JSFiddle - React, Tailwind, and code Playground

HTML

<script>
	
function myFunction(x) {
    var popup = document.querySelectorAll('.popup')[0];
    if(x == 'show'){
    	popup.style.display = 'block';
    	setTimeout(()=> {
    		popup.style.opacity = 1;
    	},50);
    }
    if(x == 'close'){
    	popup.style.opacity = 0,
    	setTimeout(()=> {
    		popup.style.display = 'none';
    	},700);
    }
}

</script>

<div onclick="myFunction('show')">Click me!</div>
<div class="popup">
    <table class="popuptext" id="myPopup" border='1'>
    <div id="close" onclick="myFunction('close')">X</div>
    <tr>
        <th>Номер телефона</th>
        <th>Имя</th>
        <th>Заказ</th>
        <th>Дата поступления заказа</th>
        <th>Примечание</th>
    </tr>
    <tr>
        <td><input type="text" value="p_nr" id="p_nr" name="p_nr" /></td>
        <td><input type="text" value="p_name" id="p_name" name="p_name" /></td>
        <td><input type="text" value="p_product" id="p_product" name="p_product" /></td>
        <td><input type="text" value="p_stadate" id="p_stadate" name="p_stadate" /></td>
        <td><input type="text" value="p_comment" id="p_comment" name="p_comment" /></td>
    </tr>
</div>

CSS

/* Popup container */
.popup {
    /* display: none; */
    opacity:  0;
    position: relative;
    cursor: pointer;
    transition: 0.7s;
}
 
/* The actual popup (appears on top) */
.popup .popuptext {
    transition: 0.7s;
    /* opacity:  0; */
    width: 160px;
    background-color: #555;
    color: #fff;
    text-align: center;
    border-radius: 6px;
    padding: 40px 10px 10px 10px;
    position: absolute;
    z-index: 1;
    /* bottom: 125%; */
    left: 0%;
    margin-top: 50px;
}
 
/* Popup arrow */
.popup .popuptext::after {
    content: "";
    position: absolute;
    top: 100%;
    left: 50%;
    margin-left: -5px;
    border-width: 5px;
    border-style: solid;
    border-color: #555 transparent transparent transparent;
}
 
/* Toggle this class when clicking on the popup container (hide and show the popup) */
.popup .show {
    visibility: visible;
    -webkit-animation: fadeIn 1s;
    animation: fadeIn 1s;
}
 
/* Add animation (fade in the popup) */
@-webkit-keyframes fadeIn {
    from {opacity: 0;}
    to {opacity: 1;}
}
 
@keyframes fadeIn {
    from {opacity: 0;}
    to {opacity:1 ;}
}

#close{
	width: 35px;
	height: 30px;
	/* background-color:  #000; */
	color:  #fff;
	text-align:  center;
	line-height:  30px;
	position:  relative;
	z-index:  2;
	left: 878px;
	top: 88px;
	border-radius: 5px;
	border: 1px solid;
}

#close:hover{
	background-color:  #000; 
}