/* ================================================
   LAYOUT — Nav, Footer, Grid, Responsive
   ================================================ */

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-nav);
    padding: var(--space-md) var(--space-lg);
    transition: background var(--transition-base),
                padding var(--transition-base),
                box-shadow var(--transition-base);
}

.nav.scrolled {
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 0 var(--divider);
    padding: var(--space-sm) var(--space-lg);
}

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

.nav-brand {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
    text-decoration: none;
    flex-shrink: 0;
}

.nav-logo-text {
    font-family: var(--font-display);
    font-size: 1.4rem;
    font-weight: 500;
    color: var(--nav-text);
    letter-spacing: 0.02em;
    transition: color var(--transition-base);
    white-space: nowrap;
}

.nav.at-top .nav-logo-text {
    color: #fff;
}

.nav-subtitle {
    font-family: var(--font-body);
    font-size: 0.65rem;
    font-weight: 400;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    transition: color var(--transition-base);
}

.nav.at-top .nav-subtitle {
    color: rgba(255, 255, 255, 0.7);
}

.nav-links {
    display: flex;
    gap: 2.5rem;
    align-items: center;
}

.nav-link {
    font-size: 0.8rem;
    font-weight: 400;
    color: var(--nav-text);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    transition: color var(--transition-fast);
    position: relative;
}

.nav.at-top .nav-link {
    color: #fff;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--accent);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* Mobile menu button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 0.5rem;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 1.5px;
    background: var(--nav-text);
    transition: var(--transition-base);
}

.nav.at-top .mobile-menu-btn span {
    background: #fff;
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}
.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}
.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile nav overlay */
.mobile-nav {
    display: none;
    position: fixed;
    inset: 0;
    background: var(--bg-primary);
    z-index: calc(var(--z-nav) - 1);
    padding-top: 5rem;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2rem;
    opacity: 0;
    transition: opacity var(--transition-base);
}

.mobile-nav.open {
    display: flex;
    opacity: 1;
}

.mobile-nav a {
    font-family: var(--font-display);
    font-size: 2rem;
    color: var(--text-primary);
    transition: color var(--transition-fast);
}

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

/* Footer */
.footer {
    padding: var(--space-lg);
    background: var(--bg-secondary);
    border-top: 1px solid var(--divider);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
}

.footer-brand {
    font-family: var(--font-display);
    font-size: 1.5rem;
    color: var(--text-primary);
    font-weight: 500;
}

.footer-socials {
    display: flex;
    gap: var(--space-md);
}

.footer-social-link {
    font-size: 0.8rem;
    font-weight: 400;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    transition: color var(--transition-fast);
}

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

.footer-copy {
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-align: center;
}

/* Mobile CTA Bar */
.mobile-cta {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    padding: var(--space-sm) var(--space-md);
    box-shadow: 0 -4px 20px var(--card-shadow);
    z-index: var(--z-nav);
}

.mobile-cta-buttons {
    display: flex;
    gap: 0.75rem;
}

.mobile-cta .btn {
    flex: 1;
    text-align: center;
}

/* Responsive */
@media (max-width: 1024px) {
    .nav {
        padding: var(--space-sm) var(--space-md);
    }
    .nav.scrolled {
        padding: 0.75rem var(--space-md);
    }
    .section {
        padding-left: var(--space-md);
        padding-right: var(--space-md);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    .mobile-menu-btn {
        display: flex;
    }
    .section {
        padding-top: var(--space-xl);
        padding-bottom: var(--space-xl);
    }
    .mobile-cta {
        display: block;
    }
    .footer {
        padding-bottom: 5rem;
    }
}