Changing registration button shape

Hi,

The size and dimension of the orange registration button on the form looks a bit small and untidy.
See screenshot: https://postimg.cc/XrTcvYBc
How can I increase the the length (width) so that all the text can be on one line?
How can the height of the button be changed?

Kind regards,

Yunis

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