How to make Sticky ad or sticky div with close button?

How to make Sticky ad or sticky div with close button?

HTML Code

 <div id="T4Tutorials_UP1" class="T4Tutorials">
    	<div class="T4Tutorials_UP" >
    		<h2>Welcome</h2>
    		<a class="Exit" href="#T4Tutorials_UP1">×</a>
    		<div class="Main_Main_Content">
    			This is the div showing the Main_Content
    		</div>
    	</div>
    </div>

CSS Code

  .T4Tutorials {
    position: fixed;
    bottom: 0;
    height: 90px;
    left: 0;
    right: 0;
    background: red;
    transition: opacity 500ms;
    visibility: visible;
    opacity: 1;
}
          .T4Tutorials:target {
            visibility: hidden;
            opacity: 0;
            display:none
          }
          .T4Tutorials_UP {
    margin: 5px auto;
    padding: 0px;
    background: #fff;
    border-radius: 5px;
    width: 80%;
    position: relative;
}
          .T4Tutorials_UP h2 {
            margin-top: 0;
            color: green;
            font-family: Tahoma, Arial, sans-serif;
          }
          .T4Tutorials_UP .Exit {
    position: absolute;
    top: -40px;
    right: 0px;
    font-size: 30px;
    font-weight: bold;
    text-decoration: none;
    color: blue;
    background-color: chartreuse;
}
          .T4Tutorials_UP .Exit:hover {
            color: orange;
          }
          .T4Tutorials_UP .Main_Content {
            max-height: 30%;
            overflow: auto;
          }

Download Code

sticky ad with close button