diff --git a/src/calibre/ebooks/conversion/plugins/htmlz_output.py b/src/calibre/ebooks/conversion/plugins/htmlz_output.py
index ac7a6d4231..0f5d9b5333 100644
--- a/src/calibre/ebooks/conversion/plugins/htmlz_output.py
+++ b/src/calibre/ebooks/conversion/plugins/htmlz_output.py
@@ -89,7 +89,7 @@ class HTMLZOutput(OutputFormatPlugin):
# CSS
if opts.htmlz_css_type == 'class' and opts.htmlz_class_style == 'external':
with open(os.path.join(tdir, u'style.css'), 'wb') as tf:
- tf.write(htmlizer.get_css(oeb_book))
+ tf.write(htmlizer.get_css(oeb_book).encode('utf-8'))
# Images
images = htmlizer.images
diff --git a/src/calibre/ebooks/htmlz/oeb2html.py b/src/calibre/ebooks/htmlz/oeb2html.py
index 0fcf6a67d4..0470109d6d 100644
--- a/src/calibre/ebooks/htmlz/oeb2html.py
+++ b/src/calibre/ebooks/htmlz/oeb2html.py
@@ -20,7 +20,7 @@ from calibre.ebooks.oeb.base import (
XHTML, XHTML_NS, SVG_NS, barename, namespace, OEB_IMAGES, XLINK, rewrite_links, urlnormalize)
from calibre.ebooks.oeb.stylizer import Stylizer
from calibre.utils.logging import default_log
-from polyglot.builtins import unicode_type, string_or_bytes, as_bytes
+from polyglot.builtins import unicode_type, string_or_bytes, as_unicode
from polyglot.urllib import urldefrag
SELF_CLOSING_TAGS = {'area', 'base', 'basefont', 'br', 'hr', 'input', 'img', 'link', 'meta'}
@@ -131,10 +131,10 @@ class OEB2HTML(object):
el.attrib['id'] = self.get_link_id(page.href, el.attrib['id'])[1:]
def get_css(self, oeb_book):
- css = b''
+ css = ''
for item in oeb_book.manifest:
if item.media_type == 'text/css':
- css += as_bytes(item.data.cssText) + b'\n\n'
+ css += as_unicode(item.data.cssText) + '\n\n'
return css
def prepare_string_for_html(self, raw):
@@ -337,9 +337,9 @@ class OEB2HTMLClassCSSizer(OEB2HTML):
output += self.dump_text(item.data.find(XHTML('body')), stylizer, item)
output.append('\n\n')
if self.opts.htmlz_class_style == 'external':
- css = u''
+ css = ''
else:
- css = u''
+ css = ''
title = u'%s' % prepare_string_for_xml(self.book_title)
output = [u''] + \
[css] + [title, u''] + output + [u'']