css鼠标进入

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CSS Mouse Enter Example</title>
    <style>
        .button {
            padding: 10px 20px;
            background-color: #4CAF50;
            color: white;
            border: none;
            cursor: pointer;
            transition: background-color 0.3s ease;
        }

        .button:hover {
            background-color: #45a049;
        }
    </style>
</head>
<body>
    <button class="button">Hover Me</button>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>JavaScript Mouse Enter Example</title>
    <style>
        .box {
            width: 200px;
            height: 200px;
            background-color: #f1f1f1;
            display: flex;
            justify-content: center;
            align-items: center;
            transition: background-color 0.3s ease;
        }

        .box:hover {
            background-color: #ddd;
        }
    </style>
</head>
<body>
    <div class="box" onmouseover="changeText()" id="box">Hover Me</div>

    <script>
        function changeText() {
            document.getElementById('box').innerHTML = 'Hello, World!';
        }
    </script>
</body>
</html>