html div grid 9x9

1<div class="grid">
2  <div class="cell" style="background-color: green">1</div>
3  <div class="cell" style="background-color: red">1</div>
4  <div class="cell" style="background-color: blue">1</div>
5  <div class="cell" style="background-color: yellow">1</div>
6</div>

1.grid {
2  display: flex;
3  flex-wrap: wrap;
4  align-items: flex-end;
5}
6
7.cell {
8  flex: 0 0 33%;
9  height: 100px;
10  width: 100px;
11  margin-bottom: 5px;
12}