It is possible to edit the look of the customer accessed pages by adding custom CSS code under Menu -> Settings -> Customer Pages CSS Styling. There are a lot of possibilities but here are a few examples you can add:
Hide the logo in the navigation bar
#logoSmall, #logoLarge { display: none; }
Hide the navigation bar
#topNav { display: none; }
Hide the footer
#bottomNav { display: none; }
Change the default font to Times New Roman
body { font-family: "Times New Roman", Times, serif; }
Change the color of the white default buttons
.btn-default { color: white; background-color: black; }