Demo:


How to do it:
- Step 1: Go to ACP --> Display --> General --> Viewtopic_body.
- Step 2: Search for:

Code:

{postrow.displayed.SIGNATURE}

And change it into:

Code:

<div align="center">
<fieldset class="signature"><legend class="signtop"><b>Signature</b></legend>
{postrow.displayed.SIGNATURE}</fieldset></div>

You can replace the word "Signature" to any word you want.

Don't forget to save and publish this change.

- Step 3: Put the code below to your forum's CSS (ACP --> Display --> Pictures And Colors --> Colors --> CSS Stylesheet).

Code:

.signature
{
font-size:12px;
margin-top:20px;
padding:10px;
float:center;
vertical-align:bottom;
border:1px dashed #5ED7FF;
width: auto;
}
.signtop
{
font-size:12px;
padding:3px 10px 3px 10px;
margin-bottom:10px;
border:1px solid #38ABFF;
background-color:#38ABFF;
color: #FFFFFF
}

Done!