<div class="tinder">


  <div class="tinder--cards">
    <div class="tinder--card">
      <img src="https://placeimg.com/600/700/people">
<!--       <h3>Demo card 1</h3>
      <p>This is a demo for Tinder like swipe cards</p> -->
    </div>
    <div class="tinder--card">
      <img src="https://placeimg.com/600/700/animals">
<!--       <h3>Demo card 2</h3>
      <p>This is a demo for Tinder like swipe cards</p> -->
    </div>
    <div class="tinder--card">
      <img src="https://placeimg.com/600/700/nature">
<!--       <h3>Demo card 3</h3>
      <p>This is a demo for Tinder like swipe cards</p> -->
    </div>
    <div class="tinder--card">
      <img src="https://placeimg.com/600/700/tech">
<!--       <h3>Demo card 4</h3>
      <p>This is a demo for Tinder like swipe cards</p> -->
    </div>
    <div class="tinder--card">
      <img src="https://placeimg.com/600/700/arch">
<!--       <h3>Demo card 5</h3>
      <p>This is a demo for Tinder like swipe cards</p> -->
    </div>
  </div>


</div>

*, *:before, *:after {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

body {
  background: black;
  overflow: hidden;
  font-family: sans-serif;
}

.tinder {
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  position: relative;
/*   opacity: 0; */
  transition: opacity 0.1s ease-in-out;
}

.loaded.tinder {
  opacity: 1;
}

.tinder--status {
  position: absolute;
  top: 50%;
  margin-top: -30px;
  z-index: 2;
  width: 100%;
  text-align: center;
  pointer-events: none;
}

.tinder--status i {
  font-size: 100px;
  opacity: 0;
  transform: scale(0.3);
  transition: all 0.2s ease-in-out;
  position: absolute;
  width: 100px;
  margin-left: -50px;
}

.tinder_love .fa-heart {
  opacity: 0.7;
  transform: scale(1);
}

.tinder_nope .fa-remove {
  opacity: 0.7;
  transform: scale(1);
}

.tinder--cards {
  flex-grow: 1;
  padding-top: 40px;
  text-align: center;
  display: flex;
  justify-content: center;
  align-items: flex-end;
  z-index: 1;
}

.tinder--card {
  display: inline-block;
  width: 90vw;
  max-width: 400px;
  height: 70vh;
  background: #FFFFFF;
  padding-bottom: 40px;
  border-radius: 8px;
  overflow: hidden;
  position: absolute;
  will-change: transform;
  transition: all 0.3s ease-in-out;
  cursor: -webkit-grab;
  cursor: -moz-grab;
  cursor: grab;
}

.moving.tinder--card {
  transition: none;
  cursor: -webkit-grabbing;
  cursor: -moz-grabbing;
  cursor: grabbing;
}

.transition-off.tinder--card {
  transition: none;
}

.tinder--card img {
  max-width: 100%;
  pointer-events: none;
}

.tinder--card h3 {
  margin-top: 32px;
  font-size: 32px;
  padding: 0 16px;
  pointer-events: none;
}

.tinder--card p {
  margin-top: 24px;
  font-size: 20px;
  padding: 0 16px;
  pointer-events: none;
}

.tinder--buttons {
  flex: 0 0 100px;
  text-align: center;
  padding-top: 20px;
}

.tinder--buttons button {
  border-radius: 50%;
  line-height: 60px;
  width: 60px;
  border: 0;
  background: #FFFFFF;
  display: inline-block;
  margin: 0 8px;
}

.tinder--buttons button:focus {
  outline: 0;
}

.tinder--buttons i {
  font-size: 32px;
  vertical-align: middle;
}

.fa-heart {
  color: red;
}

.fa-remove {
  color: black;
}

"use strict";

function lerp(v0, v1, t) {
  return (1 - t) * v0 + t * v1;
}

function onNextFrame(cb) {
  requestAnimationFrame(() => requestAnimationFrame(cb));
}

const tinderContainer = document.querySelector(".tinder");
const allCards = Array.from(
  tinderContainer.querySelectorAll(".tinder--card"),
  (el, index) => ({ el, index })
);

let currentCard = 0;

function updateCards(cards, currentCardIndex) {
  cards.forEach((card) => {
    const dist = (card.index - currentCardIndex + allCards.length) % allCards.length;
    const f = dist / allCards.length;
    const scale = lerp(1, 0.75, f);
    const ty = lerp(0, -30 * allCards.length, f);
    const opacity = lerp(1, 0, f);
    card.el.style.zIndex = -dist;
    card.el.style.transform = `scale(${scale}) translateY(${ty}px)`;
    card.el.style.opacity = opacity;
  });
}

updateCards(allCards, currentCard);

allCards.forEach(function ({el}) {
  var hammertime = new Hammer(el);

  hammertime.on("pan", function (event) {
    el.classList.add("moving");
  });

  hammertime.on("pan", function (event) {
    if (event.deltaX === 0) return;
    if (event.center.x === 0 && event.center.y === 0) return;

    var xMulti = event.deltaX * 0.03;
    var yMulti = event.deltaY / 80;
    var rotate = xMulti * yMulti;

    event.target.style.transform =
      "translate(" +
      event.deltaX +
      "px, " +
      event.deltaY +
      "px) rotate(" +
      rotate +
      "deg)";
  });

  hammertime.on("panend", function (event) {
    el.classList.remove("moving");

    var moveOutWidth = document.body.clientWidth;
    var keep = Math.abs(event.deltaX) < 80 || Math.abs(event.velocityX) < 0.5;

    // event.target.classList.toggle("removed", !keep);

    if (keep || !keep) {
      var endX = Math.max(
        Math.abs(event.velocityX) * moveOutWidth,
        moveOutWidth
      );
      var toX = event.deltaX > 0 ? endX : -endX;
      var endY = Math.abs(event.velocityY) * moveOutWidth;
      var toY = event.deltaY > 0 ? endY : -endY;
      var xMulti = event.deltaX * 0.03;
      var yMulti = event.deltaY / 50;
      var rotate = xMulti * yMulti;

      event.target.style.transform =
        "translate(" +
        toX +
        "px, " +
        (toY + event.deltaY) +
        "px) rotate(" +
        rotate +
        "deg)";
      
      currentCard = (currentCard + 1) % allCards.length;
      
      event.target.addEventListener('transitionend', () => {
        event.target.classList.add('transition-off');
        updateCards(allCards, currentCard);
        onNextFrame(() => event.target.classList.remove('transition-off'));
      }, { once: true });
    }
  });
});