/**
 * AI TUTOR PAKISTAN - UNIVERSAL THEME
 * Professional Blue Design - Applies to ALL Pages
 * Based on Quick Creators Design
 * Version: 1.0
 */

/* ============================================
   CSS VARIABLES - Easy Customization
   ============================================ */
:root {
    /* Primary Brand Colors */
    --primary-blue: #00A8E8;
    --primary-blue-dark: #0088BB;
    --primary-blue-light: #33BFEF;
    --primary-blue-lighter: #E6F7FF;
    
    /* Dark Colors */
    --navy-dark: #1A2332;
    --navy-medium: #2C3E50;
    --navy-light: #34495E;
    
    /* Gray Scale */
    --white: #FFFFFF;
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-400: #9CA3AF;
    --gray-500: #6B7280;
    --gray-600: #4B5563;
    --gray-700: #374151;
    --gray-800: #1F2937;
    --gray-900: #111827;
    
    /* Status Colors */
    --success: #10B981;
    --success-light: #D1FAE5;
    --success-dark: #065F46;
    --warning: #F59E0B;
    --warning-light: #FEF3C7;
    --warning-dark: #92400E;
    --error: #EF4444;
    --error-light: #FEE2E2;
    --error-dark: #991B1B;
    --info: var(--primary-blue);
    --info-light: #DBEAFE;
    --info-dark: #1E40AF;
    
    /* Spacing System */
    --spacing-xs: 0.25rem;      /* 4px */
    --spacing-sm: 0.5rem;       /* 8px */
    --spacing-md: 1rem;         /* 16px */
    --spacing-lg: 1.5rem;       /* 24px */
    --spacing-xl: 2rem;         /* 32px */
    --spacing-2xl: 3rem;        /* 48px */
    --spacing-3xl: 4rem;        /* 64px */
    
    /* Border Radius */
    --radius-sm: 0.375rem;      /* 6px */
    --radius-md: 0.5rem;        /* 8px */
    --radius-lg: 0.75rem;       /* 12px */
    --radius-xl: 1rem;          /* 16px */
    --radius-2xl: 1.5rem;       /* 24px */
    --radius-full: 9999px;      /* Full round */
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 200ms ease-in-out;
    --transition-slow: 300ms ease-in-out;
    
    /* Container Max Width */
    --container-max: 1400px;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Helvetica Neue', Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-800);
    background-color: var(--gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

/* ============================================
   TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--navy-dark);
    margin-bottom: var(--spacing-md);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1.125rem; }

p {
    margin-bottom: var(--spacing-md);
    color: var(--gray-600);
}

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

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

strong {
    font-weight: 700;
}

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

.container-fluid {
    width: 100%;
    padding: 0 var(--spacing-xl);
}

.section {
    padding: var(--spacing-3xl) 0;
}

/* ============================================
   HEADER & NAVIGATION
   ============================================ */
.header {
    background: var(--white);
    box-shadow: var(--shadow-sm);
    padding: var(--spacing-md) 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 2px solid var(--primary-blue);
}

.header-content {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-blue);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    text-decoration: none;
}

.nav-menu {
    display: flex;
    gap: var(--spacing-xl);
    align-items: center;
    list-style: none;
}

.nav-link {
    color: var(--gray-700);
    font-weight: 500;
    padding: var(--spacing-sm) var(--spacing-md);
    transition: all var(--transition-base);
    text-decoration: none;
}

.nav-link:hover {
    color: var(--primary-blue);
}

.nav-link.active {
    color: var(--primary-blue);
    font-weight: 600;
}

/* ============================================
   BUTTONS - Universal Button Styles
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    line-height: 1;
    border: none;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    white-space: nowrap;
}

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

/* Button Variants */
.btn-primary {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-dark));
    color: var(--white);
}

.btn-primary:hover:not(:disabled) {
    background: var(--primary-blue-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--gray-100);
    color: var(--gray-700);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--gray-200);
}

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

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

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

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

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

.btn-outline {
    background: transparent;
    color: var(--primary-blue);
    border: 2px solid var(--primary-blue);
}

.btn-outline:hover:not(:disabled) {
    background: var(--primary-blue);
    color: var(--white);
}

/* Button Sizes */
.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-xl {
    padding: 1.25rem 2.5rem;
    font-size: 1.25rem;
}

/* ============================================
   CARDS - Universal Card Component
   ============================================ */
.card {
    background: var(--white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xl);
    transition: all var(--transition-base);
}

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

.card-header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px solid var(--gray-100);
}

.card-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--navy-dark);
    margin-bottom: var(--spacing-sm);
}

.card-subtitle {
    font-size: 1rem;
    color: var(--gray-500);
    margin: 0;
}

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

.card-footer {
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--gray-100);
}

/* ============================================
   FORMS - Universal Form Styles
   ============================================ */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--gray-700);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-family: inherit;
    transition: all var(--transition-base);
    background: var(--white);
    color: var(--gray-800);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px var(--primary-blue-lighter);
}

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

.form-help {
    display: block;
    margin-top: var(--spacing-xs);
    font-size: 0.875rem;
    color: var(--gray-500);
}

.form-error {
    display: block;
    margin-top: var(--spacing-xs);
    font-size: 0.875rem;
    color: var(--error);
}

/* ============================================
   ALERTS & MESSAGES
   ============================================ */
.alert {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    font-weight: 500;
}

.alert-success {
    background: var(--success-light);
    color: var(--success-dark);
    border-left: 4px solid var(--success);
}

.alert-error {
    background: var(--error-light);
    color: var(--error-dark);
    border-left: 4px solid var(--error);
}

.alert-warning {
    background: var(--warning-light);
    color: var(--warning-dark);
    border-left: 4px solid var(--warning);
}

.alert-info {
    background: var(--info-light);
    color: var(--info-dark);
    border-left: 4px solid var(--info);
}

/* ============================================
   BADGES
   ============================================ */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 600;
    line-height: 1;
}

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

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

.badge-warning {
    background: var(--warning);
    color: var(--white);
}

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

.badge-gray {
    background: var(--gray-200);
    color: var(--gray-700);
}

/* ============================================
   TABLES - Universal Table Styles
   ============================================ */
.table-container {
    background: var(--white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

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

thead {
    background: var(--gray-50);
}

thead th {
    padding: var(--spacing-md) var(--spacing-lg);
    text-align: left;
    font-weight: 600;
    color: var(--gray-700);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

tbody tr {
    border-bottom: 1px solid var(--gray-100);
    transition: background var(--transition-fast);
}

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

tbody tr:hover {
    background: var(--gray-50);
}

tbody td {
    padding: var(--spacing-md) var(--spacing-lg);
    color: var(--gray-600);
}

/* ============================================
   FOOTER - Universal Footer
   ============================================ */
.footer {
    background: var(--navy-dark);
    color: var(--white);
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
    margin-top: var(--spacing-3xl);
}

.footer-content {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-2xl);
}

.footer-section h3 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
    font-size: 1.125rem;
}

.footer-section p,
.footer-section a {
    color: var(--gray-300);
    margin-bottom: var(--spacing-sm);
    display: block;
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-xl);
    margin-top: var(--spacing-xl);
    border-top: 1px solid var(--gray-700);
    color: var(--gray-400);
}

/* ============================================
   STATS CARDS
   ============================================ */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.stat-card {
    background: var(--white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    transition: all var(--transition-base);
}

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

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    flex-shrink: 0;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-dark));
    color: var(--white);
}

.stat-content h3 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--navy-dark);
    margin: 0 0 0.25rem 0;
}

.stat-content p {
    font-size: 0.875rem;
    color: var(--gray-500);
    margin: 0;
}

/* ============================================
   MODALS
   ============================================ */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 9999;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--white);
    padding: var(--spacing-2xl);
    border-radius: var(--radius-xl);
    max-width: 500px;
    width: 90%;
    box-shadow: var(--shadow-2xl);
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.modal-header h2 {
    margin: 0;
    color: var(--navy-dark);
}

.close-modal {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray-400);
    transition: color var(--transition-base);
}

.close-modal:hover {
    color: var(--gray-600);
}

/* ============================================
   TABS
   ============================================ */
.tab-nav {
    background: var(--white);
    border-radius: var(--radius-xl);
    padding: 0.5rem;
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    gap: 0.5rem;
    overflow-x: auto;
}

.tab-btn {
    flex: 1;
    padding: 0.875rem 1.5rem;
    border: none;
    background: transparent;
    color: var(--gray-600);
    font-weight: 600;
    font-size: 1rem;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    white-space: nowrap;
}

.tab-btn:hover {
    background: var(--gray-50);
    color: var(--primary-blue);
}

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

.tab-content {
    display: none;
}

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

/* ============================================
   UTILITY CLASSES
   ============================================ */

/* Text Alignment */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

/* Margin */
.mt-1 { margin-top: var(--spacing-md); }
.mt-2 { margin-top: var(--spacing-lg); }
.mt-3 { margin-top: var(--spacing-xl); }
.mb-1 { margin-bottom: var(--spacing-md); }
.mb-2 { margin-bottom: var(--spacing-lg); }
.mb-3 { margin-bottom: var(--spacing-xl); }
.my-1 { margin-top: var(--spacing-md); margin-bottom: var(--spacing-md); }
.my-2 { margin-top: var(--spacing-lg); margin-bottom: var(--spacing-lg); }
.my-3 { margin-top: var(--spacing-xl); margin-bottom: var(--spacing-xl); }

/* Padding */
.p-1 { padding: var(--spacing-md); }
.p-2 { padding: var(--spacing-lg); }
.p-3 { padding: var(--spacing-xl); }
.py-1 { padding-top: var(--spacing-md); padding-bottom: var(--spacing-md); }
.py-2 { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }
.py-3 { padding-top: var(--spacing-xl); padding-bottom: var(--spacing-xl); }

/* Flexbox */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-around { justify-content: space-around; }
.gap-1 { gap: var(--spacing-md); }
.gap-2 { gap: var(--spacing-lg); }
.gap-3 { gap: var(--spacing-xl); }

/* Grid */
.grid { display: grid; }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

/* Border Radius */
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }

/* Shadow */
.shadow { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }

/* Display */
.hidden { display: none; }
.block { display: block; }
.inline-block { display: inline-block; }

/* Width */
.w-full { width: 100%; }
.w-auto { width: auto; }

/* ============================================
   ANIMATIONS
   ============================================ */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.fade-in {
    animation: fadeIn var(--transition-slow);
}

.slide-up {
    animation: slideUp var(--transition-slow);
}

.slide-down {
    animation: slideDown var(--transition-slow);
}

.scale-in {
    animation: scaleIn var(--transition-slow);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 1024px) {
    .container {
        padding: 0 var(--spacing-lg);
    }
    
    .stats-grid {
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    }
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
    
    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    h3 { font-size: 1.5rem; }
    
    .header-content {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .nav-menu {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .tab-nav {
        overflow-x: auto;
    }
    
    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .btn {
        width: 100%;
    }
    
    .modal-content {
        width: 95%;
        padding: var(--spacing-lg);
    }
}

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
    .header,
    .footer,
    .btn,
    .nav-menu {
        display: none;
    }
    
    body {
        background: white;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid var(--gray-300);
    }
}

/* ============================================
   ACCESSIBILITY
   ============================================ */
*:focus-visible {
    outline: 2px solid var(--primary-blue);
    outline-offset: 2px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* ============================================
   DARK MODE SUPPORT (Optional)
   ============================================ */
@media (prefers-color-scheme: dark) {
    /* Uncomment and customize for dark mode */
    /* 
    :root {
        --gray-50: #1F2937;
        --gray-900: #F9FAFB;
    }
    */
}