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<html>
<head>
<style>
 

</style>
</head>
<body>
<h4> 신발 사이즈 선택</h4>
<select name="size" >
<optgroup label="female">
  <option value="225">225mm</option>
  <option value="230" >230mm</option>
  <option value="235">235mm</option>
 </optgroup>
<optgroup label="male">
  <option value="255">255mm</option>
  <option value="260" >260mm</option>
  <option value="265">265mm</option>
 </optgroup>
</select> 


</body>
</html>