It may seem hard, but you'll find it easy.
Pick up the background
Take down the backstage of Typecho directly from Ctrl-S
Then create a new Admin folder in your Themes folder, and then create a new index .php paste this into the beginning
Then go out and create a new head.php paste the head code just copied, and then change the original path to call the theme address, the public library some do not call the local, and finally change the title to call the current page