demo presentation now refers to correct zoom.js shortcut for linux #2280

demo.html

@@ -94,7 +94,7 @@
 						Press <strong>ESC</strong> to enter the slide overview.
 					</p>
 					<p>
-						Hold down alt and click on any element to zoom in on it using <a href="http://lab.hakim.se/zoom-js">zoom.js</a>. Alt + click anywhere to zoom back out.
+						Hold down the <strong>alt</strong> key (<strong>ctrl</strong> in Linux) and click on any element to zoom towards it using <a href="http://lab.hakim.se/zoom-js">zoom.js</a>. Click again to zoom back out.
 					</p>
 				</section>