Make content margin configurable for narrow sections

REDMINE-20989

Author: tf

entry_types/scrolled/package/src/frontend/Section.module.css

@@ -11,6 +11,9 @@
   --section-max-width:
     var(--theme-section-max-width);
 
+  --content-margin-fraction: var(--theme-content-margin-fraction, 0.08);
+  --content-margin: var(--theme-content-margin, calc(var(--content-margin-fraction) * 100%));
+
   --two-column-inline-content-max-width:
     var(--theme-two-column-inline-content-max-width);
   --two-column-inline-lg-content-max-width:
@@ -45,6 +48,11 @@
   --section-max-width:
     var(--theme-narrow-section-max-width);
 
+  --content-margin-fraction:
+    var(--theme-narrow-section-content-margin-fraction, var(--theme-content-margin-fraction, 0.08));
+  --content-margin:
+    var(--theme-narrow-section-content-margin, calc(var(--content-margin-fraction) * 100%));
+
   --two-column-inline-content-max-width:
     var(--theme-narrow-section-two-column-inline-content-max-width);
   --two-column-inline-lg-content-max-width:

entry_types/scrolled/package/src/frontend/layouts/Center.module.css

@@ -1,7 +1,4 @@
 .outer {
-  --content-margin-fraction: var(--theme-content-margin-fraction, 0.08);
-  --content-margin: var(--theme-content-margin,
-                        calc(var(--content-margin-fraction) * 100%));
   padding-left: var(--content-margin);
   padding-right: var(--content-margin);
   margin-left: auto;

entry_types/scrolled/package/src/frontend/layouts/TwoColumn.module.css

@@ -2,8 +2,6 @@
 }
 
 .group {
-  --content-margin-fraction: var(--theme-content-margin-fraction, 0.08);
-  --content-margin: var(--theme-content-margin, calc(var(--content-margin-fraction) * 100%));
   padding-left: var(--content-margin);
   padding-right: var(--content-margin);
   margin-left: auto;