diff --git a/src/day8/re_frame/trace/styles.cljs b/src/day8/re_frame/trace/styles.cljs
index d04cdd7..28dec04 100644
--- a/src/day8/re_frame/trace/styles.cljs
+++ b/src/day8/re_frame/trace/styles.cljs
@@ -156,6 +156,7 @@
     [(s/& ".trace--sub-run")
      [".trace--op" {:color dark-purple}]]
     [(s/& ".trace--event")
+     {:border-top [["1px" light-gray "solid"]]}
      [".trace--op" {:color common/event-color}]]
     [(s/& ".trace--render")
      [".trace--op" {:color dark-skyblue}]]