diff --git a/docs/conf.py b/docs/conf.py
index 5be32fd5..85aacdef 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -18,6 +18,7 @@
 
 # -- Non stdlib imports --------------------------------------------------------
 from sunkit_instruments import __version__  # NOQA
+from sunpy_sphinx_theme import PNG_ICON  # NOQA
 
 # -- Project information -------------------------------------------------------
 project = "sunkit_instruments"
@@ -85,7 +86,7 @@
 default_role = "obj"
 
 # -- Options for HTML output ---------------------------------------------------
-from sunpy_sphinx_theme.conf import *  # NOQA
+html_theme = "sunpy"
 
 # -- Graphviz Output ------------------------------------------------------------
 graphviz_output_format = "svg"
@@ -105,8 +106,7 @@
     "examples_dirs": os.path.join("..", "examples"),
     "gallery_dirs": os.path.join("generated", "gallery"),
     "matplotlib_animations": True,
-    # Comes from the theme.
-    "default_thumb_file": png_icon,
+    "default_thumb_file": PNG_ICON,
     "abort_on_example_error": False,
     "plot_gallery": "True",
     "remove_config_comments": True,