Card Details Header always at top of all other scrollable elements

client/components/cards/cardDetails.styl

@@ -112,6 +112,7 @@ avatar-radius = 50%
     border-bottom: 1px solid darken(white, 14%)
     position: sticky
     top: 0px
+    z-index: 500
 
     .card-number {
       color: darken(white, 30%);