That only applies to *macro definitions* (i.e., variables). This is because $:/core/ui/PageTemplate contains this line:
<$importvariables filter="[[$:/core/ui/PageMacros]] [all[shadows+tiddlers]tag[$:/tags/Macro]!has[draft.of]]">
which references "...[tag[$/Tags/Macro]...", which explicitly pulls in macro definitions from tiddlers tagged that way.
To set global *styles*, there is a different tag to use: "$:/tags/Stylesheet"
To properly achieve your desired result:
1) Create a stylesheet tiddler (e.g., "MyStyles") and tag it with "$:/tags/Stylesheet". Note that this tiddler should NOT have the "<style>" and "</style> HTML syntax nor any other non-CSS content (i.e, NO <$select> widgets)... just the CSS declarations by themselves, like this:
.tc-tiddler-frame { background-color:{{$:/temp/tag2}}; }
body {font-family: {{$:/temp/tagfont}}}
p { font-size: {{$:/temp/tagfontsize}} }
Note: in your posted style definitions, you used ".background" as a classname. However, the actual classname to use to control the tiddler background color is .tc-tiddler-frame (which you correctly referenced in your original post)
Next, put the <$select> widgets into another tiddler (e.g., "SetMyStyles"), like this:
temp/tagfont'>
<option value='Arial'>Standard</option>
<option value='Times New Roman'>Times</option>
</$select>
Fontsize change:
<$select tiddler='$:/temp/tagfontsize'>
<option value='12px'>sehr klein</option>
<option value='16px'>klein</option>
<option value='20px'>mittel</option>
<option value='25px'>groß</option>
</$select>
When you view that tiddler and make your selections from the droplist controls that are shown, your choices are stored in "$:/temp/..." tiddlers containing the desired CSS attribute values, which are then automatically referenced from the stylesheet you created. Note that these choices will persist even when the tiddler containing the <$select> widgets is not displayed since the values you choose are stored separately.
Q.E.D.
enjoy,
-e
Eric Shulman
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