1. Let $x, y, z$ satisfy:
$$
\left\{\begin{array}{l}
\log _{2}\left(x y z-3+\log _{5} x\right)=5, \\
\log _{3}\left(x y z-3+\log _{5} y\right)=4, \\
\log _{4}\left(x y z-3+\log _{5} z\right)=4 .
\end{array}\right.
$$

Then $\log _{5} x y z=$ $\qquad$