diff --git a/res/docpdf/make_htmldoc.py b/res/docpdf/make_htmldoc.py
index dc48195aa..18be36d73 100644
--- a/res/docpdf/make_htmldoc.py
+++ b/res/docpdf/make_htmldoc.py
@@ -130,6 +130,10 @@ if __name__ == "__main__":
       h1 {
         text-align: center;
       }
+
+      img {
+        max-width: 100%%;
+      }
     </style>
     <title>%s</title>
   </head>