Question: Is it possible to access to a var or a function that is in another file?. In this case, when the user click to #linkajax can he get what is in var test? how can I do it? I tried this and it does not work

JQUERY AJAX:

```
$("#linkajax").click(function(){
    $("#target").load("extern.html");
    $('#target').text(test);
});

```

INDEX.HTML:

```
<div id="linkajax">just clic!</div>
<br>
<div id="target"></div>

```

EXTERN.HTML:

```
<script type="text/javascript">
var test = "test text"; 
</script>

```

Answer: 
Changing a theme is usually done by loading in another class with JQuery.
For example:

HTML:

```
<body id='skin' class="skin-blue">

```

JQuery:

```
$('#skin').addClass('skin-red').removeClass('skin-blue');

```

To change a font-size easily, consider something like this for example:

```
var size = 20;
    function setFontSize(s) {
        size = s;
        $('#sidebar-menu').css('font-size', '' + size + 'px');
        $('#content').css('font-size', '' + size + 'px');
    }
    function increaseFontSize() {
        setFontSize(size + 5);
    }
    function decreaseFontSize() {
        if(size > 5)
            setFontSize(size - 5);
    }

    $('#inc').click(increaseFontSize);
    $('#dec').click(decreaseFontSize);
    setFontSize(size);

```

and for example a + and - button

```
 <li class="dropdown tasks-menu">
   <li>
     <a href="#" class="dropdown-toggle" data-toggle="dropdown">
       <i class="fa fa-fw fa-plus" id="inc"></i>
     </a>
   </li>
 </li>
 <li class="dropdown tasks-menu">
   <li>
     <a href="#" class="dropdown-toggle" data-toggle="dropdown">
       <i class="fa fa-fw fa-minus" id="dec"></i>
     </a>
   </li>
</li>

```
You can put a div before the link tag and use getElementById.innerHTML and change the contents to your desired css