diff --git a/inst/rmarkdown/templates/posterdown_ids/resources/template.html b/inst/rmarkdown/templates/posterdown_ids/resources/template.html
index b953304..4d5c996 100644
--- a/inst/rmarkdown/templates/posterdown_ids/resources/template.html
+++ b/inst/rmarkdown/templates/posterdown_ids/resources/template.html
@@ -222,6 +222,9 @@
 img {
 margin-top: 0;
 margin-bottom: 0;
+margin-left: auto;
+margin-right: auto;
+display: block;
 }
 .section {
   padding: 0.2em;
@@ -361,6 +364,10 @@
 }
 caption {
 margin-bottom: 10px;
+margin-left: auto;
+margin-right: auto;
+display: block;
+width: fit-content;
 }
 .poster_body p, ol, ul {
 margin-top: 2mm;