diff --git a/theme/html/default.css b/theme/html/default.css
index 8f22850..f69a914 100644
--- a/theme/html/default.css
+++ b/theme/html/default.css
@@ -210,4 +210,19 @@ body {
 
 .sidenote_ref {
   cursor: pointer;
-}
\ No newline at end of file
+}
+
+figure {
+ display: block;
+}
+
+figure img {
+  margin: 0px auto;
+  display: block;
+}
+
+figure img + figcaption {
+  margin: 0px auto;
+  display: block;
+  text-align: center;
+}