Auto grid sizing allowing nth max in a row in css

Question

I am trying to Auto-Sizing Columns in CSS Grid. Like if I have one child-div it will cover full space in mother-div. But if there are multiple child-div it will allow specific number of child-div in a row . Here I am using CSS grid. But I cant do it. Here is my code

<div class="mother-div">
   <div class="child-div>
   </div>
   <div class="child-div>
   </div>
</div> 

css

.child-div {
    background-color: #257790;
    height: 100px;
    width: 100%;
}

.mother-div {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr 1fr;
    grid-gap: 1em;
}

Answer 1

What you are looking is almost automatic, grid will behave like this almost out of the box.

You only need to set grid-auto-flow to the direction that you want

To limit the number of items per row, you need to set them to a specific column, using nth-child selector

this style:

.child-div:nth-child(5n+1) {
    grid-column: 1;
}

selects childs for n values 0, 1, 2, and so on, that in the formula 5n+1 gives values 1, 6, 11, 16, ...

All those children will go to column 1, that matches the requirement for 5 elements per row.

.child-div {
    background-color: #257790;
    height: 50px;
    width: 100%;
}

.child-div:nth-child(5n+1) {
    grid-column: 1;
}
.child-div:nth-child(5n+2) {
    grid-column: 2;
}
.child-div:nth-child(5n+3) {
    grid-column: 3;
}
.child-div:nth-child(5n+4) {
    grid-column: 4;
}
.child-div:nth-child(5n) {
    grid-column: 5;
}

.mother-div {
    margin: 10px;
    width: 500px;
    border: solid 3px black;
    display: grid;
    grid-gap: 1em;
    grid-auto-flow: column; 
}

<div class="mother-div">
   <div class="child-div">
   </div>
</div> 
<div class="mother-div">
   <div class="child-div">
   </div>
   <div class="child-div">
   </div>
</div>
<div class="mother-div">
   <div class="child-div">1
   </div>
   <div class="child-div">2
   </div>
   <div class="child-div">3
   </div>
   <div class="child-div">4
   </div>
   <div class="child-div">5
   </div>
   <div class="child-div">6
   </div>
</div>