<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script src="jquery-3.2.1.js"></script>
<style>
#div1{
height: 400px;
width: 600px
background-color: #7b7b7b;
opacity: 1;
}
</style>
</head>
<body>
<div id="div1"></div>
<script>
(function ($) {
$.fn.extend({
hello:function () {
setTimeout("$(\"#div1\").css(\"background-color\",\"red\");",2000);
setTimeout("$(\"#div1\").css(\"background-color\",\"black\");",4000);
setTimeout("$(\"#div1\").css(\"background-color\",\"gold\");",6000);
}
})
})(jQuery);
$("#div1").hello()
</script>
</body>
</html>
