diff --git a/src/sass/gtk/_common-3.0.scss b/src/sass/gtk/_common-3.0.scss
index cba6457..f5a380a 100644
--- a/src/sass/gtk/_common-3.0.scss
+++ b/src/sass/gtk/_common-3.0.scss
@@ -1401,8 +1401,9 @@ actionbar {
     background-color: darken($bg_color, 3%);
   }
 
-  .background.csd revealer > & > revealer > box,
-  .background.csd > box.vertical > & > revealer > box {
+  // .background.csd revealer > & > revealer > box,
+  .background.csd > box.vertical > & > revealer > box,
+  .background.csd > box > box > box > & > revealer > box {
     border-radius: 0 0 $wm_radius $wm_radius;
   }
 }
diff --git a/src/sass/gtk/apps/_gnome-3.22.scss b/src/sass/gtk/apps/_gnome-3.22.scss
index ca0439f..07f8803 100644
--- a/src/sass/gtk/apps/_gnome-3.22.scss
+++ b/src/sass/gtk/apps/_gnome-3.22.scss
@@ -2855,6 +2855,16 @@ window#GearyMainWindow.background.csd { // <= 3.32
           }
         }
       }
+
+      geary-composer-editor {
+        > box.background {
+          background-color: transparent;
+
+          > actionbar > revealer > box {
+            border-radius: 0 0 7px 7px;
+          }
+        }
+      }
     }
 
     searchbar {
@@ -2866,6 +2876,18 @@ window#GearyMainWindow.background.csd { // <= 3.32
   }
 }
 
+geary-composer-box.background.csd {
+  geary-composer-editor {
+    > box.background {
+      background-color: transparent;
+
+      > actionbar > revealer > box {
+        border-radius: 0 0 $wm_radius $wm_radius;
+      }
+    }
+  }
+}
+
 // Accounts setting dialog
 .geary-accounts-editor-pane-content {
   frame:not(.geary-signature) {