diff --git a/gtk/theme/Adwaita/_common.scss b/gtk/theme/Adwaita/_common.scss
index 270784bb5d..b33455d539 100644
--- a/gtk/theme/Adwaita/_common.scss
+++ b/gtk/theme/Adwaita/_common.scss
@@ -3783,7 +3783,7 @@ window {
   &.solid-csd {
     margin: 0;
     padding: 0;
-    border: solid 14px $borders_color;
+    border: solid 1px $borders_color;
     border-radius: 0;
     box-shadow: inset 0 0 0 3px $headerbar_color, inset 0 1px $top_hilight;