style improvements to head-logo
style improvements to head-logo

size and proportions of the logo image is not managed more easily by
simply adjusting the 'background-size' percentage and the
'background-position'. this undos the needs for padding/margin. it's
easier to adjust 1 property rather than 2

circleci/frontend,RayRutjes/frontend,prathamesh-sonpatki/frontend,circleci/frontend,prathamesh-sonpatki/frontend,circleci/frontend,RayRutjes/frontend