💄 Optimize attachment preview

lib/screens/posts/compose_article.dart

@@ -309,6 +309,8 @@ class ArticleComposeScreen extends HookConsumerWidget {
                       onExpansionChanged: (expanded) {
                         isAttachmentsExpanded.value = expanded;
                       },
+                      collapsedBackgroundColor:
+                          Theme.of(context).colorScheme.surfaceContainer,
                       title: Column(
                         crossAxisAlignment: CrossAxisAlignment.start,
                         children: [

lib/widgets/content/attachment_preview.dart

@@ -363,7 +363,7 @@ class AttachmentPreview extends HookConsumerWidget {
                     ),
                 ],
               ),
-            ),
+            ).center(),
             Row(
               mainAxisAlignment: MainAxisAlignment.spaceBetween,
               children: [