:root {
        --bg-color: #0d1117;
        --text-color: #c9d1d9;
        --accent-color: #58a6ff;
        --border-color: #30363d;
        --prompt-color: #3fb950;
        --error-color: #f85149;
        --warning-color: #d29922;
        --success-color: #238636;
        --font-family: 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
        --safe-top: env(safe-area-inset-top, 0px);
        --safe-right: env(safe-area-inset-right, 0px);
        --safe-bottom: env(safe-area-inset-bottom, 0px);
        --safe-left: env(safe-area-inset-left, 0px);
    }

        * {
            box-sizing: border-box;
            scrollbar-width: thin;
            scrollbar-color: var(--border-color) var(--bg-color);
            -webkit-tap-highlight-color: rgba(88, 166, 255, 0.14);
        }

        *::-webkit-scrollbar {
            width: 8px;
        }

        *::-webkit-scrollbar-track {
            background: var(--bg-color);
        }

        *::-webkit-scrollbar-thumb {
            background-color: var(--border-color);
            border-radius: 4px;
            border: 2px solid var(--bg-color);
        }

        html, body {
            height: 100%;
            margin: 0;
            padding: 0;
            font-family: var(--font-family);
            background-color: var(--bg-color);
            color: var(--text-color);
            color-scheme: dark;
            font-size: clamp(13px, 2.2vw, 14px);
            overflow: hidden;
            -webkit-text-size-adjust: 100%;
        }

        button, input, select, textarea {
            font: inherit;
            touch-action: manipulation;
        }

        #terminal {
            display: flex;
            flex-direction: column;
            height: 100vh;
            height: 100dvh;
            width: 100%;
            background:
                radial-gradient(circle at top left, rgba(88, 166, 255, 0.13), transparent 30%),
                radial-gradient(circle at bottom right, rgba(63, 185, 80, 0.08), transparent 25%),
                #0b0f14;
        }

        .storage-warning {
            background-color: var(--warning-color);
            color: #000;
            padding: 5px 10px;
            text-align: center;
            font-size: 0.9em;
            display: none;
            transition: background-color 0.3s ease, color 0.3s ease, opacity 0.3s ease;
        }

        .storage-warning.online {
            background-color: var(--success-color);
            color: #fff;
        }

        .storage-warning.offline {
            background-color: var(--error-color);
            color: #fff;
        }

        .app-shell {
            position: relative;
            display: flex;
            flex: 1;
            min-height: 0;
            overflow: hidden;
        }

        .sidebar {
            position: relative;
            z-index: 4;
            display: flex;
            flex-direction: column;
            gap: 16px;
            width: clamp(296px, 25vw, 360px);
            min-width: 280px;
            padding: calc(18px + var(--safe-top)) calc(16px + var(--safe-right)) calc(16px + var(--safe-bottom)) calc(16px + var(--safe-left));
            border-right: 1px solid rgba(48, 54, 61, 0.9);
            background:
                linear-gradient(180deg, rgba(13, 17, 23, 0.98), rgba(10, 14, 20, 0.96)),
                var(--bg-color);
            box-shadow: inset -1px 0 0 rgba(255, 255, 255, 0.02);
            overscroll-behavior: contain;
        }

        .sidebar-header {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .sidebar-brand-row {
            display: flex;
            align-items: flex-start;
            justify-content: space-between;
            gap: 12px;
        }

        .sidebar-kicker {
            color: var(--accent-color);
            font-size: 0.78em;
            font-weight: 700;
            letter-spacing: 0.12em;
            text-transform: uppercase;
        }

        .sidebar-brand {
            margin-top: 4px;
            font-size: 1.45em;
            font-weight: 700;
            letter-spacing: -0.03em;
        }

        .sidebar-caption {
            color: #8b949e;
            font-size: 0.9em;
            line-height: 1.5;
        }

        .sidebar-icon-button {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 38px;
            height: 38px;
            flex-shrink: 0;
            padding: 0;
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 12px;
            background: rgba(255, 255, 255, 0.03);
            color: var(--text-color);
            cursor: pointer;
            transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
        }

        #sidebar-close-button {
            display: none;
            font-size: 1.3rem;
            line-height: 1;
        }

        .primary-sidebar-button,
        .sidebar-actions button,
        #upload-button,
        #send-button {
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 14px;
            font-family: inherit;
            font-size: 0.95em;
            cursor: pointer;
            transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease, opacity 0.2s ease;
        }

        .primary-sidebar-button {
            width: 100%;
            padding: 12px 14px;
            background: linear-gradient(135deg, rgba(88, 166, 255, 0.22), rgba(88, 166, 255, 0.08));
            color: #f0f6fc;
            border-color: rgba(88, 166, 255, 0.38);
            font-weight: 600;
            text-align: left;
        }

        .primary-sidebar-button:disabled,
        .sidebar-actions button:disabled,
        .sidebar-icon-button:disabled,
        #upload-button:disabled,
        #send-button:disabled {
            opacity: 0.45;
            cursor: not-allowed;
            transform: none;
        }

        .session-item:focus-visible,
        .session-item-main:focus-visible,
        .primary-sidebar-button:focus-visible,
        .sidebar-actions button:focus-visible,
        .sidebar-icon-button:focus-visible,
        .session-item-delete:focus-visible,
        .message-action-button:focus-visible,
        .branch-switch-button:focus-visible,
        .branch-selector:focus-visible {
            outline: none;
            box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.16);
        }

        .sidebar-section-title,
        .sidebar-footer-title {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 8px;
            color: #8b949e;
            font-size: 0.84em;
            font-weight: 600;
            letter-spacing: 0.04em;
            text-transform: uppercase;
        }

        .session-count-badge {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            min-width: 28px;
            height: 28px;
            padding: 0 8px;
            border-radius: 999px;
            background: rgba(88, 166, 255, 0.14);
            color: var(--accent-color);
            font-size: 0.95em;
            font-weight: 700;
        }

        .session-list {
            flex: 1;
            min-height: 0;
            display: flex;
            flex-direction: column;
            gap: 10px;
            overflow-x: hidden;
            overflow-y: auto;
            padding: 6px 8px 12px 2px;
            scrollbar-gutter: stable;
            overscroll-behavior: contain;
        }

        .session-item {
            position: relative;
            z-index: 0;
            isolation: isolate;
            width: 100%;
        }

        .session-item-main {
            width: 100%;
            padding: 13px 14px;
            padding-right: 52px;
            border: 1px solid rgba(48, 54, 61, 0.9);
            border-radius: 16px;
            background: linear-gradient(180deg, rgba(255, 255, 255, 0.03), rgba(255, 255, 255, 0.015));
            color: var(--text-color);
            text-align: left;
            cursor: pointer;
            font-family: inherit;
            font-size: inherit;
            transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
        }

        .session-item-main.is-active {
            border-color: rgba(88, 166, 255, 0.5);
            background: linear-gradient(180deg, rgba(88, 166, 255, 0.16), rgba(255, 255, 255, 0.02));
            box-shadow: inset 0 0 0 1px rgba(88, 166, 255, 0.08);
        }

        .session-item-delete {
            position: absolute;
            top: 10px;
            right: 10px;
            z-index: 2;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 30px;
            height: 30px;
            padding: 0;
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 10px;
            background: rgba(11, 15, 20, 0.78);
            color: #8b949e;
            cursor: pointer;
            transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease, color 0.2s ease, opacity 0.2s ease;
        }

        .session-item-delete:disabled,
        .message-action-button:disabled,
        .branch-switch-button:disabled,
        .branch-selector:disabled {
            opacity: 0.45;
            cursor: not-allowed;
            transform: none;
        }

        .session-item-title {
            display: block;
            font-weight: 600;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .session-item-preview {
            display: -webkit-box;
            margin-top: 6px;
            color: #8b949e;
            font-size: 0.86em;
            line-height: 1.45;
            overflow: hidden;
            overflow-wrap: anywhere;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
        }

        .session-item-meta {
            display: block;
            margin-top: 8px;
            color: #6e7681;
            font-size: 0.8em;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .session-empty {
            padding: 24px 16px;
            border: 1px dashed rgba(88, 166, 255, 0.22);
            border-radius: 16px;
            background: rgba(255, 255, 255, 0.02);
            color: #8b949e;
            line-height: 1.6;
            text-align: center;
        }

        .sidebar-footer {
            display: flex;
            flex-direction: column;
            gap: 10px;
            padding-top: 12px;
            border-top: 1px solid rgba(48, 54, 61, 0.9);
        }

        .sidebar-footer select {
            width: 100%;
            padding: 10px 12px;
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 14px;
            background: rgba(1, 4, 9, 0.9);
            color: var(--text-color);
            font-family: inherit;
            font-size: 0.95em;
            outline: none;
        }

        .sidebar-footer select:focus {
            border-color: rgba(88, 166, 255, 0.48);
        }

        .loading-indicator {
            display: none;
            padding: 8px 12px;
            border-radius: 12px;
            background: rgba(88, 166, 255, 0.12);
            color: var(--accent-color);
            font-size: 0.88em;
        }

        .loading-indicator.show {
            display: inline-flex;
            align-items: center;
        }

        .sidebar-toggle-card {
            border-radius: 14px;
            background: rgba(255, 255, 255, 0.03);
        }

        .sidebar-actions {
            display: grid;
            grid-template-columns: repeat(2, minmax(0, 1fr));
            gap: 8px;
        }

        .sidebar-actions button {
            padding: 10px 12px;
            background: rgba(255, 255, 255, 0.03);
            color: var(--text-color);
        }

        .workspace {
            position: relative;
            display: flex;
            flex: 1;
            min-width: 0;
            min-height: 0;
            flex-direction: column;
            background: linear-gradient(180deg, rgba(9, 12, 17, 0.92), rgba(9, 12, 17, 0.98));
        }

        .toolbar {
            position: sticky;
            top: 0;
            z-index: 2;
            background: rgba(11, 15, 20, 0.78);
            border-bottom: 1px solid rgba(48, 54, 61, 0.75);
            backdrop-filter: blur(16px);
        }

        .workspace-topbar {
            display: flex;
            align-items: center;
            gap: 14px;
            padding: max(16px, var(--safe-top)) calc(clamp(16px, 2.6vw, 24px) + var(--safe-right)) 16px calc(clamp(16px, 2.6vw, 24px) + var(--safe-left));
        }

        .workspace-heading {
            min-width: 0;
            flex: 1;
        }

        .workspace-title {
            font-size: 1.18em;
            font-weight: 700;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .workspace-meta {
            margin-top: 4px;
            color: #8b949e;
            font-size: 0.9em;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .sidebar-overlay {
            position: fixed;
            inset: 0;
            z-index: 3;
            border: none;
            background: rgba(0, 0, 0, 0.45);
            opacity: 0;
            pointer-events: none;
            transition: opacity 0.25s ease;
        }

        .sidebar-overlay.show {
            opacity: 1;
            pointer-events: auto;
        }

        #sidebar-toggle-button {
            display: none;
        }

        .switch-container {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 10px 12px;
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 14px;
            background-color: rgba(255, 255, 255, 0.02);
            transition: border-color 0.2s;
        }

        .switch-container:hover {
            border-color: rgba(88, 166, 255, 0.42);
        }

        .switch-container label {
            cursor: pointer;
            user-select: none;
            font-size: 0.9em;
        }

        .switch {
            position: relative;
            display: inline-block;
            width: 40px;
            height: 20px;
        }

        .switch input {
            opacity: 0;
            width: 0;
            height: 0;
        }

        .slider {
            position: absolute;
            cursor: pointer;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background-color: var(--border-color);
            transition: 0.3s;
            border-radius: 20px;
        }

        .slider:before {
            position: absolute;
            content: "";
            height: 14px;
            width: 14px;
            left: 3px;
            bottom: 3px;
            background-color: white;
            transition: 0.3s;
            border-radius: 50%;
        }

        input:checked + .slider {
            background-color: var(--prompt-color);
        }

        input:checked + .slider:before {
            transform: translateX(20px);
        }

        #chat-log {
            flex-grow: 1;
            display: flex;
            flex-direction: column;
            padding: 24px clamp(16px, 3vw, 28px) 20px;
            overflow-y: auto;
            word-wrap: break-word;
            min-height: 0;
            scrollbar-gutter: stable;
        }

        .message {
            width: min(100%, 960px);
            margin: 0 auto 16px;
            padding: 16px 18px;
            border: 1px solid rgba(48, 54, 61, 0.75);
            border-radius: 18px;
            background: rgba(255, 255, 255, 0.025);
            box-shadow: 0 10px 24px rgba(0, 0, 0, 0.12);
        }

        .message:last-child {
            margin-bottom: 0;
        }

        .message-header {
            display: flex;
            align-items: center;
            flex-wrap: wrap;
            gap: 6px 10px;
            margin-bottom: 8px;
        }

        .message-header-actions {
            margin-left: auto;
            display: inline-flex;
            align-items: center;
            gap: 8px;
        }

        .message-header .role {
            font-weight: bold;
        }

        .search-badge {
            display: inline-block;
            margin-left: 6px;
            font-size: 0.85em;
            opacity: 0.8;
        }

        .user .message-header .role {
            color: var(--prompt-color);
        }

        .assistant .message-header .role {
            color: var(--accent-color);
        }

        .message-time {
            color: #6e7681;
            font-size: 0.85em;
        }

        .message-action-button,
        .branch-switch-button {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            min-height: 30px;
            padding: 5px 10px;
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 999px;
            background: rgba(255, 255, 255, 0.03);
            color: #8b949e;
            cursor: pointer;
            font-size: 0.82em;
            line-height: 1;
            transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease, color 0.2s ease, opacity 0.2s ease;
        }

        .message-delete-button {
            color: #f85149;
        }

        .branch-switcher {
            display: flex;
            align-items: center;
            gap: 8px;
            margin-top: 12px;
            padding-top: 10px;
            border-top: 1px solid rgba(48, 54, 61, 0.7);
        }

        .branch-selector {
            min-width: 0;
            max-width: min(340px, 62vw);
            height: 32px;
            padding: 5px 10px;
            border: 1px solid rgba(48, 54, 61, 0.95);
            border-radius: 999px;
            background: rgba(1, 4, 9, 0.82);
            color: var(--text-color);
            font-family: inherit;
            font-size: 0.82em;
            outline: none;
        }

        .branch-count {
            flex-shrink: 0;
            color: #6e7681;
            font-size: 0.82em;
            font-variant-numeric: tabular-nums;
        }

        .message-content {
            white-space: normal;
            overflow-wrap: anywhere;
            line-height: 1.5;
            max-width: 100%;
        }

        .message-content p {
            margin: 0 0 8px;
        }

        .message-content h1, .message-content h2, .message-content h3 {
            border-bottom: 1px solid var(--border-color);
            padding-bottom: 4px;
            margin-top: 12px;
        }

        .message-content code {
            background-color: #22272e;
            padding: .2em .4em;
            margin: 0;
            font-size: 85%;
            border-radius: 3px;
            font-family: 'SF Mono', 'Consolas', 'Courier New', monospace;
        }

        .message-content pre {
            background-color: #161b22;
            padding: 10px;
            border-radius: 5px;
            overflow-x: auto;
            position: relative;
            white-space: pre;
            max-width: 100%;
        }

        .message-content pre code {
            padding: 0;
            background: none;
            white-space: pre;
        }

        .message-content blockquote {
            border-left: 3px solid var(--border-color);
            padding-left: 10px;
            color: #8b949e;
            margin-left: 0;
        }

        .message-content ul, .message-content ol {
            padding-left: 20px;
        }

        .message-content img {
            max-width: 100%;
            height: auto;
            border-radius: 5px;
            margin-top: 8px;
            border: 1px solid var(--border-color);
        }

        .message-content table {
            display: block;
            width: max-content;
            max-width: 100%;
            overflow-x: auto;
            border-collapse: collapse;
            margin: 10px 0;
        }

        .message-content table th, .message-content table td {
            border: 1px solid var(--border-color);
            padding: 8px;
            text-align: left;
        }

        .message-content table th {
            background-color: #161b22;
        }

        .katex {
            font-size: 1.1em;
        }

        .katex-display {
            margin: 1em 0;
            overflow-x: auto;
            overflow-y: hidden;
        }

        .error-message {
            color: var(--error-color);
            background-color: rgba(248, 81, 73, 0.1);
            padding: 10px;
            border-radius: 5px;
            border-left: 3px solid var(--error-color);
        }

        .input-container {
            padding: 0 calc(clamp(12px, 2vw, 18px) + var(--safe-right)) calc(18px + var(--safe-bottom)) calc(clamp(12px, 2vw, 18px) + var(--safe-left));
            background: transparent;
        }

        #attachment-preview {
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 10px;
            width: min(100%, 1040px);
            margin: 0 auto 10px;
            padding: 9px 12px;
            background-color: rgba(34, 39, 46, 0.92);
            border: 1px solid rgba(48, 54, 61, 0.85);
            border-radius: 12px;
            font-size: 0.9em;
        }

        #attachment-preview span {
            flex: 1;
            min-width: 0;
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
        }

        #remove-attachment-button {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            min-width: 32px;
            min-height: 32px;
            background: none;
            border: none;
            color: var(--error-color);
            cursor: pointer;
            font-size: 1.2em;
            padding: 0 5px;
        }

        .input-area {
            display: flex;
            gap: 10px;
            align-items: flex-end;
            width: min(100%, 1040px);
            margin: 0 auto;
            padding: 14px;
            border: 1px solid rgba(48, 54, 61, 0.82);
            border-radius: 22px;
            background:
                linear-gradient(180deg, rgba(13, 17, 23, 0.92), rgba(10, 13, 18, 0.98)),
                var(--bg-color);
            box-shadow: 0 18px 42px rgba(0, 0, 0, 0.2);
        }

        #user-input {
            flex-grow: 1;
            min-height: 52px;
            background-color: rgba(1, 4, 9, 0.96);
            color: var(--text-color);
            border: 1px solid rgba(48, 54, 61, 0.9);
            border-radius: 16px;
            padding: 14px 15px;
            font-family: inherit;
            font-size: 16px;
            resize: none;
            overflow-y: auto;
            max-height: 33dvh;
            transition: border-color 0.2s, box-shadow 0.2s;
        }

        #user-input:focus {
            border-color: rgba(88, 166, 255, 0.56);
            box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.12);
            outline: none;
        }

        #send-button, #upload-button {
            padding: 13px 16px;
            background: rgba(255, 255, 255, 0.04);
            color: var(--text-color);
        }

        #search-button {
            padding: 13px 16px;
            background: rgba(255, 255, 255, 0.04);
            color: var(--text-color);
            font-size: 1.1em;
            transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease, opacity 0.2s ease;
        }

        #search-button.active {
            background: linear-gradient(135deg, rgba(63, 185, 80, 0.24), rgba(63, 185, 80, 0.12));
            border-color: rgba(63, 185, 80, 0.38);
            color: #f0f6fc;
        }

        #send-button {
            background: linear-gradient(135deg, rgba(88, 166, 255, 0.24), rgba(88, 166, 255, 0.12));
            color: #f0f6fc;
        }

        .modal {
            display: none;
            position: fixed;
            z-index: 1000;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            padding: max(16px, var(--safe-top)) max(16px, var(--safe-right)) max(16px, var(--safe-bottom)) max(16px, var(--safe-left));
            background-color: rgba(0,0,0,0.7);
            align-items: center;
            justify-content: center;
            overscroll-behavior: contain;
        }

        .modal.show {
            display: flex;
        }

        .modal-content {
            background:
                linear-gradient(180deg, rgba(13, 17, 23, 0.98), rgba(10, 13, 18, 0.98)),
                var(--bg-color);
            padding: 22px;
            border-radius: 20px;
            border: 1px solid var(--border-color);
            box-shadow: 0 28px 70px rgba(0, 0, 0, 0.35);
            max-width: 640px;
            width: min(100%, 640px);
            max-height: min(84dvh, 860px);
            overflow-y: auto;
            overscroll-behavior: contain;
        }

        .modal-header {
            font-weight: bold;
            margin-bottom: 15px;
            font-size: 1.2em;
            color: var(--accent-color);
        }

        .modal-body {
            margin-bottom: 15px;
        }

        .modal-body label {
            display: block;
            margin-bottom: 5px;
            color: var(--text-color);
        }

        .modal-body input, .modal-body textarea, .modal-body select {
            width: 100%;
            padding: 10px 12px;
            background-color: #010409;
            color: var(--text-color);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            font-family: inherit;
            font-size: 16px;
            margin-bottom: 10px;
        }

        .modal-body textarea {
            resize: vertical;
            min-height: 100px;
        }

        .modal-body input:focus, .modal-body textarea:focus, .modal-body select:focus {
            border-color: var(--accent-color);
            outline: none;
        }

        .modal-body .hint {
            font-size: 0.85em;
            color: #8b949e;
            margin-top: -8px;
            margin-bottom: 10px;
        }

        .modal-body .checkbox-row {
            display: flex;
            align-items: center;
            gap: 8px;
            cursor: pointer;
            margin-bottom: 6px;
        }

        .modal-body .checkbox-row input[type="checkbox"] {
            width: 16px;
            height: 16px;
            margin: 0;
            flex: none;
            accent-color: var(--accent-color);
        }

        .modal-body .checkbox-row span {
            font-size: 0.95em;
            color: var(--text-color);
        }

        .modal-body .readonly-url {
            width: 100%;
            margin-bottom: 10px;
            padding: 10px 12px;
            border: 1px solid rgba(48, 54, 61, 0.9);
            border-radius: 12px;
            background: rgba(1, 4, 9, 0.8);
            color: #8b949e;
            font-size: 0.9em;
            word-break: break-all;
        }

        .modal-footer {
            display: flex;
            gap: 10px;
            justify-content: flex-end;
        }

        .modal-footer button {
            min-height: 44px;
            padding: 10px 16px;
            background-color: var(--bg-color);
            color: var(--text-color);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            cursor: pointer;
            font-family: inherit;
            font-size: inherit;
        }

        .modal-footer button.primary {
            background-color: var(--accent-color);
            color: var(--bg-color);
            border-color: var(--accent-color);
        }

        .toggle-advanced-button {
            width: 100%;
            min-height: 44px;
            padding: 10px 16px;
            margin-bottom: 10px;
            background-color: rgba(255, 255, 255, 0.03);
            color: var(--text-color);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            cursor: pointer;
            font-family: inherit;
            font-size: inherit;
            text-align: left;
            transition: background-color 0.2s, border-color 0.2s;
        }

        .toggle-advanced-button:hover {
            background-color: rgba(255, 255, 255, 0.05);
            border-color: rgba(88, 166, 255, 0.45);
        }

        #toggle-advanced-icon {
            display: inline-block;
            transition: transform 0.2s;
            margin-right: 6px;
        }

        #toggle-advanced-icon.expanded {
            transform: rotate(90deg);
        }

        #advanced-settings {
            margin-top: 10px;
        }

        .copy-code-button {
            position: absolute;
            top: 8px;
            right: 8px;
            min-height: 32px;
            padding: 6px 10px;
            border: 1px solid rgba(72, 79, 88, 0.95);
            border-radius: 8px;
            background: rgba(22, 27, 34, 0.92);
            color: var(--text-color);
            font-size: 12px;
            cursor: pointer;
            opacity: 0.82;
            transition: opacity 0.2s ease, border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
        }

        .copy-code-button:focus-visible {
            outline: none;
            opacity: 1;
            border-color: rgba(88, 166, 255, 0.5);
            box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.16);
        }

@media (min-width: 1280px) {
            .sidebar {
                width: clamp(320px, 23vw, 380px);
            }

            .workspace-topbar {
                padding-left: clamp(24px, 3vw, 36px);
                padding-right: clamp(24px, 3vw, 36px);
            }

            #chat-log {
                padding-left: clamp(24px, 3vw, 36px);
                padding-right: clamp(24px, 3vw, 36px);
            }

            .message {
                width: min(100%, 1040px);
            }

            .input-area,
            #attachment-preview {
                width: min(100%, 1080px);
            }
        }

@media (max-width: 900px) {
            .sidebar {
                position: fixed;
                top: 0;
                left: 0;
                bottom: 0;
                width: min(88vw, 360px);
                min-width: 0;
                padding-top: calc(18px + var(--safe-top));
                padding-bottom: calc(16px + var(--safe-bottom));
                transform: translateX(-100%);
                transition: transform 0.25s ease;
                box-shadow: 24px 0 48px rgba(0, 0, 0, 0.28);
            }

            .sidebar.is-open {
                transform: translateX(0);
            }

            #sidebar-close-button,
            #sidebar-toggle-button {
                display: inline-flex;
            }

            .workspace-topbar {
                padding: max(14px, var(--safe-top)) calc(16px + var(--safe-right)) 14px calc(16px + var(--safe-left));
            }

            #chat-log {
                padding: 18px calc(14px + var(--safe-right)) 16px calc(14px + var(--safe-left));
            }

            .input-container {
                padding: 0 calc(12px + var(--safe-right)) calc(12px + var(--safe-bottom)) calc(12px + var(--safe-left));
            }

            /* 触摸目标放大（移动端，趋近 44px） */
            .sidebar-icon-button {
                width: 44px;
                height: 44px;
            }

            .session-item-delete {
                width: 40px;
                height: 40px;
            }

            .session-item-main {
                padding-right: 58px;
            }

            .message-action-button,
            .branch-switch-button {
                min-height: 40px;
                padding: 8px 16px;
            }

            .copy-code-button {
                min-height: 38px;
                padding: 8px 12px;
            }

            #remove-attachment-button {
                min-width: 44px;
                min-height: 44px;
            }
        }

@media (max-width: 600px) {
            .workspace-topbar {
                align-items: flex-start;
                gap: 12px;
            }

            .workspace-title,
            .workspace-meta {
                white-space: normal;
            }

            .sidebar {
                padding: calc(16px + var(--safe-top)) calc(14px + var(--safe-right)) calc(14px + var(--safe-bottom)) calc(14px + var(--safe-left));
            }

            .sidebar-actions {
                grid-template-columns: 1fr;
            }

            .message {
                padding: 14px 15px;
                border-radius: 16px;
            }

            .session-item-main {
                padding-right: 58px;
            }

            .session-item-delete {
                top: 9px;
                right: 9px;
            }

            .message-header-actions {
                margin-left: 0;
                width: 100%;
                flex-wrap: wrap;
                justify-content: flex-end;
            }

            .branch-switcher {
                flex-wrap: wrap;
            }

            .branch-selector {
                flex: 1;
                max-width: none;
            }

            .message-content pre {
                padding-top: 46px;
            }

            #attachment-preview {
                flex-wrap: wrap;
                gap: 8px;
                padding: 10px 12px;
            }

            .input-area {
                flex-wrap: wrap;
                gap: 8px;
                padding: 12px;
                border-radius: 18px;
            }

            #user-input {
                width: 100%;
                min-height: 92px;
                max-height: 34dvh;
            }

            #upload-button,
            #send-button {
                flex: 1;
                min-height: 48px;
            }

            .modal-content {
                width: 100%;
                max-height: calc(100dvh - 16px);
                padding: 18px;
                border-radius: 18px;
            }

            .modal-footer {
                flex-direction: column-reverse;
            }

            .modal-footer button {
                width: 100%;
            }
        }

@media (max-width: 420px) {
            .sidebar {
                width: 100vw;
                border-right: none;
            }

            .workspace-topbar {
                padding-left: calc(12px + var(--safe-left));
                padding-right: calc(12px + var(--safe-right));
            }

            #chat-log {
                padding-left: calc(12px + var(--safe-left));
                padding-right: calc(12px + var(--safe-right));
            }

            .input-container {
                padding-left: calc(10px + var(--safe-left));
                padding-right: calc(10px + var(--safe-right));
            }
        }

        .thinking-indicator {
            display: inline-block;
            animation: blink 1.5s infinite;
        }

@keyframes blink {
            0%, 100% {
                opacity: 1;
            }
            50% {
                opacity: 0.3;
            }
        }

        /* 思维链（reasoning）折叠区 */
        .reasoning-block {
            margin: 0 0 12px;
            border: 1px solid var(--border-color);
            border-left: 3px solid var(--accent-color);
            border-radius: 8px;
            background-color: rgba(110, 118, 129, 0.08);
            overflow: hidden;
        }

        .reasoning-summary {
            cursor: pointer;
            list-style: none;
            padding: 7px 12px;
            font-size: 0.86em;
            color: #8b949e;
            user-select: none;
            display: flex;
            align-items: center;
            gap: 6px;
            transition: color 0.15s;
        }

        .reasoning-summary::-webkit-details-marker {
            display: none;
        }

        .reasoning-summary::after {
            content: '▸';
            margin-left: auto;
            transition: transform 0.15s;
        }

        .reasoning-block[open] > .reasoning-summary::after {
            transform: rotate(90deg);
        }

        .reasoning-summary:hover {
            color: var(--text-color);
        }

        .reasoning-block[open] > .reasoning-summary {
            border-bottom: 1px solid var(--border-color);
        }

        .reasoning-body {
            padding: 4px 14px;
            font-size: 0.88em;
            line-height: 1.65;
            color: #8b949e;
        }

        .reasoning-body p:first-child {
            margin-top: 6px;
        }

        .reasoning-body p:last-child {
            margin-bottom: 8px;
        }

        .reasoning-body pre {
            background-color: rgba(1, 4, 9, 0.5);
        }

        .shortcuts-hint {
            position: fixed;
            bottom: calc(16px + var(--safe-bottom));
            right: calc(20px + var(--safe-right));
            background-color: #161b22;
            border: 1px solid var(--border-color);
            border-radius: 14px;
            padding: 10px 15px;
            font-size: 0.85em;
            opacity: 0;
            pointer-events: none;
            transition: opacity 0.3s;
            z-index: 999;
            max-width: 250px;
            box-shadow: 0 18px 40px rgba(0, 0, 0, 0.26);
        }

        .shortcuts-hint.show {
            opacity: 0.9;
        }

        .shortcuts-hint h4 {
            margin: 0 0 8px 0;
            color: var(--accent-color);
        }

        .shortcuts-hint ul {
            margin: 0;
            padding-left: 20px;
            list-style: none;
        }

        .shortcuts-hint li {
            margin: 4px 0;
        }

        .shortcuts-hint kbd {
            background-color: var(--bg-color);
            border: 1px solid var(--border-color);
            border-radius: 3px;
            padding: 2px 5px;
            font-size: 0.9em;
        }

@media (max-width: 600px) {
            .shortcuts-hint {
                left: calc(12px + var(--safe-left));
                right: calc(12px + var(--safe-right));
                bottom: calc(12px + var(--safe-bottom));
                max-width: none;
            }
        }

@media (hover: hover) and (pointer: fine) {
            .sidebar-icon-button:hover {
                transform: translateY(-1px);
                border-color: rgba(88, 166, 255, 0.45);
                background: rgba(88, 166, 255, 0.08);
            }

            .primary-sidebar-button:hover,
            .sidebar-actions button:hover,
            #upload-button:hover,
            #send-button:hover,
            .modal-footer button:hover,
            .copy-code-button:hover,
            .message-action-button:hover,
            .branch-switch-button:hover,
            .session-item-delete:hover {
                transform: translateY(-1px);
                border-color: rgba(88, 166, 255, 0.45);
            }

            .session-item:hover {
                z-index: 1;
            }

            .session-item:hover .session-item-main {
                transform: translateY(-1px);
                border-color: rgba(88, 166, 255, 0.34);
                box-shadow: 0 12px 24px rgba(0, 0, 0, 0.18);
            }

            .copy-code-button:hover {
                opacity: 1;
                background: rgba(30, 37, 47, 0.98);
            }

            .message-action-button:hover,
            .branch-switch-button:hover {
                color: var(--accent-color);
                background: rgba(88, 166, 255, 0.08);
            }

            .message-delete-button:hover {
                color: #ff7b72;
                background: rgba(248, 81, 73, 0.1);
                border-color: rgba(248, 81, 73, 0.34);
            }

            .session-item-delete:hover {
                color: #f0f6fc;
                background: rgba(248, 81, 73, 0.16);
                border-color: rgba(248, 81, 73, 0.38);
            }
        }

        .session-item:active,
        .session-item-main:active,
        .primary-sidebar-button:active,
        .sidebar-actions button:active,
        .sidebar-icon-button:active,
        #upload-button:active,
        #send-button:active,
        .modal-footer button:active,
        .copy-code-button:active,
        .message-action-button:active,
        .branch-switch-button:active,
        .session-item-delete:active {
            transform: translateY(0);
            filter: brightness(1.04);
        }

@media (prefers-reduced-motion: reduce) {
            .sidebar-icon-button,
            .primary-sidebar-button,
            .sidebar-actions button,
            .session-item,
            .session-item-main,
            #upload-button,
            #send-button,
            .modal-footer button,
            .copy-code-button,
            .message-action-button,
            .branch-switch-button,
            .branch-selector,
            .session-item-delete,
            .shortcuts-hint,
            .thinking-indicator {
                animation: none !important;
                transition-duration: 0.01ms !important;
            }
        }