body {
  background: url("../images/bg.jpg")no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}
#DIAWrapperLogin, #DIAWrapperMain {
  margin: 20px auto;
  width: 700px;
}
#DIAImageHeader {
  max-width: 100%;
}
@media (max-width: 767px) { 
  #DIAWrapperLogin, #DIAWrapperMain {
    width: 95%;
  }
}
@media (max-width: 480px) {
  #DIAWrapperLogin, #DIAWrapperMain {
    width: 95%;
  }
}