/* ===== 消息气泡 ===== */
        .message {
            display: flex;
            gap: 14px;
            flex-wrap: wrap;
            align-items: flex-start;
            animation: fadeUp 0.3s ease;
            padding: 0;
        }
        .message .msg-actions {
            flex: 0 0 100%;
            width: 100%;
            display: flex;
            align-items: center;
            gap: 2px;
            padding-left: 50px;
            opacity: 0;
            transition: opacity 0.2s ease;
        }
        .message:hover .msg-actions {
            opacity: 1;
        }
        .message.latest .msg-actions {
            opacity: 1;
        }
        .message.user .msg-actions {
            padding-left: 0;
            padding-right: 50px;
            justify-content: flex-end;
        }
        @media (hover: none), (pointer: coarse) {
            .message .bubble .content,
            .message .bubble .thinking-inner {
                user-select: none;
                -webkit-user-select: none;
                -webkit-touch-callout: none;
            }
            .chat-inner.selecting .message .bubble .content,
            .chat-inner.selecting .message .bubble .thinking-inner {
                user-select: text;
                -webkit-user-select: text;
                -webkit-touch-callout: default;
            }
            .message:not(.latest) .msg-actions {
                display: none;
            }
            .message .msg-actions {
                opacity: 1;
                padding-left: 12px;
            }
            .message.user .msg-actions {
                padding-left: 0;
                padding-right: 12px;
            }
        }
        .msg-actions .action-btn,
        .msg-actions .nav-btn {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 28px;
            height: 28px;
            border: none;
            background: transparent;
            color: var(--text-muted);
            border-radius: 8px;
            cursor: pointer;
            transition: background 0.15s, color 0.15s;
        }
        .msg-actions .action-btn:hover,
        .msg-actions .nav-btn:hover {
            background: var(--bg-hover);
            color: var(--text-primary);
        }
        .msg-actions .version-nav {
            display: flex;
            align-items: center;
            gap: 2px;
            margin-right: 6px;
        }
        .msg-actions .version-count {
            font-size: 14px;
            color: var(--text-muted);
            min-width: 30px;
            text-align: center;
            font-variant-numeric: tabular-nums;
        }
        .message.user {
            align-self: flex-end;
            flex-direction: row-reverse;
        }
        .message.ai {
            align-self: flex-start;
        }
        .message .avatar {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            flex-shrink: 0;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 16px;
            font-weight: 600;
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            color: var(--text-secondary);
            box-shadow: var(--shadow-sm);
        }
        .message.user .avatar {
            background: var(--accent-gradient);
            color: #fff;
            border: none;
            box-shadow: 0 2px 8px var(--accent-glow);
        }
        .message.ai .avatar {
            background: linear-gradient(135deg, var(--bg-card), var(--bg-hover));
            border: 1px solid var(--border-color);
            color: var(--accent);
            box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--accent) 20%, transparent);
        }

        .message .bubble {
            background: var(--bg-card);
            padding: 18px 24px;
            border-radius: var(--radius);
            border: 1px solid var(--border-color);
            line-height: 1.7;
            font-size: 16px;
            word-break: break-word;
            position: relative;
            box-shadow: var(--shadow-sm);
            flex: 0 1 auto;
            max-width: 85%;
            min-width: 0;
        }
        .message.user .bubble {
            background: linear-gradient(135deg, var(--accent), var(--accent-2));
            border-color: transparent;
            color: #fff;
            border-top-right-radius: 4px;
            box-shadow: 0 4px 16px var(--accent-glow);
        }
        .message.ai .bubble {
            background:
                linear-gradient(180deg, color-mix(in srgb, var(--bg-card) 98%, var(--accent) 4%), var(--bg-card) 55%);
            border-color: var(--border-color);
            border-top-left-radius: 4px;
        }

        .message .bubble .model-tag {
            font-size: 12px;
            color: var(--text-muted);
            margin-bottom: 6px;
            display: flex;
            align-items: center;
            gap: 6px;
            font-weight: 500;
        }
        .message.ai .bubble .model-tag {
            color: var(--accent);
        }
        .message.user .bubble .model-tag {
            color: rgba(255, 255, 255, 0.7);
        }

        /* ===== Markdown 内容样式 ===== */
        .message .bubble .content {
            white-space: normal;
            line-height: 1.75;
        }

        .message .bubble .content h1,
        .message .bubble .content h2,
        .message .bubble .content h3 {
            font-weight: 700;
            margin: 1.2em 0 0.6em 0;
        }
        .message .bubble .content h1 {
            font-size: 2.0em;
        }
        .message .bubble .content h2 {
            font-size: 1.7em;
        }
        .message .bubble .content h3 {
            font-size: 1.4em;
        }

        .message .bubble .content p {
            margin: 0.6em 0;
        }

        .message .bubble .content ul,
        .message .bubble .content ol {
            padding-left: 2.4em;
            margin: 0.6em 0;
            list-style-position: outside;
        }
        .message .bubble .content li {
            margin-bottom: 0.3em;
        }

        .message .bubble .content blockquote {
            border-left: 6px solid var(--accent);
            padding: 0.4em 1.2em;
            margin: 0.8em 0;
            color: var(--text-secondary);
        }

        .message .bubble .content pre {
            position: relative;
            background: var(--code-bg);
            padding: 16px 20px;
            border-radius: 10px;
            overflow-x: auto;
            margin: 0.8em 0;
            border: 1px solid var(--border-color);
        }
        .message .bubble .content pre code {
            font-family: var(--code-font);
            font-size: 15px;
            background: transparent;
            padding: 0;
            display: block;
            white-space: pre;
        }
        .message .bubble .content .copy-btn,
        .message .bubble .thinking-inner .copy-btn {
            position: absolute;
            top: 8px;
            right: 8px;
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            color: var(--text-secondary);
            font-size: 12px;
            padding: 2px 10px;
            border-radius: 6px;
            cursor: pointer;
            opacity: 0;
            transition: opacity 0.2s;
            font-family: var(--font);
            font-weight: 500;
            backdrop-filter: blur(2px);
        }
        .message .bubble .content pre:hover .copy-btn,
        .message .bubble .thinking-inner pre:hover .copy-btn {
            opacity: 1;
        }
        .message .bubble .content .copy-btn:hover,
        .message .bubble .thinking-inner .copy-btn:hover {
            background: var(--accent);
            color: #fff;
            border-color: var(--accent);
        }
        .message.user .bubble .content pre {
            background: rgba(255, 255, 255, 0.1);
            border-color: rgba(255, 255, 255, 0.15);
        }
        .message.user .bubble .content .copy-btn {
            background: rgba(255, 255, 255, 0.15);
            border-color: rgba(255, 255, 255, 0.25);
            color: rgba(255, 255, 255, 0.8);
        }
        .message.user .bubble .content .copy-btn:hover {
            background: #fff;
            color: #000;
            border-color: #fff;
        }

        /* 思维链 */
        .thinking-area {
            margin-bottom: 8px;
            border-bottom: 1px solid var(--border-color);
            padding-bottom: 6px;
        }
        .thinking-area:empty {
            display: none;
        }
        .thinking-header {
            cursor: pointer;
            color: var(--text-muted);
            font-size: 14px;
            user-select: none;
            display: flex;
            align-items: center;
            gap: 4px;
            padding: 2px 0;
        }
        .thinking-header:hover {
            color: var(--text-secondary);
        }
        .thinking-header .arrow {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            transform: rotate(-90deg);
            transition: transform 0.3s ease;
        }
        .thinking-header .arrow.expanded {
            transform: rotate(0deg);
        }

        .thinking-body {
            display: grid;
            grid-template-rows: 0fr;
            transition: grid-template-rows 0.35s cubic-bezier(0.4, 0, 0.2, 1),
                        opacity 0.15s ease,
                        padding 0.2s ease,
                        margin 0.2s ease;
            overflow: hidden;
            font-size: 15px;
            color: var(--text-secondary);
            white-space: normal;
            line-height: 1.6;
            padding: 0 0 0 0;
            margin-top: 0;
        }
        .thinking-body.expanded {
            grid-template-rows: 1fr;
            padding: 8px 0 4px 0;
            margin-top: 4px;
            opacity: 1;
        }
        .thinking-body .thinking-inner {
            overflow: hidden;
        }
        .message .bubble .thinking-inner p { margin: 0.6em 0; }
        .message .bubble .thinking-inner ul,
        .message .bubble .thinking-inner ol { padding-left: 2.4em; margin: 0.6em 0; list-style-position: outside; }
        .message .bubble .thinking-inner li { margin-bottom: 0.3em; }
        .message .bubble .thinking-inner blockquote { border-left: 6px solid var(--accent); padding: 0.4em 1.2em; margin: 0.8em 0; color: var(--text-secondary); }
        .message .bubble .thinking-inner h1,
        .message .bubble .thinking-inner h2,
        .message .bubble .thinking-inner h3 { font-weight: 700; margin: 1.2em 0 0.6em 0; }
        .message .bubble .thinking-inner h1 { font-size: 1.4em; }
        .message .bubble .thinking-inner h2 { font-size: 1.3em; }
        .message .bubble .thinking-inner h3 { font-size: 1.2em; }
        .message .bubble .thinking-inner pre { position: relative; background: var(--code-bg); padding: 12px 16px; border-radius: 8px; overflow-x: auto; margin: 0.8em 0; border: 1px solid var(--border-color); }
        .message .bubble .thinking-inner pre code { font-family: var(--code-font); font-size: 14px; background: transparent; padding: 0; display: block; white-space: pre; }
        .message .bubble .thinking-inner a { color: var(--accent); }
        .message .bubble .thinking-inner strong { font-weight: 700; }

        /* 打字指示器 */
        .typing-indicator {
            display: none;
            align-self: flex-start;
            gap: 14px;
            max-width: 100%;
            animation: fadeUp 0.3s ease;
            padding: 0 6px;
        }
        .typing-indicator.show {
            display: flex;
        }
        .typing-indicator .avatar {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            flex-shrink: 0;
            background: linear-gradient(135deg, var(--bg-card), var(--bg-hover));
            border: 1px solid var(--border-color);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--accent);
            font-size: 16px;
            box-shadow: var(--shadow-sm);
        }
        .typing-indicator .dots {
            background:
                linear-gradient(180deg, color-mix(in srgb, var(--bg-card) 97%, var(--accent) 5%), var(--bg-card));
            padding: 14px 24px;
            border-radius: var(--radius);
            border: 1px solid var(--border-color);
            border-top-left-radius: 4px;
            display: flex;
            gap: 5px;
            box-shadow: var(--shadow-sm);
        }
        .typing-indicator .dots span {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--accent);
            opacity: 0.5;
            animation: typingBounce 1.4s infinite both;
        }
        .typing-indicator .dots span:nth-child(2) { animation-delay: 0.2s; }
        .typing-indicator .dots span:nth-child(3) { animation-delay: 0.4s; }
        @keyframes typingBounce {
            0%,60%,100% { transform: translateY(0); opacity: 0.4; }
            30% { transform: translateY(-8px); opacity: 1; }
        }
        @keyframes fadeUp {
            from { opacity: 0; transform: translateY(12px); }
            to { opacity: 1; transform: translateY(0); }
        }

        /* ===== Toast 专用动画 ===== */
        @keyframes toastFadeUp {
            from { opacity: 0; transform: translateX(-50%) translateY(12px); }
            to   { opacity: 1; transform: translateX(-50%) translateY(0); }
        }
        .toast-anim {
            animation: toastFadeUp 0.3s ease;
        }

        /* ===== 输入区域 ===== */
        .input-area {
            padding: 8px 20px 12px;
            flex-shrink: 0;
            background: var(--bg-primary);
            width: 100%;
            max-width: 768px;
            margin: 0 auto;
            position: relative;
        }
        .input-area .input-wrapper {
            position: relative;
            display: flex;
            gap: 12px;
            align-items: flex-end;
            background: color-mix(in srgb, var(--bg-secondary) 92%, var(--accent) 3%);
            border: 1px solid var(--border-color);
            border-radius: calc(var(--radius) + 2px);
            padding: 6px 6px 6px 18px;
            min-height: 58px;
            box-shadow: var(--shadow-sm);
        }
        .input-area .input-wrapper:focus-within {
            border-color: var(--accent);
            box-shadow: 0 0 0 3px var(--accent-glow), var(--shadow);
        }

        .input-area textarea {
            flex: 1;
            background: transparent;
            border: none;
            outline: none;
            color: var(--text-primary);
            font-size: 16px;
            font-family: var(--font);
            resize: none;
            padding: 10px 0 72px 0;
            max-height: 140px;
            line-height: 1.5;
            min-height: 120px;
        }
        .input-area textarea::placeholder {
            color: var(--text-muted);
        }

        .input-area .thinking-toggle {
            position: absolute;
            bottom: 14px;
            left: 14px;
            display: flex;
            align-items: center;
            gap: 6px;
            font-size: 15px;
            color: var(--text-muted);
            cursor: pointer;
            user-select: none;
            padding: 5px 16px;
            border-radius: 16px;
            background: color-mix(in srgb, var(--bg-card) 88%, transparent);
            border: 1px solid var(--border-color);
            transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
            z-index: 5;
            height: 30px;
            line-height: 1;
            box-shadow: var(--shadow-sm);
            backdrop-filter: blur(8px);
            -webkit-backdrop-filter: blur(8px);
        }
        .input-area .thinking-toggle:hover {
            background: var(--bg-hover);
        }
        .input-area .thinking-toggle.active {
            border-color: var(--accent);
            background: color-mix(in srgb, var(--accent) 18%, var(--bg-card));
            color: var(--accent);
            box-shadow: 0 0 0 2px var(--accent-glow);
        }
        .input-area .thinking-toggle .status-label {
            display: none;
        }

        .input-area .send-btn {
            background: var(--accent-gradient);
            border: none;
            color: #fff;
            width: 44px;
            height: 44px;
            border-radius: var(--radius-sm);
            cursor: pointer;
            font-size: 18px;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            margin-bottom: 2px;
            transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
            box-shadow: 0 2px 10px var(--accent-glow);
        }
        .input-area .send-btn:hover {
            transform: scale(1.05);
            box-shadow: 0 4px 16px var(--accent-glow);
            filter: brightness(1.05);
        }
        .input-area .send-btn:active {
            transform: scale(0.97);
        }
        .input-area .send-btn:disabled {
            opacity: 0.4;
            cursor: not-allowed;
            transform: none;
        }
        .input-area .send-btn svg {
            width: 22px;
            height: 22px;
        }
        .input-area .send-btn.is-stopping {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            color: var(--text-secondary);
        }
        .input-area .send-btn.is-stopping:hover {
            background: var(--bg-hover);
            transform: scale(1.03);
        }

        /* ===== 滚动到底部按钮 ===== */
        .scroll-bottom-btn {
            position: absolute;
            bottom: calc(100% + 12px);
            right: -6px;
            z-index: 30;
            width: 44px;
            height: 44px;
            border-radius: 50%;
            background: color-mix(in srgb, var(--bg-card) 90%, transparent);
            border: 1px solid var(--border-color);
            color: var(--text-secondary);
            font-size: 20px;
            cursor: pointer;
            box-shadow: var(--shadow-sm);
            display: none;
            align-items: center;
            justify-content: center;
            transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
            opacity: 0.9;
            backdrop-filter: blur(8px);
            -webkit-backdrop-filter: blur(8px);
        }
        .scroll-bottom-btn:hover {
            background: var(--bg-hover);
            transform: scale(1.08);
            box-shadow: var(--shadow);
            opacity: 1;
        }
        .scroll-bottom-btn.show {
            display: flex;
        }
        @media (max-width: 768px) {
            .scroll-bottom-btn {
                width: 38px;
                height: 38px;
                font-size: 18px;
                bottom: calc(100% + 8px);
                right: -6px;
            }
        }