body{
    color: #b8fcb8e5;
}

@media (min-width: 320px) {
    .fondoprincipal{
        background-image: url(img/tapa.png);    
        background-color: transparent;
        background-position: center top;
        background-attachment: fixed;
        background-size: contain;
    }    
    .login-form{
        width: 70% !important;
    }
}
@media (min-width: 480px) {
    .fondoprincipal{
        background-image: url(img/tapa.png);    
        background-color: transparent;
        background-repeat: no-repeat;
        background-position: center top;
        background-attachment: fixed;
        background-size: contain;
        width: 80%;
    }    
}
@media (min-width: 820px) {
    .fondoprincipal{
        background-image: url(img/tapa.png);    
        background-color: transparent;
        background-repeat: no-repeat;
        background-position: center top;
        background-attachment: fixed;
        background-size: contain;
        width: 80%;
    }    
}
@media (min-width: 720px) {
    .fondoprincipal{
        background-image: url(img/tapa.png);    
        background-color: transparent;
        background-repeat: no-repeat;
        background-position: center top;
        background-attachment: fixed;
        background-size: contain;
        width: 50%;
    }
}
@media (min-width: 768px) {
    .fondoprincipal{
        background-image: url(img/tapa.png);    
        background-color: transparent;
        background-repeat: no-repeat;
        background-position: center top;
        background-attachment: fixed;
        background-size: contain;
        width: 50%;
    }
}
@media (min-width: 1200px) {
    .fondoprincipal{
        background-image: url(img/tapa.png);    
        background-color: transparent;
        background-repeat: no-repeat;
        background-position: center top;
        background-attachment: fixed;
        background-size: contain;
        width: 30%;
    }
}