diff --git a/thirdeye/thirdeye-frontend/app/styles/components/rootcause-chart.scss b/thirdeye/thirdeye-frontend/app/styles/components/rootcause-chart.scss
index fabd0b72421..31930fb60b2 100644
--- a/thirdeye/thirdeye-frontend/app/styles/components/rootcause-chart.scss
+++ b/thirdeye/thirdeye-frontend/app/styles/components/rootcause-chart.scss
@@ -5,6 +5,10 @@
   &__title {
     padding-left: 16px;
   }
+
+  g[class*='c3-target-frontend-metric-baseline'] > .c3-lines {
+    stroke-dasharray: 1%;
+  }
 }
 
 .c3-line {