:root {
    --bg: #0a0e17;
    --bg-alt: #111827;
    --surface: #1a2332;
    --border: #2a3548;
    --text: #e2e8f0;
    --text-muted: #94a3b8;
    --accent: #38bdf8;
    --accent-hover: #7dd3fc;
    --accent-glow: rgba(56, 189, 248, 0.15);
    --green: #4ade80;
    --yellow: #facc15;
    --red: #f87171;
    --radius: 12px;
    --radius-sm: 8px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1140px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ── Navbar ── */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(10, 14, 23, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text);
    text-decoration: none;
}

.logo-icon {
    width: 24px;
    height: 24px;
    color: var(--accent);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: transform 0.2s;
}

/* ── Hero ── */

.hero {
    padding: 140px 0 80px;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 48px;
    align-items: center;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.12;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--text) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    margin-top: 20px;
    font-size: 1.15rem;
    color: var(--text-muted);
    max-width: 480px;
    line-height: 1.7;
}

.hero-actions {
    margin-top: 32px;
    display: flex;
    gap: 16px;
}

.btn {
    display: inline-flex;
    align-items: center;
    padding: 12px 28px;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background: var(--accent-hover);
    box-shadow: 0 0 24px var(--accent-glow);
}

.btn-outline {
    background: transparent;
    color: var(--accent);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    border-color: var(--accent);
    background: var(--accent-glow);
}

.hero-screenshot {
    width: 100%;
    height: auto;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    object-fit: contain;
}

/* ── Sections ── */

.section {
    padding: 100px 0;
}

.section-alt {
    background: var(--bg-alt);
}

.section-title {
    font-size: 2.2rem;
    font-weight: 800;
    text-align: center;
    letter-spacing: -0.02em;
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    margin-top: 12px;
    max-width: 560px;
    margin-left: auto;
    margin-right: auto;
    font-size: 1.05rem;
}

.subsection-title {
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    margin-top: 64px;
    margin-bottom: 0;
}

/* ── Features ── */

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 56px;
}

.feature-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
    border-color: var(--accent);
    box-shadow: 0 0 30px var(--accent-glow);
}

.feature-icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--accent-glow);
    border-radius: var(--radius-sm);
    margin-bottom: 18px;
}

.feature-icon svg {
    width: 22px;
    height: 22px;
    color: var(--accent);
}

.feature-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.feature-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.6;
}

/* ── Screenshots ── */

.screenshot-showcase {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-top: 40px;
}

.showcase-item {
    position: relative;
    border-radius: var(--radius);
    overflow: hidden;
    border: 1px solid var(--border);
    background: #0d1117;
    transition: border-color 0.3s, box-shadow 0.3s;
    display: flex;
    flex-direction: column;
}

.showcase-item:hover {
    border-color: var(--accent);
    box-shadow: 0 8px 40px rgba(56, 189, 248, 0.1);
}

.showcase-full {
    grid-column: 1 / -1;
}

.showcase-label {
    background: rgba(10, 14, 23, 0.9);
    color: var(--accent);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 10px 16px;
    border-bottom: 1px solid var(--border);
}

.showcase-item img {
    width: 100%;
    height: auto;
    display: block;
    padding: 8px;
}

.showcase-item:not(.showcase-full) img {
    aspect-ratio: 2.2 / 1;
    object-fit: contain;
}

/* ── Architecture ── */

.arch-diagram {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-top: 56px;
    flex-wrap: wrap;
}

.arch-node {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
    text-align: center;
    max-width: 220px;
    flex: 0 0 auto;
    transition: border-color 0.2s;
}

.arch-node:hover {
    border-color: var(--accent);
}

.arch-highlight {
    border-color: var(--accent);
    box-shadow: 0 0 30px var(--accent-glow);
}

.arch-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--accent-glow);
    border-radius: 50%;
}

.arch-icon svg {
    width: 24px;
    height: 24px;
    color: var(--accent);
}

.arch-node h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 6px;
}

.arch-node p {
    font-size: 0.8rem;
    color: var(--text-muted);
    line-height: 1.5;
}

.arch-arrow {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    color: var(--text-muted);
}

.arch-arrow svg {
    width: 60px;
    height: 24px;
}

.arch-arrow span {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

/* ── How It Works ── */

.steps {
    margin-top: 56px;
    display: flex;
    flex-direction: column;
    gap: 0;
    position: relative;
    max-width: 680px;
    margin-left: auto;
    margin-right: auto;
}

.steps::before {
    content: "";
    position: absolute;
    left: 28px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border);
}

.step {
    display: flex;
    gap: 24px;
    padding: 32px 0;
    position: relative;
}

.step-number {
    flex-shrink: 0;
    width: 56px;
    height: 56px;
    background: var(--surface);
    border: 2px solid var(--accent);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 800;
    color: var(--accent);
    position: relative;
    z-index: 1;
}

.step-content h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.step-content p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* ── What You See ── */

.data-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 56px;
}

.data-category {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
}

.data-category h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.data-icon {
    width: 20px;
    height: 20px;
    color: var(--accent);
    flex-shrink: 0;
}

.data-category ul {
    list-style: none;
}

.data-category li {
    padding: 6px 0;
    font-size: 0.85rem;
    color: var(--text-muted);
    position: relative;
    padding-left: 14px;
}

.data-category li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    width: 5px;
    height: 5px;
    background: var(--accent);
    border-radius: 50%;
    transform: translateY(-50%);
}

/* ── Getting Started ── */

.requirements {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-top: 56px;
}

.req-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
}

.req-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 18px;
}

.checklist {
    list-style: none;
}

.checklist li {
    padding: 8px 0;
    font-size: 0.9rem;
    color: var(--text-muted);
    padding-left: 28px;
    position: relative;
}

.checklist li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 18px;
    height: 18px;
    border: 2px solid var(--green);
    border-radius: 4px;
    background: rgba(74, 222, 128, 0.1);
}

.checklist li::after {
    content: "";
    position: absolute;
    left: 4px;
    top: 50%;
    transform: translateY(-50%) rotate(45deg);
    width: 5px;
    height: 9px;
    border-right: 2px solid var(--green);
    border-bottom: 2px solid var(--green);
}

.setup-steps {
    margin-top: 40px;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.setup-step {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    transition: border-color 0.2s;
}

.setup-step:hover {
    border-color: var(--accent);
}

.setup-num {
    display: block;
    font-size: 2rem;
    font-weight: 800;
    color: var(--accent);
    opacity: 0.4;
    margin-bottom: 12px;
}

.setup-step h4 {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 6px;
}

.setup-step p {
    font-size: 0.85rem;
    color: var(--text-muted);
    line-height: 1.6;
}

/* ── CTA ── */

.cta-section {
    text-align: center;
}

.cta-section h2 {
    font-size: 2rem;
    font-weight: 800;
}

.cta-section p {
    color: var(--text-muted);
    margin-top: 12px;
    font-size: 1.05rem;
}

/* ── Footer ── */

.footer {
    padding: 32px 0;
    border-top: 1px solid var(--border);
    text-align: center;
}

.footer p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ── Responsive ── */

@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .data-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .setup-steps {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--bg);
        border-bottom: 1px solid var(--border);
        padding: 16px 24px;
        gap: 16px;
    }

    .nav-links.open {
        display: flex;
    }

    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero {
        padding: 100px 0 60px;
        min-height: auto;
    }

    .hero h1 {
        font-size: 2.2rem;
    }

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

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

    .screenshot-showcase {
        grid-template-columns: 1fr;
    }

    .arch-diagram {
        flex-direction: column;
    }

    .arch-arrow {
        transform: rotate(90deg);
    }

    .arch-node {
        max-width: 100%;
        width: 100%;
    }

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

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

    .setup-steps {
        grid-template-columns: 1fr;
    }

    .section {
        padding: 64px 0;
    }

    .section-title {
        font-size: 1.7rem;
    }
}

/* ── Scroll animations ── */

.feature-card,
.arch-node,
.step,
.data-category,
.req-card,
.setup-step,
.showcase-item {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.feature-card.visible,
.arch-node.visible,
.step.visible,
.data-category.visible,
.req-card.visible,
.setup-step.visible,
.showcase-item.visible {
    opacity: 1;
    transform: translateY(0);
}