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    <meta charset="UTF-8">
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    <title>gradient 1_bit CSS 动效实战课程之渐变色操作</title>
    <style>
        body {
            margin: 0 0;
            text-align: center;
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        span {
            display: inline-block;
            margin-top: 300px;
            font-size: 50px;
            color: aliceblue;
            font-weight: bold;
        }
        
        .float-gradient {
            background: linear-gradient(-45deg, #990066, #FFCC00, #CC0033);
            background-size: 500% 500%;
            animation: moiveAnimation 15s infinite;
        }
        
        @keyframes moiveAnimation {
            0% {
                background-position: 0% 50%
            }
            50% {
                background-position: 100% 50%
            }
            100% {
                background-position: 0% 50%
            }
        }
    </style>
</head>

<body class="float-gradient">
    <span>
        纯 CSS 浮动背景——1_bit CSS动效实战课程
    </span>
</body>

</html>

转载：
01超精美渐变色动态背景完整示例【CSS动效实战（纯CSS与JS动效）】_css好看的渐变色_1_bit的博客-CSDN博客
https://blog.csdn.net/A757291228/article/details/124611342