grid-template

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>specify-grid-columns-rows-and-areas-at-once-with-the-grid-template-shorthand</title>
    <style>
        .container > * {
            background-color: navajowhite;
            color: white;
            font-size: 40px;
        }

        .container {
            display: grid;
            height: 100vh;
            grid-gap: 10px;
            grid-template:
                [nav-start] "nav-1 nav-2 nav-3" 1fr [nav-end]
                [main-start] "main main nav-3" 5fr [main-end]
                / 2fr auto 1fr;
            /*
                [named grid row line start] "area1 area2 ..." 1fr [named-grid-line end]
            */
        }

        nav:nth-of-type(1) {
            grid-area: nav-1;
        }
        nav:nth-of-type(2) {
            grid-area: nav-2;
        }
        nav:nth-of-type(3) {
            grid-area: nav-3;
        }
        section:only-of-type {
            grid-area: main;
        }
    </style>
</head>
<body>
<div class="container">
    <nav>Menu 1</nav>
    <nav>Menu 2</nav>
    <nav>Menu 3</nav>
    <section>Main</section>
</div>
</body>
</html>

// Code goes here

/* Styles go here */