Prevent flex item from overflowing flex container

Question

In the code below, is there any way to make .inner not overflow .outer?

I don't want .inner to change the height of .outer.

And I want to get rid of the body scrollbar.

html, body {
  height: 100vh;
}

body, div {
  margin: 0;
  padding: 0;
}

.outer {
  height: 100%;
  display: flex;
  flex-flow: column;
  align-content: stretch;
}

.inner {
  display: flex;
  flex: 0 0 auto;
  align-items: stretch;
  height: auto;
  max-height: 100%;
}

.column {
  border: 1px solid #000;
  overflow-y: auto;
  margin: 0 10px;
}

.column-left {
  width: 25%;
}

.column-right {
  height: 100%;
  width: 75%;
  display: flex;
  flex-flow: column;
}

.content {
  overflow: auto;
}

.controls {
}

<div class="outer">
  <h1>
    Heading of different height
  </h1>
  <div class="inner">
    <div class="column column-left">
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
    </div>
    <div class="column column-right">
      <div class="content">
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
      </div>
      <div class="controls">
        Variable height
        <br>
        1
      </div>
    </div>
  </div>
</div>

https://codepen.io/anon/pen/jYxXKQ

Answer 1

Much of the CSS in your code can be removed.

It's not necessary or conflicts with useful flex settings.

Just use flex properties to achieve the layout.

.outer {
  height: 100vh;
  display: flex;
  flex-flow: column;
}

.inner {
  display: flex;
  flex: 1;
  min-height: 0; /* https://stackoverflow.com/q/36247140/3597276 */
}

.column {
  overflow-y: auto;
  margin: 0 10px;
  border: 1px solid #000;
}

.column-left {
  flex: 0 0 25%;
}

.column-right {
  flex: 1;
  display: flex;
  flex-flow: column;
}

body, div {
  margin: 0;
  padding: 0;
}

<div class="outer">
  <h1>Heading of different height</h1>
  <div class="inner">
    <div class="column column-left">
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
    </div>
    <div class="column column-right">
      <div class="content">
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
      </div>
      <div class="controls">
        Variable height
        <br> 1
      </div>
    </div>
  </div>
</div>

https://codepen.io/anon/pen/VydvWR

Answer 2

Well I've made it myself, hope this will help someone.

The idea is to make another wrapper around .inner and make it occupy FREE space of .outer. You can see it as .inner-wrap in code below.

That wrapper must be position: relative, and .inner must be position: absolute, so we can then make .inner occupy ALL space of .inner-wrapper by setting left, top, right and bottom to zero.

html, body {
  height: 100vh;
}

body, div {
  margin: 0;
  padding: 0;
}

.outer {
  height: 100%;
  display: flex;
  flex-flow: column;
  align-content: stretch;
  align-items: stretch;
}

.inner-wrap {
  position: relative;
  flex: 1;
}

.inner {
  display: flex;
  align-items: stretch;
  align-content: stretch;
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
}

.column {
  border: 1px solid #000;
  overflow-y: auto;
  margin: 0 10px;
}

.column-left {
  width: 25%;
}

.column-right {
  width: 75%;
  display: flex;
  flex-flow: column;
}

.content {
  overflow: auto;
}

.controls {
}

<div class="outer">
  <h1>
    Heading of different height
  </h1>
  <div class="inner-wrap">
    <div class="inner">
      <div class="column column-left">
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
      </div>
      <div class="column column-right">
        <div class="content">
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
          <h2>Row</h2>
        </div>
        <div class="controls">
          Variable height
          <br>
          1
        </div>
      </div>
    </div>
  </div>
</div>

https://codepen.io/anon/pen/GyGKpx

Answer 3

I adchieved this with flex and overflows, maybe this can suits better to you code.

html, body {
  height: 100%;
}

body, div {
  margin: 0;
  padding: 0;
}

.outer {
  height: 100%;
  display: flex;
  flex-flow: column;
}

.inner {
  display: flex;
  height: 100%;
}

.column {
  border: 1px solid #000;
  overflow-y: auto;
  margin: 0 10px;
}

.column-left {
  width: 25%;
}

.column-right {
  height: 100%;
  width: 75%;
  display: flex;
  flex-flow: column;
}

.content {
  overflow: auto;
}

<div class="outer">
  <h1>
    Heading of different height
  </h1>
  <div class="inner">
    <div class="column column-left">
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
      <h2>Row</h2>
    </div>
    <div class="column column-right">
      <div class="content">
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
        <h2>Row</h2>
      </div>
      <div class="controls">
        Variable height
        <br>
        1
      </div>
    </div>
  </div>
</div>