diff --git a/data/ui/event-widget.ui b/data/ui/event-widget.ui
index f98b09ea..e75345c9 100644
--- a/data/ui/event-widget.ui
+++ b/data/ui/event-widget.ui
@@ -22,6 +22,10 @@
               <object class="GtkBox" id="color_box">
                 <property name="visible">True</property>
                 <property name="can_focus">False</property>
+                <property name="halign">center</property>
+                <property name="valign">center</property>
+                <property name="width-request">16</property>
+                <property name="height-request">16</property>
                 <style>
                   <class name="icon-box" />
                 </style>