/* ===== CSS Variables ===== */
:root {
    /* Colors */
    --primary: #007AFF;
    --primary-dark: #0051D5;
    --secondary: #5856D6;
    --success: #34C759;
    --warning: #FF9500;
    --danger: #FF3B30;
    
    /* Grays */
    --gray-900: #1C1C1E;
    --gray-800: #2C2C2E;
    --gray-700: #3A3A3C;
    --gray-600: #48484A;
    --gray-500: #636366;
    --gray-400: #8E8E93;
    --gray-300: #C7C7CC;
    --gray-200: #E5E5EA;
    --gray-100: #F2F2F7;
    --white: #FFFFFF;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-hero: linear-gradient(135deg, #007AFF 0%, #5856D6 100%);
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, 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: 2rem;
    --font-size-4xl: 2.5rem;
    --font-size-5xl: 3rem;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 9999px;
    
    /* 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);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

/* ===== Dark Mode Variables ===== */
@media (prefers-color-scheme: dark) {
    :root {
        --gray-900: #F2F2F7;
        --gray-800: #E5E5EA;
        --gray-700: #C7C7CC;
        --gray-600: #8E8E93;
        --gray-500: #636366;
        --gray-400: #48484A;
        --gray-300: #3A3A3C;
        --gray-200: #2C2C2E;
        --gray-100: #1C1C1E;
        --white: #000000;
    }
}

/* ===== Global Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--gray-900);
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

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

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

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

/* ===== Header ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--gray-200);
    z-index: 1000;
    transition: all 0.3s ease;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
}

.logo-text {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--gray-900);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-link {
    color: var(--gray-700);
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.language-selector {
    position: relative;
    display: inline-block;
}

.language-dropdown {
    appearance: none;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.98), rgba(248, 250, 252, 0.98));
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 122, 255, 0.15);
    border-radius: var(--radius-full);
    padding: 8px 36px 8px 16px;
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-800);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    min-width: 100px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    position: relative;
}

.language-dropdown:hover {
    border-color: var(--primary);
    background: linear-gradient(135deg, var(--white), var(--gray-50));
    box-shadow: 0 4px 12px rgba(0, 122, 255, 0.15);
    transform: translateY(-1px);
}

.language-dropdown:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.1), 0 4px 12px rgba(0, 122, 255, 0.15);
}

.language-selector::after {
    content: '';
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    width: 0;
    height: 0;
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    border-top: 5px solid var(--gray-500);
    pointer-events: none;
    transition: border-color 0.3s ease;
}

.language-dropdown:hover ~ .language-selector::after,
.language-selector:hover::after {
    border-top-color: var(--primary);
}

.language-dropdown option {
    background: white;
    color: var(--gray-900);
    font-weight: 500;
    padding: 8px 12px;
    font-size: 14px;
}

.language-dropdown option:hover {
    background: var(--gray-50);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-sm);
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--gray-700);
    transition: all 0.3s ease;
}

/* ===== Hero Section ===== */
.hero {
    padding-top: calc(72px + var(--spacing-3xl));
    padding-bottom: var(--spacing-3xl);
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    position: relative;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 50%, rgba(0, 122, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 50%, rgba(88, 86, 214, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 600;
    color: var(--gray-800);
    margin-bottom: var(--spacing-lg);
}

.hero-description {
    font-size: var(--font-size-lg);
    color: var(--gray-600);
    margin-bottom: var(--spacing-xl);
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-lg);
    font-weight: 600;
    font-size: var(--font-size-base);
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--gradient-hero);
    color: white;
    box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
    color: white;
}

.btn-secondary {
    background: var(--white);
    color: var(--gray-700);
    border: 2px solid var(--gray-200);
}

.btn-secondary:hover {
    background: var(--gray-100);
    border-color: var(--gray-300);
    color: var(--gray-900);
}

.btn-icon {
    width: 20px;
    height: 20px;
}

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

.hero-meta {
    display: flex;
    gap: var(--spacing-lg);
}

.meta-item {
    font-size: var(--font-size-sm);
    color: var(--gray-500);
}

.hero-image {
    position: relative;
}

.hero-screenshot {
    width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 
        0 0 0 1px rgba(0, 0, 0, 0.05),
        0 10px 40px rgba(0, 0, 0, 0.1),
        0 30px 80px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.hero-image:hover .hero-screenshot {
    transform: translateY(-4px) scale(1.01);
    box-shadow: 
        0 0 0 1px rgba(0, 0, 0, 0.05),
        0 15px 50px rgba(0, 0, 0, 0.15),
        0 40px 100px rgba(0, 0, 0, 0.12);
}

/* ===== Section Headers ===== */
.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: var(--spacing-md);
}

.section-subtitle {
    font-size: var(--font-size-lg);
    color: var(--gray-600);
}

/* ===== Features Section ===== */
.features {
    padding: var(--spacing-3xl) 0;
    background: #f8fafb;
}

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

.feature-card {
    padding: var(--spacing-xl);
    background: var(--white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--gray-200);
    transition: all 0.3s ease;
}

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

.feature-icon {
    width: 48px;
    height: 48px;
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-sm);
    background: var(--gradient-hero);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    stroke: white;
}

.feature-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.feature-description {
    color: var(--gray-600);
    line-height: 1.6;
}

/* ===== Screenshots Section ===== */
.screenshots {
    padding: var(--spacing-3xl) 0;
    background: white;
}

.screenshots-carousel {
    position: relative;
    overflow: hidden;
    max-width: 900px;
    margin: 0 auto;
    background: transparent;
}

.screenshots-container {
    display: flex;
    transition: transform 0.5s ease;
}

.screenshot-item {
    min-width: 100%;
    padding: 0;
}

.screenshot-item img {
    width: 100%;
    height: auto;
    display: block;
}

.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255, 255, 255, 0.9);
    border: none;
    border-radius: var(--radius-full);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-lg);
}

.carousel-btn:hover {
    background: white;
    transform: translateY(-50%) scale(1.1);
}

.carousel-prev { left: var(--spacing-lg); }
.carousel-next { right: var(--spacing-lg); }

.screenshot-dots {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-xl);
}

.dot {
    width: 8px;
    height: 8px;
    border-radius: var(--radius-full);
    background: var(--gray-400);
    cursor: pointer;
    transition: all 0.3s ease;
}

.dot.active {
    width: 24px;
    background: var(--primary);
}

/* ===== Beta Badge ===== */
.beta-badge {
    display: inline-block;
    margin-bottom: var(--spacing-md);
}

.beta-badge span {
    background: linear-gradient(135deg, var(--warning), #FF6B35);
    color: white;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.beta-notice {
    background: linear-gradient(135deg, rgba(255, 149, 0, 0.1), rgba(255, 107, 53, 0.1));
    border-left: 3px solid var(--warning);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-xl);
    font-size: var(--font-size-base);
    color: var(--gray-700);
}

/* ===== Beta Section ===== */
.beta-section {
    padding: var(--spacing-3xl) 0;
    background: #f8fafb;
}

.beta-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.beta-card {
    padding: var(--spacing-2xl);
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.beta-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary);
}

.beta-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-lg);
    padding: var(--spacing-md);
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
}

.beta-icon svg {
    stroke: white;
    stroke-width: 1.5;
}

.beta-card h3 {
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.beta-card p {
    color: var(--gray-600);
    margin-bottom: var(--spacing-lg);
    line-height: 1.6;
}

.beta-info {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--gray-100);
    border-radius: var(--radius-lg);
    font-style: italic;
    color: var(--gray-600);
}

/* ===== Support Section ===== */
.support {
    padding: var(--spacing-3xl) 0;
    background: white;
}

.support-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
}

.support-card {
    padding: var(--spacing-xl);
    background: white;
    border-radius: var(--radius-lg);
    text-align: center;
    transition: all 0.3s ease;
}

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

.support-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--gradient-hero);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
}

.support-icon svg {
    stroke: white;
}

.support-card h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

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

.support-link {
    font-weight: 600;
    color: var(--primary);
}

/* ===== Lightbox ===== */
.lightbox {
    display: none;
    position: fixed;
    z-index: 10000;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.95);
    animation: fadeIn 0.3s;
}

.lightbox.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.lightbox-content {
    max-width: 90%;
    max-height: 85vh;
    width: auto;
    height: auto;
    object-fit: contain;
    border-radius: var(--radius-lg);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    animation: zoomIn 0.3s;
}

@keyframes zoomIn {
    from { transform: scale(0.8); opacity: 0; }
    to { transform: scale(1); opacity: 1; }
}

.lightbox-close {
    position: absolute;
    top: 30px;
    right: 40px;
    color: white;
    font-size: 40px;
    font-weight: 300;
    cursor: pointer;
    transition: all 0.2s;
    z-index: 10001;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.5);
    border-radius: 50%;
}

.lightbox-close:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: rotate(90deg);
}

.lightbox-caption {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    color: white;
    text-align: center;
    padding: 12px 24px;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-full);
    font-size: 14px;
}

.lightbox-prev,
.lightbox-next {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.2);
    font-size: 28px;
    padding: 16px 20px;
    cursor: pointer;
    border-radius: var(--radius);
    transition: all 0.2s;
}

.lightbox-prev:hover,
.lightbox-next:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-50%) scale(1.1);
}

.lightbox-prev {
    left: 30px;
}

.lightbox-next {
    right: 30px;
}

.screenshot-item {
    cursor: pointer;
    transition: transform 0.3s;
}

.screenshot-item:hover {
    transform: scale(1.02);
}

/* ===== Footer ===== */
.footer {
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
    background: var(--gray-900);
    color: var(--gray-200);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: var(--spacing-3xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-brand {
    max-width: 400px;
}

.footer-logo {
    width: 48px;
    height: 48px;
    margin-bottom: var(--spacing-md);
    border-radius: var(--radius-md);
}

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

.footer-links {
    display: flex;
    gap: var(--spacing-3xl);
}

.footer-column h4 {
    font-size: var(--font-size-base);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: white;
}

.footer-column a {
    display: block;
    color: var(--gray-400);
    margin-bottom: var(--spacing-sm);
    transition: color 0.3s ease;
}

.footer-column a:hover {
    color: white;
}

.footer-bottom {
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--gray-800);
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--gray-500);
    font-size: var(--font-size-sm);
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        padding: var(--spacing-lg);
        border-bottom: 1px solid var(--gray-200);
        box-shadow: var(--shadow-lg);
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-buttons {
        justify-content: center;
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .hero-image {
        order: -1;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        flex-direction: column;
        gap: var(--spacing-xl);
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }
    
    .carousel-btn {
        display: none;
    }
}

/* ===== Animations ===== */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in {
    animation: fadeIn 0.6s ease forwards;
}

/* ===== Loading State ===== */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid var(--gray-300);
    border-radius: 50%;
    border-top-color: var(--primary);
    animation: spin 1s ease-in-out infinite;
}

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