JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container1 ">
	<div class="curtain1 remove">
		<div class="ratio-keeper">
			<div class="video-one"></div>
			<div class="wrap embed-youtube ">
				<div class="video embed-youtube  " data-id="djV11Xbc914">
				</div>
				<button class="playa cover embed-youtube-play" type="button" aria-label="Open"></button>
			</div>
		</div>

		<button class="exit exitpPage2" type="button" aria-label="Open"></button>
		<button class="exit exitpPage3" type="button" aria-label="Open"></button>
	</div>
</div>
<div class="container2 hide">
	<div class="container ">
		<div class="curtain remove">
			<div class="ratio-keeper">
				<div class="video-two"></div>
				<div class="wrap embed-youtube">
					<div class="video embed-youtube" data-id="djV11Xbc914">
					</div>
					<button class="playb cover embed-youtube-play" type="button" aria-label="Open"></button>
				</div>
			</div>
		</div>
		<div class="curtain remove">
			<div class="ratio-keeper">
				<div class="video-three"></div>
				<div class="wrap embed-youtube">
					<div class="video embed-youtube" data-id="djV11Xbc914">
					</div>
					<button class="playc cover embed-youtube-play" type="button" aria-label="Open"></button>
				</div>
			</div>
		</div>
		<div class="curtain remove">
			<div class="ratio-keeper">
				<div class="video-four"></div>
				<div class="wrap embed-youtube">
					<div class="video embed-youtube" data-id="djV11Xbc914">
					</div>
					<button class="playd cover embed-youtube-play" type="button" aria-label="Open"></button>
				</div>
			</div>
		</div>
		<div class="curtain remove">
			<div class="ratio-keeper">
				<div class="video-five"></div>
				<div class="wrap embed-youtube">
					<div class="video embed-youtube" data-id="djV11Xbc914">
					</div>
					<button class="playe cover embed-youtube-play" type="button" aria-label="Open"></button>
				</div>
			</div>
		</div>
		<div class="curtain remove">
			<div class="ratio-keeper">
				<div class="video-six"></div>
				<div...

CSS

html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

body {
  background: #302b63;
}

.container2 .container {
  background: teal;
}

.container3 .container {
  background: green;
}

.container1 {
  position: absolute;
  left: 0;
  right: 0;
  min-height: 100%;
  min-width: 255px;
  display: flex;
  padding: 8px 8px;
}

.curtain1 {
  flex: 1 0 0;
  margin: auto;
  max-width: 640px;
  border: 21px solid;
  border-radius: 12px;
  border-color: #000 #101010 #000 #101010;
  position: relative;
}

.ratio-keeper {
  position: relative;
  height: 0;
  padding-top: 56.25%;
  margin: auto;
  overflow: hidden;
}

.container {
  position: absolute;
  left: 0;
  right: 0;
  min-height: 100%;
  padding: 8px 8px;
}

.curtain {
  margin: auto auto 40px;
  max-width: 640px;
  border: 21px solid;
  border-radius: 12px;
  border-color: #000 #101010 #000 #101010;
  position: relative;
}

.embed-youtube iframe,
.embed-youtube .embed-youtube-play,
.embed-youtube .embed-youtube-play::before {
  position: absolute;
}

.embed-youtube iframe {
  height: 100%;
  width: 100%;
  top: 0;
  left: 0;
}

.embed-youtube .embed-youtube-play {
  -webkit-appearance: none;
  appearance: none;
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  margin: auto;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 90px;
  height: 90px;
  border-radius: 50%;
  cursor: pointer;
  border: 9px solid blue;
  background: transparent;
  filter: drop-shadow(3px 3px 3px #000000b3);
  z-index: 1;
}

.embed-youtube-play::before {
  content: "";
  width: 0;
  height: 0;
  border-top: 20px solid transparent;
  border-bottom: 20px solid transparent;
  border-left: 27px solid blue;
  transform: translateX(4px);
}

.embed-youtube-play:hover {
  box-shadow: 0 0 0 5px rgba(43, 179, 20, 0.5);
}

.embed-youtube-play:focus {
  outline: 0;
  box-shadow: 0 0 0 5px rgba(0, 255, 255, 0.5);
}

.embed-youtube.active .embed-youtube-play {
  display: none;
}

@keyframes rotate {
  0% {
...

JavaScript

const manageCover = (function makeManageCover() {

  function showCover(playButton) {
    const cover = playButton.parentElement;
    cover.classList.add("active");
  }

  function openCurtain(curtain) {
    curtain.classList.add("slide");
  }

  function coverClickHandler(evt) {
    const cover = evt.currentTarget;
    showCover(cover);
    const curtain = evt.currentTarget.parentElement.parentElement.parentElement;
    openCurtain(curtain);
  }

  function addCoverHandler(coverSelector, handler) {
    const cover = document.querySelector(coverSelector);
    cover.addEventListener("click", handler);
  }

  function addClickToButtons(playButtons) {
    playButtons.forEach(function playButtonHandler(playButton) {
      playButton.addEventListener("click", coverClickHandler);
    });
  }

  function init( /*selectors*/) {
    //config.containers = document.querySelector(selectors.container);
    // const allContainers = document.querySelector(".container");
    //const playButtons = document.querySelector(selectors.playButton);
    const allPlaybuttons = document.querySelectorAll(".cover");
    //const allPlaybuttons = document.querySelectorAll(".embed-youtube-play");
    addClickToButtons(allPlaybuttons);
  }


  return {
    addCoverHandler,
    init
  };
}());

const manageUI = (function makeManageUI() {
  document.body.scrollTop = 0;
  const players = [];

  function findPlayers() {
    const allCovers = document.querySelectorAll(".cover");
    const allWrappers = document.querySelectorAll(".wrap");
    allCovers.forEach(function addToPlayers(cover, index) {
      players.push({
        "cover": cover,
        "wrapper": allWrappers[index]
      });
    });
  }

  // inline arrow function, direct return
  function getWrapper(cover) {
    const index = players.findIndex(
      (player) => player.cover === cover
    );
    return players[index].wrapper;
  }

  function exitClickHandler() {
    window.scrollTo(0, 0);
  }

  function addClickToExit(exitButtons) {
 ...