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CSS

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JavaScript

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HTML 

              
                <div class="container">
  <header class="header">HEADER</header>
  <nav class="menu">MENU</nav>
  <article>
    <p>Lorem ipsum, dolor sit amet consectetur adipisicing elit. Hic, labore. Error quis aliquam omnis doloribus blanditiis, quisquam quas, ipsum cum corporis incidunt inventore molestiae voluptates sequi, laudantium iure! Ab, quaerat.</p>
    <p>Doloribus nemo hic nisi dicta, tempora fugiat aspernatur officia! Nobis maxime dicta quos recusandae asperiores! Placeat, illum quaerat, expedita ratione enim adipisci distinctio molestias ipsam, itaque velit veritatis quidem assumenda?</p>
    <p>Quasi praesentium quae voluptas numquam animi ad officia facilis error dicta perspiciatis odio sint similique aspernatur rerum, iure iste nihil aliquid, molestiae totam magnam amet. Modi necessitatibus numquam aliquam excepturi.</p>
    <p>Officiis, delectus quod nemo optio rerum voluptas odit vero dolorem laudantium vitae fugit omnis molestias iure illo a maxime quam corporis voluptatibus harum minima odio doloribus eum? Similique, officiis error.</p>
    <p>Voluptatum, officiis ad? Atque accusantium necessitatibus quaerat odit voluptas sunt, adipisci iusto ab, tempore possimus molestias? Fugit reiciendis asperiores distinctio est accusantium! Velit ad impedit alias praesentium et! Dignissimos, ex!</p>
    <p>Nihil tenetur, ipsam sunt rerum modi sequi quasi voluptatem facere iusto, perspiciatis temporibus, facilis voluptatum laudantium. Exercitationem dicta earum ratione minus magni, rem libero commodi, nostrum sapiente animi ipsum quod.</p>
    <p>Perferendis sapiente, quidem ipsum repudiandae nulla vero possimus nemo dolore recusandae ipsa quibusdam error, cupiditate, ad sed velit ullam obcaecati ut! Maiores, officiis. Numquam, quia est. Consectetur laborum quia voluptatibus?</p>
    <p>Accusantium numquam quidem nesciunt voluptates esse laborum sint deleniti tenetur dolor cum. Aperiam molestias quaerat dolores commodi necessitatibus! Dolore ipsam excepturi perferendis atque iusto assumenda incidunt laudantium tempore, officia et.</p>
    <p>Obcaecati, quo. Expedita nobis illo minus nulla sapiente ut quae magnam sed tempore autem, nam distinctio eaque laboriosam odit esse quas culpa dolorem veniam earum quos aut aperiam nesciunt necessitatibus.</p>
    <p>Veritatis at eaque recusandae modi nemo. Autem laboriosam repellendus nihil rem, libero atque laudantium nesciunt culpa aliquid eveniet sapiente, pariatur suscipit praesentium rerum reprehenderit fugit blanditiis quis alias labore ipsam.</p>
  </article>
  <footer class="footer">FOOTER</footer>
</div>
!

CSS 

              
                * {
  padding: 0;
  margin: 0;
}
.container {
  position: relative;
  padding-top: 0;
}
.header,
.menu,
.footer {
  background-color: #333;
  padding: 40px 0;
  text-align: center;
  color: #fff;
  font-family: sans-serif;
  width: 100%;
  position: relative;
  z-index: 2;
}
.menu {
  position: sticky;
  top: 0;
}
.menu.fixed {
  position: fixed;
}
article {
  background-color: green;
  padding: 30px 0;
}
article p {
  width: 640px;
  max-width: 90%;
  margin: 0 auto 20px;
  font-size: 20px;
  color: #fff;
}
.header {
  background-color: blue;
}
.footer {
  background-color: purple;
}
!

JS 

              
                var $menu = $(".menu");
var $menuOffsetTop = $menu.offset().top;
var $menuHeight = $menu.outerHeight();
var $menuParent = $menu.parent();
var $menuParentPaddingTop = parseFloat($menuParent.css("padding-top"));

checkWidth();

function checkWidth() {
  // for mobile - you need change 1920 to 992
  if (window.matchMedia("(max-width: 1920px)").matches) {
    if ($menu.length !== 0) {
      $(window).scroll(onScroll);
    }
  }
}

function onScroll() {
  if ($(window).scrollTop() > $menuOffsetTop) {
    $menu.addClass("fixed");
    $menuParent.css({ "padding-top": $menuParentPaddingTop + $menuHeight });
  } else {
    $menu.removeClass("fixed");
    $menuParent.css({ "padding-top": $menuParentPaddingTop });
  }
}
!
999px

Console