I know there so many ways lead to this layout, but I saw this one recently and I don’t know if it’s a good way

I’m not that new at css but recently I saw some new tricks for me but should I use this code or should I try another way?, maybe grid or something?

body{
display: flex;
justify-content:center;
padding:0;
margin:0;
}
.flex-container {
background: lightsteelblue;
margin-bottom: 10px;
width: 100%;
display: flex;
Height:900px;
flex-wrap: wrap-reverse;

}
.flex-item {
box-sizing: border-box;
border: 1px solid midnightblue;
padding: 10px;
flex: 1 1 50%;
}