Does hugo-prose support multiple level header menu？

[gaospecial]

I create a folder about and placed two markdown files: file1.md and file2.md in it. So is it possible to add a menu about with two subitem file1 and file2?

Where should I check to understand the underlying mechanism of menu integration in this theme?

[yihui]

It's possible but the CSS might be a little complicated. To define a menu item with children, the child items need to declare their parent. The documentation is here: https://gohugo.io/content-management/menus/ I don't have much experience here, so you may need to find the CSS by yourself.