[Barrier-free design of this site]

This site is established based on the barrier-free design principle, and the content of the site is divided into three sections：

1. Top function section; 2. Central content section; 3. Lower menu and link section.

The access keys of this site are set as follows:

Alt + U: The top navigation link section, which contains the main links of this site.

Alt + C: The central content block, which contains the main content of the page.

Alt + Z: Site information at the end of the page.

Alt + R: Right layout block.

If you are using Firefox, the keyboard shortcut will be Shift+Alt+ (shortcut alphabet), e.g. Shift+Alt+C is the key to the center of the website.