需求：在1秒内，由一个颜色变到另一个颜色，不是1秒后再变色。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>背景渐变</title>
<style>
div {
200px;
height: 200px;
background-color: red;
color: white;
font-size: 50px;
font-weight: 500;
}
p {
20px;
height: 20px;
background-color: deepskyblue;
}
</style>
</head>
<body>
<p></p>
<div>123</div>
</body>
<script src="https://libs.baidu.com/jquery/2.1.4/jquery.min.js"></script>
<!-- 变态：要想使用颜色渐变，必须要用这个插件！ -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-color/2.1.2/jquery.color.min.js"></script>
<script>
$(function () {
$("p").click(() => {
$("div").animate({
100,
height: 100,
backgroundColor: "blue",
},1000);
})
});
</script>
</html>