Fixing language

physics/demo.html

@@ -68,7 +68,7 @@
 			<h2>Ball Drop Physics</h2>
 			<p>This is a simple demo that uses the Processing.js library and the HTML5 canvas element.</p>
 			<p>The physics are very simple, and the code can be viewed using your browser.</p>
-			<p>Click anywhere in the black area to drop the ball from that position.</p>
+			<p>Click anywhere in the blue background area to drop the ball from that position.</p>
 		</div>
 		<canvas height="600" width="600"></canvas>
 	</body>