diff --git a/slides/gen_index.sh b/slides/gen_index.sh
index fae87f02a717c2f25be21ca985cea43db447eb28..15bc62f8d4db616969e292c08de4ae9fe53e655f 100755
--- a/slides/gen_index.sh
+++ b/slides/gen_index.sh
@@ -38,7 +38,7 @@ for i in *.md; do
         fail "Error title field not found"
     fi
     i="${i%.*}"
-    class="[${date} ${comp}](${PREFIX}${i}.pdf)"
+    class="[${date}: ${comp}](${PREFIX}${i}.pdf)"
     classes+=("$class")
 done
 IFS=$'\n'