The change is that an input element is now wrapped in a div. So your custom styling is now applied to the div instead of the input, as it was before.
I would advice solving this by changing the styling using classed instead of directly on the element.
You could for example add a footer class to the container and add the following example code to the theme:
.footer input {
[YOUR INLINE STYLE CAN BE PASTED HERE]
}
As an alternative you can change the read-only style to Text