:root {
    --primary: #0a1628;
    --primary-blue: #1e3a5f;
    --accent: #0077ff;
    --accent-light: #339dff;
    --accent-glow: 0 0 20px rgba(0, 119, 255, 0.25);
    --accent-glow-strong: 0 0 30px rgba(0, 119, 255, 0.35);
    --bg-white: #f8fafc;
    --bg-card: rgba(255, 255, 255, 0.88);
    --text-body: #4a5d73;
    --text-heading: #0f1d2e;
    --text-dim: rgba(74, 93, 115, 0.5);
    --border-light: rgba(0, 119, 255, 0.1);
    --border-accent: rgba(0, 119, 255, 0.25);
    --shadow-soft: 0 8px 32px rgba(10, 22, 40, 0.06);
    --shadow-card: 0 4px 24px rgba(10, 22, 40, 0.05);
}

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

html {
    scroll-behavior: smooth;
}

body {
    background: var(--bg-white);
    color: var(--text-body);
    font-family: -apple-system, BlinkMacSystemFont, 'Inter', 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

#robot-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    pointer-events: none;
}

.ambient-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
    background: 
        radial-gradient(ellipse at 20% 80%, rgba(0, 119, 255, 0.05) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(0, 180, 255, 0.04) 0%, transparent 50%);
}

.noise {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0.012;
    pointer-events: none;
    z-index: 2;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
}

.content {
    position: relative;
    z-index: 10;
}

/* Navigation */
nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 24px 5%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
    background: linear-gradient(to bottom, rgba(248, 250, 252, 0.95) 0%, rgba(248, 250, 252, 0) 100%);
}

.logo {
    text-decoration: none;
    display: flex;
    flex-direction: column;
    gap: 0;
}

.logo-main {
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.5px;
    line-height: 1;
}

.logo-sim {
    color: var(--accent);
}

.logo-robot {
    color: var(--text-heading);
}

.logo-tagline {
    font-size: 11px;
    color: var(--text-heading);
    letter-spacing: 0.3px;
    font-weight: 400;
    margin-top: -1px;
}

.nav-cta {
    background: transparent;
    border: 1px solid var(--border-accent);
    color: var(--accent);
    padding: 10px 24px;
    font-family: inherit;
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.25s ease;
}

.nav-cta:hover {
    background: var(--accent);
    border-color: var(--accent);
    color: white;
    box-shadow: var(--accent-glow);
}

/* Hero */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 0 5%;
}

.hero-box {
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    padding: 3rem 3.5rem;
    max-width: 600px;
    box-shadow: var(--shadow-card);
    backdrop-filter: blur(16px);
    border-radius: 16px;
}

.hero-box h1 {
    font-size: clamp(26px, 4vw, 42px);
    font-weight: 600;
    color: var(--text-heading);
    margin-bottom: 1rem;
    letter-spacing: -0.6px;
    line-height: 1.15;
    white-space: nowrap;
}

.hero-tagline {
    font-size: clamp(18px, 2.2vw, 22px);
    line-height: 1.5;
    color: var(--accent);
    font-weight: 500;
    margin-bottom: 1.2rem;
}

.hero-body {
    font-size: 15px;
    line-height: 1.75;
    color: var(--text-body);
}

/* Card sections */
.card-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 4rem 5%;
}

.card-section:nth-child(odd) {
    justify-content: flex-start;
}

.card-section:nth-child(even) {
    justify-content: flex-end;
}

.card-group {
    display: flex;
    flex-direction: column;
    gap: 20px;
    max-width: 540px;
}

.text-box {
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    padding: 2.2rem 2.8rem;
    box-shadow: var(--shadow-card);
    backdrop-filter: blur(16px);
    border-radius: 16px;
    opacity: 0;
    transform: translateY(24px);
    transition: all 0.5s cubic-bezier(0.23, 1, 0.32, 1);
}

.text-box.visible {
    opacity: 1;
    transform: translateY(0);
}

.text-box h2 {
    color: var(--accent);
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 0.9rem;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.text-box p {
    font-size: 15px;
    line-height: 1.75;
    color: var(--text-body);
}

/* Video placeholder */
.video-placeholder {
    background: rgba(0, 119, 255, 0.02);
    border: 1px solid var(--border-light);
    border-radius: 16px;
    aspect-ratio: 16 / 9;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 12px;
    opacity: 0;
    transform: translateY(24px);
    transition: all 0.5s cubic-bezier(0.23, 1, 0.32, 1) 0.1s;
    cursor: pointer;
}

.video-placeholder.visible {
    opacity: 1;
    transform: translateY(0);
}

.video-placeholder:hover {
    border-color: var(--border-accent);
    background: rgba(0, 119, 255, 0.04);
    box-shadow: var(--accent-glow);
}

.play-icon {
    width: 60px;
    height: 60px;
    border: 1.5px solid var(--accent);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent);
    font-size: 18px;
    transition: all 0.25s ease;
}

.video-placeholder:hover .play-icon {
    background: var(--accent);
    color: white;
    transform: scale(1.05);
    box-shadow: var(--accent-glow);
}

.video-label {
    font-size: 12px;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 500;
}

/* CTA */
.cta-section {
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 5%;
}

.cta-box {
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    padding: 3rem 4rem;
    text-align: center;
    max-width: 480px;
    box-shadow: var(--shadow-card);
    backdrop-filter: blur(16px);
    border-radius: 16px;
}

.cta-box h2 {
    font-size: clamp(22px, 2.5vw, 28px);
    font-weight: 600;
    color: var(--text-heading);
    margin-bottom: 0.9rem;
    letter-spacing: -0.3px;
}

.cta-box p {
    font-size: 15px;
    margin-bottom: 1.8rem;
    color: var(--text-body);
}

.btn-primary {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 14px 32px;
    font-family: inherit;
    font-size: 15px;
    font-weight: 500;
    text-decoration: none;
    border-radius: 10px;
    transition: all 0.25s ease;
    box-shadow: var(--accent-glow);
}

.btn-primary:hover {
    background: var(--accent-light);
    transform: translateY(-2px);
    box-shadow: var(--accent-glow-strong);
}

/* Footer */
footer {
    padding: 32px 5%;
    text-align: center;
    border-top: 1px solid var(--border-light);
}

.footer-text {
    font-size: 13px;
    color: var(--text-dim);
    letter-spacing: 0.3px;
}

/* IREX Badge */
.irex-badge {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    padding: 12px 20px;
    backdrop-filter: blur(16px);
    z-index: 100;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    box-shadow: var(--shadow-soft);
    border-radius: 12px;
}

.irex-badge strong {
    color: var(--accent);
    font-weight: 600;
}

/* Progress bar */
.progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent), var(--accent-light));
    z-index: 200;
    width: 0%;
    box-shadow: var(--accent-glow);
}

/* Scroll indicator */
.scroll-indicator {
    position: fixed;
    bottom: 28px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--accent);
    font-size: 11px;
    z-index: 100;
    animation: pulse 2s infinite;
    letter-spacing: 2px;
    font-weight: 500;
    text-shadow: 0 0 12px rgba(0, 119, 255, 0.3);
}

@keyframes pulse {
    0%, 100% { opacity: 0.35; }
    50% { opacity: 0.85; }
}

/* Responsive */
@media (max-width: 768px) {
    .hero-box, .text-box, .cta-box {
        padding: 1.8rem 2rem;
    }
    
    .card-group {
        max-width: 100%;
    }
    
    .card-section:nth-child(odd),
    .card-section:nth-child(even) {
        justify-content: center;
    }
    
    .irex-badge {
        bottom: 16px;
        right: 16px;
        left: 16px;
        justify-content: center;
    }
    
    .scroll-indicator {
        display: none;
    }
}