Flexbox

align-content: stretch (default)

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: stretch;
}
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align-content: flex-start

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: flex-start;
}
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Box-9

align-content: stretch)

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: center;
}
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Box-9

align-content: flex-end

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: flex-end;
}
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Box-9

align-content: space-between

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: space-between;
}
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Box-9

align-content: space-around

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: space-around;
}
Box-1
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Box-9

align-content: space-evenly

CSS
.container {
  display: flex;
  flex-wrap: wrap;
  height: 600px;
  align-content: space-evenly;
}
Box-1
Box-2
Box-3
Box-4
Box-5
Box-6
Box-7
Box-8
Box-9