Lightweight Scroll Animation Library – sal.js

<script type="text/javascript" src="sal.js"></script>

 <div class="item"></div>

window.onload = () => {
    window.SAL = sal({
        threshold: 0.0001, // Viewport block percentage
        once: false, // Animate only the first time or constantly
        selector: '.item', // Block selector for animation
        animateClassName: 'item_animate', // Animation class hanging on blocks falling into viewport
        disabledClassName: 'item_disabled', // Class hanging on body when sal.disable()
    });

    // Smooth scroll
    // (scroll element, scroll value, inertia)
    window.SS = new SmoothScroll(document, 70, 8);
}