How to save a javascrip event in the browser? : This pop-up window. After the client visited the site in 30 seconds, a window will automatically appear. After closing the window disappears. But when the client goes to another page, the script starts to work ( after refreshing the page). How to remember closing the modal window at the time of visiting the client's site?

    <div id="parent_popup">
    			<div id="popup">
    				message message message message message message message 
    				<a class="close"title="close" onclick="document.getElementById('parent_popup').style.display='none';">X</a>
    			</div>
    		</div>
     #parent_popup{
     	 padding: 20px;
        background-color: rgba(0, 0, 0, 0.8);
        display: none;
        position: fixed;
        z-index: 99999;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;
    }
    #popup{
        background: #fff;
        max-width: 520px;
        margin: 10% auto;
        padding: 5px 20px 13px 20px;
        border: 10px solid #ddd;
        position: relative;
        -webkit-box-shadow: 0px 0px 20px #000;
        -moz-box-shadow: 0px 0px 20px #000;
        box-shadow: 0px 0px 20px #000;
        -webkit-border-radius: 15px;
        -moz-border-radius: 15px;
         border-radius: 15px;
    }
    .close{
        background-color: rgba(0, 0, 0, 0.8);
        border: 2px solid #ccc;
        height: 24px;
        line-height: 24px;
        position: absolute;
        right: -24px;
        cursor: pointer;
        font-weight: bold;
        text-align: center;
        text-decoration: none;
        color: rgba(255, 255, 255, 0.9);
        font-size: 14px;
        text-shadow: 0 -1px rgba(0, 0, 0, 0.9);
        top: -24px;
        width: 24px;
        -webkit-border-radius: 15px;
        -moz-border-radius: 15px;
        -ms-border-radius: 15px;
        -o-border-radius: 15px;
        border-radius: 15px;
        -moz-box-shadow: 1px 1px 3px #000;
        -webkit-box-shadow: 1px 1px 3px #000;
         box-shadow: 1px 1px 3px #000;
    }
    .close:hover{
        background-color: rgba(0, 122, 200, 0.8);
    }
    
    <script type="text/javascript">
    			var delay_popup = 5000;setTimeout("document.getElementById('parent_popup').style.display='block'", delay_popup);
    			
    </script>

