/*
Theme Name: LMS Academy Custom
Theme URI: https://your-lms-site.com
Author: LMS Academy
Description: A complete custom LMS theme with membership, courses, subjects, and protected video lessons.
Version: 3.0.0
*/

/* ==========================================================================
   CSS VARIABLES - Academic Design System with Light/Dark Themes
   ========================================================================== */

:root {
    /* Light Theme (Default) */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --bg-hover: #e2e8f0;
    
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-muted: #64748b;
    --text-light: #94a3b8;
    
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;
    
    /* Brand Colors */
    --color-brand: #0f4c81;
    --color-brand-light: #1e6bb8;
    --color-brand-dark: #0a3459;
    
    /* Accent Colors */
    --color-accent: #dc2626;
    --color-accent-light: #ef4444;
    
    /* Status Colors */
    --color-success: #059669;
    --color-warning: #d97706;
    --color-info: #0284c7;
    
    /* Category Colors */
    --color-science: #7c3aed;
    --color-math: #2563eb;
    --color-language: #059669;
    --color-business: #ea580c;
    --color-humanities: #db2777;
    --color-creative: #8b5cf6;
    
    /* Typography */
    --font-heading: 'Merriweather', Georgia, serif;
    --font-body: 'Source Sans Pro', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'Fira Code', monospace;
    
    /* Sizes */
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 2rem;
    --text-4xl: 2.5rem;
    --text-5xl: 3.5rem;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.5rem;
    --space-6: 2rem;
    --space-8: 3rem;
    --space-10: 4rem;
    --space-12: 5rem;
    --space-16: 8rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 24px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px rgba(0,0,0,0.1);
    
    /* Navbar */
    --navbar-bg: rgba(255,255,255,0.95);
    --navbar-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

/* Dark Theme */
[data-theme="dark"] {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --bg-card: #1e293b;
    --bg-hover: #334155;
    
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --text-light: #64748b;
    
    --border-color: #334155;
    --border-light: #1e293b;
    
    --color-brand: #3b82f6;
    --color-brand-light: #60a5fa;
    --color-brand-dark: #2563eb;
    
    --navbar-bg: rgba(15,23,42,0.95);
    --navbar-shadow: 0 1px 3px rgba(0,0,0,0.3);
    
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.3);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.4);
}

/* ==========================================================================
   BASE STYLES
   ========================================================================== */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: var(--text-base);
    line-height: 1.7;
    color: var(--text-primary);
    background: var(--bg-primary);
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-primary);
    margin-bottom: var(--space-4);
}

h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }

p {
    margin-bottom: var(--space-4);
    color: var(--text-secondary);
}

a {
    color: var(--color-brand);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--color-brand-light);
}

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

/* ==========================================================================
   LAYOUT
   ========================================================================== */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-5);
}

.container-sm { max-width: 680px; }
.container-lg { max-width: 1400px; }

.section {
    padding: var(--space-16) 0;
}

.section-sm {
    padding: var(--space-10) 0;
}

/* ==========================================================================
   NAVIGATION
   ========================================================================== */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: var(--space-4) var(--space-6);
    background: var(--navbar-bg);
    backdrop-filter: blur(12px);
    box-shadow: var(--navbar-shadow);
    transition: all 0.3s ease;
}

.navbar-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-family: var(--font-heading);
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--color-brand);
}

.navbar-brand img {
    height: 40px;
}

.navbar-nav {
    display: flex;
    gap: var(--space-6);
    list-style: none;
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: var(--space-2) 0;
    position: relative;
    transition: color 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-brand);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-brand);
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.navbar-actions {
    display: flex;
    gap: var(--space-3);
    align-items: center;
    position: relative;
    z-index: 9999;
}

/* Cart Icon */
.cart-icon {
    position: relative;
    font-size: 1.3rem;
    padding: 8px;
    text-decoration: none;
    transition: transform 0.2s;
}

.cart-icon:hover {
    transform: scale(1.1);
}

.cart-badge {
    position: absolute;
    top: 0;
    right: 0;
    background: var(--color-accent);
    color: #fff;
    font-size: 0.65rem;
    font-weight: 700;
    min-width: 18px;
    height: 18px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
}

/* Theme Toggle */
.theme-toggle {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    padding: 10px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    width: 44px;
    height: 44px;
    min-width: 44px;
    min-height: 44px;
    position: relative;
    z-index: 100;
}

.theme-toggle:hover {
    background: var(--bg-hover);
    transform: scale(1.05);
}

.theme-toggle:active {
    transform: scale(0.95);
}

.theme-toggle svg {
    width: 22px;
    height: 22px;
    color: var(--text-secondary);
    pointer-events: none;
}

.theme-toggle .sun-icon { display: none; }
.theme-toggle .moon-icon { display: block; }

[data-theme="dark"] .theme-toggle .sun-icon { display: block; }
[data-theme="dark"] .theme-toggle .moon-icon { display: none; }

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 48px;
    height: 48px;
    background: var(--color-brand);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    padding: 12px;
    position: relative;
    z-index: 10000;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}

.mobile-menu-btn .hamburger-line {
    display: block;
    width: 24px;
    height: 3px;
    background: #ffffff;
    margin: 3px 0;
    border-radius: 3px;
    transition: all 0.3s ease;
}

.mobile-menu-btn.open {
    background: var(--color-accent);
}

.mobile-menu-btn.open .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.mobile-menu-btn.open .hamburger-line:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.open .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* Body when menu is open */
body.menu-open {
    overflow: hidden;
}

/* ==========================================================================
   BUTTONS
   ========================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-family: var(--font-body);
    font-size: var(--text-base);
    font-weight: 600;
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
}

.btn-primary {
    background: var(--color-brand);
    color: #ffffff;
    border-color: var(--color-brand);
}

.btn-primary:hover {
    background: var(--color-brand-dark);
    border-color: var(--color-brand-dark);
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-secondary:hover {
    background: var(--color-brand);
    color: #ffffff;
}

.btn-accent {
    background: var(--color-accent);
    color: #ffffff;
    border-color: var(--color-accent);
}

.btn-accent:hover {
    background: var(--color-accent-light);
    border-color: var(--color-accent-light);
    color: #ffffff;
}

.btn-white {
    background: #ffffff;
    color: var(--color-brand);
    border-color: #ffffff;
}

.btn-white:hover {
    background: var(--bg-secondary);
    color: var(--color-brand);
}

.btn-lg {
    padding: var(--space-4) var(--space-8);
    font-size: var(--text-lg);
}

.btn-sm {
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
}

.btn-block {
    width: 100%;
}

/* ==========================================================================
   CARDS
   ========================================================================== */

.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    overflow: hidden;
    transition: all 0.3s ease;
}

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

.card-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

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

.card-title {
    font-size: var(--text-xl);
    margin-bottom: var(--space-3);
    color: var(--text-primary);
}

.card-text {
    color: var(--text-muted);
    margin-bottom: var(--space-4);
}

/* Icon Cards */
.icon-card {
    text-align: center;
    padding: var(--space-8);
}

.icon-card .icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-5);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
}

.icon-card .icon svg {
    width: 40px;
    height: 40px;
}

/* ==========================================================================
   HERO SECTION
   ========================================================================== */

.hero {
    min-height: 90vh;
    display: flex;
    align-items: center;
    padding: var(--space-16) 0;
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 50%;
    height: 100%;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%230f4c81' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    opacity: 0.5;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    background: var(--color-brand);
    color: #ffffff;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-weight: 600;
    margin-bottom: var(--space-5);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: var(--space-5);
    line-height: 1.1;
}

.hero-title span {
    color: var(--color-brand);
}

.hero-subtitle {
    font-size: var(--text-xl);
    color: var(--text-secondary);
    margin-bottom: var(--space-8);
    max-width: 600px;
}

.hero-actions {
    display: flex;
    gap: var(--space-4);
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    gap: var(--space-10);
    margin-top: var(--space-10);
    padding-top: var(--space-8);
    border-top: 1px solid var(--border-color);
}

.hero-stat {
    text-align: center;
}

.hero-stat-value {
    font-size: var(--text-3xl);
    font-weight: 700;
    color: var(--color-brand);
    font-family: var(--font-heading);
}

.hero-stat-label {
    color: var(--text-muted);
    font-size: var(--text-sm);
}

/* ==========================================================================
   FORMS
   ========================================================================== */

.form-group {
    margin-bottom: var(--space-5);
}

.form-label {
    display: block;
    margin-bottom: var(--space-2);
    font-weight: 600;
    color: var(--text-primary);
}

.form-control {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    font-size: var(--text-base);
    color: var(--text-primary);
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--color-brand);
    box-shadow: 0 0 0 3px rgba(15, 76, 129, 0.1);
}

.form-control::placeholder {
    color: var(--text-light);
}

/* ==========================================================================
   TABLES
   ========================================================================== */

.table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

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

.table th,
.table td {
    padding: var(--space-4);
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.table th {
    font-weight: 600;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: var(--text-sm);
}

.table tbody tr:hover {
    background: var(--bg-tertiary);
}

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

/* ==========================================================================
   BADGES & TAGS
   ========================================================================== */

.badge {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    font-size: var(--text-xs);
    font-weight: 600;
    border-radius: var(--radius-full);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-science { background: rgba(124, 58, 237, 0.1); color: var(--color-science); }
.badge-math { background: rgba(37, 99, 235, 0.1); color: var(--color-math); }
.badge-language { background: rgba(5, 150, 105, 0.1); color: var(--color-language); }
.badge-business { background: rgba(234, 88, 12, 0.1); color: var(--color-business); }
.badge-humanities { background: rgba(219, 39, 119, 0.1); color: var(--color-humanities); }
.badge-creative { background: rgba(139, 92, 246, 0.1); color: var(--color-creative); }

/* ==========================================================================
   TEAM CARDS
   ========================================================================== */

.team-card {
    text-align: center;
}

.team-card .avatar {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    margin: 0 auto var(--space-5);
    border: 4px solid var(--bg-tertiary);
}

.team-card .name {
    font-size: var(--text-xl);
    margin-bottom: var(--space-1);
}

.team-card .role {
    color: var(--color-brand);
    font-weight: 600;
    margin-bottom: var(--space-3);
}

.team-card .bio {
    color: var(--text-muted);
    font-size: var(--text-sm);
    margin-bottom: var(--space-4);
}

/* ==========================================================================
   ACCORDION
   ========================================================================== */

.accordion {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--bg-card);
}

.accordion-item {
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-card);
}

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

.accordion-header {
    padding: var(--space-5);
    background: var(--bg-card);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    user-select: none;
    align-items: center;
    font-weight: 600;
    transition: background 0.3s ease;
}

.accordion-header:hover {
    background: var(--bg-tertiary);
}

.accordion-header svg {
    transition: transform 0.3s ease;
}

.accordion-item.active .accordion-header svg {
    transform: rotate(180deg);
}

.accordion-body {
    padding: 0 var(--space-5);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    background: var(--bg-card);
    display: none;
}

.accordion-item.active .accordion-body {
    padding: var(--space-5);
    max-height: 2000px;
    display: block;
}

.accordion-body h4 {
    margin-bottom: var(--space-3);
    color: var(--text-primary);
}

.accordion-body ul {
    color: var(--text-secondary);
}

/* ==========================================================================
   TABS
   ========================================================================== */

.tabs {
    display: flex;
    gap: var(--space-2);
    border-bottom: 2px solid var(--border-color);
    margin-bottom: var(--space-6);
    overflow-x: auto;
}

.tab {
    padding: var(--space-3) var(--space-5);
    font-weight: 600;
    color: var(--text-muted);
    background: none;
    border: none;
    cursor: pointer;
    position: relative;
    white-space: nowrap;
    transition: color 0.3s ease;
}

.tab:hover,
.tab.active {
    color: var(--color-brand);
}

.tab.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--color-brand);
}

.tab-content {
    display: none;
}

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

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

/* ==========================================================================
   FOOTER
   ========================================================================== */

.footer {
    background: var(--bg-secondary);
    padding: var(--space-12) 0 var(--space-6);
    border-top: 1px solid var(--border-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: var(--space-10);
    margin-bottom: var(--space-10);
}

.footer-brand {
    font-family: var(--font-heading);
    font-size: var(--text-2xl);
    color: var(--color-brand);
    margin-bottom: var(--space-4);
}

.footer-desc {
    color: var(--text-muted);
    margin-bottom: var(--space-5);
}

.footer-title {
    font-size: var(--text-lg);
    margin-bottom: var(--space-4);
    color: var(--text-primary);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--space-2);
}

.footer-links a {
    color: var(--text-muted);
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: var(--color-brand);
}

.footer-bottom {
    padding-top: var(--space-6);
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-muted);
    font-size: var(--text-sm);
}

/* ==========================================================================
   DASHBOARD SIDEBAR
   ========================================================================== */

.dashboard {
    display: flex;
    min-height: 100vh;
    padding-top: 80px;
}

.dashboard-sidebar {
    width: 280px;
    background: var(--bg-secondary);
    padding: var(--space-6);
    position: fixed;
    top: 80px;
    bottom: 0;
    left: 0;
    overflow-y: auto;
    border-right: 1px solid var(--border-color);
}

.dashboard-content {
    flex: 1;
    margin-left: 280px;
    padding: var(--space-6);
}

.sidebar-nav {
    list-style: none;
}

.sidebar-nav-item {
    margin-bottom: var(--space-2);
}

.sidebar-nav-link {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
}

.sidebar-nav-link:hover,
.sidebar-nav-link.active {
    background: var(--color-brand);
    color: #ffffff;
}

/* ==========================================================================
   AUTH PAGES
   ========================================================================== */

.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-6);
    background: var(--bg-secondary);
}

.auth-card {
    width: 100%;
    max-width: 450px;
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    box-shadow: var(--shadow-xl);
}

.auth-header {
    text-align: center;
    margin-bottom: var(--space-8);
}

.auth-title {
    font-size: var(--text-3xl);
    margin-bottom: var(--space-2);
}

.auth-subtitle {
    color: var(--text-muted);
}

/* ==========================================================================
   ALERTS
   ========================================================================== */

.alert {
    padding: var(--space-4);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-5);
    border: 1px solid;
}

.alert-success {
    background: rgba(5, 150, 105, 0.1);
    border-color: var(--color-success);
    color: var(--color-success);
}

.alert-danger {
    background: rgba(220, 38, 38, 0.1);
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.alert-warning {
    background: rgba(217, 119, 6, 0.1);
    border-color: var(--color-warning);
    color: var(--color-warning);
}

.alert-info {
    background: rgba(2, 132, 199, 0.1);
    border-color: var(--color-info);
    color: var(--color-info);
}

/* ==========================================================================
   VIDEO PLAYER
   ========================================================================== */

.video-container {
    position: relative;
    width: 100%;
    background: #000;
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.video-container::before {
    content: '';
    display: block;
    padding-top: 56.25%;
}

.video-container video,
.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.video-protected {
    -webkit-user-select: none;
    user-select: none;
}

/* ==========================================================================
   GRID LAYOUTS
   ========================================================================== */

.grid {
    display: grid;
    gap: var(--space-6);
}

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

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--space-6);
}

/* ==========================================================================
   UTILITIES
   ========================================================================== */

.text-center { text-align: center; }
.text-right { text-align: right; }
.text-brand { color: var(--color-brand); }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--color-success); }
.text-danger { color: var(--color-accent); }

.bg-brand { background: var(--color-brand); }
.bg-secondary { background: var(--bg-secondary); }
.bg-tertiary { background: var(--bg-tertiary); }

.mb-0 { margin-bottom: 0; }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-10 { margin-bottom: var(--space-10); }

.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-10 { margin-top: var(--space-10); }

.pt-8 { padding-top: var(--space-8); }
.pb-8 { padding-bottom: var(--space-8); }

.d-flex { display: flex; }
.flex-wrap { flex-wrap: wrap; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.align-center { align-items: center; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */

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

@media (max-width: 768px) {
    .navbar-container {
        padding: 0 15px;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .navbar-nav {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: #0f4c81;
        display: none;
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        gap: 15px;
        z-index: 9000;
        padding: 100px 30px 30px 30px;
        list-style: none;
    }
    
    .navbar-nav.open {
        display: flex;
        height: 100vh;
    }
    
    .navbar-nav li {
        width: 100%;
        text-align: center;
    }
    
    .navbar-nav .nav-link {
        color: #ffffff;
        font-size: 1.3rem;
        font-weight: 600;
        padding: 15px 25px;
        display: block;
        border-radius: 10px;
        border: none;
        text-decoration: none;
    }
    
    .navbar-nav .nav-link:hover,
    .navbar-nav .nav-link:focus {
        background: rgba(255,255,255,0.2);
        color: #ffffff;
    }
    
    .navbar-actions {
        gap: 10px;
    }
    
    .navbar-actions .btn {
        display: none;
    }
    
    .navbar-actions .theme-toggle,
    .navbar-actions .cart-icon {
        display: flex;
    }
    
    .hero {
        min-height: auto;
        padding: var(--space-12) 0;
    }
    
    .hero-title {
        font-size: var(--text-3xl);
    }
    
    .hero-stats {
        flex-direction: column;
        gap: var(--space-5);
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .hero-actions .btn {
        width: 100%;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .grid-2,
    .grid-3,
    .grid-4 { grid-template-columns: 1fr; }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .dashboard-sidebar {
        display: none;
    }
    
    .dashboard-content {
        margin-left: 0;
    }
    
    .tabs {
        flex-wrap: nowrap;
        -webkit-overflow-scrolling: touch;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--space-4);
    }
    
    .section {
        padding: var(--space-10) 0;
    }
    
    h1 { font-size: var(--text-2xl); }
    h2 { font-size: var(--text-xl); }
}