diff --git a/js/drag-and-drop.js b/js/drag-and-drop.js
index 53227e0..213550c 100644
--- a/js/drag-and-drop.js
+++ b/js/drag-and-drop.js
@@ -43,8 +43,8 @@
       var x = event.clientX;
       var y = event.clientY;
       var point = moveObj.getBoundingClientRect();
-      width = x - point.left + (document.documentElement.clientWidth/20); //
-      height = y - point.top + (document.documentElement.clientHeight/18);
+      width = x - point.left + (document.documentElement.clientWidth/20); //ポップアップ内の位置と画面全体の位置の差を計算
+      height = y - point.top + (document.documentElement.clientHeight/20) + ((document.documentElement.clientHeight - document.documentElement.clientWidth)/20);
       console.log(x + ", " + y + ", " + point.left + ", " + point.top);
       document.addEventListener("mousemove",onMouseMove);
     }