<html>
<head>
<style>
#container {
width: 50%;
aspect-ratio: 2/1;
border: 1px solid black;
display: grid;
grid-template-columns: 1fr 1fr;
justify-items: end;
}
#container > div {
border: 1px solid black;
}
.blue {
background-color: lightblue;
width: 50%;
}
.red {
background-color: coral;
width: 40%;
}
.green {
background-color: lightgreen;
width: 60%;
}
</style>
</head>
<body>
<h2>justify-items: end</h2>
<div id="container">
<div class="red">RED</div>
<div class="blue">BLUE</div>