diff --git a/doc/build/.keep b/doc/build/.keep
deleted file mode 100644
index e69de29..0000000
diff --git a/doc/source/conf.py b/doc/source/conf.py
index 0a77970..e03ac20 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -124,7 +124,7 @@
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+# html_static_path = ['_static']
 
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.
diff --git a/tox.ini b/tox.ini
index 9d23496..2ed76c3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -18,3 +18,9 @@ skip_missing_interpreters = true
 usedevelop=true
 deps=-rrequirements-testing.txt
 commands = py.test --verbose --verbose --cov xmodem {posargs}
+
+[testenv:build_sphinx]
+# build html documentation
+deps=-rrequirements-docs.txt
+basepython = python3.11
+commands={envbindir}/python setup.py build_sphinx
diff --git a/xmodem/__init__.py b/xmodem/__init__.py
index 9dcf613..918835e 100644
--- a/xmodem/__init__.py
+++ b/xmodem/__init__.py
@@ -137,18 +137,20 @@ class XMODEM(object):
     XMODEM Protocol handler, expects two callables which encapsulate the read
         and write operations on the underlying stream.
 
-    Example functions for reading and writing to a serial line using `pyserial <http://pyserial.sourceforge.net/>`_::
-
-    >>> import serial
-    >>> from xmodem import XMODEM
-    >>> ser = serial.Serial('/dev/ttyUSB0', timeout=0) # or whatever you need
-    >>> def getc(size, timeout=1):
-    ...     return ser.read(size) or None
-    ...
-    >>> def putc(data, timeout=1):
-    ...     return ser.write(data) or None
-    ...
-    >>> modem = XMODEM(getc, putc)
+    Example functions for reading and writing to a serial line using `pyserial <http://pyserial.sourceforge.net/>`_,
+
+    .. code-block:: python
+
+        import serial
+        from xmodem import XMODEM
+        ser = serial.Serial('/dev/ttyUSB0', timeout=0) # or whatever you need
+        def getc(size, timeout=1):
+            return ser.read(size) or None
+
+        def putc(data, timeout=1):
+            return ser.write(data) or None
+
+        modem = XMODEM(getc, putc)
 
     :param getc: Function to retrieve bytes from a stream. The function takes
         the number of bytes to read from the stream and a timeout in seconds as