Hello!

Here's a simple tutorial on how to set your forum width using CSS, since some people do encounter problems while changing the forum width in a normal way (ACP > General > Forum > Configuration > Pages Structure > Forum Width).

- For PunBB: (All you need to do is to change the value 80 to your desired % width)

Code:

.pun {
width: 80% !important;
}

- For PhpBB2: (All you need to do is to change the value 80 to your desired % width)

Code:

.bodylinewidth {
width: 80% !important;
}

- For PhpBB3: (All you need to do is to change the value 80 to your desired % width)

Code:

#wrap {
width: 80% !important;
}

- For Invision: (All you need to do is to change the value 80 to your desired % width)

Code:

#ipbwrapper {
width: 80% !important;
}

Have fun! :):