It seems that you have animations disabled on your OS, turning Animate.css off code example
Example: animate.css not working
<html>
<head>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.7.0/animate.min.css"/>
</head>
<body>
<h2 class="animated slideInLeft" style="animation-delay:1s">Your ultimate Solution</h2>
</body>
</html>