Below is a diagram which labels the various selectors in a DiscussionApp Widget:

Below is the style sheet that was used for the table above. Feel free to copy and modify it.

body#widget {  
  padding:1%;  
}

table#widget_table { 
  margin:auto; 
  padding:1%;
  border:1px solid black;
  border-spacing:8px;
}

td {
  padding:4px;  
}

td.link_cell {
  background-color:#ccf;  
}

a:hover {
  background-color:#eee;
}

td.author_cell {
  border:1px dashed black;  
}

td.date_cell {
  background-color:#fcc;
  font-size:smaller;
}

You can also modify the widget's container on the calling page. Take the following-

<div style="width:30em; height:15em; margin:auto; padding:1ex; border:ridge 8px #ccc;">

 <div style="text-align:center;">Check out our new widget</div>

 <iframe src="discapp-widget-iframe.html" width="99%" height="99%" frameborder="no" scrolling="no"></iframe>

</div>

By enclosing the widget in a "div" container, you can adjust the height and width of the widget, place it on your page, and add a border around it.