Tweak spacing in select items dialog

chrome/content/zotero/selectItemsDialog.xhtml

@@ -44,15 +44,13 @@
 	style="display: flex"
 >
 <dialog
+	id="select-items-dialog"
 	orient="vertical"
 	buttons="cancel,accept"
-		style="padding: 2em"
 >
 <script>
 	var {Services} = ChromeUtils.import("resource://gre/modules/Services.jsm");
-			
 	Services.scriptloader.loadSubScript("chrome://zotero/content/include.js", this);
-
 	Services.scriptloader.loadSubScript("chrome://zotero/content/selectItemsDialog.js", this);
 	
 	// Custom elements
@@ -60,21 +58,17 @@
 </script>
 
 <vbox id="zotero-select-items-container" flex="1">
-
-		<hbox align="center" pack="end">
+	<hbox id="search-toolbar">
 		<quick-search-textbox id="zotero-tb-search" timeout="250" oncommand="onSearch()" dir="reverse"/>
 	</hbox>
-
-		<hbox flex="1">
-			<vbox id="zotero-collections-tree-container" class="virtualized-table-container" style="min-width: 200px">
+	<hbox id="collections-items-container">
+		<vbox id="zotero-collections-tree-container" class="virtualized-table-container">
 			<html:div id="zotero-collections-tree"></html:div>
 		</vbox>
-
 		<hbox id="zotero-items-pane-content" class="virtualized-table-container" flex="1">
 			<html:div id="zotero-items-tree"></html:div>
 		</hbox>
 	</hbox>
-
 </vbox>
 </dialog>
 </window>

scss/_zotero.scss

@@ -41,6 +41,7 @@
 @import "components/publications-dialog";
 @import "components/rtfScan.scss";
 @import "components/search";
+@import "components/selectItemsDialog";
 @import "components/spinner";
 @import "components/syncButtonTooltip";
 @import "components/tabBar";

scss/components/_selectItemsDialog.scss

@@ -0,0 +1,28 @@
+#select-items-dialog {
+    padding: 2em;
+
+    #zotero-select-items-container {
+        display: flex;
+        flex-direction: column;
+        gap: 8px;
+    }
+
+    #zotero-collections-tree-container {
+        min-width: 200px;
+    }
+
+    #search-toolbar {
+        display: flex;
+        flex-direction: row;
+        justify-content: flex-end;
+    }
+
+    #search-toolbar {
+        flex: 0 0 auto;
+    }
+
+    #collections-items-container {
+        flex: 1 1 auto;
+        margin-bottom: 8px;
+    }
+}