diff --git a/core/modules/book/book-navigation.tpl.php b/core/modules/book/book-navigation.tpl.php
index 5d8e9aa..0efe9aa 100644
--- a/core/modules/book/book-navigation.tpl.php
+++ b/core/modules/book/book-navigation.tpl.php
@@ -30,21 +30,21 @@
  */
 ?>
 <?php if ($tree || $has_links): ?>
-  <div id="book-navigation-<?php print $book_id; ?>" class="book-navigation">
+  <div class="book-navigation">
     <?php print $tree; ?>
 
     <?php if ($has_links): ?>
-    <div class="page-links clearfix">
+    <ul class="pager clearfix">
       <?php if ($prev_url): ?>
-        <a href="<?php print $prev_url; ?>" class="page-previous" title="<?php print t('Go to previous page'); ?>"><?php print t('‹ ') . $prev_title; ?></a>
+        <li class="page-previous"><a href="<?php print $prev_url; ?>" title="<?php print t('Go to previous page'); ?>"><?php print t('‹ ') . $prev_title; ?></a></li>
       <?php endif; ?>
       <?php if ($parent_url): ?>
-        <a href="<?php print $parent_url; ?>" class="page-up" title="<?php print t('Go to parent page'); ?>"><?php print t('up'); ?></a>
+        <li class="page-up"><a href="<?php print $parent_url; ?>" title="<?php print t('Go to parent page'); ?>"><?php print t('up'); ?></a></li>
       <?php endif; ?>
       <?php if ($next_url): ?>
-        <a href="<?php print $next_url; ?>" class="page-next" title="<?php print t('Go to next page'); ?>"><?php print $next_title . t(' ›'); ?></a>
+        <li class="page-next"><a href="<?php print $next_url; ?>" title="<?php print t('Go to next page'); ?>"><?php print $next_title . t(' ›'); ?></a></li>
       <?php endif; ?>
-    </div>
+    </ul>
     <?php endif; ?>
 
   </div>
diff --git a/core/modules/book/book-rtl.css b/core/modules/book/book-rtl.css
deleted file mode 100644
index f3a84c2..0000000
--- a/core/modules/book/book-rtl.css
+++ /dev/null
@@ -1,11 +0,0 @@
-
-.book-navigation .menu {
-  padding: 1em 3em 0 0;
-}
-
-.book-navigation .page-previous {
-  float: right;
-}
-.book-navigation .page-up {
-  float: right;
-}
diff --git a/core/modules/book/book.css b/core/modules/book/book.css
deleted file mode 100644
index 3348c0f..0000000
--- a/core/modules/book/book.css
+++ /dev/null
@@ -1,51 +0,0 @@
-
-.book-navigation .menu {
-  border-top: 1px solid #888;
-  padding: 1em 0 0 3em; /* LTR */
-}
-.book-navigation .page-links {
-  border-top: 1px solid #888;
-  border-bottom: 1px solid #888;
-  text-align: center;
-  padding: 0.5em;
-}
-.book-navigation .page-previous {
-  text-align: left;
-  width: 42%;
-  display: block;
-  float: left; /* LTR */
-}
-.book-navigation .page-up {
-  margin: 0 5%;
-  width: 4%;
-  display: block;
-  float: left; /* LTR */
-}
-.book-navigation .page-next {
-  text-align: right;
-  width: 42%;
-  display: block;
-  float: right;
-}
-.book-outline-form .form-item {
-  margin-top: 0;
-  margin-bottom: 0;
-}
-html.js #edit-book-pick-book {
-  display: none;
-}
-.form-item-book-bid .description {
-  clear: both;
-}
-#book-admin-edit select {
-  margin-right: 24px;
-}
-#book-admin-edit select.progress-disabled {
-  margin-right: 0;
-}
-#book-admin-edit tr.ajax-new-content {
-  background-color: #ffd;
-}
-#book-admin-edit .form-item {
-  float: left;
-}
diff --git a/core/modules/book/book.info b/core/modules/book/book.info
index 0f4d2b1..15984ad 100644
--- a/core/modules/book/book.info
+++ b/core/modules/book/book.info
@@ -5,4 +5,4 @@ version = VERSION
 core = 8.x
 files[] = book.test
 configure = admin/content/book/settings
-stylesheets[all][] = book.css
+stylesheets[all][] = book.theme.css
diff --git a/core/modules/book/book.module b/core/modules/book/book.module
index de09034..496457e 100644
--- a/core/modules/book/book.module
+++ b/core/modules/book/book.module
@@ -408,6 +408,9 @@ function book_form_node_form_alter(&$form, &$form_state, $form_id) {
       '#value' => t('Change book (update list of parents)'),
       '#submit' => array('book_pick_book_nojs_submit'),
       '#weight' => 20,
+      '#attached' => array(
+        'css' => array(drupal_get_path('module', 'book') . '/book.base.css'),
+      ),
     );
   }
 }
diff --git a/core/modules/book/book.test b/core/modules/book/book.test
index 6c351b8..e069aac 100644
--- a/core/modules/book/book.test
+++ b/core/modules/book/book.test
@@ -137,15 +137,16 @@ class BookTestCase extends DrupalWebTestCase {
 
     // Check previous, up, and next links.
     if ($previous) {
-      $this->assertRaw(l('‹ ' . $previous->title, 'node/' . $previous->nid, array('attributes' => array('class' => array('page-previous'), 'title' => t('Go to previous page')))), t('Previous page link found.'));
+      $this->assertRaw('<li class="page-previous">' . l('‹ ' . $previous->title, 'node/' . $previous->nid, array('attributes' => array('title' => t('Go to previous page')))), t('Previous page link found.') . '</li>');
     }
 
     if ($up) {
-      $this->assertRaw(l('up', 'node/' . $up->nid, array('attributes' => array('class' => array('page-up'), 'title' => t('Go to parent page')))), t('Up page link found.'));
+      $this->assertRaw('<li class="page-up">' . l('up', 'node/' . $up->nid, array('attributes' => array('title' => t('Go to parent page')))), t('Up page link found.') . '</li>');
     }
 
     if ($next) {
-      $this->assertRaw(l($next->title . ' ›', 'node/' . $next->nid, array('attributes' => array('class' => array('page-next'), 'title' => t('Go to next page')))), t('Next page link found.'));
+//      $this->assertRaw(l($next->title . ' ›', 'node/' . $next->nid, array('attributes' => array('class' => array('page-next'), 'title' => t('Go to next page')))), t('Next page link found.'));
+      $this->assertRaw('<li class="page-next">' . l($next->title . ' ›', 'node/' . $next->nid, array('attributes' => array('title' => t('Go to next page')))), t('Next page link found.') . '</li>');
     }
 
     // Compute the expected breadcrumb.
@@ -183,8 +184,9 @@ class BookTestCase extends DrupalWebTestCase {
     foreach ($nodes as $node) {
       $outline .= '(node\/' . $node->nid . ')(.*?)(' . $node->title . ')(.*?)';
     }
-
-    return '/<div id="book-navigation-' . $this->book->nid . '"(.*?)<ul(.*?)' . $outline . '<\/ul>/s';
+    $pattern = '/<div class="book-navigation"(.*?)<ul(.*?)' . $outline . '<\/ul>/s';
+    $this->verbose("<pre>$pattern</pre>");   // @todo remove this line
+    return $pattern;
   }
 
   /**