Link to Markdown syntax instructions

Author: greenberga

src/components/InstructionsEditor.jsx

@@ -47,7 +47,14 @@ export default class InstructionsEditor extends React.Component {
           />
         </div>
         <div className="instructions-editor__footer">
-          Styling with Markdown is supported
+          <a
+            className="instructions-editor__footer-link"
+            href="https://guides.github.com/features/mastering-markdown/"
+            rel="noopener noreferrer"
+            target="_blank"
+          >
+            Styling with Markdown is supported
+          </a>
         </div>
       </div>
     );

src/css/application.css

@@ -395,6 +395,10 @@ body {
   font-size: 0.875rem;
 }
 
+.instructions-editor__footer-link {
+  color: black;
+}
+
 .instructions-editor__menu-button:not(:last-child) {
   margin-right: 0.5em;
 }