Hide line below search bar in dark themes

The results return an empty div with a background color set (not sure
why, not generated on Whoogle's side). This unsets the background color
so that at least it isn't visible.

app/static/css/light-theme.css

@@ -45,6 +45,10 @@ select {
     box-shadow: 0 1px 6px rgba(32,33,36,0.28) !important;
 }
 
+.BsXmcf {
+    background-color: unset !important;
+}
+
 .BVG0Nb {
     background-color: var(--whoogle-result-bg) !important;
 }