Fix voice selector white screen on dark mobile UI.

Replace Dropdown with styled Radio and add dark-theme CSS for select lists.

Co-authored-by: Cursor <cursoragent@cursor.com>

app.py

@@ -489,6 +489,70 @@ gradio-app,
     border: 1px solid #64748b !important;
 }
 
+/* 音色选择 Radio（避免 Dropdown 在深色/手机端白底白字） */
+.gradio-container .voice-radio fieldset {
+    border: 1px solid #374151 !important;
+    border-radius: 10px !important;
+    background: #111827 !important;
+    padding: 10px 12px !important;
+}
+.gradio-container .voice-radio label {
+    display: flex !important;
+    align-items: center !important;
+    gap: 10px !important;
+    padding: 10px 12px !important;
+    margin: 6px 0 !important;
+    border-radius: 8px !important;
+    border: 1px solid #374151 !important;
+    background: #1a2332 !important;
+    color: #e5e7eb !important;
+    font-size: 0.92rem !important;
+    cursor: pointer !important;
+}
+.gradio-container .voice-radio label:hover {
+    border-color: #3b82f6 !important;
+    background: #1e293b !important;
+}
+.gradio-container .voice-radio label.selected {
+    border-color: #3b82f6 !important;
+    background: #1e3a5f !important;
+    color: #ffffff !important;
+    font-weight: 600 !important;
+}
+.gradio-container .voice-radio input[type="radio"] {
+    accent-color: #3b82f6 !important;
+    width: 18px !important;
+    height: 18px !important;
+    flex-shrink: 0 !important;
+}
+
+/* Dropdown 兜底（其他下拉组件深色化） */
+.gradio-container .gradio-dropdown input,
+.gradio-container .dropdown input,
+.gradio-container select {
+    background: #1a2332 !important;
+    color: #ffffff !important;
+    border: 1px solid #4b5563 !important;
+}
+.gradio-container ul.options,
+.gradio-container .gradio-dropdown ul,
+.gradio-container [role="listbox"] {
+    background: #1e293b !important;
+    border: 1px solid #4b5563 !important;
+    color: #e5e7eb !important;
+}
+.gradio-container ul.options li,
+.gradio-container [role="option"] {
+    color: #e5e7eb !important;
+    background: #1e293b !important;
+}
+.gradio-container ul.options li:hover,
+.gradio-container ul.options li.selected,
+.gradio-container [role="option"][aria-selected="true"] {
+    background: #2563eb !important;
+    color: #ffffff !important;
+}
+
 /* 输入框下方 info 提示文字 */
 .gradio-container .hint,
 .gradio-container .info,
@@ -954,11 +1018,12 @@ def build_app() -> gr.Blocks:
                             "> 全部在 **本机显卡** 运行，无需微软/讯飞 API。"
                             "可选「我的锁定音色」或预设男/女声；合成前会自动清洗 Markdown。"
                         )
-                        tts_voice = gr.Dropdown(
+                        tts_voice = gr.Radio(
                             label="配音音色（本地 ChatTTS）",
                             choices=voice_choice_labels(),
                             value=_default_voice_label(),
                             info="预设音色需先在服务器执行 bash scripts/generate_voice_presets.sh",
+                            elem_classes=["voice-radio"],
                         )
                         polished_text = gr.Textbox(
                             label="润色配音稿（可编辑，支持含 Markdown，合成时自动清洗）",
@@ -998,10 +1063,11 @@ def build_app() -> gr.Blocks:
                     label="跳过 Gemma4 润色（仅测试 TTS）",
                     value=False,
                 )
-                pipe_voice = gr.Dropdown(
+                pipe_voice = gr.Radio(
                     label="配音音色（本地 ChatTTS）",
                     choices=voice_choice_labels(),
                     value=_default_voice_label(),
+                    elem_classes=["voice-radio"],
                 )
                 pipeline_btn = gr.Button("▶ 启动全流程", variant="primary", size="lg")
                 pipeline_log = gr.Textbox(label="流水线日志", lines=6, interactive=False)