/* ===== CSS Variables ===== */
:root {
    --color-black: #000000;
    --color-white: #ffffff;
    --color-gray-100: #f5f5f5;
    --color-gray-200: #e5e5e5;
    --color-gray-300: #d4d4d4;
    --color-gray-400: #a3a3a3;
    --color-gray-500: #737373;
    --color-gray-600: #525252;
    --color-gray-700: #404040;
    --color-gray-800: #262626;
    --color-gray-900: #171717;
    
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    
    --container-max: 1200px;
    --container-padding: 24px;
    
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* ===== Reset & Base ===== */
*, *::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(--color-black);
    color: var(--color-white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
    list-style: none;
}

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

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

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(2.5rem, 6vw, 5rem);
}

h2 {
    font-size: clamp(2rem, 4vw, 3.5rem);
}

h3 {
    font-size: clamp(1.25rem, 2vw, 1.75rem);
}

h4 {
    font-size: 1.125rem;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 28px;
    font-size: 0.875rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    border-radius: 6px;
    transition: all var(--transition-normal);
    cursor: pointer;
}

.btn-primary {
    background-color: var(--color-white);
    color: var(--color-black);
    border: 1px solid var(--color-white);
}

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

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

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

.btn-full {
    width: 100%;
}

/* ===== Section Tag ===== */
.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-gray-400);
    margin-bottom: 16px;
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 64px;
}

.section-header p {
    margin-top: 20px;
    color: var(--color-gray-400);
    font-size: 1.125rem;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 20px 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: all var(--transition-normal);
}

.navbar.scrolled {
    padding: 16px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-img {
    height: 32px;
    width: auto;
    filter: invert(1);
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--color-white);
}

.nav-links {
    display: flex;
    gap: 40px;
}

.nav-links a {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-gray-300);
    transition: color var(--transition-fast);
}

.nav-links a:hover {
    color: var(--color-white);
}

.nav-cta {
    font-size: 0.875rem;
    font-weight: 500;
    padding: 10px 20px;
    border: 1px solid var(--color-gray-600);
    border-radius: 6px;
    transition: all var(--transition-fast);
}

.nav-cta:hover {
    border-color: var(--color-white);
    background-color: var(--color-white);
    color: var(--color-black);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 5px;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-white);
    transition: all var(--transition-fast);
}

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

.hero-video-container {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(100%);
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(
        to bottom,
        rgba(0, 0, 0, 0.7) 0%,
        rgba(0, 0, 0, 0.5) 50%,
        rgba(0, 0, 0, 0.9) 100%
    );
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
    padding-top: 80px;
    text-align: center;
}

.hero-eyebrow {
    font-size: 0.875rem;
    font-weight: 500;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-gray-400);
    margin-bottom: 24px;
}

.hero h1 {
    margin-bottom: 24px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-gray-300);
    max-width: 600px;
    margin: 0 auto 40px;
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
}

.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
}

.scroll-indicator span {
    display: block;
    width: 24px;
    height: 40px;
    border: 2px solid var(--color-gray-500);
    border-radius: 12px;
    position: relative;
}

.scroll-indicator span::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 8px;
    background-color: var(--color-white);
    border-radius: 2px;
    animation: scroll 2s infinite;
}

@keyframes scroll {
    0%, 100% {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
    50% {
        opacity: 0.5;
        transform: translateX(-50%) translateY(10px);
    }
}

/* ===== Manifesto Section ===== */
.manifesto {
    padding: 120px 0;
    background-color: var(--color-black);
    border-bottom: 1px solid var(--color-gray-800);
}

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

.manifesto-text {
    font-size: clamp(1.5rem, 3vw, 2.25rem);
    line-height: 1.6;
    color: var(--color-gray-400);
    font-weight: 300;
}

.manifesto-text .highlight {
    color: var(--color-white);
    font-weight: 500;
}

/* ===== Capabilities Section ===== */
.capabilities {
    padding: 100px 0 0;
    background-color: var(--color-black);
}

.capabilities-header {
    text-align: center;
    margin-bottom: 60px;
}

.capabilities-header h2 {
    font-size: clamp(1.75rem, 3vw, 2.5rem);
}

.capabilities-showcase {
    display: flex;
    overflow-x: auto;
    gap: 2px;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}

.capabilities-showcase::-webkit-scrollbar {
    display: none;
}

.showcase-item {
    flex: 0 0 auto;
    width: 33.333vw;
    min-width: 300px;
    max-width: 500px;
    scroll-snap-align: start;
    position: relative;
    overflow: hidden;
}

.showcase-video {
    aspect-ratio: 3/4;
    overflow: hidden;
}

.showcase-video video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(100%);
    transition: all var(--transition-slow);
}

.showcase-item:hover .showcase-video video {
    filter: grayscale(0%);
    transform: scale(1.05);
}

.showcase-label {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 60px 24px 24px;
    background: linear-gradient(to top, rgba(0,0,0,0.95) 0%, transparent 100%);
}

.showcase-label h3 {
    font-size: 1.25rem;
    margin-bottom: 4px;
}

.showcase-label p {
    font-size: 0.875rem;
    color: var(--color-gray-400);
    line-height: 1.5;
}

/* ===== How It Works Section ===== */
.how-it-works {
    padding: 120px 0;
    background-color: var(--color-gray-900);
}

.how-it-works h2 {
    text-align: center;
    margin-bottom: 80px;
    font-size: clamp(1.75rem, 3vw, 2.5rem);
}

.timeline {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 20px;
    left: calc(12.5% + 12px);
    right: calc(12.5% + 12px);
    height: 1px;
    background: var(--color-gray-700);
}

.timeline-item {
    text-align: center;
}

.timeline-marker {
    width: 40px;
    height: 40px;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-white);
    color: var(--color-black);
    border-radius: 50%;
    font-weight: 700;
    font-size: 0.875rem;
    position: relative;
    z-index: 1;
}

.timeline-content h3 {
    font-size: 1.125rem;
    margin-bottom: 8px;
}

.timeline-content p {
    font-size: 0.875rem;
    color: var(--color-gray-400);
    line-height: 1.6;
}

/* Legacy tech styles for reference */
.tech-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.tech-content h2 {
    margin-bottom: 24px;
}

.tech-content > p {
    color: var(--color-gray-400);
    font-size: 1.125rem;
    margin-bottom: 48px;
}

.tech-steps {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.tech-step {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.step-number {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-gray-800);
    border: 1px solid var(--color-gray-700);
    border-radius: 8px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--color-gray-400);
}

.step-content h4 {
    margin-bottom: 4px;
}

.step-content p {
    color: var(--color-gray-500);
    font-size: 0.875rem;
}

.tech-visual {
    display: flex;
    align-items: center;
    justify-content: center;
}

.tech-diagram {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    position: relative;
}

.diagram-circle {
    width: 120px;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    border: 2px solid var(--color-gray-700);
    font-weight: 600;
    font-size: 0.875rem;
    position: relative;
}

.diagram-ai {
    background-color: var(--color-white);
    color: var(--color-black);
    border-color: var(--color-white);
}

.diagram-safety {
    background-color: var(--color-gray-800);
}

.diagram-human {
    background-color: transparent;
}

.diagram-arrow {
    width: 2px;
    height: 30px;
    background: linear-gradient(to bottom, var(--color-gray-600), var(--color-gray-700));
    position: relative;
}

.diagram-arrow::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 6px solid var(--color-gray-700);
}

.diagram-feedback {
    position: absolute;
    right: -60px;
    top: 60px;
    bottom: 60px;
    width: 40px;
    border: 2px solid var(--color-gray-700);
    border-left: none;
    border-radius: 0 20px 20px 0;
}

.diagram-feedback::after {
    content: '';
    position: absolute;
    top: -2px;
    left: -3px;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-bottom: 6px solid var(--color-gray-700);
}

/* ===== Value Props Section ===== */
.value-props {
    padding: 120px 0;
    background-color: var(--color-black);
}

.value-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.value-card {
    padding: 40px;
    background-color: var(--color-gray-900);
    border: 1px solid var(--color-gray-800);
    border-radius: 16px;
    text-align: center;
    transition: all var(--transition-normal);
}

.value-card:hover {
    border-color: var(--color-gray-600);
    transform: translateY(-4px);
}

.value-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-white);
    border-radius: 12px;
}

.value-icon svg {
    width: 28px;
    height: 28px;
    stroke: var(--color-black);
}

.value-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
}

.value-card p {
    font-size: 0.9375rem;
    color: var(--color-gray-400);
    line-height: 1.7;
}

/* ===== FAQ Section ===== */
.faq {
    padding: 120px 0;
    background-color: var(--color-gray-900);
}

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

.faq-item {
    border-bottom: 1px solid var(--color-gray-800);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 24px 0;
    font-size: 1rem;
    font-weight: 500;
    text-align: left;
    color: var(--color-white);
    transition: color var(--transition-fast);
}

.faq-question:hover {
    color: var(--color-gray-300);
}

.faq-question svg {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    color: var(--color-gray-500);
    transition: transform var(--transition-normal);
}

.faq-item.active .faq-question svg {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal), padding var(--transition-normal);
}

.faq-item.active .faq-answer {
    max-height: 300px;
}

.faq-answer p {
    padding-bottom: 24px;
    color: var(--color-gray-400);
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* ===== Contact Section ===== */
.contact {
    padding: 120px 0;
    background-color: var(--color-black);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: start;
}

.contact-content h2 {
    margin-bottom: 20px;
}

.contact-content > p {
    color: var(--color-gray-400);
    font-size: 1.125rem;
    margin-bottom: 32px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: var(--color-gray-300);
    font-size: 0.9375rem;
    transition: color var(--transition-fast);
}

.contact-link:hover {
    color: var(--color-white);
}

.contact-link svg {
    width: 20px;
    height: 20px;
}

.contact-form-wrapper {
    background-color: var(--color-gray-900);
    border: 1px solid var(--color-gray-800);
    border-radius: 12px;
    padding: 48px;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-gray-300);
}

.form-group input,
.form-group textarea {
    padding: 14px 16px;
    font-family: inherit;
    font-size: 0.9375rem;
    background-color: var(--color-gray-800);
    border: 1px solid var(--color-gray-700);
    border-radius: 8px;
    color: var(--color-white);
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-gray-500);
    background-color: var(--color-gray-900);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

/* ===== Footer ===== */
.footer {
    padding: 80px 0 40px;
    background-color: var(--color-gray-900);
    border-top: 1px solid var(--color-gray-800);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: 80px;
    margin-bottom: 60px;
}

.footer-brand {
    max-width: 300px;
}

.footer-logo {
    height: 28px;
    width: auto;
    filter: invert(1);
    margin-bottom: 16px;
}

.footer-brand p {
    color: var(--color-gray-500);
    font-size: 0.875rem;
}

.footer-links {
    display: flex;
    gap: 80px;
}

.footer-col h4 {
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--color-white);
}

.footer-col ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-col a {
    font-size: 0.875rem;
    color: var(--color-gray-500);
    transition: color var(--transition-fast);
}

.footer-col a:hover {
    color: var(--color-white);
}

.footer-bottom {
    padding-top: 40px;
    border-top: 1px solid var(--color-gray-800);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.8125rem;
    color: var(--color-gray-600);
}

/* ===== Responsive Design ===== */
@media (max-width: 1024px) {
    .tech-grid,
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 60px;
    }
    
    .tech-visual {
        order: -1;
    }
    
    .value-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .timeline {
        grid-template-columns: repeat(2, 1fr);
        gap: 40px;
    }
    
    .timeline::before {
        display: none;
    }
}

@media (max-width: 768px) {
    .nav-links,
    .nav-cta {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .timeline {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    
    .showcase-item {
        width: 80vw;
        min-width: 280px;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-cta .btn {
        width: 100%;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 48px;
    }
    
    .footer-links {
        gap: 48px;
    }
    
    .contact-form-wrapper {
        padding: 32px;
    }
    
    .value-card {
        padding: 32px;
    }
    
    .manifesto-text {
        font-size: 1.25rem;
    }
}

@media (max-width: 480px) {
    :root {
        --container-padding: 16px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 32px;
    }
    
    .diagram-feedback {
        display: none;
    }
}

/* ===== Mobile Menu ===== */
.nav-links.mobile-active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-black);
    border-bottom: 1px solid var(--color-gray-800);
    padding: 24px;
    gap: 20px;
}

.nav-links.mobile-active a {
    font-size: 1rem;
}

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

.animate-in {
    animation: fadeInUp 0.6s ease forwards;
    opacity: 0;
}

.animate-delay-1 { animation-delay: 0.1s; }
.animate-delay-2 { animation-delay: 0.2s; }
.animate-delay-3 { animation-delay: 0.3s; }
.animate-delay-4 { animation-delay: 0.4s; }

/* ===== Utility Classes ===== */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}