Is there any way to set background color of lines in GoLand (JetBrains IDE)?

Sticky selection can do that trick.

there is the brief intro about it:

you can mark a selection to be permanently highlighted, even when your caret moves away. Inspired by "Style token" of Notepad++. You can define an arbitrary number of Paint Groups. Selecting the appropriate editor action (keystroke or context menu), the all occurrences of currently selected text will be added to the Paint Group and will be permanently highlighted (until you clear the selection with an other editor action). So you can have different text fragments to be selected with the same Paint Group. The Paint Groups are kept when IntelliJ is closed.

You can set different colours for each Paint Group
You can set a marker to be visible on the right side of the editor
You can add multiple selections to the same group
You can convert a Paint Group to multi caret selection (and thus edit, copy, delete, etc. it)
For convenience you can undo the last addition (until the document is edited)
You can cycle through each element in a given Paint Group or in all Paint Groups
Keymap actions are added dynamically for paint, clear and convert as you add more Paint Group

There are a few ways to mark some lines and add them to the "Reading" list:

• Bookmarks. It is built-in functionality in IntelliJ-based IDEs. You can go to the line with Authenticator interface declaration and select Edit | Bookmarks | Toggle Bookmark in the main menu. All bookmarks are available in View | Tool Windows | Bookmarks.
• 3rd-party plugins. I'm aware of MultiHighlight plugin that supports selection of the piece of code.