+After performing the initial transform, ⛩️📰 书社 will match the root
+ node of the result in the following modes to fill in areas of the
+ wrapper :—
+
+- **`书社:header`:**
+ The result of matching in this mode is prepended into the
+ `<html:body>` of the output (before the transformation result).
+
+- **`书社:footer`:**
+ The result of matching in this mode is appended into the
+ `<html:body>` of the output (after the transformation result).
+
+- **`书社:metadata`:**
+ The result of matching in this mode is inserted into the
+ `<html:head>` of the output.
+
+In addition to being called with the transform result, each of these
+ modes will additionally be called with a `<xslt:include>` element
+ corresponding to each transform.
+If a transform has a `<书社:id>` top‐level element whose value is an
+ i·r·i, its `<xslt:include>` element will have a corresponding
+ `@书社:id` attribute.
+This mechanism can be used to allow transforms to insert content
+ without matching any elements in the result; for example, the
+ following transform adds a link to a stylesheet to the `<html:head>`
+ of every page :—
+
+```xml
+<?xml version="1.0"?>
+<transform
+ xmlns="http://www.w3.org/1999/XSL/Transform"
+ xmlns:html="http://www.w3.org/1999/xhtml"
+ xmlns:xslt="http://www.w3.org/1999/XSL/Transform"
+ xmlns:书社="urn:fdc:ladys.computer:20231231:Shu1She4"
+ exclude-result-prefixes="书社"
+ version="1.0"
+>
+ <书社:id>example:add-stylesheet-links.xslt</书社:id>
+ <template match="xslt:include[@书社:id='example:add-stylesheet-links.xslt']" mode="书社:metadata">
+ <html:link rel="stylesheet" type="text/css" href="/style.css"/>
+ </template>
+</transform>
+```
+
+Output wrapping can be entirely disabled by adding a
+ `@书社:disable-output-wrapping` attribute to the top‐level element in
+ the result tree.
+This attribute will also prevent wrapping non‐H·T·M·L embeds with an
+ `<html:div>`.
+
+## Applying Attributes
+
+The `<书社:apply-attributes>` element will apply any attributes on the
+ element to the element(s) it wraps.
+It is especially useful in combination with embeds.
+
+The `<书社:apply-attributes-to-root>` element will apply any attributes
+ on the element to the root node of the final transformation result.
+It is especially useful in combination with output wrapping.
+
+In both cases, attributes from various sources are combined with
+ white·space between them.
+Attribute application takes place after all ordinary transforms have
+ completed.
+
+Both elements ignore attributes in the `xml:` namespace, except for
+ `@xml:lang`, which ignores all but the first definition (including
+ any already present on the root element).
+On H·T·M·L and S·V·G elements, `@lang` has the same behaviour as
+ `@xml:lang`.