/* BabyMo - AI Companion Chat App Styles */

/* ========================================
   CSS Variables & Reset
======================================== */
:root {
    /* Colors - Purple Night Theme */
    --primary: #8B5CF6;
    --primary-dark: #7C3AED;
    --primary-light: #A78BFA;
    --secondary: #EC4899;
    --secondary-dark: #DB2777;
    
    --bg-dark: #0a0a1a;
    --bg-dark-2: #12122a;
    --bg-card: rgba(255, 255, 255, 0.05);
    --bg-card-hover: rgba(255, 255, 255, 0.1);
    
    --text-primary: #ffffff;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    
    --gradient-primary: linear-gradient(135deg, #8B5CF6 0%, #EC4899 100%);
    --gradient-hero: linear-gradient(180deg, rgba(139, 92, 246, 0.2) 0%, rgba(10, 10, 26, 1) 100%);
    
    /* 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;
    --spacing-4xl: 6rem;
    
    /* Typography */
    --font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', 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: 3.5rem;
    
    /* Borders & Shadows */
    --radius-sm: 0.5rem;
    --radius-md: 1rem;
    --radius-lg: 1.5rem;
    --radius-xl: 2rem;
    --radius-full: 9999px;
    
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.2);
    --shadow-glow: 0 0 40px rgba(139, 92, 246, 0.3);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
    
    /* Layout */
    --max-width: 1200px;
    --nav-height: 70px;
}

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

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

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

ul, ol {
    list-style: none;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
}

/* ========================================
   Container
======================================== */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ========================================
   Navigation
======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    z-index: 1000;
    transition: var(--transition-base);
}

.navbar.scrolled {
    background: rgba(10, 10, 26, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-xl);
    font-weight: 700;
}

.nav-logo img {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
}

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

.nav-menu a {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    transition: var(--transition-fast);
    position: relative;
}

.nav-menu a:hover {
    color: var(--text-primary);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition-base);
}

.nav-menu a:hover::after {
    width: 100%;
}

.nav-cta {
    background: var(--gradient-primary);
    padding: var(--spacing-sm) var(--spacing-lg) !important;
    border-radius: var(--radius-full);
    color: white !important;
    font-weight: 500;
}

.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.nav-cta::after {
    display: none !important;
}

/* Mobile Navigation Toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: var(--spacing-sm);
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-base);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ========================================
   Hero Section
======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: var(--nav-height);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: -1;
}

.hero-bg img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.3;
}

.hero-bg::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-hero);
}

.hero-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--spacing-4xl) var(--spacing-lg);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-4xl);
    align-items: center;
}

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

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--spacing-lg);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

.hero-desc {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-2xl);
}

.hero-desc strong {
    color: var(--primary-light);
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-2xl);
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-full);
    font-size: var(--font-size-base);
    font-weight: 600;
    transition: var(--transition-base);
    cursor: pointer;
}

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

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 0 50px rgba(139, 92, 246, 0.5);
}

.btn-secondary {
    background: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.btn-secondary:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary);
}

.hero-stats {
    display: flex;
    gap: var(--spacing-2xl);
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-num {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--primary-light);
}

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

/* Hero Screenshots */
.hero-screenshots {
    position: relative;
}

.screenshot-stack {
    position: relative;
    width: 280px;
    margin: 0 auto;
}

.screenshot {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.main-screenshot {
    width: 240px;
    transform: rotate(-3deg);
    border: 3px solid rgba(255, 255, 255, 0.1);
}

.sub-screenshot {
    position: absolute;
    width: 200px;
    bottom: -30px;
    right: -40px;
    transform: rotate(5deg);
    border: 3px solid rgba(255, 255, 255, 0.1);
    z-index: -1;
}

/* Hero Wave */
.hero-wave {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 100px;
}

.hero-wave svg {
    width: 100%;
    height: 100%;
}

/* Hero Animations */
@keyframes slideFromLeft {
    from {
        opacity: 0;
        transform: translateX(-60px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideFromRight {
    from {
        opacity: 0;
        transform: translateX(60px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.slideFromLeft {
    animation: slideFromLeft 0.8s ease-out forwards;
}

.slideFromRight {
    animation: slideFromRight 0.8s ease-out forwards;
    animation-delay: 0.2s;
    opacity: 0;
}

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

.section-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.section-desc {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
}

/* ========================================
   Features Section
======================================== */
.features {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-dark);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    transition: var(--transition-base);
}

.feature-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-5px);
    border-color: var(--primary);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-lg);
}

.feature-icon svg {
    color: white;
}

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

.feature-desc {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Fade In Animation */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   Screenshots Section
======================================== */
.screenshots {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-dark-2);
}

.screenshots-slider {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
}

.screenshot-item {
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-lg);
    aspect-ratio: 9/16;
}

.screenshot-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-base);
}

.screenshot-item:hover img {
    transform: scale(1.05);
}

/* ========================================
   Guide Section
======================================== */
.guide {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-dark);
}

.guide-steps {
    display: flex;
    justify-content: space-between;
    gap: var(--spacing-xl);
    position: relative;
}

.guide-steps::before {
    content: '';
    position: absolute;
    top: 40px;
    left: 15%;
    right: 15%;
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    z-index: 0;
}

.guide-step {
    flex: 1;
    text-align: center;
    position: relative;
    z-index: 1;
}

.step-number {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    font-weight: 700;
    margin: 0 auto var(--spacing-lg);
    box-shadow: var(--shadow-glow);
}

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

.step-desc {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    max-width: 250px;
    margin: 0 auto;
}

/* ========================================
   Download Section
======================================== */
.download {
    padding: var(--spacing-4xl) 0;
    background: linear-gradient(180deg, var(--bg-dark) 0%, var(--bg-dark-2) 100%);
}

.download-content {
    text-align: center;
}

.download-title {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.download-desc {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-2xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.download-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg) var(--spacing-2xl);
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    transition: var(--transition-base);
    min-width: 220px;
}

.download-btn:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary);
    transform: translateY(-3px);
}

.download-btn svg {
    font-size: 32px;
}

.btn-text {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.btn-label {
    font-size: var(--font-size-base);
    font-weight: 600;
}

.btn-sub {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
}

.version-info {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
}

/* ========================================
   Reviews Section
======================================== */
.reviews {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-dark);
}

.reviews-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.review-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    transition: var(--transition-base);
}

.review-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-5px);
}

.review-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.review-avatar {
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: var(--font-size-lg);
}

.review-info {
    flex: 1;
}

.review-name {
    font-weight: 600;
    display: block;
    margin-bottom: 4px;
}

.review-stars {
    color: #fbbf24;
    font-size: var(--font-size-sm);
}

.review-text {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ========================================
   FAQ Section
======================================== */
.faq {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-dark-2);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.faq-question {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg) 0;
    font-size: var(--font-size-base);
    font-weight: 500;
    color: var(--text-primary);
    text-align: left;
    transition: var(--transition-fast);
}

.faq-question:hover {
    color: var(--primary-light);
}

.faq-question svg {
    transition: var(--transition-base);
    flex-shrink: 0;
}

.faq-item.active .faq-question svg {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 200px;
}

.faq-answer p {
    padding-bottom: var(--spacing-lg);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ========================================
   Footer
======================================== */
.footer {
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
    background: var(--bg-dark);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

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

.footer-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.footer-logo {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-sm);
}

.footer-info h3 {
    font-size: var(--font-size-lg);
    font-weight: 700;
}

.footer-info p {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
}

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

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

.footer-column ul li {
    margin-bottom: var(--spacing-sm);
}

.footer-column ul li a {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    transition: var(--transition-fast);
}

.footer-column ul li a:hover {
    color: var(--primary-light);
}

.footer-qr {
    text-align: center;
}

.footer-qr img {
    width: 120px;
    height: 120px;
    margin: 0 auto var(--spacing-sm);
    background: white;
    border-radius: var(--radius-sm);
    padding: var(--spacing-xs);
}

.footer-qr p {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-bottom p {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    margin-bottom: var(--spacing-xs);
}

.footer-bottom a {
    color: var(--primary-light);
    transition: var(--transition-fast);
}

.footer-bottom a:hover {
    text-decoration: underline;
}

/* ========================================
   Back to Top Button
======================================== */
.back-to-top {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-base);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-glow);
}

/* ========================================
   Responsive Design
======================================== */
@media (max-width: 968px) {
    :root {
        --font-size-4xl: 2rem;
        --font-size-5xl: 2.5rem;
    }
    
    /* Screen reader only - for SEO */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Navigation */
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: rgba(10, 10, 26, 0.98);
        backdrop-filter: blur(10px);
        flex-direction: column;
        padding: var(--spacing-xl);
        gap: var(--spacing-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition-base);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-cta {
        width: 100%;
        text-align: center;
        justify-content: center;
    }
    
    /* Hero */
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--spacing-2xl);
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .hero-screenshots {
        order: -1;
    }
    
    .screenshot-stack {
        width: 220px;
    }
    
    .main-screenshot {
        width: 180px;
    }
    
    .sub-screenshot {
        width: 150px;
        right: -20px;
    }
    
    /* Features */
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* Screenshots */
    .screenshots-slider {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* Guide */
    .guide-steps {
        flex-direction: column;
        gap: var(--spacing-2xl);
    }
    
    .guide-steps::before {
        display: none;
    }
    
    /* Reviews */
    .reviews-grid {
        grid-template-columns: 1fr;
    }
    
    /* Footer */
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-brand {
        justify-content: center;
    }
    
    .footer-links {
        justify-content: center;
    }
}

@media (max-width: 640px) {
    :root {
        --font-size-3xl: 1.75rem;
        --font-size-4xl: 1.5rem;
        --font-size-5xl: 2rem;
    }
    
    .container {
        padding: 0 var(--spacing-md);
    }
    
    /* Features */
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    /* Screenshots */
    .screenshots-slider {
        grid-template-columns: 1fr;
        max-width: 300px;
        margin: 0 auto;
    }
    
    /* Download */
    .download-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .download-btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }
    
    /* Back to top */
    .back-to-top {
        bottom: var(--spacing-md);
        right: var(--spacing-md);
        width: 40px;
        height: 40px;
    }
}