the acute triangle $\triangle A B C$, it is known that $\angle A=60^{\circ}$, $B D$ and $C E$ are the altitudes from $B$ and $C$ to the sides $A C$ and $A B$ of $\triangle A B C$, respectively. If $S_{\triangle A B C}=1$, then the area of quadrilateral $B C D E$ is $\qquad$
3. $\frac{3}{4}$