You can try to run the following code to change the color of the alert box. To change the color of the alert box, use the following custom alert box. We’re using JavaScript library, jQuery to achieve this and will change the color of the alert box to “blue” −
Example
<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js">
</script>
<script>
function functionAlert(msg, myYes) {
var confirmBox = $("#confirm");
confirmBox.find(".message").text(msg);
confirmBox.find(".yes").unbind().click(function() {
confirmBox.hide();
});
confirmBox.find(".yes").click(myYes);
confirmBox.show();
}
</script>
<style>
#confirm {
display: none;
background-color: #8416f9;
color: #FCD116;
border: 1px solid #aaa;
position: fixed;
width: 250px;
left: 50%;
margin-left: -100px;
padding: 6px 8px 8px;
box-sizing: border-box;
text-align: center;
}
#confirm button {
background-color: #48E5DA;
display: inline-block;
border-radius: 5px;
border: 1px solid #aaa;
padding: 5px;
text-align: center;
width: 80px;
cursor: pointer;
}
#confirm .message {
text-align: left;
}
</style>
</head>
<body>
<div id="confirm">
<div class="message">This is a warning message.</div>
<button class="yes">OK</button>
</div>
<input type="button" value="Click Me" onclick="functionAlert();" />
</body>
</html>