/* ===========================
   CSS Variables
   =========================== */
:root {
    --primary-color: #007AFF;
    --primary-hover: #0051D5;
    --secondary-color: #5856D6;
    --text-primary: #1D1D1F;
    --text-secondary: #6E6E73;
    --bg-primary: #FFFFFF;
    --bg-secondary: #F5F5F7;
    --bg-hero: #F9FAFB;
    --border-color: #D2D2D7;
    --success-color: #34C759;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.15);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

/* ===========================
   Reset & Base Styles
   =========================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===========================
   Typography
   =========================== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 3rem;
    font-weight: 700;
}

h2 {
    font-size: 2.5rem;
}

h3 {
    font-size: 1.75rem;
}

h4 {
    font-size: 1.5rem;
}

p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

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

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

/* ===========================
   Layout Components
   =========================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* ===========================
   Navigation Bar
   =========================== */
.navbar {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

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

.logo h1,
.logo a {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    background-color: var(--bg-secondary);
}

/* ===========================
   Hero Sections
   =========================== */
.hero {
    background: linear-gradient(135deg, var(--bg-hero) 0%, var(--bg-secondary) 100%);
    padding: 4rem 0;
    text-align: center;
}

.hero h2 {
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto;
}

.hero-secondary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.hero-secondary h2,
.hero-secondary .hero-subtitle {
    color: white;
}

/* Product Hero (Detailed Product Page) */
.product-hero {
    background: linear-gradient(135deg, var(--bg-hero) 0%, #E8F4FF 100%);
    padding: 5rem 0;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-text h1 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.hero-text h2 {
    color: var(--text-secondary);
    font-size: 1.5rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.hero-actions {
    margin: 2rem 0;
}

.hero-meta {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.hero-image img {
    max-width: 350px;
    width: 100%;
    height: auto;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

/* ===========================
   Buttons
   =========================== */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    text-align: center;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    border: none;
    text-decoration: none;
}

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

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

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

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

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

/* ===========================
   Tab Content
   =========================== */
.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* ===========================
   Products Section
   =========================== */
.products-section {
    padding: 4rem 0;
}

.product-card {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

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

.product-card.coming-soon {
    opacity: 0.7;
}

.product-icon img {
    width: 100px;
    height: 100px;
    border-radius: var(--radius-md);
    margin-bottom: 1.5rem;
}

.product-info h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.product-description {
    font-size: 1.125rem;
    margin-bottom: 1.5rem;
}

.product-features ul {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.product-features li {
    color: var(--text-secondary);
    font-size: 1rem;
}

.product-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* ===========================
   Features Section
   =========================== */
.features-section {
    padding: 5rem 0;
    background-color: var(--bg-secondary);
}

.section-title {
    text-align: center;
    color: var(--text-primary);
    margin-bottom: 3rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

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

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

.feature-card p {
    font-size: 0.95rem;
}

/* ===========================
   How It Works Section
   =========================== */
.how-it-works {
    padding: 5rem 0;
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.step-card {
    text-align: center;
    padding: 2rem;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    font-size: 1.5rem;
    font-weight: 700;
    border-radius: 50%;
    margin-bottom: 1.5rem;
}

.step-card h3 {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

/* ===========================
   Pricing Section
   =========================== */
.pricing-section {
    padding: 5rem 0;
    background-color: var(--bg-secondary);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.pricing-card {
    background: white;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    text-align: center;
    transition: var(--transition);
    position: relative;
}

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

.pricing-featured {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.featured-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--primary-color);
    color: white;
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
}

.pricing-card h3 {
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.price {
    margin-bottom: 2rem;
}

.price-amount {
    display: block;
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-primary);
}

.price-period {
    display: block;
    color: var(--text-secondary);
    font-size: 1rem;
}

.pricing-features {
    list-style: none;
    text-align: left;
    margin-bottom: 2rem;
}

.pricing-features li {
    padding: 0.5rem 0;
    color: var(--text-secondary);
}

/* ===========================
   FAQ Section
   =========================== */
.faq-section {
    padding: 5rem 0;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.faq-item {
    padding: 1.5rem;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
}

.faq-item h3 {
    color: var(--text-primary);
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.faq-item p {
    font-size: 0.95rem;
}

/* ===========================
   User Guide Section
   =========================== */
.user-guide-section {
    padding: 5rem 0;
    background-color: var(--bg-primary);
}

.guide-intro {
    text-align: center;
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
}

.guide-content {
    max-width: 1000px;
    margin: 0 auto;
}

.guide-section {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-sm);
}

.guide-section h3 {
    color: var(--text-primary);
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--bg-secondary);
}

.guide-steps {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.guide-step {
    padding-left: 1.5rem;
    border-left: 3px solid var(--primary-color);
}

.guide-step h4 {
    color: var(--text-primary);
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.guide-step p {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: 0.5rem;
}

.guide-step ul {
    margin: 0.75rem 0 0.75rem 1.5rem;
    color: var(--text-secondary);
}

.guide-step li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.guide-step strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* Tips Grid */
.guide-tips {
    background: linear-gradient(135deg, var(--bg-hero) 0%, var(--bg-secondary) 100%);
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.tip-card {
    background: white;
    padding: 1.5rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.tip-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.tip-card h4 {
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.tip-card p {
    font-size: 0.95rem;
    margin: 0;
}

/* Screenshot Containers */
.screenshot-container {
    margin: 1.5rem auto;
    text-align: center;
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: var(--radius-md);
    max-width: 400px;
}

.guide-screenshot {
    max-width: 100%;
    width: 300px;
    height: auto;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.screenshot-caption {
    margin-top: 1rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-style: italic;
}

/* ===========================
   CTA Section
   =========================== */
.cta-section {
    padding: 5rem 0;
    text-align: center;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

.cta-section h2 {
    color: white;
    margin-bottom: 1rem;
}

.cta-section p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.25rem;
    margin-bottom: 2rem;
}

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

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

/* ===========================
   About Section
   =========================== */
.about-section {
    padding: 4rem 0;
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-content h3 {
    color: var(--text-primary);
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.about-content p {
    font-size: 1.125rem;
    line-height: 1.8;
}

.about-values {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.value-card {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: var(--radius-md);
}

.value-card h4 {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

.value-card p {
    font-size: 0.95rem;
}

.contact-info {
    margin-top: 3rem;
    padding: 2rem;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    text-align: center;
}

/* ===========================
   Legal Content
   =========================== */
.legal-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 4rem 2rem;
}

.legal-content h1 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.updated-date {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 3rem;
}

.legal-section {
    margin-bottom: 3rem;
}

.legal-section h2 {
    color: var(--text-primary);
    font-size: 1.75rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.legal-section h3 {
    color: var(--text-primary);
    font-size: 1.25rem;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}

.legal-section ul {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

.legal-section li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.legal-section p {
    font-size: 1rem;
    line-height: 1.8;
}

.privacy-summary {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: var(--radius-md);
    border-left: 4px solid var(--primary-color);
}

.privacy-summary ul {
    margin-left: 1.5rem;
}

/* ===========================
   Footer
   =========================== */
footer {
    background-color: var(--text-primary);
    color: white;
    padding: 3rem 0 2rem;
    margin-top: 4rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 2rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.95rem;
    transition: var(--transition);
}

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

.footer-copyright {
    color: rgba(255, 255, 255, 0.6);
}

.footer-copyright p {
    color: rgba(255, 255, 255, 0.6);
    margin: 0;
}

/* ===========================
   Responsive Design
   =========================== */
@media (max-width: 768px) {
    html {
        font-size: 14px;
    }

    .container {
        padding: 0 1.5rem;
    }

    .navbar .container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-menu {
        gap: 1rem;
    }

    .hero-content {
        grid-template-columns: 1fr;
    }

    .hero-image {
        order: -1;
    }

    h1 {
        font-size: 2.25rem;
    }

    h2 {
        font-size: 1.75rem;
    }

    .features-grid,
    .pricing-grid,
    .steps-grid,
    .faq-grid,
    .tips-grid {
        grid-template-columns: 1fr;
    }

    .product-actions {
        flex-direction: column;
    }

    .product-actions .btn {
        width: 100%;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }

    /* User Guide Responsive */
    .guide-section {
        padding: 1.5rem;
    }

    .guide-section h3 {
        font-size: 1.5rem;
    }

    .guide-step {
        padding-left: 1rem;
    }

    .guide-step h4 {
        font-size: 1.1rem;
    }

    /* Screenshots on mobile */
    .screenshot-container {
        padding: 1rem;
        max-width: 100%;
    }

    .guide-screenshot {
        width: 250px;
        max-width: 100%;
    }

    .hero-image img {
        max-width: 280px;
    }
}

@media (max-width: 480px) {
    .hero-meta {
        flex-direction: column;
        gap: 0.5rem;
    }

    .btn-large {
        padding: 0.875rem 1.5rem;
        font-size: 1rem;
    }

    /* Screenshots on small mobile */
    .guide-screenshot {
        width: 220px;
    }

    .hero-image img {
        max-width: 240px;
    }
}

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

.tab-content.active {
    animation: fadeIn 0.5s ease;
}

/* ===========================
   Utility Classes
   =========================== */
.text-center {
    text-align: center;
}

.mt-2 {
    margin-top: 2rem;
}

.mb-2 {
    margin-bottom: 2rem;
}

.hidden {
    display: none;
}