/* ============================================
   CSS VARIABLES - Design System
   ============================================ */

:root {
    /* NASA-Inspired Color System */
    --color-bg-primary: #ffffff;
    --color-bg-secondary: var(--color-bg-primary);
    --color-bg-tertiary: #f8f9fa;
    --color-bg-accent: #fffbf5;
    --color-bg-dark: #0b3d91;
    
    --color-text-primary: #0d1117;
    --color-text-secondary: #24292f;
    --color-text-tertiary: #57606a;
    --color-text-muted: #6e7781;
    
    /* NASA Mission Patch Palette */
    --color-accent-blue: #0b3d91;        /* NASA Blue */
    --color-accent-blue-bright: #1f5eb7;
    --color-accent-orange: #fc3d21;      /* Safety Orange */
    --color-accent-orange-dark: #d9321a;
    --color-accent-red: #dd361c;
    --color-accent-yellow: #ffbf3f;
    --color-accent-tech-green: #00cf5d;
    
    --color-border-light: #d0d7de;
    --color-border-medium: var(--color-border-light);
    --color-border-dark: #8c959f;
    
    --color-link: var(--color-accent-blue);
    --color-link-hover: var(--color-accent-blue-bright);
    
    --color-success: var(--color-accent-tech-green);
    
    /* Typography */
    --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    --font-heading: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', 'Consolas', 'Courier New', monospace;
    
    --font-size-xs: 0.75rem;      /* 12px */
    --font-size-sm: 0.875rem;     /* 14px */
    --font-size-base: 1.0625rem;  /* 17px */
    --font-size-lg: 1.25rem;      /* 20px */
    --font-size-xl: 1.375rem;     /* 22px */
    --font-size-2xl: 1.75rem;     /* 28px */
    --font-size-3xl: 2.25rem;     /* 36px */
    --font-size-4xl: 2.75rem;     /* 44px */
    --font-size-5xl: 3rem;        /* 48px */
    
    --line-height-tight: 1.2;
    --line-height-normal: 1.6;
    --line-height-relaxed: 1.75;
    
    /* Spacing Scale */
    --spacing-xs: 0.5rem;         /* 8px */
    --spacing-sm: 1rem;           /* 16px */
    --spacing-md: 1.5rem;         /* 24px */
    --spacing-lg: 2rem;           /* 32px */
    --spacing-xl: 3rem;           /* 48px */
    --spacing-2xl: 4rem;          /* 64px */
    --spacing-3xl: 6rem;          /* 96px */
    
    /* Border Radius */
    --radius-sm: 2px;
    --radius-md: 4px;
    --radius-lg: 8px;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05);
    
    /* Animation Timing */
    --duration-fast: 150ms;
    --duration-normal: 300ms;
    --duration-slow: 500ms;
    
    --easing-ease: ease;
    --easing-ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --easing-ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */

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

html {
    scroll-behavior: smooth;
}

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

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

/* ============================================
   LAYOUT STRUCTURE
   ============================================ */

.page-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-md);
}

@media (min-width: 768px) {
    .page-wrapper {
        padding: var(--spacing-2xl) var(--spacing-xl);
    }
}

/* ============================================
   HEADER
   ============================================ */

.site-header {
    margin-bottom: var(--spacing-2xl);
    padding-bottom: var(--spacing-xl);
    border-bottom: 4px solid var(--color-accent-blue);
    position: relative;
    animation: fadeInUp 0.6s var(--easing-ease-out);
}

.status-indicator {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 10px 18px;
    background-color: rgba(0, 207, 93, 0.1);
    border: 3px solid var(--color-success);
    border-radius: var(--radius-md);
    font-family: var(--font-heading);
    font-size: var(--font-size-xs);
    font-weight: 800;
    letter-spacing: 0.05em;
    color: var(--color-success);
    float: right;
    margin-left: var(--spacing-md);
}

.status-dot {
    width: 8px;
    height: 8px;
    background-color: var(--color-success);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.site-title {
    font-family: var(--font-heading);
    font-size: var(--font-size-4xl);
    font-weight: 800;
    line-height: var(--line-height-tight);
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-lg);
    letter-spacing: -0.02em;
    clear: both;
    text-transform: uppercase;
}

.site-title::after {
    content: "";
    display: table;
    clear: both;
}

.site-tagline {
    font-size: var(--font-size-lg);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
    max-width: 800px;
}

.site-subtitle {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-tertiary);
    max-width: 700px;
}

@media (min-width: 768px) {
    .site-title {
        font-size: var(--font-size-4xl);
    }
    
    .site-tagline {
        font-size: var(--font-size-xl);
    }
}

/* ============================================
   MAIN CONTENT
   ============================================ */

.main-content {
    flex: 1;
}

.content-section {
    margin-bottom: var(--spacing-2xl);
    padding: var(--spacing-xl);
    background-color: var(--color-bg-tertiary);
    border: 3px solid var(--color-border-medium);
    border-radius: var(--radius-sm);
    position: relative;
    animation: fadeInUp 0.6s var(--easing-ease-out);
    animation-fill-mode: both;
    transition: border-color var(--duration-normal) var(--easing-ease);
}

.content-section:hover {
    border-color: var(--color-accent-blue);
}

/* Staggered animation delays */
.content-section:nth-child(1) { animation-delay: 0s; }
.content-section:nth-child(2) { animation-delay: 0.1s; }
.content-section:nth-child(3) { animation-delay: 0.2s; }
.content-section:nth-child(4) { animation-delay: 0.3s; }
.content-section:nth-child(5) { animation-delay: 0.4s; }
.content-section:nth-child(6) { animation-delay: 0.5s; }
.content-section:nth-child(7) { animation-delay: 0.6s; }

@media (min-width: 768px) {
    .content-section {
        padding: var(--spacing-xl);
    }
}

/* Section Labels (NASA Technical Manual Style) */
.section-label {
    font-family: var(--font-heading);
    font-size: var(--font-size-xs);
    font-weight: 800;
    color: var(--color-accent-blue);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    display: inline-block;
    padding: 8px 14px;
    background-color: transparent;
    border: 3px solid var(--color-accent-blue);
    border-radius: var(--radius-sm);
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
}

.section-title {
    font-family: var(--font-heading);
    font-size: var(--font-size-2xl);
    font-weight: 800;
    line-height: var(--line-height-tight);
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-lg);
    letter-spacing: -0.005em;
    padding-right: 140px;
    text-transform: uppercase;
}

@media (min-width: 768px) {
    .status-indicator {
        margin-top: 4px;
    }
    
    .cta-section .section-label {
        top: var(--spacing-xl);
        right: var(--spacing-xl);
    }
}

@media (max-width: 767px) {
    .section-label {
        top: var(--spacing-md);
        right: var(--spacing-md);
        font-size: 0.65rem;
        padding: 6px 10px;
        border-width: 2px;
    }
    
    .content-section .section-title {
        padding-right: 110px;
        font-size: var(--font-size-xl);
    }
    
    .content-section {
        border-width: 2px;
    }
}

.section-intro {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-md);
    font-weight: 500;
}

.section-footer {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    margin-top: var(--spacing-xl);
    font-style: italic;
    font-weight: 500;
}

.content-section p {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-md);
    font-weight: 400;
}

.content-section p strong {
    font-weight: 700;
}

.content-section p:last-child {
    margin-bottom: 0;
}

/* ============================================
   LISTS
   ============================================ */

.feature-list,
.integration-list,
.benefits-list,
.monitoring-list,
.problems-list,
.steps-list {
    list-style: none;
    margin: var(--spacing-lg) 0;
}

/* Grid layout for feature lists - max 2 columns */
.feature-list,
.integration-list,
.benefits-list,
.monitoring-list,
.problems-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

@media (min-width: 768px) {
    .feature-list,
    .integration-list,
    .benefits-list,
    .monitoring-list,
    .problems-list {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Base list item styles */
.feature-list li,
.integration-list li,
.benefits-list li,
.monitoring-list li,
.problems-list li {
    position: relative;
    padding-left: var(--spacing-xl);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
}

.steps-list {
    max-width: 620px;
    margin-left: auto;
    margin-right: auto;
    text-align: left;
    margin-bottom: var(--spacing-2xl);
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.steps-list li {
    position: relative;
    padding-left: calc(48px + var(--spacing-md));
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
    font-weight: 500;
}

.feature-icon {
    position: absolute;
    left: 0;
    top: 0;
    font-size: var(--font-size-lg);
    line-height: var(--line-height-relaxed);
}

/* NASA-style filled checkbox markers - base styles */
.integration-list li::before,
.benefits-list li::before,
.monitoring-list li::before,
.problems-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 0.35em;
    width: 14px;
    height: 14px;
    border: 2px solid var(--color-accent-blue);
    background-color: var(--color-accent-blue);
    color: white;
    font-size: 10px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
    transition: transform var(--duration-fast) var(--easing-ease),
                box-shadow var(--duration-fast) var(--easing-ease);
}

/* Problems list - red X marks */
.problems-list li::before {
    content: '✕';
    border-color: var(--color-accent-red);
    background-color: var(--color-accent-red);
}

/* Hover effects */
.integration-list li:hover::before,
.benefits-list li:hover::before,
.monitoring-list li:hover::before {
    transform: scale(1.1);
    box-shadow: 0 0 0 2px rgba(11, 61, 145, 0.2);
}

.problems-list li:hover::before {
    transform: scale(1.1);
    box-shadow: 0 0 0 2px rgba(221, 54, 28, 0.2);
}

.steps-list li::before {
    content: counter(step-counter);
    counter-increment: step-counter;
    position: absolute;
    left: 0;
    top: -2px;
    font-family: var(--font-heading);
    font-size: var(--font-size-base);
    font-weight: 800;
    color: var(--color-accent-orange);
    background-color: transparent;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 3px solid var(--color-accent-orange);
    border-radius: var(--radius-sm);
}

.steps-list {
    counter-reset: step-counter;
}

/* ============================================
   APPLICATION AREAS SECTION
   ============================================ */

.use-case-categories {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

@media (min-width: 768px) {
    .use-case-categories {
        grid-template-columns: repeat(2, 1fr);
    }
}


.category-title {
    font-family: var(--font-heading);
    font-size: var(--font-size-base);
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-md);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.category-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.category-list li {
    position: relative;
    padding-left: var(--spacing-lg);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
}

.category-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 1em;
    width: 10px;
    height: 10px;
    border: 2px solid var(--color-accent-tech-green);
    background-color: var(--color-accent-tech-green);
    color: white;
    font-size: 8px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
    transition: transform var(--duration-fast) var(--easing-ease);
}

.category-list li:hover::before {
    transform: scale(1.1);
}

.use-case-footer {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
    font-style: italic;
    margin: 0;
    padding-top: var(--spacing-lg);
    border-top: 2px solid var(--color-border-light);
}

.use-case-footer strong {
    color: var(--color-text-primary);
    font-weight: 700;
    font-style: normal;
}

/* ============================================
   PRICING SECTION
   ============================================ */

.pricing-cards {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

@media (min-width: 768px) {
    .pricing-cards {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-md);
    }
}

.pricing-card {
    background-color: var(--color-bg-secondary);
    border: 3px solid var(--color-border-medium);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: transform var(--duration-normal) var(--easing-ease-out),
                box-shadow var(--duration-normal) var(--easing-ease-out),
                border-color var(--duration-normal) var(--easing-ease-out);
}

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

.pricing-card-featured {
    border-color: var(--color-accent-orange);
    border-width: 4px;
    background-color: var(--color-bg-secondary);
    position: relative;
}

.pricing-card-featured::before {
    content: 'RECOMMENDED';
    position: absolute;
    top: 28px;
    right: -34px;
    background-color: var(--color-accent-orange);
    color: var(--color-bg-secondary);
    font-family: var(--font-heading);
    font-size: var(--font-size-xs);
    font-weight: 800;
    letter-spacing: 0.08em;
    padding: 6px 36px;
    transform: rotate(45deg);
    box-shadow: var(--shadow-md);
    transform-origin: center;
}

.pricing-card-header {
    padding: var(--spacing-xl);
    border-bottom: 3px solid var(--color-border-medium);
    background-color: var(--color-bg-tertiary);
}

.pricing-tier {
    font-family: var(--font-heading);
    font-size: var(--font-size-sm);
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-accent-blue);
    margin-bottom: var(--spacing-sm);
}

.pricing-badge {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    color: var(--color-text-primary);
    font-family: var(--font-heading);
    letter-spacing: -0.02em;
}

.pricing-period {
    font-size: var(--font-size-base);
    color: var(--color-text-tertiary);
    font-weight: 400;
}

.pricing-card-body {
    padding: var(--spacing-lg);
}

.pricing-detail {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--color-border-light);
}

.pricing-detail:last-child {
    border-bottom: none;
}

.pricing-label {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    font-weight: 500;
}

.pricing-value {
    font-family: var(--font-heading);
    font-size: var(--font-size-base);
    font-weight: 700;
    color: var(--color-text-primary);
}

.pricing-contact {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    text-align: center;
    line-height: var(--line-height-relaxed);
    margin: 0;
}

/* ============================================
   LINKS
   ============================================ */

.inline-link {
    color: var(--color-link);
    text-decoration: underline;
    text-decoration-color: var(--color-border-medium);
    text-underline-offset: 3px;
    text-decoration-thickness: 2px;
    transition: color var(--duration-fast) var(--easing-ease),
                text-decoration-color var(--duration-fast) var(--easing-ease);
    font-weight: 600;
}

.inline-link:hover {
    color: var(--color-link-hover);
    text-decoration-color: var(--color-link-hover);
}

/* ============================================
   CTA SECTION
   ============================================ */

.cta-section {
    text-align: center;
    background-color: var(--color-bg-accent);
    border: 4px solid var(--color-accent-orange);
    border-radius: var(--radius-md);
}

.cta-section:hover {
    border-color: var(--color-accent-orange);
}

.cta-section .section-title {
    margin-bottom: var(--spacing-xl);
    text-align: left;
}

.cta-box {
    margin-top: var(--spacing-2xl);
}

.cta-button {
    display: inline-block;
    font-family: var(--font-heading);
    font-size: var(--font-size-xl);
    font-weight: 800;
    color: var(--color-bg-secondary);
    background-color: var(--color-accent-orange);
    padding: var(--spacing-lg) var(--spacing-2xl);
    border: 3px solid var(--color-accent-orange);
    border-radius: var(--radius-lg);
    text-decoration: none;
    transition: background-color var(--duration-normal) var(--easing-ease-out),
                border-color var(--duration-normal) var(--easing-ease-out),
                transform var(--duration-fast) var(--easing-ease-out),
                box-shadow var(--duration-normal) var(--easing-ease-out);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    box-shadow: var(--shadow-md);
}

.cta-button:hover {
    background-color: var(--color-accent-orange-dark);
    border-color: var(--color-accent-orange-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.cta-button:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.cta-note {
    margin-top: var(--spacing-xl);
    font-size: var(--font-size-base);
    color: var(--color-text-secondary);
    font-style: italic;
    font-weight: 500;
}

/* ============================================
   FOOTER
   ============================================ */

.site-footer {
    margin-top: var(--spacing-3xl);
    padding-top: var(--spacing-xl);
    border-top: 3px solid var(--color-border-dark);
    text-align: center;
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    font-weight: 500;
}

/* ============================================
   ANIMATIONS
   ============================================ */

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

@media (prefers-reduced-motion: reduce) {
    /* Disable animations */
    .content-section,
    .site-header,
    .status-dot {
        animation: none;
    }
    
    /* Disable hover transforms */
    .cta-button:hover,
    .pricing-card:hover,
    .integration-list li:hover::before,
    .benefits-list li:hover::before,
    .monitoring-list li:hover::before,
    .problems-list li:hover::before,
    .category-list li:hover::before {
        transform: none;
    }
    
    /* Disable transitions */
    .integration-list li::before,
    .benefits-list li::before,
    .monitoring-list li::before,
    .problems-list li::before,
    .category-list li::before {
        transition: none;
    }
}

/* ============================================
   RESPONSIVE ADJUSTMENTS
   ============================================ */

@media (max-width: 767px) {
    .page-wrapper {
        padding: var(--spacing-md) var(--spacing-sm);
    }
    
    .site-header {
        margin-bottom: var(--spacing-2xl);
        padding-bottom: var(--spacing-lg);
    }
    
    .site-title {
        font-size: var(--font-size-2xl);
    }
    
    .status-indicator {
        float: none;
        display: flex;
        margin-left: 0;
        margin-bottom: var(--spacing-sm);
    }
    
    .site-tagline {
        font-size: var(--font-size-base);
    }
    
    .site-subtitle {
        font-size: var(--font-size-sm);
    }
    
    .content-section {
        padding: var(--spacing-md);
        margin-bottom: var(--spacing-lg);
    }
    
    .cta-button {
        font-size: var(--font-size-lg);
        padding: var(--spacing-md) var(--spacing-xl);
    }
    
    .cta-section {
        border-width: 3px;
    }
    
    .pricing-badge {
        font-size: var(--font-size-2xl);
    }
    
    /* Lists revert to single column on mobile */
    .feature-list,
    .integration-list,
    .benefits-list,
    .monitoring-list,
    .problems-list {
        grid-template-columns: 1fr;
    }
    
    /* List items - reduced padding on mobile */
    .feature-list li,
    .integration-list li,
    .benefits-list li,
    .monitoring-list li,
    .problems-list li {
        padding-left: var(--spacing-lg);
    }
    
    /* Smaller checkboxes on mobile */
    .integration-list li::before,
    .benefits-list li::before,
    .monitoring-list li::before,
    .problems-list li::before {
        width: 12px;
        height: 12px;
        top: 0.4em;
        font-size: 9px;
    }
    
    .category-list li::before {
        width: 8px;
        height: 8px;
    }
    
    .use-case-categories {
        grid-template-columns: 1fr;
    }
    
    .steps-list li {
        padding-left: calc(40px + var(--spacing-sm));
    }
    
    .steps-list li::before {
        width: 36px;
        height: 36px;
        font-size: var(--font-size-sm);
    }
}

/* ============================================
   PRINT STYLES
   ============================================ */

@media print {
    .page-wrapper {
        max-width: 100%;
    }
    
    .content-section {
        page-break-inside: avoid;
        box-shadow: none;
        border: 1px solid var(--color-border-dark);
    }
    
    .cta-button {
        border: 2px solid var(--color-text-primary);
        color: var(--color-text-primary);
        background-color: transparent;
    }
}