jquery 层居中

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>jQuery Centered Layer</title>
    <style>
        .container {
            position: relative;
            height: 100vh;
        }
        .centered-layer {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            width: 200px;
            height: 200px;
            background-color: #f0f0f0;
            text-align: center;
            line-height: 200px;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="centered-layer">Centered Layer</div>
    </div>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>jQuery Centered Layer</title>
    <style>
        .container {
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
        }
        .centered-layer {
            width: 200px;
            height: 200px;
            background-color: #f0f0f0;
            text-align: center;
            line-height: 200px;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="centered-layer">Centered Layer</div>
    </div>
</body>
</html>