#container_login {
    margin-top: -40px; 
    z-index: 1; 
    position: relative; 
    width: 50%;
}


@media (max-width: 1000px) {
  #container_login {
    margin-top: -40px; 
    z-index: 1; 
    position: relative; 
    width: 100%;
  }
}