/* ===================================
   CSS Variables & Theme
   =================================== */
:root {
    /* Material Design Colors */
    --primary-color: #1976d2;
    --primary-dark: #1565c0;
    --primary-light: #42a5f5;
    --secondary-color: #dc004e;
    --accent-color: #ff4081;
    
    /* Neutral Colors */
    --background: #fafafa;
    --surface: #ffffff;
    --error: #f44336;
    --success: #4caf50;
    --warning: #ff9800;
    --info: #2196f3;
    
    /* Text Colors */
    --text-primary: rgba(0, 0, 0, 0.87);
    --text-secondary: rgba(0, 0, 0, 0.60);
    --text-disabled: rgba(0, 0, 0, 0.38);
    --text-hint: rgba(0, 0, 0, 0.38);
    
    /* Border & Divider */
    --divider: rgba(0, 0, 0, 0.12);
    --border-color: rgba(0, 0, 0, 0.12);
    
    /* Shadows */
    --shadow-1: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    --shadow-2: 0 3px 6px rgba(0,0,0,0.15), 0 2px 4px rgba(0,0,0,0.12);
    --shadow-3: 0 10px 20px rgba(0,0,0,0.15), 0 3px 6px rgba(0,0,0,0.10);
    --shadow-4: 0 15px 25px rgba(0,0,0,0.15), 0 5px 10px rgba(0,0,0,0.05);
    
    /* Typography */
    --font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: var(--font-family);
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-dark);
}

/* ===================================
   Navigation Bar
   =================================== */
.navbar {
    background: var(--surface);
    box-shadow: var(--shadow-2);
    position: sticky;
    top: 0;
    z-index: 1000;
    height: 64px;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 20px;
    font-weight: 500;
    color: var(--text-primary);
}

.nav-brand .material-icons {
    color: var(--primary-color);
    font-size: 32px;
}

.nav-menu {
    display: flex;
    gap: var(--spacing-sm);
}

.nav-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.nav-link:hover {
    background: rgba(0, 0, 0, 0.04);
    color: var(--primary-color);
}

.nav-link .material-icons {
    font-size: 20px;
}

/* ===================================
   Main Content Area
   =================================== */
.main-content {
    min-height: calc(100vh - 64px - 200px);
    padding: var(--spacing-xl) var(--spacing-lg);
}

/* ===================================
   Page Container
   =================================== */
.page-container {
    max-width: 1000px;
    margin: 0 auto;
}

.content-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-1);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
}

.page-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--divider);
}

.page-icon {
    font-size: 48px !important;
    color: var(--primary-color);
}

.page-header h1 {
    font-size: 32px;
    font-weight: 400;
    color: var(--text-primary);
}

.content-section {
    margin-bottom: var(--spacing-xl);
}

.content-section h2 {
    font-size: 24px;
    font-weight: 400;
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

.content-section h3 {
    font-size: 20px;
    font-weight: 500;
    margin-bottom: var(--spacing-md);
}

.content-section h4 {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
}

.content-section p {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===================================
   Chat Interface
   =================================== */
.chat-page {
    max-width: 1400px;
    margin: 0 auto;
}

.chat-wrapper {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: var(--spacing-lg);
    align-items: start;
}

.chat-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    height: calc(100vh - 180px);
}

/* Chat Header */
.chat-header {
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chat-header-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.chat-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
}

.chat-avatar .material-icons {
    font-size: 28px;
}

.chat-header-info h2 {
    font-size: 20px;
    font-weight: 500;
    margin-bottom: 2px;
}

.status-text {
    font-size: 14px;
    opacity: 0.9;
}

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

/* Messages Container */
.messages-container {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-lg);
    background: #f5f5f5;
}

.welcome-message {
    text-align: center;
    padding: var(--spacing-xxl) var(--spacing-lg);
    max-width: 600px;
    margin: 0 auto;
}

.welcome-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-lg);
    background: var(--primary-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.welcome-icon .material-icons {
    font-size: 48px;
    color: white;
}

.welcome-message h3 {
    font-size: 24px;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

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

.feature-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    text-align: left;
    max-width: 400px;
    margin: 0 auto;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-secondary);
}

.feature-item .material-icons {
    color: var(--success);
    font-size: 20px;
}

/* Message Bubbles */
.message {
    margin-bottom: var(--spacing-lg);
    display: flex;
    animation: fadeInUp 0.3s ease;
}

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

.message.user {
    justify-content: flex-end;
}

.message.assistant {
    justify-content: flex-start;
}

.message-bubble {
    max-width: 70%;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-1);
    position: relative;
}

.message.assistant .message-bubble {
    background: white;
    border-bottom-left-radius: var(--radius-sm);
}

.message.user .message-bubble {
    background: var(--primary-color);
    color: white;
    border-bottom-right-radius: var(--radius-sm);
}

.message-label {
    font-size: 12px;
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
    opacity: 0.7;
}

.message-content {
    line-height: 1.5;
    word-wrap: break-word;
}

.message-time {
    font-size: 11px;
    opacity: 0.6;
    margin-top: var(--spacing-xs);
}

/* Input Area */
.input-area {
    border-top: 1px solid var(--divider);
    padding: var(--spacing-lg);
    background: var(--surface);
}

.input-wrapper {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    background: var(--background);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xs);
    border: 2px solid transparent;
    transition: border-color var(--transition-fast);
}

.input-wrapper:focus-within {
    border-color: var(--primary-color);
}

.input-wrapper input {
    flex: 1;
    border: none;
    outline: none;
    background: transparent;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 15px;
    font-family: var(--font-family);
    color: var(--text-primary);
}

.input-wrapper input::placeholder {
    color: var(--text-hint);
}

/* Action Buttons */
.action-buttons {
    display: flex;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--surface);
    border-top: 1px solid var(--divider);
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 10px 24px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    font-family: var(--font-family);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-1);
    text-decoration: none;
}

.btn:hover {
    box-shadow: var(--shadow-2);
    transform: translateY(-1px);
}

.btn:active {
    transform: translateY(0);
    box-shadow: var(--shadow-1);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}

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

.btn-primary:hover:not(:disabled) {
    background: var(--primary-dark);
}

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

.btn-secondary:hover:not(:disabled) {
    background: var(--background);
}

.btn-large {
    padding: 14px 32px;
    font-size: 16px;
}

.btn .material-icons {
    font-size: 20px;
}

.icon-btn {
    width: 40px;
    height: 40px;
    border: none;
    background: transparent;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background var(--transition-fast);
    color: inherit;
}

.icon-btn:hover {
    background: rgba(0, 0, 0, 0.08);
}

.icon-btn .material-icons {
    font-size: 20px;
}

.chat-header .icon-btn {
    color: white;
}

.chat-header .icon-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

/* ===================================
   Info Panel
   =================================== */
.info-panel {
    position: sticky;
    top: 80px;
}

.info-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-1);
    overflow: hidden;
}

.info-header {
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.info-header h3 {
    font-size: 18px;
    font-weight: 500;
}

.info-header .icon-btn {
    color: white;
}

.info-content {
    padding: var(--spacing-lg);
    max-height: calc(100vh - 280px);
    overflow-y: auto;
}

.info-content h4 {
    font-size: 14px;
    font-weight: 500;
    margin: var(--spacing-lg) 0 var(--spacing-sm);
    color: var(--text-primary);
}

.info-content h4:first-child {
    margin-top: 0;
}

.info-list {
    list-style: none;
    margin-bottom: var(--spacing-lg);
}

.info-list li {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-xs) 0;
    color: var(--text-secondary);
}

.info-list .material-icons {
    font-size: 18px;
    color: var(--success);
}

.config-info {
    background: var(--background);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
}

.config-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--divider);
}

.config-item:last-child {
    border-bottom: none;
}

.config-item strong {
    font-weight: 500;
    color: var(--text-primary);
}

.config-item span {
    color: var(--text-secondary);
    font-size: 14px;
}

.status-indicator {
    display: inline-block;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success);
    margin-right: var(--spacing-xs);
    animation: pulse 2s infinite;
}

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

/* ===================================
   Features Grid
   =================================== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.feature-card {
    background: var(--surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    transition: all var(--transition-normal);
}

.feature-card:hover {
    box-shadow: var(--shadow-2);
    transform: translateY(-4px);
}

.feature-icon {
    font-size: 48px !important;
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    margin: 0;
}

/* ===================================
   Steps Container
   =================================== */
.steps-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.step-item {
    display: flex;
    gap: var(--spacing-lg);
    align-items: flex-start;
}

.step-number {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--primary-color);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    font-weight: 500;
    flex-shrink: 0;
}

.step-content h3 {
    font-size: 18px;
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
}

.step-content p {
    color: var(--text-secondary);
    margin: 0;
}

/* ===================================
   Badges
   =================================== */
.badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
    text-transform: uppercase;
}

.badge-free {
    background: #e8f5e9;
    color: #2e7d32;
}

.badge-paid {
    background: #fff3e0;
    color: #e65100;
}

.badge-local {
    background: #e3f2fd;
    color: #1565c0;
}

.badge-cloud {
    background: #f3e5f5;
    color: #6a1b9a;
}

.badge-recommended {
    background: #e0f2f1;
    color: #00695c;
}

.badge-fast {
    background: #fff9c4;
    color: #f57f17;
}

.badge-advanced {
    background: #fce4ec;
    color: #c2185b;
}

.badges {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

/* ===================================
   Alerts
   =================================== */
.alert {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
}

.alert .material-icons {
    font-size: 24px;
    flex-shrink: 0;
}

.alert-warning {
    background: #fff3e0;
    border-left: 4px solid var(--warning);
}

.alert-warning .material-icons {
    color: var(--warning);
}

.alert strong {
    display: block;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

.alert p {
    margin: 0;
    color: var(--text-secondary);
}

/* ===================================
   Code Blocks
   =================================== */
.code-block {
    background: #263238;
    border-radius: var(--radius-md);
    overflow: hidden;
    margin-bottom: var(--spacing-lg);
}

.code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    background: #37474f;
    color: white;
    font-size: 14px;
}

.code-block pre {
    margin: 0;
    padding: var(--spacing-lg);
    overflow-x: auto;
}

.code-block code {
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 14px;
    line-height: 1.6;
    color: #aed581;
}

code {
    background: var(--background);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 14px;
    color: var(--secondary-color);
}

/* ===================================
   Tabs
   =================================== */
.tabs {
    display: flex;
    gap: var(--spacing-xs);
    border-bottom: 2px solid var(--divider);
    margin-bottom: var(--spacing-lg);
    overflow-x: auto;
}

.tab-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-family: var(--font-family);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.tab-btn:hover {
    background: rgba(0, 0, 0, 0.04);
    color: var(--text-primary);
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab-btn .material-icons {
    font-size: 20px;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* ===================================
   Provider Cards
   =================================== */
.provider-card {
    background: var(--background);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
}

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

.provider-header h3 {
    font-size: 20px;
    font-weight: 500;
}

.provider-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--background);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-sm);
}

.provider-item strong {
    flex: 1;
}

.providers-list {
    display: flex;
    flex-direction: column;
}

/* ===================================
   Configuration Display
   =================================== */
.config-display {
    background: var(--background);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.config-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--divider);
}

.config-row:last-child {
    border-bottom: none;
}

.config-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.config-label .material-icons {
    color: var(--primary-color);
}

.config-value {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.config-value code {
    background: var(--surface);
    padding: var(--spacing-xs) var(--spacing-sm);
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 4px 12px;
    border-radius: 12px;
    background: #e8f5e9;
    color: #2e7d32;
    font-size: 14px;
    font-weight: 500;
}

.status-badge .material-icons {
    font-size: 18px;
}

/* ===================================
   Snackbar / Toast
   =================================== */
.snackbar {
    position: fixed;
    bottom: -100px;
    left: 50%;
    transform: translateX(-50%);
    background: #323232;
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-3);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    min-width: 300px;
    max-width: 600px;
    z-index: 2000;
    transition: bottom var(--transition-normal);
}

.snackbar.show {
    bottom: var(--spacing-lg);
}

.snackbar-message {
    flex: 1;
}

.snackbar .icon-btn {
    color: white;
}

/* ===================================
   Loading Overlay
   =================================== */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: var(--spacing-lg);
    z-index: 3000;
}

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

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.loading-overlay p {
    color: white;
    font-size: 16px;
}

/* ===================================
   Footer
   =================================== */
.footer {
    background: #263238;
    color: rgba(255, 255, 255, 0.87);
    margin-top: var(--spacing-xxl);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-xxl) var(--spacing-lg);
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
}

.footer-section h3,
.footer-section h4 {
    color: white;
    margin-bottom: var(--spacing-md);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.6;
}

.footer-section p.small {
    font-size: 13px;
}

.footer-section a {
    display: block;
    color: rgba(255, 255, 255, 0.87);
    margin-bottom: var(--spacing-sm);
    transition: color var(--transition-fast);
}

.footer-section a:hover {
    color: var(--primary-light);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    padding: var(--spacing-lg);
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
}

.footer-bottom p {
    margin: 0;
    font-size: 14px;
}

/* ===================================
   Action Center
   =================================== */
.action-center {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--divider);
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 1024px) {
    .chat-wrapper {
        grid-template-columns: 1fr;
    }
    
    .info-panel {
        display: none;
    }
}

@media (max-width: 768px) {
    .nav-container {
        padding: 0 var(--spacing-md);
    }
    
    .nav-link span:not(.material-icons) {
        display: none;
    }
    
    .brand-text {
        font-size: 16px;
    }
    
    .main-content {
        padding: var(--spacing-lg) var(--spacing-md);
    }
    
    .content-card {
        padding: var(--spacing-lg);
    }
    
    .page-header h1 {
        font-size: 24px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .action-center {
        flex-direction: column;
    }
    
    .action-buttons {
        flex-direction: column;
    }
    
    .message-bubble {
        max-width: 85%;
    }
    
    .footer-container {
        grid-template-columns: 1fr;
        padding: var(--spacing-lg);
    }
}

@media (max-width: 480px) {
    .navbar {
        height: 56px;
    }
    
    .nav-brand .material-icons {
        font-size: 24px;
    }
    
    .brand-text {
        font-size: 14px;
    }
    
    .chat-card {
        height: calc(100vh - 120px);
    }
    
    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* ===================================
   Utility Classes
   =================================== */
.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

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

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

.hidden {
    display: none !important;
}