/* ============================================
   BuildBank V1 — Master Refined
   Vercel-style, clean grid, premium
   ============================================ */

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

:root {
    --bg: #000000;
    --bg-card: #0a0a0a;
    --bg-elevated: #111111;
    --border: #1a1a1a;
    --border-hover: #333333;
    --text: #ededed;
    --text-gray: #888888;
    --text-muted: #555555;
    --accent: #0070f3;
    --font: 'Google Sans Flex', -apple-system, BlinkMacSystemFont, sans-serif;
    --container: 1200px;
    --nav-height: 64px;
    --radius: 8px;
    --transition: 0.2s ease;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

::selection {
    background: var(--accent);
    color: white;
}

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 24px;
}

/* Typography */
h1, h2, h3 {
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
}

.section-headline {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 16px;
}

.section-subhead {
    font-size: 1.125rem;
    color: var(--text-gray);
    max-width: 560px;
}

.section-header {
    margin-bottom: 64px;
}

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

.section-header-center .section-subhead {
    margin: 0 auto;
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    z-index: 1000;
    background: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.nav-container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-weight: 700;
    font-size: 1.125rem;
    color: var(--text);
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 32px;
}

.nav-links a {
    font-size: 0.875rem;
    color: var(--text-gray);
    text-decoration: none;
    transition: color var(--transition);
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    height: 44px;
    padding: 0 24px;
    font-family: var(--font);
    font-size: 0.9375rem;
    font-weight: 600;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: all var(--transition);
    text-decoration: none;
}

.btn-sm {
    height: 38px;
    padding: 0 18px;
    font-size: 0.875rem;
}

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

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

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

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

/* Hero */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0;
    border-bottom: 1px solid var(--border);
}

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

.hero-headline {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.05;
    margin-bottom: 24px;
}

.hero-subhead {
    font-size: 1.125rem;
    color: var(--text-gray);
    max-width: 480px;
    margin-bottom: 32px;
    line-height: 1.7;
}

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

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

.hero-asset {
    width: 100%;
    max-width: 400px;
    height: auto;
}

/* Services Grid - Vercel Style */
.services {
    padding: 120px 0;
    border-bottom: 1px solid var(--border);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1px;
    background: var(--border);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.service-card {
    background: var(--bg);
    padding: 32px;
    display: flex;
    flex-direction: column;
    gap: 16px;
    transition: background var(--transition);
}

.service-card:hover {
    background: var(--bg-card);
}

.card-asset {
    width: 100%;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 8px;
}

.card-asset img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    opacity: 0.8;
}

.card-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    background: var(--bg-elevated);
    border-radius: 12px;
    border: 1px solid var(--border);
}

.service-card h3 {
    font-size: 1rem;
    font-weight: 600;
}

.service-card p {
    font-size: 0.875rem;
    color: var(--text-gray);
    line-height: 1.6;
}

/* Process */
.process {
    padding: 120px 0;
    border-bottom: 1px solid var(--border);
}

.process-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 48px;
}

.process-step {
    text-align: center;
}

.step-marker {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    margin-bottom: 24px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 50%;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    transition: all var(--transition);
}

.step-marker.active {
    border-color: var(--accent);
    color: var(--accent);
    box-shadow: 0 0 24px rgba(0, 112, 243, 0.3);
}

.process-step h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.process-step p {
    font-size: 0.9375rem;
    color: var(--text-gray);
    max-width: 280px;
    margin: 0 auto;
}

/* Final CTA */
.final-cta {
    padding: 160px 0;
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
}

.cta-content {
    text-align: center;
    max-width: 560px;
    margin: 0 auto;
}

.cta-headline {
    font-size: clamp(2rem, 5vw, 3rem);
    margin-bottom: 16px;
}

.cta-subhead {
    font-size: 1.125rem;
    color: var(--text-gray);
    margin-bottom: 40px;
}

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

/* Footer */
.footer {
    padding: 32px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-left {
    display: flex;
    align-items: center;
    gap: 24px;
}

.footer-brand {
    font-weight: 600;
    color: var(--text-gray);
}

.footer-copy {
    font-size: 0.8125rem;
    color: var(--text-muted);
}

.footer-right {
    display: flex;
    gap: 24px;
}

.footer-link {
    font-size: 0.8125rem;
    color: var(--text-muted);
    text-decoration: none;
    transition: color var(--transition);
}

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

/* Responsive */
@media (max-width: 1024px) {
    .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-subhead {
        margin: 0 auto 32px;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .hero-visual {
        order: -1;
    }
    
    .hero-asset {
        max-width: 300px;
    }
    
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    .process-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .cta-buttons .btn {
        width: 100%;
        max-width: 280px;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 16px;
    }
    
    .footer-left {
        flex-direction: column;
        gap: 8px;
    }
}