/* =====================================================
   DESIGN SYSTEM - Hệ Thống Phân Tích Hội Thoại
   Premium Dark Mode UI
   ===================================================== */

/* ========================
   Google Fonts
   ======================== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ========================
   CSS Variables / Design Tokens
   ======================== */
:root {
    /* Color Palette - Deep Space Theme */
    --color-bg-primary: #0a0e1a;
    --color-bg-secondary: #111827;
    --color-bg-tertiary: #1a2235;
    --color-bg-card: #151d2e;
    --color-bg-card-hover: #1c2640;
    --color-bg-input: #0d1321;
    --color-bg-sidebar: #0c1120;
    --color-bg-overlay: rgba(0, 0, 0, 0.6);

    /* Accent Colors */
    --color-primary: #6366f1;
    --color-primary-light: #818cf8;
    --color-primary-dark: #4f46e5;
    --color-primary-glow: rgba(99, 102, 241, 0.15);
    --color-primary-glow-strong: rgba(99, 102, 241, 0.3);

    --color-secondary: #8b5cf6;
    --color-accent: #06b6d4;
    --color-accent-light: #22d3ee;

    /* Semantic Colors */
    --color-success: #10b981;
    --color-success-bg: rgba(16, 185, 129, 0.1);
    --color-warning: #f59e0b;
    --color-warning-bg: rgba(245, 158, 11, 0.1);
    --color-error: #ef4444;
    --color-error-bg: rgba(239, 68, 68, 0.1);
    --color-info: #3b82f6;
    --color-info-bg: rgba(59, 130, 246, 0.1);

    /* Text Colors */
    --color-text-primary: #f1f5f9;
    --color-text-secondary: #94a3b8;
    --color-text-tertiary: #64748b;
    --color-text-muted: #475569;
    --color-text-inverse: #0a0e1a;

    /* Border Colors */
    --color-border: rgba(148, 163, 184, 0.1);
    --color-border-hover: rgba(148, 163, 184, 0.2);
    --color-border-focus: var(--color-primary);

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #6366f1, #8b5cf6);
    --gradient-accent: linear-gradient(135deg, #06b6d4, #3b82f6);
    --gradient-success: linear-gradient(135deg, #10b981, #06b6d4);
    --gradient-card: linear-gradient(135deg, rgba(99, 102, 241, 0.05), rgba(139, 92, 246, 0.05));
    --gradient-glass: linear-gradient(135deg, rgba(255, 255, 255, 0.05), rgba(255, 255, 255, 0.02));
    --gradient-sidebar: linear-gradient(180deg, #0c1120 0%, #111827 100%);

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 50px -10px rgba(0, 0, 0, 0.6);
    --shadow-glow: 0 0 30px rgba(99, 102, 241, 0.15);
    --shadow-glow-strong: 0 0 50px rgba(99, 102, 241, 0.25);

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;

    --font-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;

    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

    /* Layout */
    --sidebar-width: 280px;
    --sidebar-collapsed-width: 72px;
    --header-height: 64px;
    --content-max-width: 1400px;

    /* Z-Index */
    --z-sidebar: 40;
    --z-header: 30;
    --z-overlay: 50;
    --z-modal: 60;
    --z-toast: 70;
}

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

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

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-normal);
    line-height: var(--line-height-normal);
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    overflow-x: hidden;
    min-height: 100vh;
}

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

img { max-width: 100%; display: block; }

/* ========================
   Scrollbar
   ======================== */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
    background: var(--color-text-tertiary);
    border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover { background: var(--color-text-secondary); }

/* ========================
   Layout: App Shell
   ======================== */
.app-container {
    display: flex;
    min-height: 100vh;
}

/* ========================
   Sidebar
   ======================== */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: var(--gradient-sidebar);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    z-index: var(--z-sidebar);
    transition: width var(--transition-base), transform var(--transition-base);
    overflow: hidden;
}

.sidebar-header {
    padding: var(--space-6);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-height: var(--header-height);
}

.sidebar-logo {
    width: 36px;
    height: 36px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    color: white;
    flex-shrink: 0;
    box-shadow: var(--shadow-glow);
}

.sidebar-brand {
    display: flex;
    flex-direction: column;
}

.sidebar-brand-name {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    letter-spacing: -0.02em;
}

.sidebar-brand-desc {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
}

/* Navigation */
.sidebar-nav {
    flex: 1;
    padding: var(--space-4) var(--space-3);
    overflow-y: auto;
}

.nav-section-title {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: var(--space-4) var(--space-3) var(--space-2);
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-lg);
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-bottom: var(--space-1);
    position: relative;
}

.nav-item:hover {
    color: var(--color-text-primary);
    background: rgba(255, 255, 255, 0.05);
}

.nav-item.active {
    color: var(--color-primary-light);
    background: var(--color-primary-glow);
}

.nav-item.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 60%;
    background: var(--gradient-primary);
    border-radius: var(--radius-full);
}

.nav-item-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    opacity: 0.7;
}

.nav-item.active .nav-item-icon {
    opacity: 1;
}

.nav-item-badge {
    margin-left: auto;
    background: var(--color-primary);
    color: white;
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    padding: 2px 8px;
    border-radius: var(--radius-full);
    min-width: 20px;
    text-align: center;
}

/* Sidebar Footer */
.sidebar-footer {
    padding: var(--space-4) var(--space-3);
    border-top: 1px solid var(--color-border);
}

.sidebar-user {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: background var(--transition-fast);
}

.sidebar-user:hover {
    background: rgba(255, 255, 255, 0.05);
}

.sidebar-user-avatar {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background: var(--gradient-accent);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-bold);
    color: white;
    flex-shrink: 0;
}

.sidebar-user-info {
    flex: 1;
    min-width: 0;
}

.sidebar-user-name {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.sidebar-user-email {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* ========================
   Main Content Area
   ======================== */
.main-content {
    margin-left: var(--sidebar-width);
    flex: 1;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: margin-left var(--transition-base);
}

/* Page Header */
.page-header {
    padding: var(--space-6) var(--space-8);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg-secondary);
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: var(--header-height);
    position: sticky;
    top: 0;
    z-index: var(--z-header);
    backdrop-filter: blur(12px);
}

.page-title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    letter-spacing: -0.02em;
}

.page-subtitle {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-top: var(--space-1);
}

.page-actions {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

/* Page Body */
.page-body {
    padding: var(--space-8);
    flex: 1;
    max-width: var(--content-max-width);
    width: 100%;
    margin: 0 auto;
}

/* ========================
   Cards
   ======================== */
.card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--gradient-glass);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.card:hover {
    border-color: var(--color-border-hover);
    box-shadow: var(--shadow-lg);
}

.card:hover::before {
    opacity: 1;
}

.card-glow {
    box-shadow: var(--shadow-glow);
}

.card-glow:hover {
    box-shadow: var(--shadow-glow-strong);
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-5);
}

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

.card-description {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-top: var(--space-1);
}

/* Stats Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--space-5);
}

.stat-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

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

.stat-card-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-xl);
}

.stat-card-icon.primary { background: var(--color-primary-glow); color: var(--color-primary-light); }
.stat-card-icon.success { background: var(--color-success-bg); color: var(--color-success); }
.stat-card-icon.warning { background: var(--color-warning-bg); color: var(--color-warning); }
.stat-card-icon.info { background: var(--color-info-bg); color: var(--color-info); }
.stat-card-icon.accent { background: rgba(6, 182, 212, 0.1); color: var(--color-accent); }

.stat-card-value {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-extrabold);
    color: var(--color-text-primary);
    letter-spacing: -0.03em;
}

.stat-card-label {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    font-weight: var(--font-weight-medium);
}

.stat-card-trend {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.stat-card-trend.up { color: var(--color-success); }
.stat-card-trend.down { color: var(--color-error); }

/* ========================
   Buttons
   ======================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    font-family: var(--font-family);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    padding: var(--space-3) var(--space-5);
    border-radius: var(--radius-lg);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    line-height: 1;
}

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

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 2px 10px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
    transform: translateY(-1px);
}

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

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

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--color-text-primary);
}

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

.btn-danger:hover {
    background: #dc2626;
    box-shadow: 0 4px 15px rgba(239, 68, 68, 0.3);
}

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

.btn-sm { padding: var(--space-2) var(--space-3); font-size: var(--font-size-xs); }
.btn-lg { padding: var(--space-4) var(--space-8); font-size: var(--font-size-base); }

.btn-icon {
    padding: var(--space-2);
    border-radius: var(--radius-md);
    width: 36px;
    height: 36px;
}

/* ========================
   Form Elements
   ======================== */
.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
    margin-bottom: var(--space-5);
}

.form-label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
}

.form-label .required {
    color: var(--color-error);
    margin-left: var(--space-1);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    background: var(--color-bg-input);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    color: var(--color-text-primary);
    font-family: var(--font-family);
    font-size: var(--font-size-sm);
    transition: all var(--transition-fast);
    outline: none;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-glow);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--color-text-muted);
}

.form-textarea {
    min-height: 120px;
    resize: vertical;
}

.form-error {
    font-size: var(--font-size-xs);
    color: var(--color-error);
}

.form-hint {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
}

/* ========================
   Tables
   ======================== */
.table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border);
}

.data-table {
    width: 100%;
    border-collapse: collapse;
}

.data-table thead {
    background: var(--color-bg-tertiary);
}

.data-table th {
    padding: var(--space-3) var(--space-4);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}

.data-table td {
    padding: var(--space-4);
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    border-bottom: 1px solid var(--color-border);
    transition: background var(--transition-fast);
}

.data-table tbody tr:hover td {
    background: rgba(255, 255, 255, 0.02);
}

.data-table tbody tr:last-child td {
    border-bottom: none;
}

/* ========================
   Badges & Tags
   ======================== */
.badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    border-radius: var(--radius-full);
}

.badge-primary { background: var(--color-primary-glow); color: var(--color-primary-light); }
.badge-success { background: var(--color-success-bg); color: var(--color-success); }
.badge-warning { background: var(--color-warning-bg); color: var(--color-warning); }
.badge-error { background: var(--color-error-bg); color: var(--color-error); }
.badge-info { background: var(--color-info-bg); color: var(--color-info); }

/* ========================
   Upload Zone
   ======================== */
.upload-zone {
    border: 2px dashed var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-12) var(--space-8);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-base);
    background: var(--color-bg-card);
    position: relative;
}

.upload-zone:hover,
.upload-zone.drag-over {
    border-color: var(--color-primary);
    background: var(--color-primary-glow);
    box-shadow: var(--shadow-glow);
}

.upload-zone-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto var(--space-4);
    color: var(--color-primary-light);
    opacity: 0.7;
}

.upload-zone-text {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
    margin-bottom: var(--space-2);
}

.upload-zone-hint {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

/* ========================
   Auth Page (Login/Register)
   ======================== */
.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-primary);
    position: relative;
    overflow: hidden;
}

/* Animated background */
.auth-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
    z-index: 0;
}

.auth-bg-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.3;
    animation: float 15s ease-in-out infinite;
}

.auth-bg-orb:nth-child(1) {
    width: 400px;
    height: 400px;
    background: var(--color-primary);
    top: -100px;
    right: -100px;
    animation-delay: 0s;
}

.auth-bg-orb:nth-child(2) {
    width: 300px;
    height: 300px;
    background: var(--color-secondary);
    bottom: -80px;
    left: -80px;
    animation-delay: -5s;
}

.auth-bg-orb:nth-child(3) {
    width: 200px;
    height: 200px;
    background: var(--color-accent);
    top: 50%;
    left: 50%;
    animation-delay: -10s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -30px) scale(1.1); }
    66% { transform: translate(-20px, 20px) scale(0.9); }
}

.auth-container {
    position: relative;
    z-index: 1;
    width: 100%;
    max-width: 440px;
    padding: var(--space-6);
}

.auth-card {
    background: rgba(17, 24, 39, 0.8);
    backdrop-filter: blur(20px);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    padding: var(--space-10);
    box-shadow: var(--shadow-xl);
}

.auth-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    margin-bottom: var(--space-8);
}

.auth-logo-icon {
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    box-shadow: var(--shadow-glow);
}

.auth-logo-text {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    letter-spacing: -0.02em;
}

.auth-title {
    text-align: center;
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    margin-bottom: var(--space-2);
}

.auth-subtitle {
    text-align: center;
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-8);
}

.auth-divider {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    margin: var(--space-6) 0;
    color: var(--color-text-tertiary);
    font-size: var(--font-size-xs);
}

.auth-divider::before,
.auth-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--color-border);
}

.auth-footer {
    text-align: center;
    margin-top: var(--space-6);
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.auth-footer a {
    color: var(--color-primary-light);
    font-weight: var(--font-weight-medium);
}

.btn-google {
    width: 100%;
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    color: var(--color-text-primary);
    padding: var(--space-3) var(--space-5);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    font-family: var(--font-family);
}

.btn-google:hover {
    background: var(--color-bg-card-hover);
    border-color: var(--color-border-hover);
}

/* ========================
   Prompt Editor
   ======================== */
.prompt-editor {
    background: var(--color-bg-input);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    overflow: hidden;
}

.prompt-editor-toolbar {
    padding: var(--space-3) var(--space-4);
    background: var(--color-bg-tertiary);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.prompt-editor-content {
    padding: var(--space-4);
    min-height: 300px;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-primary);
    border: none;
    background: transparent;
    width: 100%;
    resize: vertical;
    outline: none;
}

/* ========================
   Toasts / Notifications
   ======================== */
.toast-container {
    position: fixed;
    top: var(--space-6);
    right: var(--space-6);
    z-index: var(--z-toast);
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.toast {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-4) var(--space-5);
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-width: 320px;
    max-width: 480px;
    box-shadow: var(--shadow-xl);
    animation: slideInRight 0.3s ease-out;
}

.toast.success { border-left: 3px solid var(--color-success); }
.toast.error { border-left: 3px solid var(--color-error); }
.toast.warning { border-left: 3px solid var(--color-warning); }
.toast.info { border-left: 3px solid var(--color-info); }

@keyframes slideInRight {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

/* ========================
   Loading Spinner
   ======================== */
.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

.spinner-lg { width: 40px; height: 40px; border-width: 3px; }

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

/* ========================
   Empty State
   ======================== */
.empty-state {
    text-align: center;
    padding: var(--space-16) var(--space-8);
    color: var(--color-text-tertiary);
}

.empty-state-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--space-4);
    opacity: 0.4;
}

.empty-state-title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-2);
}

.empty-state-text {
    font-size: var(--font-size-sm);
    max-width: 400px;
    margin: 0 auto;
}

/* ========================
   Modal
   ======================== */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: var(--color-bg-overlay);
    backdrop-filter: blur(4px);
    z-index: var(--z-modal);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    width: 90%;
    max-width: 560px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.95) translateY(10px);
    transition: transform var(--transition-spring);
    box-shadow: var(--shadow-xl);
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    padding: var(--space-6);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-body { padding: var(--space-6); }
.modal-footer {
    padding: var(--space-4) var(--space-6);
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: flex-end;
    gap: var(--space-3);
}

/* ========================
   Page Transitions
   ======================== */
.page-view {
    display: none;
    animation: fadeIn 0.3s ease-out;
}

.page-view.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ========================
   Grid Layouts
   ======================== */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-5); }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-5); }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-5); }

/* ========================
   Utility Classes
   ======================== */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-5 { gap: var(--space-5); }
.gap-6 { gap: var(--space-6); }

.text-center { text-align: center; }
.text-right { text-align: right; }
.text-sm { font-size: var(--font-size-sm); }
.text-xs { font-size: var(--font-size-xs); }
.text-muted { color: var(--color-text-tertiary); }
.text-primary { color: var(--color-primary-light); }
.text-success { color: var(--color-success); }
.text-error { color: var(--color-error); }

.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

.w-full { width: 100%; }
.hidden { display: none !important; }

/* ========================
   Responsive
   ======================== */
@media (max-width: 1024px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }

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

    .main-content {
        margin-left: 0;
    }

    .page-header {
        padding: var(--space-4) var(--space-5);
    }

    .page-body {
        padding: var(--space-5);
    }

    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .auth-card {
        padding: var(--space-6);
    }
}

@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }
}