diff --git a/assets/index.html b/assets/index.html
index b6c7cdd..81c9e39 100644
--- a/assets/index.html
+++ b/assets/index.html
@@ -17,7 +17,7 @@
     var ctx = c.getContext('2d');
     var W, H;
     var TILE = 32;
-    var GAP = 1;
+    var GAP = 0;
     var HEIGHT_UNIT = 6;
 
     function resize() {