diff --git a/lib/bds/tui.ex b/lib/bds/tui.ex
index 0dd2f4e..4cf41de 100644
--- a/lib/bds/tui.ex
+++ b/lib/bds/tui.ex
@@ -1474,7 +1474,10 @@ defmodule BDS.TUI do
        language: :markdown_macros,
        block: %Block{title: body_title, borders: [:all]},
        cursor_style: if(focused?, do: %Style{bg: :cyan}, else: %Style{}),
-       line_highlight_style: if(focused?, do: %Style{bg: :dark_gray}, else: %Style{})
+       # base16-ocean's lighter-background grey — a fixed RGB so the
+       # current-line marker stays dark (and readable) in any terminal
+       # palette, unlike the named :dark_gray colour.
+       line_highlight_style: if(focused?, do: %Style{bg: {:rgb, 52, 61, 70}}, else: %Style{})
      }, body_rect}
   end
 
diff --git a/test/bds/tui_test.exs b/test/bds/tui_test.exs
index 92cd5b4..a746eda 100644
--- a/test/bds/tui_test.exs
+++ b/test/bds/tui_test.exs
@@ -154,8 +154,10 @@ defmodule BDS.TUITest do
     assert ExRatatui.textarea_cursor(state.editor.textarea) == {0, 5}
 
     cells = screen_cells(state)
-    assert cell_at_text(cells, "first").bg == :dark_gray
-    refute cell_at_text(cells, "second").bg == :dark_gray
+    # A fixed dark grey — readable against the light syntax colours in
+    # any terminal palette (the named :dark_gray is palette-dependent).
+    assert cell_at_text(cells, "first").bg == {:rgb, 52, 61, 70}
+    refute cell_at_text(cells, "second").bg == {:rgb, 52, 61, 70}
   end
 
   test "ctrl+s persists textarea edits", %{post: post} do