If you want to have completely different sidebars (different links or news etc) or different sidebar skins in different forums, you will need to do that using Forum Specific Skins, changing the sidebar in that way is not possible using the method in this post, it is only for showing or hiding a sidebar.
The code in this post is designed to work with this FAQ - sidebars and new sidebar wizard
How to find out the forum ID
On the main page of your domain click on the forum you want to apply a background to. Inside the forum, look at the address bar of your browser.
The number circled in red (it will be different depending on the forum) is the number you need. Make a note of it.
Hiding a Sidebar
If you have a sidebar that you only want to hide in a few forums, that is the sidebar is show by default and hidden in only a few forums, then follow this
template:
.forum54 .sidebarholder { display: none; }
.forum54 .forumholder { margin-left: auto; }
The number in red is what you just noted down from the address bar. You can do this with as many of your forums as you need to hide your sidebar in
.forum54 .sidebarholder { display: none; }
.forum54 .forumholder { margin-left: auto; }
.forum55 .sidebarholder { display: none; }
.forum55 .forumholder { margin-left: auto; }
.forum60 .sidebarholder { display: none; }
.forum60 .forumholder { margin-left: auto; }
.forum90 .sidebarholder { display: none; }
.forum90 .forumholder { margin-left: auto; }
Showing a Sidebar
If you only want to show your sidebar in a few forum, that is the sidebar is hidden by default and only shown with a
few exceptions then you would use this code instead.
/* do not duplicate these two lines */
.forumholder { margin: auto; }
.sidebarholder { display: none; }
/* now show the sidebar in a specific forum */
.forum54 .sidebarholder { display: block; }
.forum54 .forumholder { margin-left: 170px; }
You would add that code for each forum you want to show the sidebar in until you end up with the following or something similar
/* do not duplicate these two lines */
.forumholder { margin: auto; }
.sidebarholder { display: none; }
/* now show the sidebar in a specific forum */
.forum54 .sidebarholder { display: block; }
.forum54 .forumholder { margin-left: 170px; }
.forum60 .sidebarholder { display: block; }
.forum60 .forumholder { margin-left: 170px; }
.forum90 .sidebarholder { display: block; }
.forum90 .forumholder { margin-left: 170px; }
.forum87 .sidebarholder { display: block; }
.forum87 .forumholder { margin-left: 170px; }
If instead you are using a right sidebar, change margin-left to margin-right.
