diff --git a/css/ssSearch.css b/css/ssSearch.css
index df672c63..3e5da00d 100644
--- a/css/ssSearch.css
+++ b/css/ssSearch.css
@@ -13,6 +13,10 @@
  * search form elements and search results on 
  * the search page. */
 
+body{
+    --invalid-input-color: #ffc0cb;
+}
+
 form#ssForm{
     display: flex;
     flex-direction: column;
@@ -30,6 +34,10 @@ input.staticSearch_feat:disabled{
   cursor: wait;
 }
 
+input:invalid{
+    background-color: var(--invalid-input-color);
+}
+
 /* Visually hide elements necessary for accessibility */
 fieldset.ssFieldset > legend.sr-only{
      position: absolute;