前端实现界面切换主题代码示例

/* default.css */
body {
    background-color: white;
}

/* dark.css */
body {
    background-color: black;
}

/* light.css */
body {
    background-color: lightcyan;
}

<!DOCTYPE html>
<html lang="en" class="dark">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>主题切换方案一</title>
    <link type="text/css" href="css/default.css" rel="external nofollow"  rel="stylesheet" title="default">
    <link type="text/css" href="css/dark.css" rel="external nofollow"  rel="stylesheet alternate" title="dark">
    <link type="text/css" href="css/light.css" rel="external nofollow"  rel="stylesheet alternate" title="light">
</head>

<body>
    <select name="主题" onchange="changeTheme(this.value)">
        <option value="default">默认</option>
        <option value="dark">夜晚</option>
        <option value="light">白天</option>
    </select>
</body>

<script src="static/js/jquery.min.js"></script>
<script>
    function changeTheme(theme) {
        $('link').attr('disabled', true)
        $(`link[title=${theme}]`).attr('disabled', false)
    }
</script>

</html>

<!DOCTYPE html>
<html lang="en" class="dark">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>主题切换方案二</title>
    <style>
        :root {
            --theme-color: #333333;
        }

        html {
            background-color: var(--theme-color, "#E65A65");
        }
    </style>
</head>

<body>
    <select name="主题" onchange="changeTheme(this.value)">
        <option value="#333333">默认</option>
        <option value="#1a7efc">蓝色</option>
        <option value="#16d46b">绿色</option>
        <option value="#f1ce6b">黄色</option>
    </select>
</body>

<script>
    function changeTheme(theme) {
        document.documentElement.style.setProperty('--theme-color', theme)
    }
</script>

</html>