diff --git a/themes/blue/theme.css b/themes/blue/theme.css
index 1b0ce87..5939ba3 100644
--- a/themes/blue/theme.css
+++ b/themes/blue/theme.css
@@ -176,7 +176,7 @@ input[type=button], input[type=submit]{
 .link-display{
 	margin-left:0.5rem;
 }
-audio, video, img{
+audio, video, img, iframe{
 	max-width:100%;
 }
 object {
diff --git a/themes/default/theme.css b/themes/default/theme.css
index 9d89dc2..268c076 100644
--- a/themes/default/theme.css
+++ b/themes/default/theme.css
@@ -155,7 +155,7 @@ input[type=button], input[type=submit] { cursor: pointer; }
 .link-display { margin-left: 0.5rem; }
 .button { appearance: button; -moz-appearance: button; -webkit-appearance: button; text-decoration: none; font-size: 0.9em; }
 
-audio, video, img { max-width: 100%; }
+audio, video, img, iframe { max-width: 100%; }
 object { width: 100%; height: 90vh; }
 figure:not(.preview) { display: inline-block; }
 figure:not(.preview) > :first-child { display: block; }