Remove box shadow and padding around preview html element

packages/builder/src/components/design/AppPreview/iframeTemplate.js

@@ -17,18 +17,14 @@ export default `
         margin: 0;
       }
       html {
-        height: calc(100% - 16px);
+        height: 100%;
-        width: calc(100% - 16px);
+        width: 100%;
         overflow: hidden;
-        margin: 8px;
         display: flex;
         flex-direction: column;
         justify-content: flex-start;
         align-items: stretch;
       }
-      html.loaded {
-        box-shadow: 0 2px 8px -2px rgba(0, 0, 0, 0.1);
-      }
       body {
         flex: 1 1 auto;
         overflow: hidden;