Update app.py

app.py

@@ -52,7 +52,9 @@ def run_script(url: str, height: int, width: int, check_b,check_h):
             driver.get(url)
             html=driver.page_source
             #print (driver.html)
-            driver.execute_script("arguments[0].theme='gab-black';")
+            page = driver.find_element(By.TAG_NAME, "html")
+            
+            driver.execute_script("arguments[0].theme='gab-black';",page)
             
             driver.implicitly_wait(30)
             driver.set_window_size(int(width), int(height))