show only most recent if not searching, visibility

layouts/shortcodes/artlist.html

@@ -1,5 +1,7 @@
 <ul id=artlist>
-{{range.Site.RegularPages}}
-<li data-tags="{{.Params.Tags}}"><a href="{{.Permalink}}">{{.Title}}</a></li>
-{{end}}
+{{ $number := 0 -}}
+{{- range.Site.RegularPages -}}
+{{- $number = add $number 1 -}}
+<li data-tags="{{.Params.Tags}}" {{ if gt $number .Site.Params.indexarticles }}class="older-article"{{ end }}><a href="{{.Permalink}}">{{.Title}}</a></li>
+{{ end -}}
 </ul>