title: Making nav bar slide into view from top
body: <p>I currently have the following code in my angular app (2+):</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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  <pre class="snippet-code-css lang-css prettyprint-override"><code>.header {
    background: rgba(white, 0);
    &amp;.fixed-top {
      background: rgba(white, 1);
      border-bottom: solid whitesmoke 1px;
      position: fixed;
      top: 0;
      right: 0;
      left: 0;
      z-index: 1030;
    }
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;nav class="navbar navbar-toggleable-sm header" [class.fixed-top]="stickyHeader" (scroll)="scrollHandler()"&gt;...&lt;/nav&gt;</code></pre>
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  <p>The <code>handleScroll()</code> function simply sets <code>stickyHeader</code> to <code>true</code> after the user scrolls down "enough" pixels, and so the header menu becomes sticky. Here it is:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>stickyHeader = false;
  
  @HostListener('window:scroll', [])
  scrollHandler() {
    this.stickyHeader = window.scrollY &gt; 90;
  }</code></pre>
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  <p>My question is: how can I make that menu appear to slide (animated) from top, as if it descended from above the browser?! </p>