Update README.md

Author: learning-zone

README.md

@@ -1672,11 +1672,11 @@ socket.addEventListener('message', function(event) {
 
 ```html
 <div>Rectangle with Style</div>
-<canvas id="rect">This browser does not support Canvas!</canvas>
+<canvas id="rectangle" width="300" height="200" style="border: 1px solid #999;"></canvas>
 
 <script type="text/javascript">
  // Rectange with style
- var canvas = document.getElementById("rect");
+ var canvas = document.getElementById("rectangle");
  var context = canvas.getContext("2d");
  context.fillStyle = "#FF0000";
  context.fillRect(0, 0, 300, 200);