diff --git a/chrome/content/zotero-platform/mac/overlay.css b/chrome/content/zotero-platform/mac/overlay.css
index b449bf6d5..4f0bef145 100644
--- a/chrome/content/zotero-platform/mac/overlay.css
+++ b/chrome/content/zotero-platform/mac/overlay.css
@@ -16,12 +16,17 @@
 	margin-left: 7px;
 }
 
-.zotero-tb-button {
-  -moz-margin-start: 5px;
-  -moz-padding-end: 10px;
+.zotero-tb-button, .zotero-tb-button:first-child, .zotero-tb-button:last-child {
+  -moz-margin-start: 0 !important;
+  -moz-margin-end: 3px !important;
+  -moz-padding-end: 10px !important;
   background: url("chrome://zotero/skin/mac/menubutton-end.png") right center no-repeat;
 }
 
+#zotero-collections-toolbar {
+	padding-left: 0;
+}
+
 :root:not([active]) #zotero-pane:not([ignoreActiveAttribute]) .zotero-tb-button, .zotero-tb-button[disabled="true"]{
 	opacity: 0.7;
 }
diff --git a/chrome/content/zotero-platform/win/overlay.css b/chrome/content/zotero-platform/win/overlay.css
index b9e239aeb..1313a941e 100644
--- a/chrome/content/zotero-platform/win/overlay.css
+++ b/chrome/content/zotero-platform/win/overlay.css
@@ -1,11 +1,3 @@
-.zotero-tb-button:not(:first-child) {
-	margin-left: 5px;
-}
-
-.zotero-tb-button:not([type=menu]) {
-	margin-right: 4px;
-}
-
 #zotero-tb-search-menu-button {
 	margin: 0 -1px 0 -4px;
 	border: 0;
diff --git a/chrome/content/zotero/zoteroPane.xul b/chrome/content/zotero/zoteroPane.xul
index 1081ce51e..36c90a9d3 100644
--- a/chrome/content/zotero/zoteroPane.xul
+++ b/chrome/content/zotero/zoteroPane.xul
@@ -98,7 +98,7 @@
 			chromedir="&locale.dir;">
 			
 			<toolbar id="zotero-toolbar" class="toolbar">
-				<hbox id="zotero-collections-toolbar">
+				<hbox id="zotero-collections-toolbar" align="center">
 					<toolbarbutton id="zotero-tb-collection-add" class="zotero-tb-button" tooltiptext="&zotero.toolbar.newCollection.label;" command="cmd_zotero_newCollection"/>
 					<toolbarbutton id="zotero-tb-group-add" class="zotero-tb-button" tooltiptext="&zotero.toolbar.newGroup;" oncommand="ZoteroPane_Local.newGroup()"/>
 					<spacer flex="1"/>
@@ -126,7 +126,7 @@
 					</toolbarbutton>
 				</hbox>
 				
-				<hbox id="zotero-items-toolbar">
+				<hbox id="zotero-items-toolbar" align="center">
 					<toolbarbutton id="zotero-tb-add" class="zotero-tb-button" tooltiptext="&zotero.toolbar.newItem.label;" type="menu">
 						<!-- New Item drop-down built in overlay.js::onLoad() -->
 						<menupopup onpopupshowing="ZoteroPane_Local.updateNewItemTypes()">
@@ -178,7 +178,7 @@
 							oncommand="ZoteroPane_Local.search()"/>
 				</hbox>
 				
-				<hbox id="zotero-item-toolbar" flex="1">
+				<hbox id="zotero-item-toolbar" flex="1" align="center">
 					<hbox align="center" pack="start" flex="1">
 						<toolbarbutton id="zotero-tb-locate" class="zotero-tb-button" tooltiptext="&zotero.toolbar.openURL.label;" type="menu">
 							<menupopup id="zotero-tb-locate-menu" onpopupshowing="Zotero_LocateMenu.buildLocateMenu()"/>
diff --git a/chrome/skin/default/zotero/overlay.css b/chrome/skin/default/zotero/overlay.css
index 8dee7c412..001ee60cf 100644
--- a/chrome/skin/default/zotero/overlay.css
+++ b/chrome/skin/default/zotero/overlay.css
@@ -33,7 +33,7 @@
 #zotero-pane
 {
 	min-height: 32px; /* must match value in ZoteroPane.updateTagSelectorSize() */
-	overflow: hidden;
+	overflow: hidden;tb-
 }
 
 #zotero-collections-pane
@@ -257,6 +257,32 @@
 	height:24px;
 }
 
+#zotero-collections-toolbar {
+	padding-left: 2px;
+}
+
+.zotero-tb-button {
+	padding-left: 5px;
+	padding-right: 5px;
+	margin-right: 2px;
+	margin-left: 2px;
+}
+
+.zotero-tb-button:first-child {
+	margin-left: 0 !important;
+}
+
+.zotero-tb-button:last-child {
+	margin-right: 0 !important;
+}
+
+.zotero-tb-button[type="menu"] {
+	padding-left: 3px;
+	padding-right: 3px;
+	margin-left: 4px;
+	margin-right: 2px;
+}
+
 .zotero-tb-button[type="panel"] > dropmarker {
   display: none;
 }
@@ -399,8 +425,9 @@
 
 #zotero-tb-sync {
 	list-style-image: url(chrome://zotero/skin/arrow_rotate_static.png);
-	margin-left: -2px;
+	margin-left: -6px;
 	margin-right: -2px;
+	padding-right: 6px;
 }
 
 #zotero-tb-sync[status=animate] {