/* ============================================
   Global Styles & Variables
   ============================================ */

:root {
    --primary-color: #1e293b;
    --secondary-color: #64748b;
    --accent-color: #06b6d4;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --border-color: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-color);
    line-height: 1.6;
}

/* ============================================
   Container & Layout
   ============================================ */

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

/* ============================================
   Navigation Bar
   ============================================ */

.navbar {
    background: var(--card-bg);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.logo i {
    color: var(--accent-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--accent-color);
}

.nav-menu a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background-color: var(--accent-color);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 5px 0;
    transition: var(--transition);
}

/* ============================================
   Buttons
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: var(--transition);
    text-align: center;
}

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

.btn-primary:hover {
    background-color: #0891b2;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

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

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

.btn-lg {
    padding: 14px 32px;
    font-size: 18px;
}

.btn-small {
    padding: 8px 16px;
    font-size: 14px;
}

.btn-full-width {
    width: 100%;
    justify-content: center;
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, #334155 100%);
    color: white;
    padding: 100px 0;
    position: relative;
    overflow: hidden;
}

.stars {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    animation: twinkle 3s ease-in-out infinite;
}

@keyframes twinkle {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.6; }
}

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

.hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    animation: slideIn 0.8s ease;
}

.hero-subtitle {
    font-size: 20px;
    margin-bottom: 40px;
    opacity: 0.9;
    animation: slideIn 0.8s ease 0.2s backwards;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    animation: slideIn 0.8s ease 0.4s backwards;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ============================================
   Section Titles
   ============================================ */

.section-title {
    text-align: center;
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 50px;
    color: var(--primary-color);
}

/* ============================================
   Features Section
   ============================================ */

.features {
    padding: 80px 0;
    background-color: var(--bg-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.feature-card {
    background: var(--card-bg);
    padding: 40px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    text-align: center;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 48px;
    color: var(--accent-color);
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--primary-color);
}

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

/* ============================================
   Quick Download Section
   ============================================ */

.quick-download {
    padding: 80px 0;
    background-color: white;
}

.platform-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.platform-card {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    border: 2px solid var(--border-color);
    transition: var(--transition);
    cursor: pointer;
}

.platform-card:hover {
    border-color: var(--accent-color);
    box-shadow: var(--shadow-md);
    transform: translateY(-5px);
}

.platform-icon {
    font-size: 48px;
    margin-bottom: 15px;
    color: var(--accent-color);
}

.platform-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.platform-card p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 20px;
}

/* Platform specific colors */
.platform-card.windows { border-top: 4px solid #0078d4; }
.platform-card.android { border-top: 4px solid #3ddc84; }
.platform-card.mac { border-top: 4px solid #555555; }
.platform-card.ios { border-top: 4px solid #000000; }
.platform-card.linux { border-top: 4px solid #fcc624; }
.platform-card.web { border-top: 4px solid #f97316; }

/* ============================================
   Stats Section
   ============================================ */

.stats {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, #334155 100%);
    color: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    text-align: center;
}

.stat-number {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 10px;
}

.stat-label {
    font-size: 16px;
    opacity: 0.9;
}

/* ============================================
   CTA Section
   ============================================ */

.cta {
    padding: 80px 0;
    background-color: white;
    text-align: center;
}

.cta h2 {
    font-size: 36px;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.cta p {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

/* ============================================
   Page Header
   ============================================ */

.page-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, #334155 100%);
    color: white;
    padding: 60px 0;
    text-align: center;
}

.page-header h1 {
    font-size: 40px;
    margin-bottom: 15px;
}

.page-header p {
    font-size: 18px;
    opacity: 0.9;
}

/* ============================================
   Download Section
   ============================================ */

.downloads {
    padding: 60px 0;
}

.download-list {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.download-item {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.download-header {
    padding: 30px;
    color: white;
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 24px;
}

.download-header i {
    font-size: 36px;
}

.download-header h2 {
    margin: 0;
}

.windows-bg { background: linear-gradient(135deg, #0078d4 0%, #1b9adb 100%); }
.mac-bg { background: linear-gradient(135deg, #555555 0%, #303030 100%); }
.android-bg { background: linear-gradient(135deg, #3ddc84 0%, #2dc44e 100%); }
.ios-bg { background: linear-gradient(135deg, #000000 0%, #333333 100%); }
.linux-bg { background: linear-gradient(135deg, #fcc624 0%, #ffb81c 100%); }

.download-body {
    padding: 30px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.app-box {
    border: 1px solid var(--border-color);
    padding: 20px;
    border-radius: 8px;
    transition: var(--transition);
}

.app-box:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--accent-color);
}

.app-box h3 {
    margin-bottom: 10px;
    color: var(--primary-color);
}

.version {
    color: var(--accent-color);
    font-size: 14px;
    margin-bottom: 10px;
}

.description {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 20px;
}

.download-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

/* ============================================
   Tutorial Section
   ============================================ */

.tutorials {
    padding: 60px 0;
}

.tutorials-content {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 40px;
}

.tutorial-sidebar {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 12px;
    height: fit-content;
    box-shadow: var(--shadow-sm);
}

.toc-title {
    font-weight: 700;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.toc-list {
    list-style: none;
}

.toc-list li {
    margin-bottom: 10px;
}

.toc-list a {
    color: var(--text-secondary);
    text-decoration: none;
    display: block;
    padding: 8px 0;
    border-left: 3px solid transparent;
    padding-left: 10px;
    transition: var(--transition);
}

.toc-list a:hover {
    color: var(--accent-color);
    border-left-color: var(--accent-color);
}

.tutorial-main {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 12px;
}

.tutorial-article {
    margin-bottom: 40px;
}

.tutorial-article h2 {
    font-size: 24px;
    margin-bottom: 20px;
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.tutorial-article h3 {
    font-size: 18px;
    margin-top: 20px;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.feature-list {
    list-style: none;
    margin-bottom: 20px;
}

.feature-list li {
    padding: 10px 0;
    padding-left: 25px;
    position: relative;
    color: var(--text-secondary);
}

.feature-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success-color);
    font-weight: 700;
}

.steps {
    list-style: decimal;
    margin-left: 20px;
    margin-bottom: 20px;
}

.steps li {
    margin-bottom: 10px;
    color: var(--text-secondary);
}

.rules-table {
    overflow-x: auto;
    margin: 20px 0;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

th {
    background-color: var(--primary-color);
    color: white;
    padding: 12px;
    text-align: left;
    font-weight: 600;
}

td {
    padding: 12px;
    border-bottom: 1px solid var(--border-color);
}

tr:hover {
    background-color: var(--bg-color);
}

.faq-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.faq-item {
    background: var(--bg-color);
    padding: 20px;
    border-radius: 8px;
    border-left: 4px solid var(--accent-color);
}

.faq-item h4 {
    margin-bottom: 10px;
    color: var(--primary-color);
}

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

/* ============================================
   Airport Section
   ============================================ */

.filter-section {
    padding: 40px 0;
    text-align: center;
}

.filter-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 10px 20px;
    border: 2px solid var(--border-color);
    background: white;
    border-radius: 25px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
    color: var(--text-secondary);
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.airports {
    padding: 40px 0;
}

.airport-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 25px;
}

.airport-card {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.airport-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.airport-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.airport-header h3 {
    margin: 0;
    font-size: 20px;
}

.badge {
    display: inline-block;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    background: rgba(255, 255, 255, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.badge.premium { background: rgba(255, 215, 0, 0.3); border-color: #ffd700; }
.badge.affordable { background: rgba(34, 197, 94, 0.3); border-color: #22c55e; }
.badge.free { background: rgba(59, 130, 246, 0.3); border-color: #3b82f6; }

.airport-content {
    padding: 20px;
}

.airport-info {
    margin-bottom: 20px;
}

.airport-info p {
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.airport-info i {
    color: var(--accent-color);
    width: 16px;
}

.airport-price {
    display: flex;
    gap: 10px;
    align-items: center;
    margin-bottom: 20px;
    font-size: 16px;
    font-weight: 700;
}

.original-price {
    text-decoration: line-through;
    color: var(--text-secondary);
    font-size: 14px;
}

.current-price {
    color: var(--accent-color);
    font-size: 20px;
}

.airport-features {
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    padding: 15px 0;
    margin-bottom: 15px;
}

.feature {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.feature::before {
    content: '✓ ';
    color: var(--success-color);
    font-weight: 700;
}

.airport-buttons {
    display: flex;
    gap: 10px;
}

.comparison {
    padding: 60px 0;
    background-color: var(--bg-color);
}

.comparison-table-wrapper {
    overflow-x: auto;
}

.comparison-table {
    width: 100%;
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

/* ============================================
   Footer
   ============================================ */

.footer {
    background: var(--primary-color);
    color: white;
    padding: 60px 0 20px;
    margin-top: 80px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    margin-bottom: 20px;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
    line-height: 1.8;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
}

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

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    font-size: 18px;
}

.social-links a:hover {
    background: var(--accent-color);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 20px;
    text-align: center;
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

.footer-bottom a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer-bottom a:hover {
    color: var(--accent-color);
}