diff --git a/css/80_app.css b/css/80_app.css
index 1e00ff1..6c21369 100644
--- a/css/80_app.css
+++ b/css/80_app.css
@@ -3,7 +3,7 @@
 /* the root element of iD */
 .ideditor {
     height: 100%;
-    width: 80%;
+    width: 100%;
     margin: 0;
     padding: 0;
     border: 0;
@@ -4406,7 +4406,7 @@ img.tile-debug {
     bottom: 0;
     overflow: hidden;
     height: 100%;
-    width: 100%;
+    width: 80%;
     background: #000;
     user-select: none;
     touch-action: none;
diff --git a/dist/iD.css b/dist/iD.css
index fa58ec3..20ea456 100644
--- a/dist/iD.css
+++ b/dist/iD.css
@@ -3507,7 +3507,7 @@
 /* the root element of iD */
 .ideditor {
     height: 100%;
-    width: 80%;
+    width: 100%;
     margin: 0;
     padding: 0;
     border: 0;
@@ -7938,7 +7938,7 @@
     bottom: 0;
     overflow: hidden;
     height: 100%;
-    width: 100%;
+    width: 80%;
     background: #000;
     -webkit-user-select: none;
        -moz-user-select: none;