<!DOCTYPE html>
<html>
  <head>
    <title>aliker</title>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
    <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css">
    <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap-theme.min.css">
    <script src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
  </head>
 <body style="padding-top:70px;">
    <nav class="navbar navbar-inverse navbar-fixed-top" role="navigation">
      <div class="container-fluid">
        <div class="navbar-header">
          <a class="navbar-brand" href="#">aliker</a>
        </div>
      </div>
    </nav>

    <div id="content" class="container-fluid">
      <form role="form">
        <div class="form-group">
          <input type="text" class="form-control" placeholder="Tumblr Post URL">
        </div>
      </form>
    </div>

    <script type="text/javascript">

    </script>
  </body>
</html>

<!DOCTYPE html>
<html>
  <head>
    <title>aliker</title>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
    <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css">
    <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap-theme.min.css">
    <script src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
  </head>
 <body style="padding-top:70px;">
    <nav class="navbar navbar-inverse navbar-fixed-top" role="navigation">
      <div class="container-fluid">
        <div class="navbar-header">
          <a class="navbar-brand" href="#">aliker</a>
        </div>
      </div>
    </nav>

    <div class="container-fluid">
      <form role="form" id="post-form">
        <div class="form-group">
          <input type="text" id="post-input" class="form-control" placeholder="Tumblr Post URL">
        </div>
      </form>

      <div id="content">

      </div>

    </div>

    <script type="text/javascript">

    </script>
  </body>
</html>

Make the input textarea stretch the entire screen
Make the input textarea stretch the entire screen
