Your CSS is mostly right, but you've got the identifiers wrong.
When the "right sidebar only" configuration is used, the classes responsible for stylizing the page are
right_sidebar[/m] (sidebar) and [m]left_page (content) as defined in main.php circa line 150. Thus the bare CSS to achieve the effect would be something like this:
div.dokuwiki div.left_page {
float: left;
/* these two values you must adjust by taking the full width of the template:
max-width must be the full width (probably 1000px or something) minus the 200 px that you want, minus margins
min-width should be a percentage
*/
max-width: 800%;
min-width: 60%;
margin-right: 0;
}
div.right_sidebar {
float: right;
width: 200px;
margin-left: 0;
}
; and you'll probably have to add
!important to some of the clauses. Take note that because both panels are floated and the only way to specify that the left one should "fill all available space" in CSS is by specifying a width (as the right one is not using a percentage), the resulting design will look bad in some unmaximized windows.
Also remember to
clear both caches when testing this kind of modifications.