docs: update mode styles in theme documentation (#177)

Co-authored-by: sxyazi <[email protected]>

docs/configuration/theme.md

@@ -97,18 +97,29 @@ Highlighting: The built-in syntax highlighting feature
 
   Code preview highlighting themes, which are paths to `.tmTheme` files. You can find them on GitHub [using "tmTheme" as a keyword](https://github.com/search?q=tmTheme&type=repositories)
 
+## [mode] {#mode}
+
+Normal mode
+
+- normal_main (Style): Normal mode main style.
+- normal_alt (Style): Normal mode alternative style.
+
+Select mode
+
+- select_main (Style): Select mode main style.
+- select_alt (Style): Select mode alternative style.
+
+Unset mode
+
+- unset_main (Style): Unset mode main style.
+- unset_alt (Style): Unset mode alternative style.
+
 ## [status] {#status}
 
 - separator_open (String): Opening separator symbol. e.g. `"["`.
 - separator_close (String): Closing separator symbol. e.g. `"]"`.
 - separator_style (Style): Separator style.
 
-Mode
-
-- mode_normal (Style): Normal mode style.
-- mode_select (Style): Select mode style.
-- mode_unset (Style): Unset mode style.
-
 Progress
 
 - progress_label (Style): Progress label style.