Screenshot attached, taken from desktop for convenience, but the same thing happens on my phone.*
Having the login form requiring scrolling to access all content is not sensible. The problem is (once again) that daft 5 em max-height that is set on the parent element. Killing that, and substituting a saner value (like 50% or even 70%) would be much better.
Also, for some reason the login form is still using two definition lists for something where dl's are not really suitable. Inputs should have functioning labels.
And having three separate paragraph tags to hold one button, and two anchors below it, is a tad bonkers too. You could do this form with damned near half the markup and better a11y, and CSS would still be dead simple.
ETA: Oh and the top left and top right border radius on the content div looks silly without the side padding on the parent. For smaller screens that should be set to border-radius: 0;
*(Motorola 5G Plus - Display 1080 × 2520 - CSS pixels 414 x 966 - DPR 2.61).