diff --git a/static/css/contents/sphinx.css b/static/css/contents/sphinx.css
index e437c9a..060d453 100644
--- a/static/css/contents/sphinx.css
+++ b/static/css/contents/sphinx.css
@@ -26,6 +26,14 @@
   width: 30%;
 }
 
+@media (max-width: 767px) {
+  .yue .sidebar {
+    float: none;
+    width: 100%;
+    margin-left: 0;
+  }
+}
+
 .yue .sidebar > * {
   padding-left: 1rem;
   padding-right: 1rem;