JSFiddle - React, Tailwind, and code Playground

HTML

<div class="card">
       <h1>Contact</h1>
       <p>Fill in this form and send to me. Comments, questions and suggestions. I will answer you as soon as possible as this work is done on spare time.</p>
       <form action="contactme" method="post">

         <input type="hidden" name="type" value="contact">
         <div class="rowbox">
           <label>Name</label>
           <input type="text" name="name" required>
         </div>

         <div class="rowbox">
           <label>Mail</label>
           <input type="email" name="mail" required>
         </div>

         <div class="rowbox">
           <label>Subject</label>
           <input type="text" name="subject" required>
         </div>

         <div class="rowboxbig">
           <label>Message</label>
           <textarea name="msg" required></textarea>
         </div>

         <div class="rowbox">
           <label for="submit">Send</label>
           <input id="submit" type="submit" value="submit">
         </div>

       </form>
     </div>

CSS

.card {
  display: block;
  width: 90%;
  background: #fff;
  border-radius: 6px;
  box-shadow: 0 7px 14px 0 rgba(60, 66, 87, 0.1), 0 3px 6px 0 rgba(0, 0, 0, 0.1);
  position: relative;
  padding: 25px;
  margin-bottom: 15px;
}

.rowbox {
  display: flex;
  flex-direction: row;
  height: 56px;
  justify-content: flex-end;
  text-align: center;
  margin-top: 8px;
}

.rowboxbig {
  display: flex;
  height: auto;
  flex-direction: row;
  padding-bottom: 5px;
  margin-top: 8px;
}

input {
  font-size: 16px;
  height: 40px;
  width: 100%;
  align-self: center;
  padding: 5px 15px 10px 15px;
  font-weight: 300;
  border: 0;
  background-color: #f2f2f2;
  border-radius: 5px;
}

textarea {
  resize: vertical;
  font-size: 16px;
  height: 200px;
  width: 100%;
  align-self: center;
  padding: 5px 15px 10px 15px;
  font-weight: 300;
  border: 0;
  background-color: #f2f2f2;
  border-radius: 5px;
}

label {
  display: inherit;
  width: 100px;
  font-size: 18px;
  font-weight: 300;
  justify-content: flex-end;
  padding-right: 10px;
  margin-top: 3px;
}

label[for='submit'] {
  margin-top: 3px;
  padding: 0;
  height: 48px;
  font-size: 18px;
  border: none;
  font-weight: 300;
  border-radius: 4px;
  background-color: #45a049;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
}

@media screen and (max-width: 600px) {

  .rowbox,
  .rowboxbig,
  input[type=submit] {
    flex-direction: column;
    height: auto;
    width: 100%;
    text-align: center;
  }


  label {
    display: inherit;
    width: auto;
    height: 20px;
    align-items: center;
    justify-content: flex-start;
    padding-top: 0px;
    margin-bottom: 5px;
  }
}


input[type=submit] {
  display: none;
}