No inline styling

client/coral-embed-stream/src/components/CommentTombstone.css

@@ -0,0 +1,6 @@
+.commentTombstone {
+  background-color: #F0F0F0;
+  text-align: center;
+  padding: 1em;
+  color: #3E4F71;
+}

client/coral-embed-stream/src/components/CommentTombstone.js

@@ -1,6 +1,7 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 import t from 'coral-framework/services/i18n';
+import styles from './CommentTombstone.css';
 
 // Render in place of a Comment when the author of the comment is <action>
 class CommentTombstone extends React.Component {
@@ -19,14 +20,9 @@ class CommentTombstone extends React.Component {
 
   render() {
     return (
-      <div>
+      <div className="talk-comment-tombstone">
         <hr aria-hidden={true} />
-        <p style={{
-          backgroundColor: '#F0F0F0',
-          textAlign: 'center',
-          padding: '1em',
-          color: '#3E4F71',
-        }}>
+        <p className={styles.commentTombstone}>
           {this.getCopy()}
         </p>
       </div>