試行錯誤

諦めそう

_sass/_header.scss

@@ -8,9 +8,12 @@ header {
   @include media-mobile {
     box-shadow: $header-mobile-box-shadow;
     position: fixed;
-    text-align: center;
     width: 100%;
     z-index: 9999;
+
+    a {
+      text-align: center;
+    }
   }
 
   a {
@@ -25,6 +28,7 @@ header {
     }
 
     > amp-img {
+      float: left;
       margin: $header-img-vertical-adjustment 1em 0 0;
     }
   }