suggestion.html

 <!-- iframe content-->
 <!DOCTYPE html>
 <html lang="en">

 <head>
     <meta charset="UTF-8">
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <link rel="stylesheet" href="css/mycss.css">
     <link rel="stylesheet" href="css/iframe.css">
 </head>

 <body>
     <div class="container center alignCenter">
         <form action="#" method="GET">
             <h1>Questionnaire</h1>
             <p>pls leave your profile</p>
             <p>phone:<input type="tel" name="phone" placeholder="ex.0938-111-111"></p>
             <p>email:<input type="email" name="email"></p>
             <p>請輸入竟見</p>
             <p><textarea name="content" cols="30" rows="10"></textarea></p>
             <p><input type="submit" value="confirm"><input type="reset" value="rest"></p>
         </form>
     </div>
 </body>

 </html>