<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
div {
border: 1px solid #0011ff;
}
.content-container {
padding: 20px 0;
}
.content-container div {
display: inline-block;
}
.right {
width: 90px;
}
.left {
width: calc(100% - 100px);
}
</style>
</head>
<body>
<div class="content-container">
<div class="left">Some text</div>
<div class="right">Some text</div>
</div>
</body>
</html>