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This is the default hosted page appearance. This is mainly for users who would like to just get started with the basic checkout page style and do not have either the time or need additional development assistance to customize it.
Here you can:
a) Upload your favicon and company logo. Size limit is 256 KB each.
b) Add a header text in case you are not going to upload a logo.
Header background and font color can be customized as well.
Suggested look for your hosted pages would be using themes. Find out more about themes here.