Ban window now has a more appropriate window color

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

board/templates/admin/board/reportrecord/change_list.html

@@ -3,6 +3,10 @@
 {% block extrastyle %}
 {{ block.super }}
 <style>
+.winbox {
+    background: var(--border-color);
+}
+
 .field-post_body {
     width: 100%;
 }