<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="Generator" content="EditPlus®">
<meta name="Author" content="Mu Renzi Wei Yichen">
<title>Modify the style of the input attribute placeholder</title>
<style>
#canChange::-webkit-input-placeholder{
color:red;
font-size:2em;
}
</style>
</head>
<body>
<input type="text" placeholder="I can change">
<input type="text" placeholder="I can change" id="canChange">
</body>
</html>
Whether the browser supports it, adding a prefix is, for example, webkit is a browser with webkit kernel, ms is a browser with ms kernel