DIV弹窗层 链接弹出

<div class="centerit"   id="divjianjie" style="display:none; z-index:9999";">
  <div class="chat-container">
    <aside> 
      <div class="top-bar">
        <div class="menu-burger-container">
          <div class="menu-burger"></div>
        </div>
        <div class="new-conversation">公告</div>
      </div>
      <div class="conversations">
        <div class="thread">
          <div class="details">
             
            
            <div class="last-message">1.公告公告公告公告公告公告公告公告</div>
          </div>
         
        </div>
        <div class="thread active">
          <div class="details">
            
         
            <div class="last-message">2.公告公告公告公告公告公告公告公告</div>
          </div>
         
        </div>
        <div class="thread">
          <div class="details">
           
           
            <div class="last-message">3.公告公告公告公告公告公告公告公告</div>
          </div>
        
        </div>

  <div class="thread active">
          <div class="details">
            
         
            <div class="last-message">4.公告公告公告公告公告公告公告公告</div>
          </div>
         
        </div>

      </div>

    </aside>
    <main>
      <div class="top-bar">
       <div class="user-info"></div>
        <div class="buttons">
          <div class="call">
           <a  onclick="javascript:location.reload()"><div class="new-conversation">关闭</div></a>
          </div>
        </div>
      </div>
      <div class="messages" id="messages">
       
            <iframe  scrolling="no" name="jianjie" src="" style="border:0px solid black; width:100%; height:100%; z-index:9999";></iframe>

       
      </div>
      
    </main>
  </div>
</div>
<div>
</div>







<style>
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: sans-serif;
}

body {
  
  width: 100vw;
  height: 100vh;
}

.centerit {
  position:fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.chat-container {
  background-color: #f4f4f4;
  width:800px;
  height: 670px;
  border-radius: 10px;
  overflow: hidden;
  display: flex;
}
.chat-container .top-bar {
  width: 100%;
  height: 80px;
  display: flex;
}
.chat-container aside {
  width: 275px;
  height: 100%;
  background-color: #363e47;
  display: flex;
  flex-direction: column;
}
.chat-container aside .top-bar {
  background-color: #444444;
  justify-content: space-between;
}
.chat-container aside .menu-burger-container {
  margin: 20px;
  height: 40px;
  width: 40px;
  cursor: pointer;
}
.chat-container aside .menu-burger-container:hover > .menu-burger, .chat-container aside .menu-burger-container:hover > .menu-burger:before, .chat-container aside .menu-burger-container:hover > .menu-burger:after {
  animation-name: menuHover;
}
.chat-container aside .menu-burger-container .menu-burger {
  height: 2px;
  width: 10px;
  background-color: #fff;
  top: 20px;
  left: 10px;
  position: relative;
}
.chat-container aside .menu-burger-container .menu-burger, .chat-container aside .menu-burger-container .menu-burger:before, .chat-container aside .menu-burger-container .menu-burger:after {
  animation-duration: 1s;
  animation-iteration-count: infinite;
}
.chat-container aside .menu-burger-container .menu-burger:before, .chat-container aside .menu-burger-container .menu-burger:after {
  content: '';
  height: 2px;
  width: 16px;
  background-color: #fff;
  display: block;
  position: relative;
}
.chat-container aside .menu-burger-container .menu-burger:before {
  top: -6px;
  animation-delay: 500ms;
}
.chat-container aside .menu-burger-container .menu-burger:after {
  top: 4px;
  animation-delay: 250ms;
}
.chat-container aside .new-conversation {
  height: 42px;
  padding: 0 20px;
  background-color: #01e777;
  border-radius: 25px;
  color: #ffffff;
  text-align: center;
  margin: 19px 30px;
  cursor: pointer;
  line-height: 42px;
  box-sizing: content-box;
  border: solid #01e777 0px;
  transition: all 200ms ease-in-out;
  font-size: 15px;
}
.chat-container aside .new-conversation:hover {
  transition: all 70ms ease-in-out;
  transform: translate(2px, -2px);
  border: solid #01e777 2px;
}
.chat-container aside .conversations {
  height: calc(100% - 80px);
  width: 100%;
}
.chat-container aside .conversations .thread {
  display: flex;
  justify-content: space-between;
  margin-bottom: 8px;
  cursor: pointer;
}
.chat-container aside .conversations .thread.active {
  background-color: #3f4953;
}
.chat-container aside .conversations .thread:hover {
  background-color: #3f4953;
}
.chat-container aside .conversations .thread .details {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-rows: 1fr 1fr;
  grid-template-areas: "user-image user-name" "user-image last-message";
  margin: 17px;
  align-items: center;
}
 
.chat-container aside .conversations .thread .details .user-name, .chat-container aside .conversations .thread .details .last-message {
  width: 260px;
}
 
.chat-container aside .conversations .thread .details .last-message {
  grid-area: last-message;
  color: #626c76;
  font-size: 12px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.chat-container main {
  width: calc(100% - 275px);
  height: 100%;
  display: flex;
  flex-direction: column;
}
.chat-container main .top-bar {
  background-color: #f1f1f1;
  border-bottom: solid 1px #d6d6d6;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0px 40px;
}
 
.chat-container main .top-bar .call{float:right; cursor: pointer;font-size:34px;}
 
 
.chat-container main .messages {
  height: calc(100% - 80px);
  display: flex;
  flex-direction: column;
/*  overflow-y: scroll;*/
}
 

@keyframes menuHover {
  0% {
    width: 10px;
  }
  50% {
    width: 16px;
  }
  100% {
    width: 10px;
  }
}


</style>

<li class="layui-nav-item" runat="server"  id="logo">
<a href="你要弹出的链接" target="jianjie" onclick="document.getElementById('divjianjie').style.display='block'"> 登录/注册 弹出</a>
</li>