diff --git a/args_manager.py b/args_manager.py
index 3c34d33..b5768ac 100644
--- a/args_manager.py
+++ b/args_manager.py
@@ -15,6 +15,8 @@ fcbh_cli.parser.add_argument("--enable-smart-memory", action="store_true",
                              help="Force loading models to vram when the unload can be avoided. "
                                   "Some Mac users may need this.")
 
+fcbh_cli.parser.add_argument("--theme", type=str, help="launches the UI with light or dark theme", default=None)
+
 fcbh_cli.parser.set_defaults(
     disable_cuda_malloc=True,
     auto_launch=True,
diff --git a/fooocus_version.py b/fooocus_version.py
index 3812afa..5e43afa 100644
--- a/fooocus_version.py
+++ b/fooocus_version.py
@@ -1 +1 @@
-version = '2.1.816'
+version = '2.1.817'
diff --git a/javascript/script.js b/javascript/script.js
index dc7f976..05a8c59 100644
--- a/javascript/script.js
+++ b/javascript/script.js
@@ -166,3 +166,10 @@ function uiElementInSight(el) {
 function playNotification() {
     gradioApp().querySelector('#audio_notification audio')?.play();
 }
+
+function set_theme(theme) {
+    var gradioURL = window.location.href;
+    if (!gradioURL.includes('?__theme=')) {
+        window.location.replace(gradioURL + '?__theme=' + theme);
+    }
+}
diff --git a/modules/ui_gradio_extensions.py b/modules/ui_gradio_extensions.py
index 0d0df97..cf9c792 100644
--- a/modules/ui_gradio_extensions.py
+++ b/modules/ui_gradio_extensions.py
@@ -38,6 +38,10 @@ def javascript_html():
     head += f'<script type="text/javascript" src="{edit_attention_js_path}"></script>\n'
     head += f'<script type="text/javascript" src="{viewer_js_path}"></script>\n'
     head += f'<script type="text/javascript" src="{image_viewer_js_path}"></script>\n'
+
+    if args_manager.args.theme:
+        head += f'<script type="text/javascript">set_theme(\"{args_manager.args.theme}\");</script>\n'
+    
     return head
 
 
diff --git a/update_log.md b/update_log.md
index a151adf..c322990 100644
--- a/update_log.md
+++ b/update_log.md
@@ -1,3 +1,7 @@
+# 2.1.817
+
+* support "--theme dark" and "--theme light".
+
 # 2.1.815
 
 * Multiple loras in preset.