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Back Out

The element steps back to a smaller size, as if moving into the distance, then glides off screen at that size. Pick the edge, or give several and a looping demo takes each in turn.

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How to use it

  1. Paste the snippet just before </head>.
  2. Add data-back-out to any element.
  3. Choose an edge with data-to if it shouldn’t leave by the bottom.

Options

Add any of these attributes to the same element.

data-toThe edge it leaves by: bottom, top, left or right. Give several and each loop uses the next. Default bottom.
data-scaleIts size as it leaves. Default 0.7.
data-distanceTravel this many px, fading out, instead of leaving the screen.
data-durationHow long it takes to leave. Default 1100 ms.
data-delayHow long it stays in view before it leaves. Default 1200 ms.
data-loopFade back in, hold and back out again.
data-holdHow long it stays between exits, when looping. Default 1400 ms.

It leaves past the edge of the nearest container that clips its overflow (overflow: hidden or clip), or of the window. Put it in a clipping wrapper, or give the page overflow-x: clip, so it can’t make the page scroll sideways on its way out. It ends hidden (visibility: hidden) but still taking up its space. To play it when you choose, leave the attribute off and call animacious.backOut(el).

1 · Snippet
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/bundles/anime.umd.min.js"></script>
<script>
  (function () {
    // Back Out: the element steps back to a smaller size, as if moving into
    // the distance, then glides off screen at that size.
    // Usage: <div data-back-out>…</div>
    // It plays once the element has been in view for data-delay ms. It leaves
    // past the edge of the nearest container that clips its overflow
    // (overflow: hidden or clip), or of the window, and ends hidden
    // (visibility: hidden) but still taking up its space.
    // Optional: data-to ("bottom", default, "top", "left" or "right"; give
    // several, like "bottom left top", and each loop uses the next),
    // data-scale (its size as it leaves, default 0.7), data-distance (px to
    // travel, fading out, instead of leaving the screen),
    // data-duration (ms, default 1100), data-delay (ms in view before it
    // leaves, default 1200), data-loop (fade back in, hold and back out
    // again), data-hold (ms to stay between exits when looping, default 1400).
    // Script use: animacious.backOut(el, done) plays it on any element now,
    // using its data-* options, and calls done afterwards.
    var DEFAULTS = { to: 'bottom', scale: 0.7, duration: 1100, delay: 1200, hold: 1400 };

    function reduced() {
      return window.matchMedia('(prefers-reduced-motion: reduce)').matches;
    }

    // The box the element must leave to be "off screen".
    function clipBox(el) {
      for (var p = el.parentElement; p && p !== document.body; p = p.parentElement) {
        var s = getComputedStyle(p);
        if (s.overflowX !== 'visible' || s.overflowY !== 'visible') return p.getBoundingClientRect();
      }
      return { left: 0, top: 0, right: window.innerWidth, bottom: window.innerHeight };
    }

    function leave(el, to, done) {
      var d = el.dataset;
      var t = +d.duration || DEFAULTS.duration;
      if (reduced()) {
        anime.utils.set(el, { opacity: 0 });
        if (done) done();
        return;
      }
      var sc = +d.scale || DEFAULTS.scale;
      anime.utils.set(el, { x: 0, y: 0, scale: 1 });
      var dist = +d.distance;
      var r = el.getBoundingClientRect();
      var c = clipBox(el);
      // Its shrunken box is smaller, so it needs less travel to clear the edge.
      var gapX = r.width * (1 - sc) / 2;
      var gapY = r.height * (1 - sc) / 2;
      var o = { x: 0, y: 0 };
      if (to === 'top') o.y = -(dist || r.bottom - gapY - c.top + 8);
      else if (to === 'left') o.x = -(dist || r.right - gapX - c.left + 8);
      else if (to === 'right') o.x = dist || c.right - r.left - gapX + 8;
      else o.y = dist || c.bottom - r.top - gapY + 8;
      anime.animate(el, {
        // Step back first, a little dimmer, then go.
        scale: { to: sc, duration: t * 0.35, ease: 'inOut(2)' },
        x: { to: o.x, delay: t * 0.35, duration: t * 0.65, ease: 'in(3)' },
        y: { to: o.y, delay: t * 0.35, duration: t * 0.65, ease: 'in(3)' },
        opacity: dist
          ? [{ to: 0.75, duration: t * 0.35, ease: 'out(2)' }, { to: 0, duration: t * 0.65, ease: 'in(2)' }]
          : { to: 0.75, duration: t * 0.35, ease: 'out(2)' },
        onComplete: function () {
          if (done) done();
        }
      });
    }

    function cycle(el) {
      var d = el.dataset;
      var s = el._bko;
      var list = (d.to || DEFAULTS.to).split(/[\s,]+/);
      leave(el, list[s.n++ % list.length], function () {
        if (d.loop === undefined || d.loop === 'false') {
          el.style.visibility = 'hidden';
          return;
        }
        // Come back quietly in place, then go again once it's on screen.
        setTimeout(function () {
          anime.utils.set(el, { x: 0, y: 0, scale: 1, opacity: 0 });
          anime.animate(el, {
            opacity: 1,
            duration: 400,
            ease: 'out(2)',
            onComplete: function () {
              setTimeout(function () {
                if (s.visible) cycle(el);
                else s.waiting = true;
              }, +d.hold || DEFAULTS.hold);
            }
          });
        }, 400);
      });
    }

    window.animacious = window.animacious || {};
    window.animacious.backOut = function (el, done) {
      leave(el, (el.dataset.to || DEFAULTS.to).split(/[\s,]+/)[0], function () {
        el.style.visibility = 'hidden';
        if (done) done(el);
      });
    };

    function init() {
      var io = new IntersectionObserver(function (entries) {
        entries.forEach(function (e) {
          var s = e.target._bko;
          s.visible = e.isIntersecting;
          if (!e.isIntersecting) return;
          if (!s.started) {
            s.started = true;
            var wait = e.target.dataset.delay;
            setTimeout(function () { cycle(e.target); }, wait === undefined ? DEFAULTS.delay : +wait || 0);
          } else if (s.waiting) {
            s.waiting = false;
            cycle(e.target);
          }
        });
      }, { threshold: 0.2 });
      document.querySelectorAll('[data-back-out]').forEach(function (el) {
        if (el._bko) return;
        el._bko = { n: 0 };
        if (!reduced()) io.observe(el);
      });
    }

    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', init);
    else init();
  })();
</script>
2 · Your HTML
<div class="card" data-back-out>Draft discarded</div>

<!-- or leaving by the left: -->
<div class="card" data-back-out data-to="left">Draft discarded</div>