Added `.term-bold` declaration.

app/assets/stylesheets/pages/xterm.scss

@@ -20,6 +20,9 @@
   $l-cyan: #8abeb7;
   $l-white: $ci-text-color;
 
+  .term-bold {
+    font-weight: bold;
+  }
   .term-italic {
     font-style: italic;
   }