diff --git a/book/src/themes.md b/book/src/themes.md
index 4c0eda228..57a8d5d1f 100644
--- a/book/src/themes.md
+++ b/book/src/themes.md
@@ -228,6 +228,7 @@ These scopes are used for theming the editor interface.
 | `ui.text.info`            | The key: command text in `ui.popup.info` boxes |
 | `ui.virtual.ruler`        | Ruler columns (see the [`editor.rulers` config][rulers-config])|
 | `ui.virtual.whitespace`   | Visible white-space characters                 |
+| `ui.virtual.indent-guide` | Vertical indent width guides                   |
 | `ui.menu`                 | Code and command completion menus              |
 | `ui.menu.selected`        | Selected autocomplete item                     |
 | `ui.selection`            | For selections in the editing area             |
diff --git a/runtime/themes/onedark.toml b/runtime/themes/onedark.toml
index 280f6914d..d0cbb9494 100644
--- a/runtime/themes/onedark.toml
+++ b/runtime/themes/onedark.toml
@@ -47,6 +47,8 @@ diagnostic = { modifiers = ["underlined"] }
 "error" = { fg = "red", modifiers = ["bold"] }
 
 "ui.background" = { bg = "black" }
+"ui.virtual" = { fg = "faint-gray" }
+"ui.virtual.indent-guide" = { fg = "faint-gray" }
 "ui.virtual.whitespace" = { fg = "light-gray" }
 "ui.virtual.ruler" = { bg = "gray" }
 
@@ -85,5 +87,6 @@ white = "#ABB2BF"
 black = "#282C34"
 light-black = "#2C323C"
 gray = "#3E4452"
+faint-gray = "#3B4048"
 light-gray = "#5C6370"
 linenr = "#4B5263"
diff --git a/theme.toml b/theme.toml
index 7a518b2fe..8e550f922 100644
--- a/theme.toml
+++ b/theme.toml
@@ -56,6 +56,8 @@ label = "honey"
 "ui.text.focus" = { fg = "white" }
 "ui.virtual" = { fg = "comet" }
 
+"ui.virtual.indent-guide" = { fg = "comet" }
+
 "ui.selection" = { bg = "#540099" }
 "ui.selection.primary" = { bg = "#540099" }
 # TODO: namespace ui.cursor as ui.selection.cursor?