Question

我试图相对于其相对定位的祖父母定位元素的绝对位置::before。它的父级没有定位，但是top和left尊重父级而不是祖父母。

* {
  box-sizing: border-box;
}

::-webkit-input-placeholder,
::-moz-placeholder {
  color: #9b9b9b;
}

.field {
  height: 43px;
  display: flex;
  flex-direction: column-reverse;
  position: relative;
}
input,
label {
  display: block;
}
input {
  font-size: 14px;
  border: 0;
  border-bottom: 1px solid #F2F2F2;
  border-radius: 0;
  padding: 3px 0 10px 0;
  background-color: transparent;
}
input:focus {
  outline: 0;
  border-bottom: 1px solid #D66C9C;
}
label {
  font-size: 12px;
  color: #9b9b9b;
  transform: translateY(20px);
  transition: all 0.2s;
}
input:focus + label {
  color: #808080;
  transform: translateY(0);
}
input:focus + label::before {
  content: "";
  width: 5px;
  height: 5px;
  display: block;
  background-color: #d66c9c;
  transform: rotate(45deg) translateY(-50%);
  position: absolute;
  left: 0;
  bottom: 0;
}

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>
</head>
<body>
<div class="field">
  <input type="text" id="fullname">
  <label for="fullname">Name</label>
</div>
</body>
</html>

Answer 1

* {
  box-sizing: border-box;
}

::-webkit-input-placeholder,
::-moz-placeholder {
  color: #9b9b9b;
}

.field {
  height: 43px;
  display: flex;
  flex-direction: column-reverse;
  position: relative;
}
input,
label {
  display: block;
}
input {
  font-size: 14px;
  border: 0;
  border-bottom: 1px solid #F2F2F2;
  border-radius: 0;
  padding: 3px 0 10px 0;
  background-color: transparent;
}
input:focus {
  outline: 0;
  border-bottom: 1px solid #D66C9C;
}
label {
  font-size: 12px;
  color: #9b9b9b;
  transform: translateY(20px);
  transition: all 0.2s;
  position:relative;
}
input:focus + label {
  color: #808080;
  transform: translateY(0);padding:0 0 0 5px;
}
input:focus + label::before {
  content: "";
  width: 5px;
  height: 5px;
  display: block;
  background-color: #d66c9c;
  transform: rotate(45deg) translateY(-50%);
  position: absolute;
  left: -8px;
  bottom:5px;
}

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>
</head>
<body>
<div class="field">
  <input type="text" id="fullname">
  <label for="fullname">Name</label>
</div>
</body>
</html>

检查这个希望，这样对您有用

CSS：相对于相对祖父母，绝对位置::: before

1 个答案: