Update listing.css

Using the style editor, unconventional though it may be, is a nice alternative to testing code commits that wouldn't actually fix anything because all the class headers were space-delimited instead of using a seperator that allows the CSS to select one particular element, like the title name for a file listing, without looking up the :not feature to deselect the header with the exact same .item class (thanks to https://stackoverflow.com/a/16202009 for helping find out how to single that out).

frontend/src/css/listing.css

@@ -195,7 +195,7 @@ html[dir="rtl"] #listing {
   align-items: center;
 }
 
-#listing.list .item p.name {
+#listing.list .item p.name:not(#listing.list .item.header .name) {
   margin-right: -3em;
 }