Redefine the maketitle function in the theme with a background color and center the title of slides.
from beampy import *
doc = document(theme="HipsterChic", quiet=True)
with slide():
maketitle('Beampy theme ``HypsterChic"',
author='Single Author',
subtitle='A very very very very very long subtitle on the right')
display_matplotlib(gcs())
with slide('Slide title are centered'):
pass
display_matplotlib(gcs())