:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    
    --text-primary: #111827;
    --text-secondary: #6b7280;
    --text-tertiary: #9ca3af;
    
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    --transition: all 0.2s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    /* Improve touch interactions on mobile */
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Header */
.header {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.logo-icon {
    font-size: 2rem;
}

.nav {
    display: flex;
    gap: 0.5rem;
}

.nav-btn {
    padding: 0.5rem 1.25rem;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    /* Better mobile touch target */
    min-height: 44px;
    touch-action: manipulation;
    user-select: none;
    -webkit-user-select: none;
}

.nav-btn:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.nav-btn:active {
    transform: scale(0.97);
}

.nav-btn.active {
    background-color: var(--primary-color);
    color: white;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.status-indicator {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--secondary-color);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* Main Content */
.main-content {
    padding: 2rem 0;
    height: calc(100vh - 80px);
    overflow: hidden;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Chat Layout */
.chat-layout {
    display: grid;
    grid-template-columns: 320px 1fr;
    gap: 1.5rem;
    height: calc(100vh - 140px);
}

/* Sidebar */
.sidebar {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    overflow-y: auto;
    overflow-x: hidden;
    box-shadow: var(--shadow-md);
}

.sidebar::-webkit-scrollbar {
    width: 8px;
}

.sidebar::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 4px;
}

.sidebar::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.sidebar::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

.sidebar-section {
    margin-bottom: 2rem;
}

.sidebar-section:last-child {
    margin-bottom: 0;
}

.sidebar-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

/* Stats */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

.stat-card {
    background-color: var(--bg-secondary);
    padding: 1rem;
    border-radius: var(--radius-md);
    text-align: center;
}

.stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* Upload Area */
.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem 1rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
}

.upload-area:hover {
    border-color: var(--primary-color);
    background-color: var(--bg-secondary);
}

.upload-area.drag-over {
    border-color: var(--primary-color);
    background-color: var(--primary-light);
    background-opacity: 0.1;
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 0.5rem;
}

.upload-text {
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.upload-subtext {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.upload-info {
    margin-top: 0.75rem;
    text-align: center;
    color: var(--text-tertiary);
    font-size: 0.75rem;
}

/* Upload List */
.upload-list {
    max-height: 300px;
    overflow-y: auto;
}

.upload-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    background-color: var(--bg-secondary);
    border-radius: var(--radius-md);
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

.upload-item-icon {
    font-size: 1.25rem;
}

.upload-item-info {
    flex: 1;
    min-width: 0;
}

.upload-item-name {
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.upload-item-time {
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

.upload-item-chunks {
    font-size: 0.7rem;
    color: var(--primary-color);
    font-weight: 500;
    margin-top: 0.15rem;
}

.upload-item-status {
    font-size: 1rem;
}

/* Chat Area */
.chat-area {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-md);
    height: 100%;
    overflow: hidden;
}

.chat-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.chat-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
    flex-shrink: 0;
}

.chat-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 1.5rem;
    min-height: 0;
}

.chat-messages::-webkit-scrollbar {
    width: 8px;
}

.chat-messages::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 4px;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

/* Welcome Message */
.welcome-message {
    max-width: 600px;
    margin: 2rem auto;
    text-align: center;
}

.welcome-message h2 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.welcome-message p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.quick-tips {
    background-color: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    text-align: left;
}

.quick-tips h4 {
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.quick-tips ul {
    list-style-position: inside;
    color: var(--text-secondary);
}

.quick-tips li {
    margin-bottom: 0.5rem;
}

/* Chat Messages */
.message {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
}

.message.user .message-avatar {
    background-color: var(--primary-color);
    color: white;
}

.message.assistant .message-avatar {
    background-color: var(--secondary-color);
}

.message-content {
    flex: 1;
    min-width: 0;
}

.message-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.message-author {
    font-weight: 600;
    color: var(--text-primary);
}

.message-time {
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

.message-text {
    color: var(--text-primary);
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.message-sources {
    margin-top: 0.75rem;
    padding: 0.75rem;
    background-color: var(--bg-secondary);
    border-radius: var(--radius-md);
    border-left: 3px solid var(--primary-color);
}

.message-sources-title {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.message-sources-list {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.message.typing .message-text {
    display: flex;
    gap: 0.25rem;
}

.typing-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--text-tertiary);
    animation: typing 1.4s infinite;
}

.typing-dot:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-dot:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% {
        transform: translateY(0);
    }
    30% {
        transform: translateY(-10px);
    }
}

/* Chat Input */
.chat-input-container {
    border-top: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    flex-shrink: 0;
    background-color: var(--bg-primary);
}

/* Model Selector */
.model-selector {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.model-toggle-btn {
    flex: 1;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.375rem;
    min-height: 40px;
    touch-action: manipulation;
    user-select: none;
}

.model-toggle-btn:hover {
    background-color: var(--bg-tertiary);
    border-color: var(--primary-color);
}

.model-toggle-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.model-toggle-btn:active {
    transform: scale(0.98);
}

.chat-input-wrapper {
    display: flex;
    gap: 0.75rem;
    align-items: flex-end;
}

.chat-input {
    flex: 1;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 0.75rem 1rem;
    font-size: 0.95rem;
    font-family: inherit;
    resize: none;
    max-height: 120px;
    transition: var(--transition);
}

.chat-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.send-btn {
    width: 44px;
    height: 44px;
    border: none;
    background-color: var(--primary-color);
    color: white;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    flex-shrink: 0;
    touch-action: manipulation;
    user-select: none;
    -webkit-user-select: none;
}

.send-btn:hover:not(:disabled) {
    background-color: var(--primary-dark);
    transform: scale(1.05);
}

.send-btn:active:not(:disabled) {
    transform: scale(0.95);
}

.send-btn:disabled {
    background-color: var(--text-tertiary);
    cursor: not-allowed;
}

.input-hint {
    margin-top: 0.5rem;
    font-size: 0.75rem;
    color: var(--text-tertiary);
    text-align: center;
}

/* Buttons */
.btn {
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    /* Better mobile touch target */
    min-height: 44px;
    touch-action: manipulation;
    user-select: none;
    -webkit-user-select: none;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
}

.btn-primary:active {
    transform: scale(0.98);
}

.btn-secondary {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background-color: var(--border-color);
}

.btn-secondary:active {
    transform: scale(0.98);
}

.btn-sm {
    padding: 0.4rem 0.75rem;
    font-size: 0.85rem;
    gap: 0.35rem;
    min-height: 36px;
}

.btn-sm svg {
    width: 14px;
    height: 14px;
}

.btn-danger {
    background-color: var(--danger-color);
    color: white;
    margin-right: 0.5rem;
    margin-top: 0.5rem;
}

.btn-danger:active {
    transform: scale(0.98);
}

.btn-danger:hover {
    background-color: #dc2626;
}

/* Documents */
.documents-container {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow-md);
}

.documents-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.documents-header h2 {
    margin: 0;
}

.documents-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1.5rem;
}

.document-card {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    transition: var(--transition);
    cursor: pointer;
}

.document-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.document-icon {
    font-size: 2.5rem;
    margin-bottom: 0.75rem;
}

.document-name {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    word-break: break-word;
}

.document-meta {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.document-meta > div {
    margin-bottom: 0.25rem;
}

.document-status {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
    margin-top: 0.5rem;
}

.document-status.indexed {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--secondary-color);
}

.document-status.pending {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

/* Settings */
.settings-container {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 2rem;
    max-width: 800px;
    box-shadow: var(--shadow-md);
}

.settings-container h2 {
    margin-bottom: 2rem;
}

.settings-section {
    margin-bottom: 2.5rem;
}

.settings-section h3 {
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.setting-item {
    margin-bottom: 1.5rem;
}

.setting-item label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.setting-item input[type="number"],
.setting-item input[type="range"] {
    width: 100%;
    max-width: 300px;
}

.setting-item small {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-secondary);
}

.about-info {
    background-color: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: var(--radius-md);
}

.about-info p {
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-tertiary);
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 1000;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.toast {
    background-color: white;
    padding: 1rem 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-width: 300px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.toast.success {
    border-left: 4px solid var(--secondary-color);
}

.toast.error {
    border-left: 4px solid var(--danger-color);
}

.toast.info {
    border-left: 4px solid var(--primary-color);
}

.toast-icon {
    font-size: 1.5rem;
}

.toast-message {
    flex: 1;
    color: var(--text-primary);
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.loading-overlay.active {
    display: flex;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

.loading-text {
    color: white;
    margin-top: 1rem;
    font-size: 1.125rem;
}

/* Responsive */

/* Tablet and below */
@media (max-width: 1024px) {
    .chat-layout {
        grid-template-columns: 1fr;
        height: auto;
    }
    
    .sidebar {
        order: 2;
        height: auto;
        max-height: none;
    }
    
    .chat-area {
        order: 1;
        height: 60vh;
        min-height: 400px;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .main-content {
        padding: 1.5rem 0;
    }
}

/* Mobile landscape and below */
@media (max-width: 768px) {
    .header-content {
        flex-wrap: wrap;
        gap: 0.75rem;
        padding: 0.75rem 0;
    }
    
    .logo {
        font-size: 1.25rem;
    }
    
    .logo-icon {
        font-size: 1.5rem;
    }
    
    .nav {
        order: 3;
        width: 100%;
        justify-content: center;
    }
    
    .nav-btn {
        padding: 0.5rem 1rem;
        font-size: 0.875rem;
        flex: 1;
    }
    
    .user-info {
        font-size: 0.8rem;
    }
    
    .container {
        padding: 0 0.75rem;
    }
    
    .main-content {
        padding: 1rem 0;
    }
    
    .chat-layout {
        gap: 1rem;
    }
    
    .chat-area {
        height: 55vh;
        min-height: 350px;
    }
    
    .chat-header {
        padding: 0.75rem 1rem;
    }
    
    .chat-header h2 {
        font-size: 1rem;
    }
    
    .btn-secondary {
        padding: 0.375rem 0.75rem;
        font-size: 0.8rem;
    }
    
    .chat-messages {
        padding: 1rem;
    }
    
    .message {
        gap: 0.75rem;
        margin-bottom: 1.25rem;
    }
    
    .message-avatar {
        width: 32px;
        height: 32px;
        font-size: 1rem;
    }
    
    .chat-input-container {
        padding: 0.75rem 1rem;
    }
    
    .chat-input-wrapper {
        gap: 0.5rem;
    }
    
    .chat-input {
        font-size: 0.9rem;
        padding: 0.625rem 0.875rem;
    }
    
    .send-btn {
        padding: 0.625rem;
        font-size: 1.25rem;
    }
    
    .sidebar {
        padding: 1rem;
    }
    
    .sidebar-section {
        margin-bottom: 1.5rem;
    }
    
    .stats-grid {
        gap: 0.5rem;
    }
    
    .stat-card {
        padding: 0.75rem;
    }
    
    .stat-value {
        font-size: 1.5rem;
    }
    
    .upload-area {
        padding: 1.5rem 0.75rem;
    }
    
    .upload-icon {
        font-size: 2.5rem;
    }
    
    .documents-grid {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }
    
    .document-card {
        padding: 1rem;
    }
    
    .settings-section {
        padding: 1rem;
    }
}

/* Mobile portrait */
@media (max-width: 480px) {
    .header-content {
        padding: 0.5rem 0;
    }
    
    .logo {
        font-size: 1.1rem;
        gap: 0.5rem;
    }
    
    .logo-icon {
        font-size: 1.35rem;
    }
    
    .user-info {
        display: none;
    }
    
    .nav-btn {
        padding: 0.375rem 0.75rem;
        font-size: 0.8rem;
    }
    
    .container {
        padding: 0 0.5rem;
    }
    
    .main-content {
        padding: 0.75rem 0;
    }
    
    .chat-layout {
        gap: 0.75rem;
        height: auto;
    }
    
    .chat-area {
        height: calc(100vh - 200px);
        min-height: 300px;
        border-radius: var(--radius-md);
    }
    
    .chat-header {
        padding: 0.625rem 0.875rem;
    }
    
    .chat-header h2 {
        font-size: 0.9rem;
    }
    
    .btn-secondary {
        padding: 0.25rem 0.5rem;
        font-size: 0.75rem;
    }
    
    .btn-sm {
        padding: 0.25rem 0.5rem;
        font-size: 0.7rem;
    }
    
    .chat-messages {
        padding: 0.75rem;
    }
    
    .message {
        gap: 0.5rem;
        margin-bottom: 1rem;
    }
    
    .message-avatar {
        width: 28px;
        height: 28px;
        font-size: 0.875rem;
    }
    
    .message-text {
        font-size: 0.9rem;
    }
    
    .message-sources {
        padding: 0.625rem;
        font-size: 0.8rem;
    }
    
    .chat-input-container {
        padding: 0.625rem 0.75rem;
    }
    
    .chat-input {
        font-size: 0.85rem;
        padding: 0.5rem 0.75rem;
        max-height: 100px;
    }
    
    .send-btn {
        padding: 0.5rem;
        font-size: 1.1rem;
    }
    
    .sidebar {
        padding: 0.875rem;
    }
    
    .sidebar-title {
        font-size: 0.9rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 0.5rem;
    }
    
    .stat-card {
        padding: 0.625rem;
    }
    
    .stat-value {
        font-size: 1.25rem;
    }
    
    .stat-label {
        font-size: 0.7rem;
    }
    
    .upload-area {
        padding: 1.25rem 0.5rem;
    }
    
    .upload-icon {
        font-size: 2rem;
    }
    
    .upload-text {
        font-size: 0.9rem;
    }
    
    .upload-hint {
        font-size: 0.75rem;
    }
    
    .file-input-label {
        padding: 0.5rem 1rem;
        font-size: 0.85rem;
    }
    
    .upload-list-item {
        padding: 0.75rem;
    }
    
    .upload-item-info h4 {
        font-size: 0.9rem;
    }
    
    .upload-item-meta,
    .upload-item-chunks {
        font-size: 0.75rem;
    }
    
    .document-card {
        padding: 0.875rem;
    }
    
    .document-title {
        font-size: 0.9rem;
    }
    
    .document-meta {
        font-size: 0.75rem;
    }
    
    .settings-section {
        padding: 0.875rem;
        margin-bottom: 1rem;
    }
    
    .settings-section h3 {
        font-size: 0.9rem;
    }
    
    .setting-item label {
        font-size: 0.85rem;
    }
    
    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.85rem;
    }
}

/* Very small screens */
@media (max-width: 360px) {
    .logo span {
        display: none;
    }
    
    .nav {
        gap: 0.25rem;
    }
    
    .nav-btn {
        padding: 0.375rem 0.5rem;
        font-size: 0.75rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .chat-area {
        height: calc(100vh - 180px);
    }
}