change background image of div when hovering over link
<p>I have a navigation menu and i'd like the background image of an adjacent div to change to a different image when i hover over each of the menu links . I've tried using jquery to add the class of side-menu1 which has a different background image . this would then need to be replicated for each of the 5 links</p>

<pre class="lang-js prettyprint-override"><code>$(document).ready(function() {
  $('.evo').hover(function() {
    $('.side-menu').addClass('.side-menu1');
  }, function() {
    $('.side-menu').removeClass('.side-menu1');
  });
});
</code></pre>

<pre class="lang-css prettyprint-override"><code>nav {
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  width: 100%;
  text-align: left;
  box-sizing: border-box;
  z-index: 10001;
  left: -100%;
}

nav ul {
  width: 50%;
  float: left;
  list-style-type: none;
  padding: 0;
  height: 100%;
  margin: 0;
}

nav ul li {
  width: 100%;
  height: 20%;
  box-sizing: border-box;
  padding-top: 9vh;
  background: rgba(0, 0, 0, 1);
  transition: all 1s;
  position: relative;
  padding-left: 80px;
}

nav ul li a {
  font-family: 'battle';
  color: white;
  font-size: 14px;
  letter-spacing: 14px;
  text-decoration: none;
}

nav ul li:hover {
  background: rgba(0, 0, 0, 0.95);
}

.underline {
  position: absolute;
  bottom: 60px;
  left: 0;
  height: 1px;
  background: rgba(38, 157, 171, 0.8);
  width: 0%;
  transition: all 1s ease-in-out;
  display: block;
  z-index: 10001;
  margin-left: 80px;
}

nav ul li:hover .underline {
  width: 260px;
}

.side-menu {
  height: 100%;
  width: 50%;
  float: left;
  background-image: url(../img/menu-donut.png);
  transition: all 1s ease-in-out;
}

.side-menu1 {
  background-image: url(../img/menu-hci.png);
}
</code></pre>

<pre class="lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"&gt;&lt;/script&gt;
&lt;nav class="slideout-menu"&gt;
  &lt;ul&gt;
    &lt;li&gt;
      &lt;a href="#"&gt;POTOCKI&lt;/a&gt;&lt;span class="underline"&gt;&lt;/span&gt;
    &lt;/li&gt;
    &lt;li class="evo"&gt;
      &lt;a href="#"&gt;EVOLUTION&lt;/a&gt;&lt;span class="underline"&gt;&lt;/span&gt; 
    &lt;/li&gt;
    &lt;li&gt;
      &lt;a href="#"&gt;COLOUR IDEAS&lt;/a&gt;&lt;span class="underline"&gt;&lt;/span&gt;
    &lt;/li&gt;
    &lt;li&gt;
      &lt;a href="#"&gt;FAT DONUT&lt;/a&gt;&lt;span class="underline"&gt;&lt;/span&gt;
    &lt;/li&gt;
    &lt;li&gt;
      &lt;a href="#"&gt;SEAN CARVER&lt;/a&gt;&lt;span class="underline"&gt;&lt;/span&gt;
    &lt;/li&gt;
  &lt;/ul&gt;
  &lt;div class="side-menu"&gt;&lt;/div&gt;
&lt;/nav&gt;
</code></pre>