diff --git a/_layouts/default.html b/_layouts/default.html
index c67e55b..8748736 100644
--- a/_layouts/default.html
+++ b/_layouts/default.html
@@ -38,8 +38,8 @@ layout: compress
         <!-- Wikiタイトル -->
         <a href="{{ site.github.url }}">
           <amp-img
-            height = "2.25em"
-            width  = "2.25em"
+            height = "2em"
+            width  = "2em"
             alt    = ""
             src    = "{{ site.github.url }}/images/icon.svg">
           </amp-img>
@@ -48,8 +48,8 @@ layout: compress
         <!-- モバイルメニュー表示ボタン -->
         <button on="tap:sidebar.open">
           <amp-img
-            height = "1.5em"
-            width  = "1.5em"
+            height = "2.25em"
+            width  = "2.25em"
             alt    = "メニュー"
             src    = "{{ site.github.url }}/images/menu.svg">
           </amp-img>