To limit the width of the widget in the embedded page:

1) Add to the page you would like to embed the widget

<div class="my-app-class-with-width">
//   Place here the Opinion Stage script code

2) Add to your CSS file 

.my-app-class-with-width { width: 650px; } 

//   Replace 650px with the width you would like to have

Did this answer your question?