diff --git a/core/themes/classy/css/components/book-navigation.css b/core/themes/classy/css/components/book-navigation.css
index c300e4d..fe02a0f 100644
--- a/core/themes/classy/css/components/book-navigation.css
+++ b/core/themes/classy/css/components/book-navigation.css
@@ -18,7 +18,7 @@
 }
 .book-pager__item--previous {
   text-align: left; /* LTR */
-  width: 45%;
+  width: 43%;
 }
 [dir="rtl"] .book-pager__item--previous {
   float: right;