diff --git a/lisp/vc/ediff-init.el b/lisp/vc/ediff-init.el
index 6e658163b9..3f33e6aae2 100644
--- a/lisp/vc/ediff-init.el
+++ b/lisp/vc/ediff-init.el
@@ -980,8 +980,10 @@ stipple-pixmap
 (defface ediff-even-diff-A
   `((((type pc))
      (:foreground "green3" :background "light grey" :extend t))
-    (((class color) (min-colors 88))
-     (:background "light grey" :extend t))
+    (((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "light grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dark grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "Black" :background "light grey" :extend t))
     (((class color))
@@ -999,8 +1001,10 @@ ediff-even-diff-face-A
 this variable represents.")
 
 (defface ediff-even-diff-B
-  `((((class color) (min-colors 88))
-     (:background "Grey" :extend t))
+  `((((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "Grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dim grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "White" :background "Grey" :extend t))
     (((class color))
@@ -1019,8 +1023,10 @@ ediff-even-diff-face-B
 (defface ediff-even-diff-C
   `((((type pc))
      (:foreground "yellow3" :background "light grey" :extend t))
-    (((class color) (min-colors 88))
-     (:background "light grey" :extend t))
+    (((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "light grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dark grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "Black" :background "light grey" :extend t))
     (((class color))
@@ -1040,8 +1046,10 @@ ediff-even-diff-face-C
 (defface ediff-even-diff-Ancestor
   `((((type pc))
      (:foreground "cyan3" :background "light grey" :extend t))
-    (((class color) (min-colors 88))
-     (:background "Grey" :extend t))
+    (((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "Grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dim grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "White" :background "Grey" :extend t))
     (((class color))
@@ -1068,8 +1076,10 @@ ediff-even-diff-face-alist
 (defface ediff-odd-diff-A
   '((((type pc))
      (:foreground "green3" :background "gray40" :extend t))
-    (((class color) (min-colors 88))
-     (:background "Grey" :extend t))
+    (((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "Grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dim grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "White" :background "Grey" :extend t))
     (((class color))
@@ -1088,8 +1098,10 @@ ediff-odd-diff-face-A
 (defface ediff-odd-diff-B
   '((((type pc))
      (:foreground "White" :background "gray40" :extend t))
-    (((class color) (min-colors 88))
-     (:background "light grey" :extend t))
+    (((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "light grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dark grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "Black" :background "light grey" :extend t))
     (((class color))
@@ -1108,8 +1120,10 @@ ediff-odd-diff-face-B
 (defface ediff-odd-diff-C
   '((((type pc))
      (:foreground "yellow3" :background "gray40" :extend t))
-    (((class color) (min-colors 88))
-     (:background "Grey" :extend t))
+    (((class color) (min-colors 88) (background light))
+     (:distant-foreground "Black" :background "Grey" :extend t))
+    (((class color) (min-colors 88) (background dark))
+     (:distant-foreground "White" :background "dim grey" :extend t))
     (((class color) (min-colors 16))
      (:foreground "White" :background "Grey" :extend t))
     (((class color))