sidemenu CSS property

HTML

<html>
  <head>
    <meta name="description" content="sidemenu 1 layer">
    <script src="https://cdn.layerjs.org/libs/layerjs/layerjs-0.6.1.min.js"></script>
    <link href="https://cdn.layerjs.org/libs/layerjs/layerjs-0.6.1.css" type="text/css" rel="stylesheet" /> 

  </head>

  <body>
  <div lj-type="stage"> <!-- Add a stage. -->
    <div lj-type="layer" lj-default-frame="frame1"> <!-- The layer for the main content -->
      <div lj-type="frame" lj-name="frame1" class="content" lj-fit-to="responsive-width"> <!-- The content of the current page -->
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          sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo
          duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p>
        <p> Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no
          sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo
          duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p>
        </div>
      </div>
    <div lj-type="layer" lj-name="menulayer" lj-native-scroll="false"> <!-- The layer for the menu on top of the main content -->
      <div...

CSS

body, html {
  height: 100%;
}

body
{
    padding: 0px;
    margin: 0px;
}

[lj-type="stage"]
{
    width: 100%;
    height: 100%;
    margin: auto;
    background-color: white;
}


.menu
{
    width: 200px;
    box-shadow: 0px 0px 10px 1px #888;
    
}

@media (max-width: 600px) {
    .menu {
        --lj-fit-to: responsive;
        --lj-transition: fade;
    }
}

.content
{
    box-sizing: border-box;
    padding: 60px 20px;
}

.close
{
    position: absolute;
    right: 0px;
    padding: 5px;
    text-decoration: none;
    cursor: pointer;
    color: black;
}

.nav a
{
    text-decoration: none;
    color: inherit;
}

.nav
{
    background-color: #58585A;
    color: #ccc;
    font-family: Helvetica Neue, Helvetica, Arial;
}

.nav-list
{
    list-style: none;
    margin: 0px;
    padding: 0px;
}

.nav-item
{
    padding: 10px 20px;
    border-bottom: 1px solid #666;
    cursor: pointer;
}

.nav-item:hover
{
    background-color: #eee;
    color: #777;
}

.nav-hor
{
    box-sizing: border-box;
    padding: 10px 20px;
    border-bottom: 1px solid #eee;
}


.nav-hor:hover
{
    background-color: #58585A;
}