具有绝对位置的元素在嵌套树中的相对定位元素后面并且z-index没有效果

Question

我有一个嵌套的表，我必须在其中显示文本的工具提示。我已经在jsfiddle中提取了问题，问题是即使我设置Block 2.1 Content非常大，我也无法将蓝色元素定位在z-index之上。

这里再次使用html和css代码：

.block {
  display: block;
}

.content {
  border: 1px solid #ccc;
  padding: 2px 5px;
  box-shadow: 5px 5px 10px black;
  height: 30px;
  width: 90%;
  line-height: 30px
}

.block1_content {
  z-index: 3;
  position: relative;
  background: white;
}

.block2_content {
  z-index: 2;
  margin-left: 10px;
  position: relative;
  background: #ccc;
}

.tooltip {
  position: absolute;
  display: block;
  background: blue;
  color: white;
  height: 40px;
  width: 100px;
  z-index: 99999;
  padding: 5px 10px;
  top: 15px
}

<div class="block1 block">
  <div class="block1_content content">Block 1 Content</div>
  <div class="block2 block">
    <div class="block2_content content">
      Block2 Content
      <div class="tooltip">Tooltip</div>
    </div>
  </div>
</div>
<div class="block1 block">
  <div class="block1_content content">Block 2.1 Content</div>
  <div class="block2 block">
    <div class="block2_content content"> Block 2.2 Content</div>
  </div>
</div>

编辑

Here根据要求提供了一些有点复杂的代码/问题版本。

Answer 1

希望这能帮助你。谢谢

.block {
  display: block;
}
.relative{
  position: relative
}

.content {
  border: 1px solid #ccc;
  padding: 2px 5px;
  box-shadow: 5px 5px 10px black;
  height: 30px;
  width: 90%;
  line-height: 30px
}

.block1_content {
  z-index: 3;
  position: relative;
  background: white;
}

.block2_content {
  z-index: 2;
  margin-left: 10px;
  position: relative;
  background: #ccc;
}

.tooltip {
  position: absolute;
  display: block;
  background: blue;
  color: white;
  height: 40px;
  width: 100px;
  z-index: 99999;
  padding: 5px 10px;
  top: 15px
}

<div class="block1 block">
  <div class="block1_content content">Block 1 Content</div>
  <div class="block2 block">
    <div class="block2_content content">
      Block2 Content
      
    </div>
  </div>
</div>
<div class="block1 block relative">
<div class="tooltip">Tooltip</div>
  <div class="block1_content content">Block 2.1 Content</div>
  <div class="block2 block">
    <div class="block2_content content"> Block 2.2 Content</div>
  </div>
</div>