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<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.7.0/animate.min.css"/>
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<h2 class="animated slideInLeft" style="animation-delay:1s">Your ultimate Solution</h2>
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Can you check those OS settings and confirm that the animations are not turned off?
OSX: Settings > General > Accessibility > Reduce Motion
IOS: System Preferences > Accessibility > Display > Reduce Motion
Windows: Settings > Ease of Access > Show animations in Windows