
Make It Disappear
<style type="text/css">
.num_cult_posts { display: none; }
</style>

Borders
To give the num_cult_posts text a border:
<style type="text/css">
.num_cult_posts {
display: block;
width: 300px;
border: 1px solid red;
}
</style>
[ More Border Styles ]

Background
To set a background color:
<style type="text/css">
.num_cult_posts {
display: block;
width: 300px;
background: red;
}
</style>
Or a background image:
<style type="text/css">
.num_cult_posts {
display: block;
width: 300px;
background: url('http://www.PATH TO YOUR IMAGE.gif');
}
</style>
More on
[ Backgrounds ]

Text Styles
This section of text contains both plain and bold parts, so you can change them separately like this:
<style type="text/css">
.num_cult_posts {
color: deeppink;
font-size: 12pt;
font-variant: small-caps;
}
.num_cult_posts b {
color: aqua;
font-size: 14pt;
}
</style>
(Nb just changing .num_cult_posts will affect both the regular, and bold parts).
More
[ Text Styles ]

Positioning
To create a bit more space above and/or below these lines, you can give them a margin:
<style type="text/css">
.num_cult_posts {
margin-top: 20px;
margin-bottom: 20px;
}
</style>