To fill columns, use the column-fill property. You can try to run the following code to implement the column-fill property, with balance form:
Example
<!DOCTYPE html>
<html>
<head>
<style>
.demo {
column-count: 4;
column-fill: balance;
}
</style>
</head>
<body>
<div class = "demo">
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text.
</div>
</body>
</html>