MkDocs's media url shouldn't be hardcode with media_url = 'http://localhost:8000' + media_url
In file `readthedocs.org/readthedocs/doc_builder/backends/mkdocs.py`:

``` python
55        # Set mkdocs config values
56
57        media_url = getattr(settings, 'MEDIA_URL', 'https://media.readthedocs.org')
58
59        # Mkdocs needs a full domain here because it tries to link to local media files
60        if not media_url.startswith('http'):
61            media_url = 'http://localhost:8000' + media_url
```

Can u please to replace it with `SITE_URL` as the follows:

``` python
59        # Mkdocs needs a full domain here because it tries to link to local media files
60        if not media_url.startswith('http'):
61            media_url = getattr(settings, 'SITE_URL', None) + media_url
```

diff --git a/readthedocs/doc_builder/backends/mkdocs.py b/readthedocs/doc_builder/backends/mkdocs.py
index 4833c99a6..e1ab80dba 100644
--- a/readthedocs/doc_builder/backends/mkdocs.py
+++ b/readthedocs/doc_builder/backends/mkdocs.py
@@ -58,7 +58,8 @@ class BaseMkdocs(BaseBuilder):
 
         # Mkdocs needs a full domain here because it tries to link to local media files
         if not media_url.startswith('http'):
-            media_url = 'http://localhost:8000' + media_url
+            domain = getattr(settings, 'PRODUCTION_DOMAIN')
+            media_url = 'http://{}/{}'.format(domain, media_url)
 
         if 'extra_javascript' in user_config:
             user_config['extra_javascript'].append('readthedocs-data.js')
['readthedocs/doc_builder/backends/mkdocs.py']