formspree-demo.html

<div>
  <style>
    .contact-form__btn {
      background-color: #207786;
      border: none;
      color: white;
      padding: 15px 32px;
      text-align: center;
      text-decoration: none;
      display: inline-block;
      font-size: 16px;
      margin-top: 10px;
    }
  </style>
</div>
<form
  class="contact-form"
  action="https://formspree.io/example@example.tld"
  method="POST"
>
  <div>
    <div>
      <h3>
        <label for="first_name">First</label>
      </h3>
      <input type="text" name="first_name" />
    </div>
    <div>
      <h3>
        <label for="last_name">Last</label>
      </h3>
      <input type="text" name="last_name" />
    </div>
  </div>
  <div>
    <h3>
      <label for="_replyto">Email</label>
    </h3>
    <input type="email" name="_replyto" />
  </div>
  <div>
    <h3>
      <label for="phone">Phone</label>
    </h3>
    <input type="tel" name="phone" />
  </div>
  <div>
    <h3>
      <label for="comments"></label>
    </h3>
    <textarea name="comments" rows="10"></textarea>
  </div>
  <input class="contact-form__btn" type="submit" value="Send" />
</form>