/* ============================================
   AI Chatbot - Main Stylesheet
   ============================================ */

/* --------------------------------------------
   CSS Custom Properties (Design Tokens)
   -------------------------------------------- */
:root {
    /* Colors - Background */
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #1c1c1e;
    --bg-elevated: #2c2c2e;
    --bg-hover: #3a3a3c;
    
    /* Colors - Border */
    --border-primary: #333;
    --border-secondary: #38383a;
    --border-light: #48484a;
    
    /* Colors - Text */
    --text-primary: #fff;
    --text-secondary: #e0e0e0;
    --text-muted: #888;
    --text-dim: #666;
    --text-placeholder: #8e8e93;
    
    /* Colors - Accent */
    --accent-blue: #4a7dff;
    --accent-blue-hover: #3a6de8;
    --accent-blue-bright: #0a84ff;
    --accent-green: #28a745;
    --accent-green-hover: #218838;
    --accent-red: #dc3545;
    --accent-red-hover: #c82333;
    --accent-yellow: #ffc107;
    --accent-orange: #ff9500;
    
    /* Colors - Status */
    --status-success-bg: #1f3d1f;
    --status-success-border: #28a745;
    --status-success-text: #d4edda;
    --status-error-bg: #3d1f1f;
    --status-error-border: #dc3545;
    --status-error-text: #f8d7da;
    --status-warning-bg: #3d2e1f;
    --status-warning-border: #ffc107;
    --status-warning-text: #e0e0e0;
    --status-info-bg: #1a2a3a;
    --status-info-border: #2a4a6a;
    --status-info-text: #8ab4f8;
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --font-family-mono: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.8rem;
    --font-size-base: 0.875rem;
    --font-size-md: 1rem;
    --font-size-lg: 1.1rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.75rem;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 20px;
    --spacing-2xl: 24px;
    --spacing-3xl: 32px;
    --spacing-4xl: 48px;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;
    --radius-2xl: 16px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.5);
    
    /* Transitions */
    --transition-fast: 0.1s ease;
    --transition-base: 0.2s ease;
    --transition-slow: 0.3s ease;
    
    /* Layout */
    --container-max-width: 1200px;
    --header-height: 60px;
}

/* --------------------------------------------
   Reset & Base Styles
   -------------------------------------------- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    min-height: 100vh;
    line-height: 1.5;
}

a {
    color: var(--accent-blue);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* --------------------------------------------
   Layout
   -------------------------------------------- */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: var(--spacing-xl);
}

.page-wrapper {
    padding: var(--spacing-xl);
}

/* --------------------------------------------
   Page Header
   -------------------------------------------- */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-3xl);
    padding-bottom: var(--spacing-xl);
    border-bottom: 1px solid var(--border-primary);
}

.page-header h1 {
    font-size: var(--font-size-2xl);
    color: var(--text-primary);
}

.header-actions {
    display: flex;
    gap: 10px;
}

/* --------------------------------------------
   Buttons
   -------------------------------------------- */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: var(--font-size-base);
    font-weight: 500;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    transition: all var(--transition-base);
    line-height: 1.4;
}

.btn:hover {
    text-decoration: none;
}

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

.btn-primary:hover {
    background: var(--accent-blue-hover);
}

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

.btn-secondary:hover {
    background: #444;
}

.btn-success {
    background: var(--accent-green);
    color: white;
}

.btn-success:hover {
    background: var(--accent-green-hover);
}

.btn-danger {
    background: var(--accent-red);
    color: white;
}

.btn-danger:hover {
    background: var(--accent-red-hover);
}

.btn-sm {
    padding: 6px 12px;
    font-size: var(--font-size-xs);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* --------------------------------------------
   Forms
   -------------------------------------------- */
.form-section {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    margin-bottom: var(--spacing-xl);
}

.form-section h2 {
    font-size: var(--font-size-md);
    color: var(--text-muted);
    margin-bottom: var(--spacing-lg);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-group {
    margin-bottom: var(--spacing-xl);
}

.form-group:last-child {
    margin-bottom: 0;
}

.form-group label {
    display: block;
    margin-bottom: var(--spacing-sm);
    color: #ccc;
    font-size: var(--font-size-base);
    font-weight: 500;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-secondary);
    font-size: var(--font-size-base);
    font-family: inherit;
    transition: border-color var(--transition-base);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent-blue);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

.form-group .help-text {
    color: var(--text-dim);
    font-size: var(--font-size-xs);
    margin-top: 6px;
}

.form-row {
    display: flex;
    gap: var(--spacing-lg);
}

.form-row .form-group {
    flex: 1;
    margin-bottom: var(--spacing-md);
}

.form-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--border-primary);
    margin-top: var(--spacing-xl);
}

/* --------------------------------------------
   Tables
   -------------------------------------------- */
.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

th, td {
    padding: 14px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border-primary);
}

th {
    background: #252525;
    color: var(--text-muted);
    font-weight: 500;
    font-size: var(--font-size-xs);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

tr:hover {
    background: #222;
}

tr:last-child td {
    border-bottom: none;
}

/* --------------------------------------------
   Cards
   -------------------------------------------- */
.card {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    border: 1px solid var(--border-primary);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-md);
}

.card-title {
    font-weight: 600;
    font-size: var(--font-size-lg);
    color: var(--text-primary);
}

.card-meta {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.card-actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* --------------------------------------------
   Modals
   -------------------------------------------- */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

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

.modal {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    max-width: 500px;
    width: 90%;
    border: 1px solid var(--border-primary);
}

.modal h2,
.modal h3 {
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

.modal p {
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
    line-height: 1.5;
}

.modal-actions {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    margin-top: var(--spacing-xl);
}

/* --------------------------------------------
   Status Badges
   -------------------------------------------- */
.badge {
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 500;
    display: inline-block;
}

.badge-success {
    background: #166534;
    color: #bbf7d0;
}

.badge-danger {
    background: #991b1b;
    color: #fecaca;
}

.badge-warning {
    background: #92400e;
    color: #fde68a;
}

.badge-info {
    background: var(--accent-blue);
    color: white;
}

/* --------------------------------------------
   Alerts / Messages
   -------------------------------------------- */
.alert {
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-xl);
    font-size: var(--font-size-base);
}

.alert-success {
    background: var(--status-success-bg);
    border: 1px solid var(--status-success-border);
    color: var(--status-success-text);
}

.alert-error {
    background: var(--status-error-bg);
    border: 1px solid var(--status-error-border);
    color: var(--status-error-text);
}

.alert-warning {
    background: var(--status-warning-bg);
    border: 1px solid var(--status-warning-border);
    color: var(--status-warning-text);
}

.alert-info {
    background: var(--status-info-bg);
    border: 1px solid var(--status-info-border);
    color: var(--status-info-text);
}

.alert code {
    background: var(--bg-primary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-family: var(--font-family-mono);
}

/* --------------------------------------------
   Empty & Loading States
   -------------------------------------------- */
.empty-state {
    text-align: center;
    padding: var(--spacing-4xl) var(--spacing-xl);
    color: var(--text-dim);
}

.empty-state h3 {
    margin-bottom: 10px;
    color: var(--text-muted);
}

.empty-state p {
    margin-bottom: var(--spacing-xl);
}

.loading {
    text-align: center;
    padding: var(--spacing-3xl);
    color: var(--text-dim);
}

/* --------------------------------------------
   Utility Classes
   -------------------------------------------- */
.text-muted {
    color: var(--text-muted);
}

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

.text-accent {
    color: var(--accent-blue);
}

.text-success {
    color: var(--accent-green);
}

.text-danger {
    color: var(--accent-red);
}

.text-warning {
    color: var(--accent-yellow);
}

.text-sm {
    font-size: var(--font-size-sm);
}

.text-xs {
    font-size: var(--font-size-xs);
}

.font-mono {
    font-family: var(--font-family-mono);
}

.font-semibold {
    font-weight: 600;
}

.cursor-pointer {
    cursor: pointer;
}

.truncate {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Flex utilities */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.items-center {
    align-items: center;
}

.justify-between {
    justify-content: space-between;
}

.justify-center {
    justify-content: center;
}

.gap-sm {
    gap: var(--spacing-sm);
}

.gap-md {
    gap: var(--spacing-md);
}

.gap-lg {
    gap: var(--spacing-lg);
}

/* Margin utilities */
.mt-md {
    margin-top: var(--spacing-md);
}

.mt-lg {
    margin-top: var(--spacing-lg);
}

.mb-md {
    margin-bottom: var(--spacing-md);
}

.mb-lg {
    margin-bottom: var(--spacing-lg);
}

/* --------------------------------------------
   Clickable Items
   -------------------------------------------- */
.clickable-name {
    color: var(--accent-blue);
    font-weight: 500;
    cursor: pointer;
}

.clickable-name:hover {
    text-decoration: underline;
}

/* --------------------------------------------
   Timestamp
   -------------------------------------------- */
.timestamp {
    color: var(--text-dim);
    font-size: var(--font-size-sm);
}

/* --------------------------------------------
   Item Lists (for edit pages)
   -------------------------------------------- */
.item-list {
    margin-top: var(--spacing-lg);
}

.item-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.item-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.item-header h3 {
    font-size: var(--font-size-base);
    color: var(--accent-blue);
}

.add-item-btn {
    width: 100%;
    padding: var(--spacing-lg);
    border: 2px dashed var(--border-primary);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--text-dim);
    cursor: pointer;
    font-size: var(--font-size-base);
    transition: all var(--transition-base);
}

.add-item-btn:hover {
    border-color: var(--accent-blue);
    color: var(--accent-blue);
}

/* --------------------------------------------
   Dropdown Menus
   -------------------------------------------- */
.dropdown {
    position: relative;
}

.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: var(--spacing-sm);
    background: var(--bg-elevated);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-lg);
    min-width: 200px;
    box-shadow: var(--shadow-md);
    z-index: 1000;
}

.dropdown-menu.active {
    display: block;
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    color: var(--text-primary);
    text-decoration: none;
    transition: background var(--transition-base);
    cursor: pointer;
    border: none;
    background: none;
    width: 100%;
    font-size: var(--font-size-base);
}

.dropdown-item:hover {
    background: var(--bg-hover);
    text-decoration: none;
}

.dropdown-divider {
    height: 1px;
    background: var(--border-secondary);
    margin: var(--spacing-sm) 0;
}

/* --------------------------------------------
   Backdrop
   -------------------------------------------- */
.backdrop {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 99;
}

.backdrop.active {
    display: block;
}

/* --------------------------------------------
   Scrollbar Styling
   -------------------------------------------- */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--border-secondary);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--border-light);
}

/* --------------------------------------------
   Responsive
   -------------------------------------------- */
@media (max-width: 768px) {
    .page-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-lg);
    }
    
    .header-actions {
        width: 100%;
        flex-wrap: wrap;
    }
    
    .form-row {
        flex-direction: column;
    }
    
    .modal {
        margin: var(--spacing-lg);
        width: calc(100% - var(--spacing-3xl));
    }
    
    table {
        font-size: var(--font-size-sm);
    }
    
    th, td {
        padding: 10px 12px;
    }
}