<h1><code>align-items: flex-start</code></h1>
<div class="container flex-start">
      <div class="item item-1">1</div>
      <div class="item item-2">2</div>
      <div class="item item-3">3</div>
      <div class="item item-4">4</div>
</div>

<h1><code>align-items: flex-end</code></h1>
<div class="container flex-end">
      <div class="item item-1">1</div>
      <div class="item item-2">2</div>
      <div class="item item-3">3</div>
      <div class="item item-4">4</div>
</div>

<h1><code>align-items: center</code></h1>
<div class="container center">
      <div class="item item-1">1</div>
      <div class="item item-2">2</div>
      <div class="item item-3">3</div>
      <div class="item item-4">4</div>
</div>

<h1><code>align-items: baseline</code></h1>
<div class="container baseline">
      <div class="item item-1">1</div>
      <div class="item item-2">2</div>
      <div class="item item-3">3</div>
      <div class="item item-4">4</div>
</div>

<h1><code>align-items: stretch</code></h1>
<div class="container stretch">
      <div class="item item-1">1</div>
      <div class="item item-2">2</div>
      <div class="item item-3">3</div>
      <div class="item item-4">4</div>
</div>
html {
  background: #fff7f6;
}
h1 {
  color: DarkSlateGrey;
  font-weight: normal;
  font-size: 1.5em;
}
/*-- --*/
.container {
  display: flex;
  flex-wrap: wrap;
  flex-direction: row;
}
.container.flex-start {
  align-items: flex-start;
}
.container.flex-end {
  align-items: flex-end;
}
.container.center {
  align-items: center;
}
.container.baseline {
  align-items: baseline;
}
.container.stretch {
  align-items: stretch;
}
.item {
  font-size: 2rem;
  line-height: 1;
  text-align: center;
  padding: 3rem;
  background: mistyrose;
  border: 3px solid tomato;
  color: tomato;
  margin: 6px;
}
.item.item-2 {
  padding: 5rem;
}
.item.item-3 {
  padding: 1.5rem;
}
.item.item-4 {
  padding: .5rem 2rem 3rem;
}

External CSS

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External JavaScript

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