<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width">
    <title>CSS Grid - line-based placement starting point</title>
    <style>
        body {
            width: 90%;
            max-width: 900px;
            margin: 2em auto;
            font: .9em/1.2 Arial, Helvetica, sans-serif;
        }

        .container {
            display: grid;
            grid-template-columns: repeat(12, minmax(0,1fr));
            gap: 20px;
      