Flexbox, two nested children to behave indepedently-CodePudding

In child-container 1 I would like the two grandchildren divs to behave indepedently. Aim: Grandchild 1: Left top Grandchild 2: Center spanning entire width.

=Centering grandchild 2 works fine. However, when I add grandchild 1 it behaves according to the container, cutting into the width of grandchild 2 sitting on the same line. How can I move grandchild 1 to the top left?

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

.child1 {
  background-color: blue;
  height: 10rem;
  display: flex;
  justify-content: center;
  align-items: center;
}

.child2 {
  background-color: red;
  height: 10rem;
}

.child3 {
  background-color: green;
  height: 10rem;
}

.grandchild1 {
  background-color: yellow;
}

.grandchild2 {
  background-color: purple;
  border: 1px black solid;
  flex-grow: 1;
  text-align: center;
}

<html>

<body>
  <div >
    <div >
      <div >
        <h1>Top-Left Me</h1>
      </div>
      <div >
        <h1>Center Me Entire Width</h1>
      </div>
    </div>
    <div >
      <h1>.</h1>
    </div>
    <div >
      <h1>.</h1>
    </div>
  </div>
</body>

</html>

CodePudding user response：

This will work if you set the position to absolute on .grandchild1 and set top and left to 0

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

.child1 {
  background-color: blue;
  height: 10rem;
  display: flex;
  justify-content: center;
  align-items: center;
}

.child2 {
  background-color: red;
  height: 10rem;
}

.child3 {
  background-color: green;
  height: 10rem;
}

.grandchild1 {
  background-color: yellow;
  position: absolute;
  top: 0;
  left: 0;
}

.grandchild2 {
  background-color: purple;
  border: 1px black solid;
  flex-grow: 1;
  text-align: center;
}

<html>

<body>
  <div >
    <div >
      <div >
        <h1>Top-Left Me</h1>
      </div>
      <div >
        <h1>Center Me Entire Width</h1>
      </div>
    </div>
    <div >
      <h1>.</h1>
    </div>
    <div >
      <h1>.</h1>
    </div>
  </div>
</body>

</html>

CodePudding user response：

.grandchild2 need to be set to:

{
    width: 100%; // take full width of a row
    position: absolute; // do not affect the .grandchild1
}

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

.child1 {
  background-color: blue;
  height: 10rem;
  display: flex;
  align-items: flex-start;
}

.child2 {
  background-color: red;
  height: 10rem;
}

.child3 {
  background-color: green;
  height: 10rem;
}

.grandchild1 {
  background-color: yellow;
}

.grandchild2 {
  align-self: center;
  width: 100%;
  position: absolute;
  background-color: purple;
  border: 1px black solid;
  text-align: center;
}

<div >
  <div >
    <div >
      <h1>Top-Left Me</h1>
    </div>
    <div >
      <h1>Center Me Entire Width</h1>
    </div>
  </div>
  <div >
    <h1>.</h1>
  </div>
  <div >
    <h1>.</h1>
  </div>
</div>