/* ============================================================================
   Invzen Landing Page Styles
   Design System Based on Invoico Frontend Demo
   ============================================================================ */

/* ============================================================================
   CSS Reset & Base Styles
   ============================================================================ */

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

:root {
    /* Color System - Light Theme (Default) */
    --color-primary-50: #eff6ff;
    --color-primary-100: #dbeafe;
    --color-primary-500: #3b82f6;
    --color-primary-600: #2563eb;
    --color-primary-700: #1d4ed8;

    --color-success-500: #22c55e;
    --color-success-600: #16a34a;

    --color-neutral-0: #ffffff;
    --color-neutral-50: #fafafa;
    --color-neutral-100: #f5f5f5;
    --color-neutral-200: #e5e5e5;
    --color-neutral-300: #d4d4d4;
    --color-neutral-400: #a3a3a3;
    --color-neutral-500: #737373;
    --color-neutral-600: #525252;
    --color-neutral-700: #404040;
    --color-neutral-800: #262626;
    --color-neutral-900: #171717;

    /* Semantic Tokens */
    --color-background: var(--color-neutral-0);
    --color-background-secondary: var(--color-neutral-50);
    --color-background-tertiary: var(--color-neutral-100);
    --color-text-primary: var(--color-neutral-900);
    --color-text-secondary: var(--color-neutral-600);
    --color-text-tertiary: var(--color-neutral-500);
    --color-border: var(--color-neutral-300);

    /* Typography System */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-secondary: 'Merriweather', 'Georgia', serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

    /* Type Scale */
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;
    --text-6xl: 3.75rem;

    /* Spacing System */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;

    /* 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);

    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;

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

    /* Layout */
    --max-width: 1280px;
    --header-height: 4rem;
}

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

body {
    font-family: var(--font-primary);
    font-size: var(--text-base);
    line-height: 1.5;
    color: var(--color-text-primary);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================================================
   Skip Link (Accessibility)
   ============================================================================ */

.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--color-primary-600);
    color: white;
    padding: var(--space-2) var(--space-4);
    text-decoration: none;
    border-radius: var(--radius-md);
    z-index: 9999;
}

.skip-link:focus {
    top: var(--space-2);
    left: var(--space-2);
}

/* ============================================================================
   Header & Navigation
   ============================================================================ */

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

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-6);
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.nav-brand {
    flex-shrink: 0;
}

.logo {
    font-size: var(--text-2xl);
    font-weight: 700;
    color: var(--color-primary-600);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--space-6);
    align-items: center;
}

.nav-link {
    color: var(--color-text-primary);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--text-sm);
    transition: color var(--transition-fast);
    padding: var(--space-2) 0;
}

.nav-link:hover,
.nav-link:focus {
    color: var(--color-primary-600);
}

.nav-actions {
    display: flex;
    gap: var(--space-4);
    align-items: center;
}

.mobile-menu-toggle {
    display: none;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-family: var(--font-primary);
    font-weight: 600;
    font-size: var(--text-sm);
    letter-spacing: 0.02em;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.btn-primary {
    background-color: var(--color-primary-600);
    color: white;
}

.btn-primary:hover,
.btn-primary:focus {
    background-color: var(--color-primary-700);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-primary-600);
    border: 1px solid var(--color-primary-600);
}

.btn-secondary:hover,
.btn-secondary:focus {
    background-color: var(--color-primary-50);
}

.btn-large {
    padding: var(--space-4) var(--space-8);
    font-size: var(--text-base);
}

.btn-block {
    width: 100%;
}

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

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

.section {
    padding: var(--space-20) 0;
}

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

.section-dark {
    background-color: var(--color-neutral-900);
    color: white;
}

.section-dark .section-title,
.section-dark .feature-title {
    color: white;
}

.section-dark .section-description,
.section-dark .feature-description {
    color: var(--color-neutral-300);
}

.section-header {
    text-align: center;
    max-width: 800px;
    margin: 0 auto var(--space-16);
}

.section-title {
    font-size: var(--text-4xl);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--space-4);
    color: var(--color-text-primary);
}

.section-description {
    font-size: var(--text-lg);
    line-height: 1.6;
    color: var(--color-text-secondary);
}

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

.hero {
    padding: var(--space-24) 0 var(--space-20);
    background: linear-gradient(135deg, var(--color-primary-50) 0%, var(--color-neutral-0) 100%);
}

.hero-content {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.hero-title {
    font-size: clamp(var(--text-4xl), 5vw, var(--text-6xl));
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--space-6);
    color: var(--color-text-primary);
}

.hero-subtitle {
    display: block;
    color: var(--color-primary-600);
    margin-top: var(--space-4);
}

.hero-description {
    font-size: var(--text-xl);
    line-height: 1.6;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-8);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--space-6);
}

.hero-trust {
    font-size: var(--text-sm);
    color: var(--color-text-tertiary);
}

/* ============================================================================
   Trust Section
   ============================================================================ */

.trust-section {
    background-color: var(--color-background-secondary);
    padding: var(--space-16) 0;
}

.trust-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-8);
    text-align: center;
}

.trust-stat {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.stat-number {
    font-size: var(--text-4xl);
    font-weight: 700;
    color: var(--color-primary-600);
}

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

/* ============================================================================
   Features Grid
   ============================================================================ */

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--space-8);
}

.feature-card {
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    transition: all var(--transition-base);
}

.feature-card:hover {
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary-200);
}

.feature-icon {
    font-size: var(--text-5xl);
    margin-bottom: var(--space-4);
}

.feature-title {
    font-size: var(--text-xl);
    font-weight: 600;
    margin-bottom: var(--space-3);
    color: var(--color-text-primary);
}

.feature-description {
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-4);
}

.feature-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.feature-list li {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    padding-left: var(--space-6);
    position: relative;
}

.feature-list li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--color-primary-600);
    font-weight: 700;
}

/* ============================================================================
   Developer Features
   ============================================================================ */

.developer-features {
    display: flex;
    flex-direction: column;
    gap: var(--space-16);
}

.developer-feature {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-12);
    align-items: center;
}

.developer-feature.reverse {
    direction: rtl;
}

.developer-feature.reverse > * {
    direction: ltr;
}

.developer-content {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

/* Monokai Pro Color Scheme */
.code-example {
    background-color: #2d2a2e;
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    overflow-x: auto;
}

.code-example pre {
    margin: 0;
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    line-height: 1.6;
}

.code-example code {
    color: #fcfcfa;
}

/* Monokai Pro Syntax Highlighting */
.code-example .keyword { color: #ff6188; } /* Keywords: import, const, await, function */
.code-example .string { color: #ffd866; } /* Strings */
.code-example .comment { color: #727072; font-style: italic; } /* Comments */
.code-example .function { color: #a9dc76; } /* Function names */
.code-example .variable { color: #78dce8; } /* Variables */
.code-example .property { color: #78dce8; } /* Object properties */
.code-example .number { color: #ab9df2; } /* Numbers */
.code-example .operator { color: #ff6188; } /* Operators */
.code-example .punctuation { color: #fcfcfa; } /* Punctuation */

.api-features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-6);
    width: 100%;
    grid-column: 1 / -1;
}

.api-feature {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
}

.api-feature h4 {
    font-size: var(--text-lg);
    margin-bottom: var(--space-3);
    color: white;
}

.api-feature p {
    font-size: var(--text-sm);
    line-height: 1.6;
    color: var(--color-neutral-300);
}

/* ============================================================================
   Pricing Section
   ============================================================================ */

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-8);
    max-width: 1200px;
    margin: 0 auto;
}

.pricing-card {
    background-color: var(--color-background);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-2xl);
    padding: var(--space-8);
    display: flex;
    flex-direction: column;
    position: relative;
    transition: all var(--transition-base);
}

/* Developer section API pricing cards - unified with api-feature styling */
.section-dark .api-pricing .pricing-card {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.section-dark .api-pricing .pricing-card:hover {
    background-color: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.section-dark .api-pricing .pricing-title {
    color: white;
}

.section-dark .api-pricing .pricing-subtitle {
    color: var(--color-neutral-300);
}

.section-dark .api-pricing .price-amount {
    color: white;
}

.section-dark .api-pricing .price-period {
    color: var(--color-neutral-300);
}

.section-dark .api-pricing .pricing-features li {
    color: white;
}

.section-dark .api-pricing h3 {
    color: white;
}

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

.pricing-card-featured {
    border-color: var(--color-primary-500);
    box-shadow: var(--shadow-lg);
}

.pricing-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--color-primary-600);
    color: white;
    padding: var(--space-1) var(--space-4);
    border-radius: var(--radius-lg);
    font-size: var(--text-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.pricing-header {
    margin-bottom: var(--space-6);
}

.pricing-title {
    font-size: var(--text-2xl);
    font-weight: 700;
    margin-bottom: var(--space-2);
}

.pricing-subtitle {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
}

.pricing-price {
    margin-bottom: var(--space-8);
}

.price-amount {
    font-size: var(--text-5xl);
    font-weight: 700;
    color: var(--color-primary-600);
}

.price-period {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
}

.pricing-features {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    margin-bottom: var(--space-8);
    flex-grow: 1;
}

.pricing-features li {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.pricing-features li span[aria-hidden="true"] {
    color: var(--color-success-500);
    font-weight: 700;
}

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

.cta-section {
    background: linear-gradient(135deg, var(--color-primary-600) 0%, var(--color-primary-700) 100%);
    padding: var(--space-20) 0;
    color: white;
}

.cta-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.cta-title {
    font-size: var(--text-5xl);
    font-weight: 700;
    margin-bottom: var(--space-4);
    color: white;
}

.cta-description {
    font-size: var(--text-xl);
    margin-bottom: var(--space-8);
    color: rgba(255, 255, 255, 0.9);
}

.cta-actions {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    flex-wrap: wrap;
}

.cta-section .btn-primary {
    background-color: white;
    color: var(--color-primary-600);
}

.cta-section .btn-primary:hover {
    background-color: var(--color-neutral-100);
}

.cta-section .btn-secondary {
    background-color: transparent;
    color: white;
    border-color: white;
}

.cta-section .btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

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

.footer {
    background-color: var(--color-neutral-900);
    color: var(--color-neutral-300);
    padding: var(--space-16) 0 var(--space-8);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-12);
    margin-bottom: var(--space-12);
}

.footer-column {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.footer-title {
    font-size: var(--text-2xl);
    font-weight: 700;
    color: white;
    margin-bottom: var(--space-2);
}

.footer-description {
    font-size: var(--text-sm);
    line-height: 1.6;
    color: var(--color-neutral-400);
}

.footer-heading {
    font-size: var(--text-lg);
    font-weight: 600;
    color: white;
    margin-bottom: var(--space-3);
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.footer-links a {
    color: var(--color-neutral-400);
    text-decoration: none;
    font-size: var(--text-sm);
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-neutral-800);
}

.footer-copyright {
    font-size: var(--text-sm);
    color: var(--color-neutral-500);
}

.footer-social {
    display: flex;
    gap: var(--space-6);
}

.social-link {
    color: var(--color-neutral-400);
    text-decoration: none;
    font-size: var(--text-sm);
    transition: color var(--transition-fast);
}

.social-link:hover,
.social-link:focus {
    color: white;
}

/* ============================================================================
   Responsive Design
   ============================================================================ */

@media (max-width: 1024px) {
    .developer-feature {
        grid-template-columns: 1fr;
    }

    .developer-feature.reverse {
        direction: ltr;
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 3.5rem;
    }

    .nav-menu {
        display: none;
    }

    .mobile-menu-toggle {
        display: block;
        background: none;
        border: none;
        cursor: pointer;
        padding: var(--space-2);
    }

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

    .section-title {
        font-size: var(--text-3xl);
    }

    .hero-title {
        font-size: var(--text-4xl);
    }

    .footer-bottom {
        flex-direction: column;
        gap: var(--space-4);
        text-align: center;
    }

    .pricing-grid {
        grid-template-columns: 1fr;
    }
}

/* ============================================================================
   Print Styles
   ============================================================================ */

@media print {
    .header,
    .footer,
    .btn,
    .cta-section {
        display: none;
    }
}

/* ============================================================================
   Accessibility - Reduced Motion
   ============================================================================ */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* ============================================================================
   Accessibility - High Contrast Mode
   ============================================================================ */

@media (prefers-contrast: high) {
    :root {
        --color-border: var(--color-neutral-900);
    }

    .btn {
        border: 2px solid currentColor;
    }

    .feature-card {
        border-width: 2px;
    }
}

/* ============================================================================
   Focus Styles (Accessibility)
   ============================================================================ */

*:focus {
    outline: 2px solid var(--color-primary-600);
    outline-offset: 2px;
}

*:focus:not(:focus-visible) {
    outline: none;
}

*:focus-visible {
    outline: 2px solid var(--color-primary-600);
    outline-offset: 2px;
}