Fix WordPress Header/Footer Layout

A recent WordPress update broke the site-wide header and footer built with my header-footer plugin. Both elements still render, yet everything is out of place: the menu, logo and navigation links have shifted, spacing and alignment are off, and text, colours and buttons no longer match the theme... (Budget: £20 - £250 GBP, Jobs: CSS, Frontend Development, HTML, JavaScript, PHP, Web Design, Web Development, WordPress)