Tumblr Blog Pages
Tumblr Custom Pages
Apart from the main blog pages where your Tumblr posts are displayed, you can also add custom pages to your blog. These custom pages are accessible from links on your blog page and can have either a standard or custom layout. If you select the standard layout, your custom pages have the same appearance as your currently active blog theme. If you opt for a custom layout, you can use your own code to specify the way that the page looks. By using a custom layout for each of your pages, you can display a different background image or color on every page.
Tumblr External Pages
Apart from custom pages that are linked to your Tumblr blog, you can also link external pages. Tumblr adds a link to your blog that redirects to the external website page when clicked. As these external pages are not part of Tumblr, you cannot edit or change anything about the pages from the Tumblr editor. If you are the owner of the pages to which you are linking, you can edit the HTML source code using an external editor to change the background for each page.
Tumblr Dashboard Pages
Your Tumblr dashboard page is a single page where you can view your own blog posts, create new posts and view posts by other Tumblr users that you are following. Like your blog, your dashboard can be set to either scroll endlessly or display a certain amount of posts per page. However, your dashboard does not use the same theme as your blog, and there is no native option for customizing the background. You can use third party browser extensions such as Stylish and Nice Tumblr (links in Resources) to add custom background images and colors.