Upload app.py

app.py

@@ -30,6 +30,38 @@ st.set_page_config(page_title="智答 AI 助手", page_icon="🤖", layout="wide
 def _get_custom_css():
     return """
         <style>
+            /* 暗色模式适配 */
+            @media (prefers-color-scheme: dark) {
+                .main-title {
+                    background: #0e1117 !important;
+                }
+                [data-testid="stChatInput"] {
+                    background: #0e1117 !important;
+                }
+                /* 暗色模式下快捷问题按钮颜色 */
+                .block-container:has(.welcome-marker) [data-testid="stBaseButton-secondary"]:hover {
+                    background: rgba(255,255,255,0.1) !important;
+                }
+                /* 暗色模式下工具栏按钮 hover */
+                .stMainBlockContainer > div > div > div:has(.toolbar-marker) button:hover {
+                    background: rgba(255,255,255,0.1) !important;
+                }
+            }
+            /* Streamlit 暗色主题适配 */
+            [data-theme="dark"] .main-title,
+            .stApp[data-theme="dark"] .main-title {
+                background: #0e1117 !important;
+            }
+            [data-theme="dark"] [data-testid="stChatInput"],
+            .stApp[data-theme="dark"] [data-testid="stChatInput"] {
+                background: #0e1117 !important;
+            }
+            
+            /* 隐藏工具栏标记 */
+            .toolbar-marker {
+                display: none !important;
+            }
+            
             [data-testid="stSidebarContent"] { padding-top: 1.5rem !important; }
             [data-testid="stVerticalBlock"] > div { gap: 0.2rem !important; }
             /* 聊天消息间距控制 */
@@ -143,7 +175,7 @@ def _get_custom_css():
                 left: 0 !important;
                 right: 0 !important;
                 z-index: 9999 !important;
-                background: white !important;
+                background: var(--background-color, white) !important;
                 padding: 0.3rem 1rem !important;
             }
             
@@ -156,7 +188,7 @@ def _get_custom_css():
                 width: calc(100% - 2rem) !important;
                 max-width: 730px !important;
                 z-index: 9999 !important;
-                background: white !important;
+                background: var(--background-color, white) !important;
             }
             /* 搜索框聚焦时去掉红色边框 */
             [data-testid="stChatInput"] textarea:focus,
@@ -166,8 +198,8 @@ def _get_custom_css():
                 box-shadow: none !important;
             }
             
-            /* 底部工具栏固定在搜索框下方 */
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) {
+            /* 底部工具栏固定在搜索框下方 - 使用 toolbar-marker 精确定位 */
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) {
                 position: fixed !important;
                 bottom: 0.3rem !important;
                 left: 50% !important;
@@ -176,17 +208,17 @@ def _get_custom_css():
                 max-width: 730px !important;
                 z-index: 9998 !important;
             }
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stHorizontalBlock"] {
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stHorizontalBlock"] {
                 display: flex !important;
                 flex-wrap: nowrap !important;
                 gap: 0.5rem !important;
             }
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stHorizontalBlock"] > div {
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stHorizontalBlock"] > div {
                 flex: 1 !important;
                 min-width: 0 !important;
             }
             /* 确保底部工具栏按钮占满容器宽度 */
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stHorizontalBlock"] button {
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stHorizontalBlock"] button {
                 width: 100% !important;
             }
             /* popover 向上展开 */
@@ -197,21 +229,21 @@ def _get_custom_css():
             }
             
             /* 底部工具栏按钮：无边框风格，统一颜色 */
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) button,
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stPopover"] > div:first-child {
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) button,
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stPopover"] > div:first-child {
                 background: transparent !important;
                 border: none !important;
                 box-shadow: none !important;
                 color: #666 !important;
             }
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) button:hover,
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stPopover"] > div:first-child:hover {
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) button:hover,
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stPopover"] > div:first-child:hover {
                 background: rgba(0,0,0,0.05) !important;
             }
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) button p,
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) button span,
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stMarkdownContainer"] p,
-            .stMainBlockContainer > div > div > div:has([data-testid="stPopover"]) [data-testid="stPopover"] p {
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) button p,
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) button span,
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stMarkdownContainer"] p,
+            .stMainBlockContainer > div > div > div:has(.toolbar-marker) [data-testid="stPopover"] p {
                 color: #666 !important;
             }
             
@@ -951,6 +983,12 @@ SYSTEM_PROMPT_WEB = (
     "回答要简洁实用，注明信息来源。"
 )
 
+SYSTEM_PROMPT_DIRECT = (
+    "你是一个智能AI助手，请直接根据你的知识回答用户问题。"
+    "回答要准确、有条理、简洁实用。"
+    "如果不确定某些信息，请诚实说明。"
+)
+
 
 def web_search(query):
     if not TAVILY_KEY:
@@ -1462,7 +1500,7 @@ def search_local(query, top_k, threshold):
 # =========================
 # 9. LLM 回答逻辑
 # =========================
-def llm_answer(query, context_docs, selected_display_name, web_enabled):
+def llm_answer(query, context_docs, selected_display_name, web_enabled, is_guest=False):
     all_context = ""
     curr_time = datetime.now().strftime("%Y-%m-%d %H:%M")
 
@@ -1472,10 +1510,13 @@ def llm_answer(query, context_docs, selected_display_name, web_enabled):
         all_context = f"【互联网搜索结果】：\n{search_res}"
         prompt_content = f"当前时间：{curr_time}\n\n{all_context[:6500]}\n\n用户问题：{query}"
         system_prompt = SYSTEM_PROMPT_WEB
+    elif is_guest or not context_docs:
+        # 直接回答模式（游客不联网 或 登录用户无知识库资料）
+        prompt_content = f"当前时间：{curr_time}\n\n用户问题：{query}"
+        system_prompt = SYSTEM_PROMPT_DIRECT
     else:
         # 知识库模式：用知识库资料
-        if context_docs:
-            all_context = "【知识库资料】：\n" + "\n".join(context_docs)
+        all_context = "【知识库资料】：\n" + "\n".join(context_docs)
         prompt_content = f"当前时间：{curr_time}\n\n参考资料：\n{all_context[:6500]}\n\n用户问题：{query}"
         system_prompt = SYSTEM_PROMPT
 
@@ -1677,7 +1718,7 @@ def _chat_fragment():
 
                 try:
                     full_response = response_container.write_stream(
-                        llm_answer(q, relevant_docs, _model_name, _web_on)
+                        llm_answer(q, relevant_docs, _model_name, _web_on, IS_GUEST)
                     )
                     meta_info = st.session_state.get("last_meta", "")
                     # meta 拼进 response_container，不创建独立DOM元素
@@ -1701,6 +1742,8 @@ def _chat_fragment():
 # =========================
 @st.fragment
 def _toolbar_fragment():
+    # 添加工具栏标记，用于 CSS 精确定位
+    st.markdown('<div class="toolbar-marker"></div>', unsafe_allow_html=True)
     _current_model = st.session_state.get("sel_model", list(model_mapping.keys())[0])
     _web_status = st.session_state.get("sel_web", True)
     _model_short = _current_model.split("(")[0].strip()