সিএসএস flex-grow

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
.container {
  display: flex;
  width: 300px;
  gap: 5px;
}

.container > div {
  width: 50px;
  height: 50px;
  background-color: coral;
}

.one {
  flex-grow: 1;
}

.two {
  flex-grow: 2;
}

.three {
  flex-grow: 3;
}
</style>
</head>
<body>

<div class="container">
  <div class="one">1</div>
  <div class="two">2</div>
  <div class="three">3</div>
</div>

</body>
</html>