Get element by class name in AngularJs

<!DOCTYPE html>
<html lang="en">
<head>
 <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.2.13/angular.min.js"></script>
 

<!DOCTYPE html>
<html lang="en">
<head>
 <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.2.13/angular.min.js"></script>
 <script>
var myApp = angular.module("myApp", []);
 myApp.controller("myController", function($scope) {
$scope.getClassElm = function() {
	 var element = angular.element(document.querySelector(".myPara"));
          element.css('color', 'blue');
	 
};
});
</script>
</head>
<body>  
<div ng-app="myApp">  
<div ng-controller="myController">  
<h3>AngularJs Is Cool!</h3>
<p class="myPara">
This is test paragraph....
</p>
<input type="button" value="Change Paragraph Color " ng-click="getClassElm()"> 
</div> 

</body>  
</html>