diff --git a/inst/rmarkdown/templates/posterdown_ids/resources/template.html b/inst/rmarkdown/templates/posterdown_ids/resources/template.html
index 5b929e1..22ae0ed 100644
--- a/inst/rmarkdown/templates/posterdown_ids/resources/template.html
+++ b/inst/rmarkdown/templates/posterdown_ids/resources/template.html
@@ -272,6 +272,10 @@
 margin-block-end: 0.25em;
 }
 
+.poster_body img {
+  width: 100%;
+}
+
 .footnotes {
   font-family: Fira Sans Condensed;
 }