body.login{
  background-image: url(image/login_fir.png);
  background-repeat: no-repeat;
  background-position: center 450px ;
  padding: 0;
  height: 750px;
}
#login {
width: 320px;
padding: 2% 0 0;
margin: auto;
}
.login h1 a {
    background: url(image/logo_e-yamagata.png) no-repeat 50px center;
    background-color: #fff;
    width: 320px;
    height: 60px; 
    margin-bottom: 5px;
    box-shadow: 0 1px 3px rgba(0,0,0,.13);
}
#login p#nav, #login p#backtoblog {
   display: none;
   }
   
@media screen and (max-width: 767px) {
body.login{
background-size: contain;
}

}