diff --git a/src/calibre/ebooks/pdf/html_writer.py b/src/calibre/ebooks/pdf/html_writer.py
index 904b287521..cf2e67a8c1 100644
--- a/src/calibre/ebooks/pdf/html_writer.py
+++ b/src/calibre/ebooks/pdf/html_writer.py
@@ -406,12 +406,17 @@ def create_margin_files(container):
 # Link handling  {{{
 def add_anchors_markup(root, uuid, anchors):
     body = last_tag(root)
-    div = body.makeelement(XHTML('div'), id=uuid, style='display:block; page-break-before: always; break-before: always')
+    div = body.makeelement(
+        XHTML('div'), id=uuid,
+        style='display:block; page-break-before: always; break-before: always;'
+    )
     body.append(div)
 
     def a(anchor):
         a = div.makeelement(
-            XHTML('a'), href='#' + anchor, style='white-space: pre; min-width: 10px; min-height: 10px; border: solid 1px')
+            XHTML('a'), href='#' + anchor,
+            style='white-space: pre; min-width: 10px; min-height: 10px; border: solid 1px;'
+        )
         a.text = a.tail = ' '
         div.append(a)
     tuple(map(a, anchors))