/* ============================================
   CSS Variables
   ============================================ */
:root {
    /* Colors */
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #10b981;
    --accent-color: #f59e0b;

    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;

    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-light: #f3f4f6;
    --bg-dark: #111827;

    --border-color: #e5e7eb;
    --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);

    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;

    /* Layout */
    --container-width: 1200px;
    --header-height: 70px;
}

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

html {
    scroll-behavior: smooth;
    font-size: var(--font-size-base);
}

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

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

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

ul {
    list-style: none;
}

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

/* ============================================
   Utility Classes
   ============================================ */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.section {
    padding: var(--spacing-2xl) 0;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.bg-light {
    background-color: var(--bg-secondary);
}

/* ============================================
   Header & Navigation
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--bg-primary);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: box-shadow var(--transition-base);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: var(--header-height);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-icon {
    font-size: 1.75rem;
}

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

.nav-link {
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-base);
    position: relative;
}

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

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--primary-color);
    border-radius: var(--radius-full);
}

.nav-toggle,
.nav-close {
    display: none;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 5px 0;
    transition: var(--transition-base);
    border-radius: var(--radius-full);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-block;
    padding: 0.875rem 1.75rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: all var(--transition-base);
    text-align: center;
    cursor: pointer;
}

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

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

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

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--bg-primary);
    transform: translateY(-2px);
}

.btn-large {
    padding: 1.125rem 2.25rem;
    font-size: 1.125rem;
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    padding-top: calc(var(--header-height) + var(--spacing-2xl));
    padding-bottom: var(--spacing-2xl);
    min-height: 100vh;
    display: flex;
    align-items: center;
}

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

.hero-content {
    animation: fadeInUp 0.8s ease-out;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.7;
}

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

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeInRight 0.8s ease-out;
}

.hero-illustration {
    position: relative;
    width: 100%;
    height: 400px;
}

.card-stack {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.card {
    position: absolute;
    width: 250px;
    height: 160px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    border-radius: var(--radius-xl);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 4rem;
    box-shadow: var(--shadow-xl);
    animation: float 3s ease-in-out infinite;
}

.card-1 {
    transform: rotate(-10deg) translateX(-30px);
    z-index: 3;
}

.card-2 {
    transform: rotate(5deg) translateY(20px);
    z-index: 2;
    background: linear-gradient(135deg, var(--secondary-color), #059669);
    animation-delay: 0.5s;
}

.card-3 {
    transform: rotate(-5deg) translateX(30px) translateY(-10px);
    z-index: 1;
    background: linear-gradient(135deg, var(--accent-color), #d97706);
    animation-delay: 1s;
}

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

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.section-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
}

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

.feature-card {
    background-color: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    border: 1px solid var(--border-color);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-light);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.feature-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.feature-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ============================================
   How It Works Section
   ============================================ */
.steps-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.step {
    text-align: center;
    position: relative;
}

.step-number {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--bg-primary);
    border-radius: var(--radius-full);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    font-weight: 700;
    margin: 0 auto var(--spacing-md);
    box-shadow: var(--shadow-lg);
}

.step-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.step-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ============================================
   Networks Section
   ============================================ */
.networks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
}

.network-badge {
    background-color: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    text-align: center;
    border: 2px solid var(--border-color);
    transition: all var(--transition-base);
}

.network-badge:hover {
    border-color: var(--primary-color);
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}

.network-name {
    font-weight: 600;
    font-size: 1.125rem;
    color: var(--text-primary);
}

/* ============================================
   CTA Section
   ============================================ */
.cta {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--bg-primary);
}

.cta-content {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.cta-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.cta-description {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-lg);
    opacity: 0.9;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

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

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

/* ============================================
   Footer
   ============================================ */
.footer {
    background-color: var(--bg-dark);
    color: var(--bg-secondary);
    padding: var(--spacing-2xl) 0 var(--spacing-md);
}

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

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.footer-description {
    color: var(--text-light);
    line-height: 1.7;
}

.footer-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

.footer-links a {
    color: var(--text-light);
    transition: color var(--transition-base);
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--spacing-md);
    text-align: center;
    color: var(--text-light);
}

/* ============================================
   Page Header (About & Privacy)
   ============================================ */
.page-header {
    padding-top: calc(var(--header-height) + var(--spacing-2xl));
    padding-bottom: var(--spacing-lg);
    text-align: center;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(16, 185, 129, 0.1));
}

.page-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.page-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
}

/* ============================================
   About Page Specific Styles
   ============================================ */
.content-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
}

.content-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.content-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

.about-illustration {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 300px;
}

.illustration-item {
    font-size: 12rem;
    animation: pulse 2s ease-in-out infinite;
}

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

.what-card {
    padding: var(--spacing-lg);
    text-align: center;
}

.what-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.what-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.what-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.value-item {
    padding: var(--spacing-lg);
}

.value-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.value-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

.story-content {
    max-width: 800px;
    margin: 0 auto;
}

.story-text {
    font-size: 1.125rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

/* ============================================
   Privacy Page Specific Styles
   ============================================ */
.privacy-wrapper {
    max-width: 900px;
    margin: 0 auto;
}

.privacy-section {
    margin-bottom: var(--spacing-xl);
}

.privacy-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.privacy-subtitle {
    font-size: 1.5rem;
    font-weight: 600;
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.privacy-text {
    font-size: 1.0625rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

.privacy-list {
    list-style: disc;
    margin-left: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.privacy-list li {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-xs);
}

.privacy-text a,
.privacy-list a {
    color: var(--primary-color);
    text-decoration: underline;
}

.privacy-text a:hover,
.privacy-list a:hover {
    color: var(--primary-dark);
}

.privacy-notice {
    background-color: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--primary-color);
    margin-top: var(--spacing-xl);
}

.privacy-notice p {
    color: var(--text-primary);
    font-size: 1.0625rem;
    line-height: 1.7;
}

/* ============================================
   Animations
   ============================================ */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@keyframes float {
    0%, 100% {
        transform: translateY(0) rotate(var(--rotation, 0deg));
    }
    50% {
        transform: translateY(-20px) rotate(var(--rotation, 0deg));
    }
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

/* ============================================
   Responsive Design
   ============================================ */
@media screen and (max-width: 968px) {
    :root {
        --font-size-base: 15px;
    }

    .hero-container,
    .content-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-image {
        order: -1;
    }

    .hero-illustration {
        height: 300px;
    }

    .card {
        width: 200px;
        height: 130px;
        font-size: 3rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .page-title {
        font-size: 2.5rem;
    }

    .cta-title {
        font-size: 2rem;
    }
}

@media screen and (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 350px;
        height: 100vh;
        background-color: var(--bg-primary);
        box-shadow: var(--shadow-xl);
        padding: var(--spacing-xl) var(--spacing-lg);
        transition: right var(--transition-slow);
        z-index: 1001;
    }

    .nav-menu.show {
        right: 0;
    }

    .nav-list {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }

    .nav-close {
        display: block;
        position: absolute;
        top: var(--spacing-md);
        right: var(--spacing-md);
        font-size: 2rem;
        color: var(--text-primary);
    }

    .nav-toggle {
        display: block;
    }

    .hero {
        padding-top: calc(var(--header-height) + var(--spacing-lg));
        min-height: auto;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-description {
        font-size: 1.125rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .hero-buttons .btn {
        width: 100%;
    }

    .features-grid,
    .steps-container,
    .networks-grid,
    .what-grid,
    .values-grid {
        grid-template-columns: 1fr;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .cta-title {
        font-size: 1.75rem;
    }

    .cta-description {
        font-size: 1.125rem;
    }

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

@media screen and (max-width: 480px) {
    .hero-title {
        font-size: 1.75rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .page-title {
        font-size: 2rem;
    }

    .btn {
        padding: 0.75rem 1.5rem;
    }

    .btn-large {
        padding: 1rem 1.75rem;
        font-size: 1rem;
    }

    .illustration-item {
        font-size: 8rem;
    }
}

/* ============================================
   Performance Optimizations
   ============================================ */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Print Styles */
@media print {
    .header,
    .nav-toggle,
    .hero-buttons,
    .cta,
    .footer {
        display: none;
    }

    body {
        font-size: 12pt;
    }
}