html5自定义video标签的海报与播放按钮功能

.yourDiv{
 background-color: black;
 height:20em;
 background-image: url('./images/timg.jpg');
 background-size: contain;
 background-repeat: no-repeat;
 background-position: center;
}

<div class="yourDiv"></div>

.yourDiv {
 background-color: black;
 height:20em;
 background-image: url('./images/timg.jpg');
 background-size: contain;
 background-repeat: no-repeat;
 background-position: center;
 
 display:flex;
 align-items: center;
}
.yourDiv img { 
 width:20%;
 margin-left: 40%;
}

<div class="yourDiv">
 <img src="./images/play.png">
</div>

.yourDiv {
 background-color: black;
 height:20em;
 background-image: url('./images/timg.jpg');
 background-size: contain;
 background-repeat: no-repeat;
 background-position: center;
 
 display:flex;
 align-items: center;
 
 position: absolute;
 top: 0px;
 left: 0px;
 width: 100%;
}
.yourDiv img { 
 width:20%;
 margin-left: 40%;
}

.father {
 background-color: black;
 width:100%;
 height:16em;
 position: relative;
}

  <div class="father">
  <video id="video" controls="controls" autoplay="autoplay" style="width:100%;height:16em">
   <source src="./videos/v1.mp4" type="video/ogg" />
   <source src="./videos/v1.mp4" type="video/mp4" />
  </video>

  <div class="yourDiv">
   <img src="./images/play.png">
  </div>
 </div>

 <div class="father">
  <video id="video" controls="controls" autoplay="autoplay" style="width:100%;height:16em">
   <source src="./videos/v1.mp4" type="video/ogg" />
   <source src="./videos/v1.mp4" type="video/mp4" />
  </video>

  <div id="poster" class="yourDiv" onclick="play()">
   <img src="./images/play.png">
  </div>
 </div>

var video = document.getElementById("video");

function play(){
 document.getElementById("poster").style.display = "none";
 video.play();
}