How do i centre a div in angular 5 - html

Question

I am using Angular5, and I have tried to set margin: 0 auto as well as setting left: 50% and top: 50% but the margin doesn't do anything and setting left to 50% only aligns the side of the div to the middle and doesn't move the div down at all.
How do I align the div #loading to the middle?
My code:
#loading, #outlet {
width: 100%;
height: 100%;
position: absolute;
}
#loading{
z-index: 10;
height: 100px;
width: 200px;
background-color: rgba(255,255,255,0.85);
padding: 40px;
border: 1px solid #d3d3d3;
border-radius: 5px;
margin: 0 auto;
margin-bottom:10px;
box-shadow: 0px 1px 3px rgba(0,0,0,0.5);
}
#app{
position: relative;
}
<div id="app">
<div id="outlet">
<router-outlet></router-outlet>
</div>
<div id="loading" *ngIf="data.Loading">
<h2>Loading...</h2>
</div>
</div>
I am also overlaying the #loading div over #outlet.

Answer 1

The problem you are having is because of the position: absolute thing that you have assigned to both #loading and #outlet. You can solve the issue with this code. Try this.
<div id="app">
<div id="wrap">
<div id="outlet">
<router-outlet></router-outlet>
</div>
<div id="loading" *ngIf="data.Loading">
<h2>Loading...</h2>
</div>
</div>
</div>
#wrap {
margin: 0 auto;
width: 200px;
}
#loading, #outlet {
width: 100%;
height: 100%;
position: absolute;
}
#loading{
z-index: 10;
height: 100px;
width: 200px;
background-color: rgba(255,255,255,0.85);
padding: 40px;
border: 1px solid #d3d3d3;
border-radius: 5px;
margin: 0 auto;
margin-bottom:10px;
box-shadow: 0px 1px 3px rgba(0,0,0,0.5);
}
#app{
position: relative;
width: 100%;
}

Answer 2

To align the text in the center, use text-align: center:
#loading, #outlet {
width: 100%;
height: 100%;
}
#loading{
z-index: 10;
height: 100px;
width: 200px;
background-color: rgba(255,255,255,0.85);
padding: 40px;
border: 1px solid #d3d3d3;
border-radius: 5px;
text-align: center;
margin-bottom:10px;
box-shadow: 0px 1px 3px rgba(0,0,0,0.5);
}
#app{
position: relative;
}
<div id="app">
<div id="outlet">
<router-outlet></router-outlet>
</div>
<div id="loading" *ngIf="data.Loading">
<h2>Loading...</h2>
</div>
</div>
To align the box in the center, use margin: auto, but DO NOT use position: absolute:
#loading, #outlet {
width: 100%;
height: 100%;
}
#loading{
z-index: 10;
height: 100px;
width: 200px;
background-color: rgba(255,255,255,0.85);
padding: 40px;
border: 1px solid #d3d3d3;
border-radius: 5px;
margin: auto;
margin-bottom:10px;
box-shadow: 0px 1px 3px rgba(0,0,0,0.5);
}
#app{
position: relative;
}
<div id="app">
<div id="outlet">
<router-outlet></router-outlet>
</div>
<div id="loading" *ngIf="data.Loading">
<h2>Loading...</h2>
</div>
</div>
Then if you put those two together, you get:
#loading, #outlet {
width: 100%;
height: 100%;
}
#loading{
z-index: 10;
height: 100px;
width: 200px;
background-color: rgba(255,255,255,0.85);
padding: 40px;
border: 1px solid #d3d3d3;
border-radius: 5px;
margin: auto;
text-align: center;
margin-bottom:10px;
box-shadow: 0px 1px 3px rgba(0,0,0,0.5);
}
#app{
position: relative;
}
<div id="app">
<div id="outlet">
<router-outlet></router-outlet>
</div>
<div id="loading" *ngIf="data.Loading">
<h2>Loading...</h2>
</div>
</div>