diff --git a/layouts/partials/highlightgroup.html b/layouts/partials/highlightgroup.html
index 0957d8d..31c41e3 100644
--- a/layouts/partials/highlightgroup.html
+++ b/layouts/partials/highlightgroup.html
@@ -1,9 +1,7 @@
-{{- if eq .language "Agda" -}}
-{{- page.Scratch.Set "highlightGroupAttrs" (printf "data-agda-block") -}}
 {{- if (or .firstLine .lastLine) -}}
-{{- page.Scratch.Add "highlightGroupAttrs" (printf " data-agda-first-line=\"%v\" data-agda-last-line=\"%v\"" .firstLine .lastLine) -}}
+{{- page.Scratch.Set "highlightGroupAttrs" (printf "data-first-line=\"%v\" data-last-line=\"%v\"" .firstLine .lastLine) -}}
 {{- end -}}
-{{- else -}}
-{{- page.Scratch.Set "highlightGroupAttrs" nil -}}
+{{- if eq .language "Agda" -}}
+{{- page.Scratch.Add "highlightGroupAttrs" " data-agda-block" -}}
 {{- end -}}
 {{ partial "group.html" (dict "url" .url "path" .path "comment" .comment "content" (highlight .code .language .opts) "attrs" (page.Scratch.Get "highlightGroupAttrs")) }}