As you can see, when it switches from a standard PC monitor to a phone, the space in between the rectangles widens too much and the white frames grows too big.
Here is a file you can edit and check the hierarchy of the gui and stuff: GuiFix.rbxm (6.3 KB)
I know that this is off topic but dont you want to censore your username? Why do you need the white frame to always be the same size? Which white frame do you mean? The one at the top ot those around the buttons?