<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>&lt;input type="hidden"&gt; 示例</title>
  <style>
    html {
      font-family: sans-serif;
    }

    form {
      width: 500px;
    }

    div {
      display: flex;
      margin-bottom: 10px;
    }

    label {
      flex: 2;
      line-height: 2;
      text-align: right;
      padding-right: 20px;
    }

    input, textarea {
      flex: 7;
      font-family: sans-serif;
      font-size: 1.1rem;
      padding: 5px;
    }

    textarea {
      height: 60px;
    }

  </style>
</head>

<body>
  <form>
    <div>
      <label for="title">文章标题：</label>
      <input type="text" id="title" name="title" value="精彩博文">
    </div>
    <div>
      <label for="content">文章内容：</label>
      <textarea id="content" name="content">
精彩博文，尽请欣赏！
      </textarea>
    </div>
    <div>
      <button type="submit">上传文章</button>
    </div>
    <input type="hidden" id="postId" name="postId" value="34657">
  </form>
</body>
</html>