  We present a simple version of hadron-quark hybrid (HQH) model in the
$\mu_B$--$T$ plain, where $T$ is temperature and $\mu_{B}$ is the baryon-number
chemical potential. The model is composed of the independent-quark model for
quark-gluon states and an improved version of excluded-volume hadron resonance
gas (EV-HRG) model for hadronic states. In the improved version of EV-HRG, the
pressure has charge conjugation and is obtained by a simple analytic form. The
switching function from hadron states to quark-gluon states in the present
model has no chemical potential dependence. The simple HQH model is successful
in reproducing LQCD results on the transition region of chiral crossover and
the EoS in $\mu_{B} \leq 400$ MeV. We then predict the chiral-crossover region
in $400 \leq \mu_{B} \leq 800$ MeV. We also predict a transition line derived
from isentropic trajectories in $0 \leq \mu_{B} \leq 800$ MeV and find that the
effect of strangeness neutrality is small there.
