/* ========== 移动端响应式 ========== */
        @media (max-width: 768px) {
            :root {
                --chat-max-width: 100%;
            }

            body {
                flex-direction: column;
            }

            /* 右侧搜索侧边栏在移动端 */
            .search-sidebar {
                position: fixed;
                top: 0;
                right: 0;
                width: 300px;
                max-width: 85vw;
                height: 100vh;
                z-index: 200;
                transform: translateX(100%);
                transition: transform 0.3s ease;
                box-shadow: -2px 0 20px rgba(0,0,0,0.15);
                border-left: 1px solid var(--border-color);
            }
            .search-sidebar:not(.hidden) {
                transform: translateX(0);
                width: 300px;
                opacity: 1;
            }
            .search-sidebar.hidden {
                transform: translateX(100%);
                width: 300px;
                opacity: 0;
            }

            /* 侧边栏：移动端默认隐藏，滑出覆盖 */
            .sidebar {
                position: fixed;
                top: 0;
                left: 0;
                width: 280px;
                max-width: 85vw;
                height: 100dvh;
                padding-bottom: calc(16px + env(safe-area-inset-bottom, 0px));
                z-index: 200;
                transform: translateX(-100%);
                transition: transform 0.3s ease;
                box-shadow: 2px 0 20px rgba(0,0,0,0.15);
                border-right: 1px solid var(--border-color);
            }
            .sidebar:not(.hidden) {
                transform: translateX(0);
            }
            .sidebar.hidden {
                transform: translateX(-100%);
                width: 280px;
                max-width: 85vw;
                padding: 24px 16px calc(16px + env(safe-area-inset-bottom, 0px));
                opacity: 1;
            }

            /* 侧边栏遮罩 */
            .sidebar-mobile-overlay {
                position: fixed;
                top: 0; left: 0; right: 0; bottom: 0;
                background: rgba(0,0,0,0.35);
                z-index: 199;
                display: none;
            }
            .sidebar-mobile-overlay.show {
                display: block;
            }

            /* 主内容区 */
            .main-content {
                width: 100%;
                flex: 1;
                min-height: 0;
                overflow: hidden;
                display: flex;
                flex-direction: column;
            }

            .top-nav {
                padding: 10px 14px;
                min-height: 50px;
            }
            .nav-right-actions {
                max-width: 100%;
                overflow-x: auto;
                scrollbar-width: none !important;
            }
            .nav-right-actions::-webkit-scrollbar {
                display: none !important;
            }
            .sidebar-toggle-btn {
                display: block;
                opacity: 0.7;
            }

            /* 欢迎页面 */
            .welcome-screen {
                margin-top: 15vh;
            }
            .welcome-screen h1 {
                font-size: 26px;
            }
            .welcome-screen p {
                font-size: 13px;
            }
            .empty-chat .chat-container {
                flex: 1 1 0;
                justify-content: flex-end;
                padding-top: 0;
                padding-bottom: 10px;
            }
            .empty-chat .welcome-screen {
                margin-top: 0;
            }
            .empty-chat .input-area {
                flex: 1 1 0;
                align-items: flex-start;
                padding-top: 0;
                padding-bottom: calc(24px + env(safe-area-inset-bottom, 0px));
            }

            /* 聊天区域 */
            .chat-container {
                padding: 12px 12px;
                min-height: 0;
            }
            .chat-inner {
                max-width: 100%;
            }

            /* 消息 */
            .message.user {
                max-width: 90%;
            }
            .message.user .message-content {
                padding: 10px 16px;
                font-size: 14px;
            }
            .message.assistant .message-content {
                font-size: 14px;
            }

            /* 思考过程 */
            .thought-process {
                font-size: 12px;
            }

            /* 消息锚点：移动端隐藏 */
            .message-anchors {
                display: none !important;
            }

            /* 输入区域 */
            .input-area {
                padding: 8px 10px calc(12px + env(safe-area-inset-bottom, 0px)) 10px;
            }
            .input-pill {
                max-width: 100%;
                padding: 8px 10px 8px 14px;
                gap: 8px;
                border-radius: 24px;
            }
            .input-pill textarea {
                font-size: 15px;
            }
            .pill-bottom {
                flex-wrap: nowrap;
                gap: 6px;
            }
            .pill-toolrail {
                gap: 6px;
                flex-wrap: nowrap;
            }
            .model-switcher,
            .thinking-switcher,
            .web-tools-switcher,
            .search-switcher {
                transform: none;
                flex-shrink: 0;
            }
            .web-tools-switcher,
            .search-switcher {
                overflow-x: visible;
            }
            .pill-toolrail::-webkit-scrollbar {
                display: none !important;
            }
            .action-group {
                margin-left: auto;
            }
            .model-info {
                font-size: 12px;
            }
            .send-btn {
                width: 30px;
                height: 30px;
            }

            /* 预设标签 */
            .preset-tags-area {
                padding: 0 10px;
            }
            .preset-tags-row {
                max-width: 100%;
                gap: 6px;
            }
            .preset-tag {
                padding: 4px 10px;
                font-size: 12px;
            }

            /* 图片预览：在输入框内部，无需额外 padding */
            .user-image {
                max-width: 150px;
                max-height: 150px;
            }

            /* Modal 弹窗 */
            .modal {
                width: 94vw;
                max-width: 94vw;
                padding: 18px;
                border-radius: 14px;
                gap: 12px;
                margin: 0 3vw;
            }
            .modal h2 {
                font-size: 16px;
            }
            .modal input {
                font-size: 16px;
                padding: 10px;
            }
            .modal-actions {
                flex-wrap: wrap;
            }
            .modal-btn {
                font-size: 14px;
                padding: 8px 18px;
            }

            /* 设置面板：垂直堆叠 */
            .settings-panels {
                flex-direction: column;
                min-height: auto;
                max-height: 50vh;
            }
            .settings-route-tabs {
                width: 100%;
            }
            .settings-route-tab {
                flex: 1;
                padding: 8px 10px;
            }
            .settings-search-panel {
                min-height: auto;
                max-height: 50vh;
                padding: 12px;
            }
            .settings-appearance-panel {
                min-height: auto;
                max-height: 50vh;
                padding: 12px;
            }
            .settings-left {
                width: 100%;
                flex-shrink: 0;
                max-height: 140px;
                border-right: none;
                border-bottom: 1px solid var(--border-color);
            }
            .settings-right {
                padding: 12px;
                max-height: 200px;
            }
            .settings-right label {
                font-size: 12px;
            }
            .settings-right input:not(.model-input) {
                font-size: 14px;
                padding: 8px 10px;
            }

            /* 设置 - 模型标签 */
            .model-tag {
                font-size: 12px;
                padding: 4px 9px;
            }

            /* 设置导出导入按钮 */
            .export-import-btns {
                flex-wrap: wrap;
                gap: 6px;
            }
            .modal-header-row {
                flex-wrap: wrap;
                gap: 8px;
            }

            /* 模型下拉 */
            .model-dropdown {
                min-width: 0;
                max-width: calc(100vw - 24px);
            }

            /* Toast */
            .toast {
                top: 16px;
                padding: 8px 18px;
                font-size: 13px;
                max-width: 90vw;
                white-space: nowrap;
                overflow: hidden;
                text-overflow: ellipsis;
            }

            /* 消息操作按钮 */
            .message-actions svg {
                width: 16px;
                height: 16px;
            }
            .msg-model-tag, .msg-preset-tag {
                font-size: 10px;
                padding: 1px 6px;
            }

            /* Markdown 代码块 */
            .message-content pre, .thought-content pre {
                padding: 10px 12px;
                font-size: 12px;
            }
            .code-block-header, .mermaid-toolbar {
                padding: 6px 12px;
                flex-wrap: wrap;
            }
            .code-copy-btn, .code-run-btn, .mermaid-tool-btn, .mermaid-tool-copy {
                font-size: 11px;
            }

            /* 搜索弹窗 */
            #searchModal .modal {
                max-width: 94vw;
                margin-top: 20px;
            }
            #searchResults {
                max-height: 50vh;
            }

            /* 参数预设编辑 */
            .preset-edit-row {
                flex-wrap: wrap;
                gap: 6px;
            }
            .preset-edit-row label {
                min-width: 60px;
                font-size: 11px;
            }
            .preset-edit-row input,
            .preset-edit-row textarea,
            .preset-edit-row select {
                font-size: 14px;
            }
            .preset-slider-group .slider-label {
                font-size: 10px;
                min-width: 52px;
            }

            /* 折叠按钮 */
            .collapse-toggle {
                font-size: 11px;
                padding: 3px 10px;
            }

            /* 模式切换 */
            .mode-toggle-btn {
                padding: 4px 10px;
                font-size: 12px;
            }

            /* 生图控制面板 */
            .gen-controls-panel {
                padding: 0 10px 6px 10px;
            }
            .gen-controls-inner {
                padding: 10px 12px;
                gap: 8px;
            }
            .gen-row {
                gap: 6px;
            }
            .gen-row label {
                font-size: 11px;
                min-width: 36px;
            }
            .gen-row input[type="text"],
            .gen-row input[type="number"],
            .gen-row select {
                font-size: 12px;
                padding: 5px 8px;
            }
            .generated-images img {
                max-width: 150px;
                max-height: 150px;
            }
            .settings-modal {
                width: 94vw;
                max-width: 94vw;
                height: 82dvh;
                min-height: 0;
                padding: 0;
                gap: 0;
                grid-template-columns: 128px minmax(0, 1fr);
                margin: 0;
            }
            .settings-modal .settings-route-tabs {
                width: auto;
                padding: 46px 6px 10px;
            }
            .settings-modal .settings-route-tab {
                flex: none;
                padding: 8px 9px;
                font-size: 12px;
            }
            .settings-modal .modal-header-row {
                padding: 14px;
                min-height: 54px;
            }
            .settings-modal .settings-search-panel,
            .settings-modal .settings-webdav-panel,
            .settings-modal .settings-appearance-panel,
            .settings-modal .settings-right {
                padding: 12px;
                max-height: none;
            }
        }

        /* 平板中等屏幕 */
        @media (min-width: 769px) and (max-width: 1024px) {
            :root {
                --chat-max-width: 640px;
            }
            .sidebar {
                width: 220px;
                padding: 18px 12px;
            }
            .sidebar.hidden {
                width: 56px;
                padding: 14px 8px;
            }
            .welcome-screen h1 {
                font-size: 28px;
            }
        }