--- a/browser/themes/shared/customizableui/customizeMode.inc.css
+++ b/browser/themes/shared/customizableui/customizeMode.inc.css
@@ -112,35 +112,40 @@
   background-color: -moz-field;
   color: -moz-fieldText;
 %endif
   text-shadow: none;
 }
 
 #customization-palette,
 #customization-empty {
-  padding: 5px 25px 25px;
+  padding: 5px 20px 20px;
 }
 
 #customization-header {
+%ifdef MOZ_PHOTON_THEME;
+  border-bottom: 1px solid ThreeDLightShadow;
   font-size: 1.75em;
   line-height: 1.75em;
   color: GrayText;
   font-weight: 200;
-  margin: 25px 25px 12px;
   padding-bottom: 12px;
-  border-bottom: 1px solid ThreeDLightShadow;
+%else
+  font-weight: 600;
+  font-size: 1.2em;
+%endif
+  margin: 20px 20px 15px;
 }
 
 #customization-panel-container {
 %ifndef MOZ_PHOTON_THEME
   padding: 15px 25px 25px;
   background-image: linear-gradient(to bottom, #3e86ce, #3878ba);
 %else
-  padding: 0 25px 25px;
+  padding: 0 20px 25px;
 %endif
 }
 
 %ifndef MOZ_PHOTON_THEME
 #main-window:-moz-any([customize-entering],[customize-entered]) #browser-bottombox,
 #customization-footer {
   background-color: -moz-dialog;
 }
@@ -328,17 +333,17 @@ toolbarpaletteitem[place="toolbar"] {
   margin-left: 0;
 }
 #widget-overflow-fixed-list > toolbarpaletteitem[place="panel"] {
   border-top: 0px solid transparent;
   border-bottom: 0px solid transparent;
 }
 
 #customization-palette:not([hidden]) {
-  margin-bottom: 25px;
+  margin-bottom: 20px;
 }
 
 toolbarpaletteitem[place="palette"]:-moz-focusring,
 toolbarpaletteitem[place="panel"]:-moz-focusring,
 toolbarpaletteitem[place="toolbar"]:-moz-focusring {
   outline-width: 0;
 }