iPhone not properly showing image area on site. Why?

[Don]

Hello

I didn’t test it but it looks like to me it is caused the background-attachment: fixed;

CSS background-attachment | Can I use... Support tables for HTML5, CSS3, etc

The code you shared above there is:

.title-container {
  background: no-repeat center/cover fixed;
}

Which means:

.title-container {
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
  background-attachment: fixed; // this cause the issue
}

Is the background-attachment: fixed; necessary in this case?

I mean I think it probably makes a kind of parallax effect. But this is not the best solution for that…as this is not too supported and maybe not necessary for your use case.