html - 如何仅在顶部将 box-shadow inset 添加到 textarea？

Question

我在将 box-shadow 添加到我的文本区域时遇到问题。下图描述了我正在努力实现的目标。

CSS 代码:

.text_area {
  position: relative;
  box-sizing: border-box;
  width: 100%;
  height: 120px;
  resize: none;
  outline: none;
  padding: 5 10px;
  border: none;
  background: #ffffff;
  font-size: 13px;
  color: #292c2e;
  letter-spacing: 0;
}

.text_area::placeholder {
  position: absolute;
  top: 50%;
  left: 0;
  color: #e3e3e3;
}

如果有人知道如何正确添加 box-shadow inset 请写信给我!

Answer 1

我能想到的实现这一点的唯一方法是将 textarea 包装到另一个元素中并使用伪元素添加渐变。这是因为 textarea 不是 block 级元素(不能在其中包含其他元素)。

看这个例子:

.wrapper {
  height: 500px;
  width: 500px;
  resize: both;
  position: relative;
}

textarea {
  width: 100%;
  height: 100%;
  resize: none;
  box-sizing: border-box;
}

.wrapper::after {
  background-image: linear-gradient(white, transparent);
  position: absolute;
  z-index: 2;
  content: "";
  top: 0;
  left: 0;
  height: 20%;
  width: 100%;
  pointer-events: none;
}

<div class='wrapper'>
  <textarea>
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</textarea>
</div>