use margin instead of padding for nice background color

src/vs/workbench/browser/parts/editor/media/breadcrumbscontrol.css

@@ -18,12 +18,12 @@
 
 .monaco-workbench>.part.editor>.content .editor-group-container .breadcrumbs-control .monaco-breadcrumbs .monaco-breadcrumb-item:nth-child(2) {
 	/*first-child is the style-element*/
-	padding-left: 8px;
+	margin-left: 8px;
 }
 
 .monaco-workbench>.part.editor>.content .editor-group-container .breadcrumbs-control .monaco-breadcrumbs .monaco-breadcrumb-item:last-child {
 	/*first-child is the style-element*/
-	padding-right: 8px;
+	margin-right: 8px;
 }
 
 .monaco-breadcrumbs-picker {