A step in a path · back on the left
Note: a sub page is a step in a path, so it carries a back arrow on the left of the top row. A close cross on the right is only for screens opened over something else. No accent colour in the form — crimson appears on the destructive line only.
1 · Edit profile: one rounded card, label and value stacked, thin lines between. No input boxes.
2 · Sign in: filled box, no label above. The grey placeholder is the label. Text is 16px so the phone doesn't zoom in.
Threads standard (approx., from the iOS app)
Field label: 15px, semibold, white
Typed value: 15px regular (16px in sign-in boxes)
Placeholder: same size, grey
Sign-in box: 56px tall, 12px corners, filled grey
Profile card: 16px corners, 12px row padding, thin lines
Error: 13px red text under the field; nothing marks required fields
Ours now: label 15px semibold white above, value 15px regular in a box, hint/error 13px under — the Threads standard.