Hey i found the solution for it. I installed the plugin called “Simple Custom CSS” in which you can override the Main.css file.
Or you can access your ftp server and change it on there.
This is the code of the footer
/* Colophon */
#colophon {
background: #100d0a;
color: #59544a;
padding: 10px;
}
#colophon a {
text-decoration: none;
color: #825e21;
}
#colophon .site-info {
float: left;
}
#colophon #footertext {
float: right;
}
now you can just reenter the code with the changed background code in the first part
/* Colophon */
#colophon {
background: #THISONE;