小编Adr*_*ian的帖子

.form-control {
    width: 600px;
    fill: none;
    background: transparent;
    border: none;
    border-bottom: 1px solid grey;
    font-size: 18px;
    margin-bottom: 16px;
}

<form id="contactForm" method="POST" action="">
  <input name="fName" type="text" class="form-control" placeholder="What should I call you? Person X?" required>
  <br>
  <input name="email" type="email" class="form-control" placeholder="Only, if you want to be emailed back">
  <br>
</form>