<header class="page-header">
    <h1>Cute Puppies Express!</h1>
</header>

<main>
    <p>I love beagles <em>so</em> much! Like, really, a lot. They’re adorable and their ears are so, so snuggly soft!</p>
</main>

header.page-header {
    background: no-repeat left/cover url(/media/examples/puppy-header-logo.jpg);
    display: flex;
    height: 120px;
    min-width: 120px;
    align-items: center;
    color: #fff;
    text-shadow: #000 0 0 .2em;
}

header.page-header > h1 {
    font: bold calc(1em + 2 * (100vw - 120px) / 100) 'Dancing Script', cursive,
        fantasy;
    margin: 2%;
}

main {
    font: 1rem 'Fira Sans', sans-serif;
}