index.html

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

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .editor {
            height: 100px;
        }

        .edit-panel {
            position: relative;
            width: 100%;
            height: auto;
            font-size: 14px;
            line-height: 20px;
            border: 1px solid;
        }

        .show-placeholder::before {
            content: attr(placeholder);
            position: absolute;
            top: 4px;
            left: 8px;
            color: #555;
            pointer-events: none;
        }
    </style>
</head>

<body>
    <div class="parent">
        <form>
            <input type="text">
        </form>
    </div>
    <style>
        .parent:hover input {
            background: green;
        }

        .parent:hover form {
            background: orange;
        }
    </style>
</body>

</html>