properly reset button.close styles

scss/_close.scss

@@ -19,16 +19,16 @@
     cursor: pointer;
     opacity: .5;
   }
+}
 
-  // Additional properties for button version
-  // iOS requires the button element instead of an anchor tag.
-  // If you want the anchor version, it requires `href="#"`.
-  // See https://developer.mozilla.org/en-US/docs/Web/Events/click#Safari_Mobile
-  &button {
+// Additional properties for button version
+// iOS requires the button element instead of an anchor tag.
+// If you want the anchor version, it requires `href="#"`.
+// See https://developer.mozilla.org/en-US/docs/Web/Events/click#Safari_Mobile
+button.close {
   padding: 0;
   cursor: pointer;
   background: transparent;
   border: 0;
   -webkit-appearance: none;
-  }
 }