Unable to set background image on page

Ionic Framework
1

I’ve been unable to set a background image in Ionic 4. I’ve tried

     ion-content {
       --background: #fff url("../../../assets/img/login-image.jpg") no-repeat center center / cover;
     }

and
ion-content {
background-image: url("…/…/…/assets/img/login-image.jpg");
-webkit-background-image: url("…/…/…/assets/img/login-image.jpg");
background-repeat: no-repeat;
background-size: cover;
}

I’m certain the relative paths are correct because if I change them I get a compile error.

page-details {
     ion-content {
       --background: #fff url("../../../assets/img/login-image.jpg") no-repeat center center / cover;
      // background-image: url("../../../assets/img/login-image.jpg");
      // -webkit-background-image: url("../../../assets/img/login-image.jpg");
      // background-repeat: no-repeat;
      // background-size: cover;
     }
form {
  margin-bottom: 32px;
  button {
    margin-top: 20px !important;
  }
}

p {
  font-size: 0.8em;
  color: #d2d2d2;
}

ion-label {
  margin-left: 5px;
}

ion-input {
  padding: 5px;
}

.invalid {
  border-bottom: 1px solid #ff6153;
}

.error-message {
  min-height: 2.2rem;
  ion-label {
    margin: 2px 0;
  }
}
}
`type or paste code here`