<form action="https://cs12.net/form/submit.php" method="post">
   <fieldset>
     <legend>Date and Time     </legend>
     <p>Date
     </p>
     <p>
       <input type="date" name="my_date"/>

     </p>
     <p>Datetime-local
     </p>
     <p>
       <input type="datetime-local" name="my_datetime"/>

     </p>
     <p>Time
     </p>
     <p>15 minute steps:
       <input type="time" name="my_time_15" step="900" value="12:00"/>

     </p>
     <p>1 minute steps:
       <input type="time" name="my_time_1" step="60" value="12:00"/>

     </p>
     <p>1 second steps:
       <input type="time" name="my_time_1s" step="1" value="12:00"/>

     </p>   </fieldset>
   <p>
     <button type="submit">Submit     </button>
   </p>
 </form>