This is a basic guideline of the CSS Code methods.
Replace xxxxxx with actual colors.
---------------
.cb{background-color:#xxxxxx}
THIS Puts a small halo around the comments box. (minor effect)
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.chd{background-color:#xyxyxy;font-family:arial;font-weight:bold;color:#ffffff}
SUBJECT LINE (Subject /Author /Date /Msgs)
(You can change xyxyxy into 6-digit # of your choice)
------
.c1{background-color:#xxxxxx}
TOPICS (example: 8 Basic Steps for Beginners)
------
.c2{background-color:#xxxxxx}
Messages AND Body (this forum uses Yellow)
------
.cp{background-color:#xxxxxx}
The Comment Box (bright BLUE on this forum)
------
.va{color:#000099;font-style:italic;font-weight:bolder}
.vu{font-style:italic;font-weight:bold} .ttm{font-size:9pt}

Here's the CSS I'm using on This page:

.cb{background-color:#ffcc99}
.chd{background-color:#a58ddf;font-family:arial;font-
weight:bold;color:#ffffff}
.c1{background-color:#f3ecac}
.c2{background-color:#FFFFcc}
.cp{background-color:#33CCCC}
.va{color:#000099;font-style:italic;font-weight:bolder}
.vu{font-style:italic;font-weight:bold} .ttm{font-size:9pt}

--------------
Or, you can try a nice blend of Blue colors:

.cb{background-color:#9d9d9d}
.chd{background-color:#7a77a9;font-family:arial;font-
weight:bold;color:#ffffff}
.c1{background-color:#aed1e8}
.c2{background-color:#ddE4FF}
.cp{background-color:#85a5b4}
.va{color:#000099;font-style:italic;font-weight:bolder}
.vu{font-style:italic;font-weight:bold} .ttm{font-size:9pt}

_____________________
As explained before,
the above code would be placed in Advanced Forum CSS & Table-style Settings.
Then, scroll down to --CSS code (this is the actual code)
But, you must also place all the correct chd,c1 and c2 codes in the little boxes.
(Please refer to the photographs)

and, here's the explanation of each function:
.cb{background-color:#9d9d9d}
(mild halo around the comments box)
----------
.chd{background-color:#7a77a9;font-family:arial;font-
subject | author | date | msgs
(This line only appears once. leading the threads. soft Purple, here).
---
weight:bold;color:#ffffff}
(the actual color of text within subject | author | date | msgs) [This forum uses white text in subject line]
----------
.c1{background-color:#aed1e8}
The 1st line of each thread (such as "websites for Wallpapers")
----------
.c2{background-color:#ddE4FF}
(all the messages in the thread). aka "body"
----------
.cp{background-color:#85a5b4}
(the giant Comment Box. 'post a public new message')
----------
.va{color:#000099;font-style:italic;font-weight:bolder}
.vu{font-style:italic;font-weight:bold} .ttm{font-size:9pt}