:root {
    --bg: #0a0a0f;
    --bg-elevated: #12121a;
    --bg-card: #161620;
    --border: rgba(255, 255, 255, 0.08);
    --text: #e8e8ef;
    --text-muted: #9ca3af;
    --accent: #6366f1;
    --accent-light: #818cf8;
    --accent-glow: rgba(99, 102, 241, 0.25);
    --success: #34d399;
    --danger: #f87171;
    --mono: 'JetBrains Mono', monospace;
    --sans: 'Inter', system-ui, sans-serif;
    --radius: 12px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--sans);
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--accent-light);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.nav-content {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--text);
    text-decoration: none;
}

/* Hero */
.hero {
    position: relative;
    min-height: 70vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 8rem 1.5rem 4rem;
    overflow: hidden;
}

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

.hero-gradient {
    position: absolute;
    inset: 0;
    background: radial-gradient(ellipse at 50% 30%, rgba(99, 102, 241, 0.18) 0%, transparent 55%);
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image: linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
                      linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at 50% 0%, black 0%, transparent 70%);
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
}

.eyebrow {
    color: var(--accent-light);
    font-weight: 600;
    font-size: 0.85rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 1rem;
}

.hero h1 {
    font-size: clamp(2.2rem, 6vw, 4rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.25rem;
    background: linear-gradient(135deg, #fff 0%, #a5b4fc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 2.5vw, 1.35rem);
    color: var(--text-muted);
    margin-bottom: 2rem;
    max-width: 640px;
    margin-left: auto;
    margin-right: auto;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.85rem 1.6rem;
    border-radius: 999px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn:hover {
    text-decoration: none;
    transform: translateY(-2px);
}

.btn-primary {
    background: var(--accent);
    color: white;
    box-shadow: 0 4px 24px var(--accent-glow);
}

.btn-primary:hover {
    box-shadow: 0 6px 32px var(--accent-glow);
}

.btn-secondary {
    background: var(--bg-card);
    color: var(--text);
    border: 1px solid var(--border);
}

/* Container */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 1.5rem 4rem;
}

.section {
    margin-bottom: 4rem;
}

.section h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border);
}

.section h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin: 2rem 0 0.75rem;
    color: var(--text);
}

.section p {
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.section strong {
    color: var(--text);
}

/* Intro */
.intro {
    padding: 3rem 0;
    border-bottom: 1px solid var(--border);
    margin-bottom: 3rem;
}

.lead {
    font-size: 1.25rem;
    color: var(--text);
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.meta {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.meta i {
    color: var(--accent-light);
    margin-right: 0.35rem;
}

/* Architecture cards */
.architecture-cards {
    display: grid;
    gap: 1.25rem;
    margin: 2rem 0;
}

.arch-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    position: relative;
    transition: transform 0.2s, border-color 0.2s;
}

.arch-card:hover {
    transform: translateY(-3px);
    border-color: rgba(99, 102, 241, 0.4);
}

.arch-number {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--accent);
    color: white;
    font-weight: 700;
    font-size: 0.85rem;
}

.arch-card h3 {
    margin-top: 0;
    margin-bottom: 0.75rem;
    font-size: 1.15rem;
}

/* Advantages */
.advantage-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.25rem;
    margin-top: 1.5rem;
}

.advantage {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: transform 0.2s, border-color 0.2s;
}

.advantage:hover {
    transform: translateY(-3px);
    border-color: rgba(99, 102, 241, 0.4);
}

.advantage i {
    font-size: 1.5rem;
    color: var(--accent-light);
    margin-bottom: 0.75rem;
}

.advantage h3 {
    margin-top: 0;
    margin-bottom: 0.5rem;
    font-size: 1.05rem;
}

.advantage p {
    margin-bottom: 0;
    font-size: 0.95rem;
}

/* Cost table */
.cost-table {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    margin-top: 1.5rem;
}

.cost-row {
    display: grid;
    grid-template-columns: 120px 1fr 1fr;
    gap: 1rem;
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--border);
    font-size: 0.92rem;
}

.cost-row:last-child {
    border-bottom: none;
}

.cost-header {
    background: var(--bg-elevated);
    font-weight: 600;
    color: var(--text);
}

.cost-row span:first-child {
    color: var(--accent-light);
    font-weight: 500;
}

.cost-row span {
    color: var(--text-muted);
}

/* Code blocks */
.code-block {
    background: #0d0d14;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.25rem;
    font-family: var(--mono);
    font-size: 0.85rem;
    line-height: 1.6;
    overflow-x: auto;
    margin: 1rem 0 1.5rem;
    color: #d4d4d8;
    white-space: pre;
}

.code-block .comment {
    color: #6b7280;
}

.section code {
    font-family: var(--mono);
    background: var(--bg-elevated);
    padding: 0.15rem 0.4rem;
    border-radius: 4px;
    font-size: 0.85em;
    color: var(--accent-light);
}

/* Do's and don'ts */
.dosdonts {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.dos, .donts {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
}

.dos h3 {
    color: var(--success);
    margin-top: 0;
}

.donts h3 {
    color: var(--danger);
    margin-top: 0;
}

.dosdonts ul {
    list-style: none;
}

.dosdonts li {
    margin-bottom: 0.85rem;
    color: var(--text-muted);
    font-size: 0.95rem;
    padding-left: 1.25rem;
    position: relative;
}

.dosdonts li::before {
    position: absolute;
    left: 0;
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
}

.dos li::before {
    content: '\f00c';
    color: var(--success);
}

.donts li::before {
    content: '\f00d';
    color: var(--danger);
}

.dosdonts strong {
    color: var(--text);
}

/* CTA */
.cta {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 3rem 2rem;
    text-align: center;
    margin-top: 2rem;
}

.cta h2 {
    border-bottom: none;
    margin-bottom: 0.75rem;
}

.cta p {
    max-width: 560px;
    margin: 0 auto 1.5rem;
}

/* Footer */
.footer {
    text-align: center;
    padding: 2rem 1.5rem;
    border-top: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .hero {
        min-height: 60vh;
        padding-top: 6rem;
    }

    .architecture-cards,
    .advantage-grid,
    .dosdonts {
        grid-template-columns: 1fr;
    }

    .cost-row {
        grid-template-columns: 1fr;
        gap: 0.35rem;
    }

    .cost-header {
        display: none;
    }

    .cost-row span:first-child {
        font-weight: 700;
    }
}