联系表单中的文本动画 - HTML/CSS

Question

我有以下代码：

/* Contact Form */

input[type=text],
[type=email],
select,
textarea {
  width: 100%;
  padding: 12px;
  border: 1px solid #555;
  margin-top: 6px;
  margin-bottom: 16px;
  resize: vertical;
}

input[type=submit] {
  background-color: #0563bb;
  color: white;
  padding: 12px 20px;
  border: none;
  cursor: pointer;
}

input[type="text"]:focus,
input[type="email"]:focus,
#subject:focus {
  background: var(--bgFormElsFocus);
  transform: scale(1.02);
  transition: transform 0.2s ease-in-out;
}

input[type=submit]:hover {
  opacity: 0.9;
}

.contactform {
  position: relative;
  border-radius: 50px;
  background-color: #f2f2f2;
  padding: 5px;
  z-index: 2;
  display: block;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: auto;
  margin-top: 1%;
  width: 100%;
  animation-name: gradient;
  animation-duration: 3s;
  animation-iteration-count: infinite;
}

.contactform:hover {
  animation-name: gradient;
  animation-duration: 15s;
  animation-iteration-count: infinite;
}

.column {
  float: center;
  width: 50%;
  margin-top: 6px;
  padding: 20px;
  display: block;
  margin-left: auto;
  margin-right: auto;
}

.row:after {
  content: "";
  display: table;
  clear: both;
}

@media screen and (max-width: 600px) {
  .column,
  input[type=submit] {
    width: auto;
    margin-top: 0;
  }
}

.shakingErr {
  border-color: red;
  animation: shake 0.82s forwards;
}

@keyframes shake {
  10%,
  90% {
    transform: translate3d(-1px, 0, 0);
  }
  20%,
  80% {
    transform: translate3d(2px, 0, 0);
  }
  30%,
  50%,
  70% {
    transform: translate3d(-4px, 0, 0);
  }
  40%,
  60% {
    transform: translate3d(4px, 0, 0);
  }
}

<section id="contact">
  <div class="container" data-aos="fade-up">
    <div class="contactform">
      <div style="text-align:center">
        <div class="section-title">
          <h2><br/>Get In Touch</h2>
        </div>
        <p>Feel Free To Reach Out To Me Through This Form! </p>
      </div>
      <div class="row">
        <div class="column">
          <form name="myform" action="https://formspree.io/f/xr123gjbqpq" id="my-form" method="POST" novalidate>
            <label for="firstname">First Name</label>
            <input type="text" id="first name" name="firstname" placeholder="Your First Name.." required>
            <label for="lastname">Last Name</label>
            <input type="text" id="lastname" name="lastname" placeholder="Your Last Name.." required>
            <label for="email">Email:</label>
            <input type="email" id="email" name="email" placeholder="Your Email.." required>
            <label for="subject">Subject</label>
            <textarea id="subject" name="subject" placeholder="Lets Collaborate.." style="height:170px" required></textarea>
            <input type="submit" value="Submit">
          </form>
        </div>
      </div>
    </div>
  </div>
</section>

我想在输入字段上显示文本动画。例如，我希望我的预期输出是这样的：

https://watch.screencastify.com/v/3mlMie2rx0UzhdymHYCR

如您所见，我希望诸如“名字”之类的文本位于输入字段内，并且当用户单击输入字段时，文本应具有动画效果并位于顶部。我怎样才能完成这项任务？有什么建议吗？

Answer 1

如何做到这一点有很多变种，其中一种是使用extra-div进行输入和标签，浮动文本的作用将由标签发挥：

.wrapper {
  padding: 20px;
}

.input-data {
  height: 40px;
  width: 100%;
  position: relative;
}

.input-data input {
  height: 100%;
  width: 100%;
  border: none;
  font-size: 17px;
  border-bottom: 2px solid silver;
  transition: border-color .4s;
  outline: none;
}

.input-data input:focus~label,
.input-data input:valid~label {
  transform: translateY(-20px);
  font-size: 13px;
  color: #4158d0;
}

.input-data label {
  position: absolute;
  bottom: 10px;
  left: 0;
  color: grey;
  pointer-events: none;
  transition: all 0.3s ease;
}

.input-data input:focus,
.input-data input:valid {
  border-color: #4158d0;
}

<div class="wrapper">
  <div class="input-data">
    <input type="text" required>
    <label>Name</label>
  </div>
</div>

Answer 2

我尝试为您创建一个测试版，使用您链接的视频作为参考

仅使用 HTML 和 CSS...

这里的诀窍是创建一个 Extra Div 作为父级，因此我们可以将标签和输入放入其中。

现在将父级设置为position: relative;，因此标签将为absolute

现在我们可以成功地使用 TOP、LEFT、RIGHT、BOTTOM 了（将标签定位为占位符）

逻辑

我把逻辑放在这里.input-container input:focus~label

确保标签在 HTML 中的输入之后，并且在父级内部

删除焦点边框

请记住，如果输入焦点，它会自动像边框一样...

要删除此边框，请使用outline: none;，因为该边框不能使用border: none;删除

---

就是这样，测试我为你写的代码！我希望这会有所帮助

这里是代码

* {
  --input-height: 3rem;
  --light-black: rgba(0, 0, 0, 0.3);
  --medium-black: rgba(0, 0, 0, 0.6);
}

section {
  height: 100vh;
  width: 100vw;
  display: grid;
  place-content: center;
}

.input-container input {
  height: var(--input-height);
  width: 80vw;
  font-size: 2rem;
  border: none;
  border-bottom: 2px solid var(--light-black);
}

.input-container {
  position: relative;
  display: grid;
  place-items: center start;
}

.input-container label {
  position: absolute;
  left: 1rem;
  font-size: 1.5rem;
  color: var(--medium-black);
  transition-duration: 0.5s;
}

.input-container input:focus~label {
  position: absolute;
  font-size: 1rem;
  top: -1rem;
  left: 0;
  transition-duration: 0.2s;
  z-index: 2;
}

.input-container input:focus {
  outline: none;
}

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link rel="stylesheet" href="style.css">
</head>

<body>
  <section>
    <form action="">
      <div class="input-container">
        <input type="text" name="" id="my-input">
        <label for="my-input">name</label>
      </div>
    </form>
  </section>
</body>

</html>