/* ==========================================
   COURSE PLATFORM - MAIN STYLES
   Modern, RTL-friendly Arabic Design
   ========================================== */

/* CSS Variables */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #10b981;
    --accent: #f59e0b;
    --dark: #1e1e2e;
    --dark-light: #2a2a3e;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    --gradient-accent: linear-gradient(135deg, var(--accent) 0%, #ea580c 100%);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 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);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Cairo', sans-serif;
    background: var(--gray-100);
    color: var(--dark);
    line-height: 1.6;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==========================================
   BUTTONS
   ========================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    border: none;
    transition: var(--transition);
}

.btn-primary {
    background: var(--gradient);
    color: var(--white);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

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

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

.btn-glass {
    background: rgba(255,255,255,0.15);
    backdrop-filter: blur(10px);
    color: var(--white);
    border: 1px solid rgba(255,255,255,0.2);
}

.btn-glass:hover {
    background: rgba(255,255,255,0.25);
}

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

.btn-white:hover {
    background: var(--gray-100);
    transform: translateY(-2px);
}

.btn-lg {
    padding: 16px 32px;
    font-size: 1.1rem;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 0.9rem;
}

/* ==========================================
   NAVBAR
   ========================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    padding: 15px 0;
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--dark);
}

.logo-icon {
    font-size: 2rem;
}

.nav-links {
    display: flex;
    gap: 30px;
}

.nav-links a {
    color: var(--gray-600);
    font-weight: 500;
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--primary);
    border-radius: 2px;
}

.nav-buttons {
    display: flex;
    gap: 12px;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* ==========================================
   HERO SECTION
   ========================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #1e1e2e 0%, #2d1b4e 50%, #1e1e2e 100%);
    overflow: hidden;
    padding-top: 80px;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(99, 102, 241, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(16, 185, 129, 0.2) 0%, transparent 40%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    color: var(--white);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
}

.hero-title .highlight {
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--gray-300);
    margin-bottom: 30px;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 15px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    gap: 40px;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--accent);
}

.stat-label {
    color: var(--gray-400);
    font-size: 0.9rem;
}

.hero-image {
    position: relative;
    height: 400px;
}

.floating-card {
    position: absolute;
    background: rgba(255,255,255,0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: var(--radius);
    padding: 15px 20px;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--white);
    animation: float 3s ease-in-out infinite;
}

.card-1 { top: 20%; right: 10%; animation-delay: 0s; }
.card-2 { top: 50%; left: 5%; animation-delay: 0.5s; }
.card-3 { bottom: 20%; right: 20%; animation-delay: 1s; }

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

.card-icon {
    font-size: 1.5rem;
}

/* ==========================================
   SECTIONS
   ========================================== */
section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--dark);
    margin-bottom: 15px;
}

.section-subtitle {
    color: var(--gray-500);
    font-size: 1.1rem;
}

.section-footer {
    text-align: center;
    margin-top: 40px;
}

/* ==========================================
   CATEGORIES
   ========================================== */
.categories {
    background: var(--white);
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.category-card {
    background: var(--gray-100);
    border-radius: var(--radius-lg);
    padding: 30px;
    text-align: center;
    transition: var(--transition);
    border: 2px solid transparent;
}

.category-card:hover {
    background: var(--white);
    border-color: var(--primary);
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.category-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.category-card h3 {
    font-size: 1.3rem;
    margin-bottom: 8px;
    color: var(--dark);
}

.category-card p {
    color: var(--gray-500);
    font-size: 0.9rem;
}

/* ==========================================
   COURSES GRID
   ========================================== */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.course-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.course-image {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.course-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.course-card:hover .course-image img {
    transform: scale(1.05);
}

.course-badge {
    position: absolute;
    top: 15px;
    right: 15px;
    background: var(--secondary);
    color: var(--white);
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.course-badge.free {
    background: var(--accent);
}

.course-content {
    padding: 20px;
}

.course-category {
    display: inline-block;
    background: var(--primary-light);
    color: var(--white);
    padding: 4px 12px;
    border-radius: 15px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.course-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--dark);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-instructor {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--gray-500);
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 15px;
    border-top: 1px solid var(--gray-200);
}

.course-price {
    font-size: 1.3rem;
    font-weight: 800;
    color: var(--primary);
}

.course-price.free {
    color: var(--secondary);
}

.course-duration {
    color: var(--gray-500);
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 5px;
}

/* Loading Spinner */
.loading-spinner {
    text-align: center;
    padding: 60px;
    grid-column: 1 / -1;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--gray-200);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

/* ==========================================
   FEATURES
   ========================================== */
.features {
    background: var(--white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.feature-card {
    text-align: center;
    padding: 30px;
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin: 0 auto 20px;
}

.feature-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--dark);
}

.feature-card p {
    color: var(--gray-500);
    font-size: 0.95rem;
}

/* ==========================================
   CTA SECTION
   ========================================== */
.cta {
    background: var(--gradient);
    text-align: center;
    color: var(--white);
}

.cta h2 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.cta p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

/* ==========================================
   FOOTER
   ========================================== */
.footer {
    background: var(--dark);
    color: var(--white);
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand p {
    color: var(--gray-400);
    margin-top: 15px;
}

.footer-links h4 {
    font-size: 1.1rem;
    margin-bottom: 20px;
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-links a {
    color: var(--gray-400);
}

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

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid var(--dark-light);
    color: var(--gray-500);
}

/* ==========================================
   RESPONSIVE
   ========================================== */
@media (max-width: 992px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-image {
        display: none;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .categories-grid,
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .courses-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 768px) {
    .nav-links,
    .nav-buttons {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .categories-grid,
    .courses-grid,
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 2rem;
    }
}