:root {
    color-scheme: light;
    --font-sans: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-mono: "Fira Code", "SFMono-Regular", Consolas, monospace;
    --surface-0: #ffffff;
    --surface-1: #f5f7fb;
    --surface-2: #e6ebf5;
    --surface-3: #d5dfee;
    --border-color: rgba(27, 43, 65, 0.12);
    --border-strong: rgba(27, 43, 65, 0.24);
    --text-primary: #1b2b41;
    --text-secondary: rgba(27, 43, 65, 0.64);
    --text-tertiary: rgba(27, 43, 65, 0.45);
    --accent: #2563eb;
    --accent-soft: rgba(37, 99, 235, 0.12);
    --accent-strong: #1d4ed8;
    --danger: #e11d48;
    --danger-soft: rgba(225, 29, 72, 0.12);
    --shadow-sm: 0 4px 16px rgba(20, 37, 63, 0.08);
    --shadow-lg: 0 24px 48px rgba(15, 23, 42, 0.16);
    --radius-sm: 10px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --sidebar-width: clamp(280px, 22vw + 120px, 360px);
    --transition-base: 180ms ease;
}

body.dark-mode {
    color-scheme: dark;
    --surface-0: #0f172a;
    --surface-1: #111c31;
    --surface-2: #1b2943;
    --surface-3: #223256;
    --border-color: rgba(148, 163, 184, 0.18);
    --border-strong: rgba(148, 163, 184, 0.32);
    --text-primary: #e2e8f0;
    --text-secondary: rgba(226, 232, 240, 0.72);
    --text-tertiary: rgba(226, 232, 240, 0.45);
    --accent: #60a5fa;
    --accent-soft: rgba(96, 165, 250, 0.16);
    --accent-strong: #3b82f6;
    --danger: #f87171;
    --danger-soft: rgba(248, 113, 113, 0.16);
    --shadow-sm: 0 4px 20px rgba(2, 6, 23, 0.4);
    --shadow-lg: 0 30px 60px rgba(2, 6, 23, 0.55);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: var(--font-sans);
    background: var(--surface-1);
    color: var(--text-primary);
    overflow: hidden;
}

body, button, input, textarea, select {
    font-size: 16px;
    line-height: 1.5;
}

img, svg {
    display: block;
}

button {
    cursor: pointer;
    border: none;
    background: none;
    font: inherit;
    color: inherit;
}

button:disabled {
    cursor: not-allowed;
    opacity: 0.55;
}

ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

h1, h2, h3, h4, h5, h6 {
    margin: 0;
    font-weight: 600;
}

p {
    margin: 0;
}

kbd {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 26px;
    padding: 4px 6px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    background: var(--surface-1);
    box-shadow: inset 0 -1px 0 rgba(15, 23, 42, 0.06);
}

.app-shell {
    display: flex;
    min-height: 100vh;
    position: relative;
    background: var(--surface-1);
}

.sidebar {
    width: var(--sidebar-width);
    flex: 0 0 var(--sidebar-width);
    background: var(--surface-0);
    border-right: 1px solid var(--border-color);
    padding: 24px 20px 20px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    position: relative;
    z-index: 20;
    height: 100vh;
    overflow-y: auto;
    transition:
        transform var(--transition-base),
        box-shadow var(--transition-base),
        opacity var(--transition-base),
        width var(--transition-base),
        padding var(--transition-base),
        border-color var(--transition-base);
}

.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand i {
    width: 26px;
    height: 26px;
    color: var(--accent);
}

.brand-name {
    font-weight: 700;
    font-size: 1.1rem;
}

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

.section-heading {
    display: flex;
    align-items: center;
    justify-content: space-between;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.75rem;
}

.sidebar-search {
    position: relative;
}

.sidebar-search i {
    position: absolute;
    left: 12px;
    top: 50%;
    width: 18px;
    height: 18px;
    color: var(--text-tertiary);
    transform: translateY(-50%);
    pointer-events: none;
}

.sidebar-search input {
    width: 100%;
    background: var(--surface-1);
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    padding: 10px 14px 10px 40px;
    color: var(--text-primary);
    transition: border var(--transition-base), box-shadow var(--transition-base);
}

.sidebar-search input:focus {
    border-color: var(--accent);
    outline: none;
    box-shadow: 0 0 0 3px var(--accent-soft);
}

.folder-list, .chat-history-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
    max-height: min(38vh, 420px);
    overflow-y: auto;
    padding-right: 6px;
}

.folder-list::-webkit-scrollbar,
.chat-history-list::-webkit-scrollbar,
.chat-box::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

.folder-list::-webkit-scrollbar-thumb,
.chat-history-list::-webkit-scrollbar-thumb,
.chat-box::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.folder-list::-webkit-scrollbar-thumb:hover,
.chat-history-list::-webkit-scrollbar-thumb:hover,
.chat-box::-webkit-scrollbar-thumb:hover {
    background: var(--border-strong);
}

.chat-history-list li,
.folder-list li {
    padding: 10px 12px;
    border-radius: var(--radius-md);
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    transition: background var(--transition-base), border var(--transition-base), color var(--transition-base);
}

.chat-history-list li:hover,
.folder-list li:hover {
    background: var(--surface-1);
    border-color: var(--border-color);
    color: var(--text-primary);
}

.chat-history-list li.active,
.folder-list li.active {
    background: var(--accent-soft);
    border-color: var(--accent);
    color: var(--accent-strong);
}

.chat-history-list li .chat-title,
.folder-list li .folder-title {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}

.sidebar-footer {
    margin-top: auto;
    display: grid;
    gap: 10px;
}

.main-area {
    flex: 1 1 auto;
    min-width: 0;
    min-height: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
    background: var(--surface-1);
    position: relative;
    overflow: hidden;
}

.top-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 20px 28px 16px;
}

.top-bar-title {
    display: flex;
    align-items: center;
    gap: 12px;
}

.app-name {
    font-weight: 600;
    font-size: 1.1rem;
}

.status-pill {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 4px 10px;
    border-radius: 999px;
    background: var(--surface-2);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.status-pill.status-idle {
    background: var(--surface-2);
    border-color: var(--border-color);
    color: var(--text-secondary);
}

.status-pill.status-ready {
    background: var(--accent-soft);
    border-color: rgba(37, 99, 235, 0.35);
    color: var(--accent-strong);
}

.status-pill.status-busy {
    background: var(--danger-soft);
    border-color: rgba(225, 29, 72, 0.32);
    color: var(--danger);
}

.status-pill.status-error {
    background: var(--danger-soft);
    border-color: rgba(225, 29, 72, 0.45);
    color: var(--danger);
}


.model-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 12px 20px;
    background: var(--surface-0);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.model-details {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.model-details .button.secondary {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: var(--surface-1);
    border-radius: var(--radius-lg);
    padding: 10px 16px;
    font-weight: 500;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.chat-stats, .total-usage {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.model-controls {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.loading-indicator {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--accent-strong);
}

.spin {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.quick-prompts {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 28px;
    margin: 0;
    flex: 0 0 auto;
    background: var(--surface-0);
    border-bottom: 1px solid var(--border-color);
    overflow-x: auto;
    scrollbar-width: thin;
}

.chip {
    border-radius: 999px;
    padding: 8px 14px;
    background: var(--surface-2);
    border: 1px solid transparent;
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: background var(--transition-base), color var(--transition-base), border var(--transition-base);
}

.chip:hover {
    background: var(--accent-soft);
    border-color: rgba(37, 99, 235, 0.35);
    color: var(--accent-strong);
}

.chat-container {
    position: relative;
    flex: 1 1 auto;
    min-height: 0;
    overflow-y: auto;
    padding: 18px 24px 24px;
}

.chat-box {
    max-width: min(820px, 100%);
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.message {
    position: relative;
    border-radius: var(--radius-lg);
    padding: 18px 20px;
    background: var(--surface-0);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.message.user-message {
    margin-left: auto;
    background: var(--accent);
    border-color: transparent;
    color: #ffffff;
    box-shadow: none;
}

body.dark-mode .message.user-message {
    color: #0b1120;
}

.message.user-message .message-role,
.message.user-message .message-content,
.message.user-message .message-content p,
.message.user-message .message-content span {
    color: inherit;
}

.message-role {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-tertiary);
}

.message.user-message .message-role {
    color: rgba(255, 255, 255, 0.7);
}

.message-actions {
    position: absolute;
    top: 12px;
    right: 12px;
    display: inline-flex;
    gap: 6px;
}

.message-action-button {
    border-radius: 999px;
    background: transparent;
    border: 1px solid transparent;
    width: 28px;
    height: 28px;
    display: grid;
    place-items: center;
    color: var(--text-tertiary);
    transition: background var(--transition-base), border var(--transition-base), color var(--transition-base);
}

.message-action-button:hover {
    background: var(--surface-2);
    border-color: var(--border-color);
    color: var(--text-secondary);
}

.message-content {
    font-size: 1rem;
    line-height: 1.65;
    color: var(--text-primary);
}

.message-attachments {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.attachment-card {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--surface-0);
    overflow: hidden;
    transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.message.user-message .attachment-card {
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.35);
}

body.dark-mode .message.user-message .attachment-card {
    background: rgba(15, 23, 42, 0.45);
    border-color: rgba(148, 163, 184, 0.45);
}

.attachment-summary {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    padding: 12px 14px;
    font-weight: 500;
    color: var(--text-primary);
    list-style: none;
}

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

.message.user-message .attachment-summary {
    color: inherit;
}

.attachment-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    border-radius: var(--radius-sm);
    background: var(--surface-2);
    color: var(--text-secondary);
}

.message.user-message .attachment-icon {
    background: rgba(255, 255, 255, 0.18);
    color: inherit;
}

.attachment-name {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.attachment-meta {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

.message.user-message .attachment-meta {
    color: rgba(255, 255, 255, 0.7);
}

.attachment-chevron {
    display: inline-flex;
    color: var(--text-tertiary);
    transition: transform var(--transition-base);
}

.message.user-message .attachment-chevron {
    color: inherit;
}

.attachment-card[open] .attachment-chevron {
    transform: rotate(180deg);
}

.attachment-content {
    border-top: 1px solid var(--border-color);
    background: var(--surface-1);
    padding: 0;
}

.message.user-message .attachment-content {
    background: rgba(255, 255, 255, 0.1);
    border-top: 1px solid rgba(255, 255, 255, 0.25);
}

.attachment-content pre {
    margin: 0;
    padding: 16px;
    max-height: 320px;
    overflow: auto;
    background: transparent;
    border: none;
    border-radius: 0;
    font-family: var(--font-mono);
    color: var(--text-primary);
}

.attachment-content pre code {
    background: none;
    padding: 0;
}

.message.user-message .attachment-content pre {
    color: inherit;
}

.message-content p + p {
    margin-top: 1em;
}

.message-content code {
    font-family: var(--font-mono);
    background: var(--surface-2);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
}

.message-content pre {
    font-family: var(--font-mono);
    background: var(--surface-2);
    padding: 18px;
    border-radius: var(--radius-md);
    overflow-x: auto;
    border: 1px solid var(--border-color);
}

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

.message-content blockquote {
    margin: 0;
    padding-left: 16px;
    border-left: 3px solid var(--accent);
    color: var(--text-secondary);
}

.message-content ul,
.message-content ol {
    padding-left: 22px;
}

.input-area {
    padding: 18px 24px 24px;
    border-top: 1px solid var(--border-color);
    background: var(--surface-0);
    display: flex;
    flex-direction: column;
    gap: 14px;
    position: sticky;
    bottom: 0;
    z-index: 10;
}

.input-toolbar {
    display: flex;
    align-items: center;
    gap: 10px;
}

.file-upload {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.file-preview {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 10px;
    border-radius: var(--radius-md);
    background: var(--surface-2);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.input-composer {
    display: flex;
    align-items: flex-end;
    gap: 12px;
    background: var(--surface-1);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 12px;
}

.input-composer textarea {
    flex: 1;
    resize: none;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 1rem;
    line-height: 1.5;
    max-height: 260px;
}

.input-composer textarea:focus {
    outline: none;
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border-radius: var(--radius-md);
    font-weight: 500;
    border: 1px solid transparent;
    padding: 10px 14px;
    transition: background var(--transition-base), color var(--transition-base), border var(--transition-base), transform var(--transition-base);
}

.button.primary {
    background: var(--accent);
    color: #ffffff;
    border-color: transparent;
}

.button.primary:hover:not(:disabled) {
    background: var(--accent-strong);
}

.button.secondary {
    background: var(--surface-1);
    border-color: var(--border-color);
}

.button.secondary:hover {
    border-color: var(--accent);
    color: var(--accent-strong);
}

.button.ghost {
    background: transparent;
    border-color: transparent;
    justify-content: flex-start;
    padding: 10px 12px;
    color: var(--text-secondary);
}

.button.ghost:hover {
    color: var(--text-primary);
    background: var(--surface-2);
}

.button.full-width {
    width: 100%;
}

.icon-button {
    width: 36px;
    height: 36px;
    border-radius: 999px;
    border: 1px solid transparent;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--surface-1);
    color: var(--text-secondary);
    transition: background var(--transition-base), border var(--transition-base), color var(--transition-base), transform var(--transition-base);
}

.icon-button:hover {
    border-color: var(--border-color);
    background: var(--surface-2);
    color: var(--text-primary);
}

.icon-button.danger {
    background: var(--danger-soft);
    color: var(--danger);
    border-color: rgba(225, 29, 72, 0.24);
}

.icon-button.danger:hover {
    background: rgba(225, 29, 72, 0.18);
}

.drawer {
    position: fixed;
    top: 0;
    right: 0;
    width: min(420px, 90vw);
    height: 100vh;
    background: var(--surface-0);
    border-left: 1px solid var(--border-color);
    box-shadow: -16px 0 40px rgba(15, 23, 42, 0.16);
    transform: translateX(110%);
    transition: transform 280ms ease;
    display: flex;
    flex-direction: column;
    z-index: 50;
}

.drawer.visible {
    transform: translateX(0);
}

.drawer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
}

.drawer-content {
    padding: 24px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.settings-group {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.setting-item {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.setting-control {
    display: grid;
    grid-template-columns: 1fr 80px;
    gap: 12px;
    align-items: center;
}

.setting-control input[type="number"] {
    width: 100%;
    padding: 8px 10px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    background: var(--surface-1);
    color: var(--text-primary);
}

.setting-control input[type="range"] {
    width: 100%;
}

.shortcut-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.shortcut-list li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--surface-1);
    border-radius: var(--radius-md);
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.shortcut-list span {
    font-size: 0.95rem;
}

.modal {
    position: fixed;
    inset: 0;
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 60;
}

.modal.visible {
    display: flex;
}

.modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(15, 23, 42, 0.55);
    backdrop-filter: blur(6px);
}

.modal-content {
    position: relative;
    width: min(760px, 92vw);
    max-height: 84vh;
    background: var(--surface-0);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow-lg);
    display: flex;
    flex-direction: column;
    gap: 24px;
    z-index: 2;
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.modal-body {
    display: flex;
    flex-direction: column;
    gap: 18px;
    overflow-y: auto;
}

.search-container {
    position: relative;
}

.search-container input {
    width: 100%;
    padding: 10px 14px 10px 42px;
    border-radius: var(--radius-lg);
    background: var(--surface-1);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.search-container i {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    width: 18px;
    height: 18px;
    color: var(--text-tertiary);
}

.model-grid {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
}

.model-card {
    border-radius: var(--radius-lg);
    padding: 16px;
    background: var(--surface-1);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 10px;
    transition: transform var(--transition-base), border var(--transition-base), box-shadow var(--transition-base);
    cursor: pointer;
}

.model-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent);
    box-shadow: var(--shadow-sm);
}

.model-card .model-card-name {
    font-weight: 600;
    color: var(--text-primary);
}

.model-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
}

.model-card-subtitle {
    font-size: 0.85rem;
    color: var(--text-secondary);
    white-space: nowrap;
}

.quant-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.quant-chip {
    border-radius: 999px;
    border: 1px solid var(--border-color);
    background: var(--surface-0);
    color: var(--text-secondary);
    padding: 8px 12px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: background var(--transition-base), border var(--transition-base), color var(--transition-base), transform var(--transition-base);
}

.quant-chip:hover {
    background: var(--accent-soft);
    border-color: rgba(37, 99, 235, 0.35);
    color: var(--accent-strong);
    transform: translateY(-1px);
}

.quant-chip.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #ffffff;
    box-shadow: var(--shadow-sm);
}

.model-card.hidden {
    display: none;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 12px;
}

.context-menu {
    position: absolute;
    min-width: 200px;
    background: var(--surface-0);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    padding: 6px;
    z-index: 80;
}

.context-menu ul {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.context-menu li {
    padding: 8px 10px;
    border-radius: var(--radius-sm);
    color: var(--text-primary);
}

.context-menu li:hover {
    background: var(--surface-2);
}

.context-menu .submenu {
    margin-top: 6px;
    padding-left: 10px;
    border-left: 1px solid var(--border-color);
}

#toast-container {
    position: fixed;
    right: 24px;
    bottom: 24px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    z-index: 100;
    pointer-events: none;
}

.toast {
    background: var(--surface-0);
    border-radius: var(--radius-md);
    padding: 12px 16px;
    min-width: 240px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
    pointer-events: auto;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 180ms ease, transform 180ms ease;
}

.toast.visible {
    opacity: 1;
    transform: translateY(0);
}

.toast.success {
    border-color: rgba(74, 222, 128, 0.32);
}

.toast.error {
    border-color: rgba(248, 113, 113, 0.36);
}

.toast-close {
    margin-left: auto;
    display: inline-flex;
    cursor: pointer;
    color: var(--text-tertiary);
}

.toast-close:hover {
    color: var(--text-primary);
}

.sidebar-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.35);
    backdrop-filter: blur(2px);
    z-index: 15;
    display: none;
}

.sidebar-overlay.visible {
    display: block;
}

body.sidebar-open .sidebar {
    transform: translateX(0);
    box-shadow: var(--shadow-lg);
}

body.sidebar-open #sidebar-overlay {
    display: block;
}

body.sidebar-hidden .sidebar {
    flex: 0 0 0;
    width: 0;
    padding-left: 0;
    padding-right: 0;
    border-right-color: transparent;
    opacity: 0;
    pointer-events: none;
    transform: translateX(-24px);
}

body.sidebar-hidden .main-area {
    flex: 1 1 100%;
}

@media (max-width: 1100px) {
    body.sidebar-open {
        overflow: hidden;
    }

    .app-shell {
        overflow: hidden;
    }

    .sidebar {
        position: fixed;
        inset: 0 auto 0 0;
        max-width: clamp(280px, 70vw, 360px);
        transform: translateX(-110%);
        box-shadow: var(--shadow-lg);
    }

    .main-area {
        padding-bottom: 12px;
    }

    .top-bar {
        padding: 16px 20px;
    }

    .model-bar {
        padding: 12px 20px;
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .model-controls {
        width: 100%;
        justify-content: flex-start;
    }

    .chat-container {
        padding: 16px 16px 120px;
    }

    .input-area {
        padding: 16px;
        border-left: none;
        border-right: none;
    }

    .input-composer {
        flex-direction: column;
        align-items: stretch;
    }

    .input-composer textarea {
        min-height: 56px;
    }

    .input-composer .button {
        width: 100%;
    }

    body.sidebar-open {
        overflow: hidden;
    }
}

@media (min-width: 1101px) {
    .sidebar-overlay {
        display: none !important;
        backdrop-filter: none;
        background: transparent;
    }
}

@media (max-width: 720px) {
    :root {
        --sidebar-width: 100vw;
    }

    .top-bar-actions {
        gap: 8px;
    }

    .quick-prompts {
        padding: 10px 16px;
    }

    .chat-box {
        gap: 12px;
    }

    .message {
        border-radius: var(--radius-md);
        padding: 14px 16px;
    }

    .message-actions {
        top: 8px;
        right: 8px;
    }

    .drawer {
        width: min(100vw, 420px);
    }
}

body.dark-mode .icon-button,
body.dark-mode .button.secondary,
body.dark-mode .button.ghost {
    background: rgba(255, 255, 255, 0.04);
    border-color: rgba(255, 255, 255, 0.06);
    color: var(--text-secondary);
}

body.dark-mode .button.ghost:hover,
body.dark-mode .icon-button:hover {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-primary);
}

body.dark-mode .input-composer {
    background: rgba(255, 255, 255, 0.04);
}

body.dark-mode .message-content code,
body.dark-mode .message-content pre {
    background: rgba(255, 255, 255, 0.06);
}

body.dark-mode .chip {
    background: rgba(255, 255, 255, 0.05);
}

body.dark-mode .chip:hover {
    background: rgba(96, 165, 250, 0.18);
}

body.dark-mode .file-preview {
    background: rgba(148, 163, 184, 0.18);
}

.empty-conversations-message,
.empty-folders-message {
    padding: 10px 12px;
    border-radius: var(--radius-md);
    background: var(--surface-1);
    color: var(--text-tertiary);
    border: 1px dashed var(--border-color);
    font-size: 0.9rem;
}

.chat-history-item {
    display: flex;
    align-items: center;
    gap: 10px;
}

.chat-item-actions {
    margin-left: auto;
    display: inline-flex;
    gap: 6px;
}

.chat-options-button {
    width: 28px;
    height: 28px;
    border-radius: 999px;
    display: grid;
    place-items: center;
    border: 1px solid transparent;
    background: transparent;
    color: var(--text-tertiary);
    transition: background var(--transition-base), border var(--transition-base), color var(--transition-base);
}

.chat-options-button:hover {
    background: var(--surface-2);
    border-color: var(--border-color);
    color: var(--text-secondary);
}

.chat-name-input {
    font: inherit;
    padding: 6px 8px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--accent);
    background: var(--surface-0);
    color: var(--text-primary);
}

.folder-item {
    border-radius: var(--radius-md);
    padding: 10px 12px;
    border: 1px solid transparent;
    background: var(--surface-1);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.folder-item.open {
    border-color: var(--border-color);
    background: var(--surface-2);
}

.chat-list-in-folder {
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-top: 8px;
    padding-left: 28px;
    overflow: hidden;
    transition: max-height 220ms ease;
}

.chat-list-in-folder:not(.open) {
    max-height: 0 !important;
}

.folder-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    cursor: pointer;
    color: var(--text-secondary);
}

.folder-header:hover {
    color: var(--text-primary);
}

.folder-contents {
    display: none;
    flex-direction: column;
    gap: 6px;
    margin-top: 8px;
}

.folder-item.open .folder-contents {
    display: flex;
}

.folder-item .folder-actions {
    display: inline-flex;
    gap: 6px;
}
#model-selection,
#load-button {
    position: absolute;
    width: 0;
    height: 0;
    overflow: hidden;
}