Minor updates

assets/articles/intro.html

@@ -30,12 +30,12 @@
     The compound expression <code><span class="numbat-value">3</span> <span class="numbat-unit">months</span> + <span class="numbat-value">2</span> <span class="numbat-unit">years</span></code> is therefore well-typed:
     </p>
 
-    <div id="editor1" class="code-editor">3 months + 2 years</div>
+    <div id="editor1" class="code-editor">3 months + 2 years    # you can edit these examples!</div>
     <pre id="output1" class="numbat-output"></pre>
 
     <p>
     On the other hand, <code><span class="numbat-value">3</span> <span class="numbat-unit">months</span> + <span class="numbat-value">2</span> <span class="numbat-unit">lightyears</span></code> is <em>ill</em>-typed, because the right-hand side is of type <code class="numbat-type-identifier">Length</code>.
-    You can change &lsquo;years&rsquo; to &lsquo;lightyears&rsquo; in the example above to see the resulting compiler error.
+    You can change &lsquo;years&rsquo; to &lsquo;lightyears&rsquo; in the editor above to see the resulting compiler error.
     </p>
 
     <p>

assets/articles/main.css

@@ -14,7 +14,7 @@ body {
 h1,
 h2,
 h3 {
-    font-family: 'Lator', sans-serif;
+    font-family: 'Lato', sans-serif;
     color: #3e454c;
 }