title: Bootstrap 4 making grids take up 100% height of the rest of the page
body: <p>I'm currently in the process of learning Bootstrap and I'm still fairly new, so please go easy on me. I'm trying to make a page where there is a main heading for the page, a heading above the grids, and 3 unequal responsive grids than span the height of the rest of the page, even when the browser is resized. I've tried setting height or row and each div to 100%, I also tried looking this up but I didn't find anything of much use, and I'm not sure how I would achieve this, Thanks for taking the time to help. Code is:</p>
  
  <p>EDIT: To specify, my issue is getting the remaining area to take up 100% of space, not a div taking up 100% of the page, just the remaining part</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-css lang-css prettyprint-override"><code>.div1 {
    background-color:red;
  }
  
  .div2 {
    background-color:gray;
  }
  
  .div3 {
    background-color:blue;
  }
  
  .row {
    height: 100%;
  }
  
  #main {
    background-color: yellow;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>    &lt;!DOCTYPE html&gt;
      &lt;html&gt;
        &lt;html lang="en"&gt;
      &lt;head&gt;
        &lt;meta charset="utf-8"&gt;
      &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"&gt;&lt;/script&gt;
      &lt;link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css"&gt;
      &lt;script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js"&gt;&lt;/script&gt;
      &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.6/umd/popper.min.js"&gt;&lt;/script&gt;
      
      &lt;/head&gt;
      &lt;body&gt;
        
      &lt;link rel="stylesheet" href="test.css"&gt;
      &lt;script src="test.js"&gt;&lt;/script&gt;
      &lt;h1&gt;Welcome&lt;/h1&gt;
      &lt;div class="container-fluid" id="main"&gt;
        &lt;h1&gt;This is a heading&lt;/h1&gt;
        
        &lt;div class="row"&gt;
          &lt;div class="col-sm-3 div1"&gt;Left side&lt;/div&gt;
          &lt;div class="col-sm-6 div2"&gt;Middle&lt;/div&gt;
          &lt;div class="col-sm-3 div3"&gt;Right side&lt;/div&gt;
        &lt;/div&gt;
      &lt;/div&gt;
      
      &lt;/body&gt;
      &lt;/html&gt;</code></pre>
  </div>
  </div>
  </p>