/**
 * ByteStream Layout Systems & Global Shell
 * Phase 3 & 16: Navigation & Footer Architecture
 */

/* Container & Sections */
.container {
    width: 100%;
    max-width: var(--container-max-width);
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--container-padding);
    padding-right: var(--container-padding);
}

.container-narrow {
    max-width: 960px;
}

.container-wide {
    max-width: 1400px;
}

.section-padding {
    padding-top: clamp(64px, 8vw, 112px);
    padding-bottom: clamp(64px, 8vw, 112px);
}

.section-padding-sm {
    padding-top: clamp(40px, 5vw, 64px);
    padding-bottom: clamp(40px, 5vw, 64px);
}

.bg-light {
    background-color: var(--color-light-gray);
}

.bg-navy {
    background-color: var(--color-primary-navy);
    color: var(--color-white);
}

.bg-white {
    background-color: var(--color-white);
}

/* ==========================================================================
   ENTERPRISE HEADER & NAVIGATION (Phase 3)
   ========================================================================== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1200;
    transition: background-color var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.site-header.is-menu-open {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
    background-color: var(--color-white) !important;
}

.site-header.is-scrolled {
    background-color: rgba(255, 255, 255, 0.98);
    box-shadow: 0 4px 20px rgba(17, 24, 39, 0.04);
    border-bottom-color: rgba(55, 65, 81, 0.06);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

/* Brand Logo (Zero Hover Effect) */
.brand-logo {
    display: inline-flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--color-primary-navy) !important;
    letter-spacing: -0.035em;
    text-decoration: none !important;
    user-select: none;
    line-height: 1;
    transition: none !important;
    transform: none !important;
    opacity: 1 !important;
    cursor: pointer;
}

.brand-logo:hover,
.brand-logo:focus,
.brand-logo:active,
.brand-logo:visited {
    color: var(--color-primary-navy) !important;
    text-decoration: none !important;
    transform: none !important;
    opacity: 1 !important;
}

.brand-logo .brand-stream {
    color: var(--color-primary-blue) !important;
    transition: none !important;
}

.brand-logo:hover .brand-stream,
.brand-logo:focus .brand-stream,
.brand-logo:active .brand-stream,
.brand-logo:visited .brand-stream {
    color: var(--color-primary-blue) !important;
}

/* Desktop Navigation Menu */
.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--space-8);
    height: 100%;
    margin: 0;
    padding: 0;
}

.nav-item {
    position: relative;
    height: 100%;
    display: flex;
    align-items: center;
}

.nav-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--color-dark-gray);
    padding: var(--space-2) 0;
    position: relative;
    transition: color var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-primary-blue);
}

.nav-link .nav-chevron {
    font-size: 10px;
    transition: transform var(--transition-base);
}

.nav-item:hover .nav-link .nav-chevron {
    transform: rotate(180deg);
}

/* ==========================================================================
   DESKTOP MEGA MENU ARCHITECTURE (Min-width: 1025px)
   ========================================================================== */
@media (min-width: 1025px) {
    .nav-item.has-mega-menu {
        position: relative;
    }

    .mega-menu-wrapper {
        position: absolute;
        top: 100%;
        left: -120px;
        width: 820px;
        background-color: var(--color-white);
        border: 1px solid var(--color-border);
        border-radius: var(--radius-xl);
        box-shadow: 0 20px 40px rgba(17, 24, 39, 0.1);
        padding: var(--space-8);
        opacity: 0;
        visibility: hidden;
        pointer-events: none;
        transform: translateY(10px);
        transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base);
        z-index: 1050;
    }

    /* Invisible hover buffer bridge to prevent menu from closing when mouse moves down */
    .mega-menu-wrapper::before {
        content: '';
        position: absolute;
        top: -16px;
        left: 0;
        right: 0;
        height: 16px;
    }

    .nav-item.has-mega-menu:hover .mega-menu-wrapper,
    .nav-item.has-mega-menu:focus-within .mega-menu-wrapper {
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
        transform: translateY(0);
    }
}

.mega-menu-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
}

.mega-menu-column h5 {
    font-size: var(--font-size-xs);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-primary-blue);
    font-weight: 700;
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-2);
    border-bottom: 1px solid var(--color-border);
}

.mega-menu-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.mega-menu-link {
    display: block;
    padding: var(--space-2) var(--space-2);
    border-radius: var(--radius-sm);
    color: var(--color-dark-gray);
    font-size: 0.875rem;
    font-weight: 500;
    transition: background-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
}

.mega-menu-link:hover {
    background-color: var(--color-light-gray);
    color: var(--color-primary-blue);
    transform: translateX(4px);
}

/* Nav Actions & Mobile Toggle */
.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--space-4);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 32px;
    height: 24px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1400;
    position: relative;
}

.menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--color-primary-navy);
    border-radius: var(--radius-xs);
    transition: transform var(--transition-smooth), opacity var(--transition-smooth);
}

/* Backdrop for Mobile Drawer */
.nav-backdrop {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    width: 100vw;
    height: 100vh;
    height: 100dvh;
    background: rgba(17, 24, 39, 0.5);
    z-index: 1150;
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}

.nav-backdrop.is-open {
    display: block;
    opacity: 1;
    pointer-events: auto;
}

/* ==========================================================================
   ENTERPRISE FOOTER ARCHITECTURE (Phase 16)
   ========================================================================== */
.site-footer {
    background-color: var(--color-primary-navy);
    color: rgba(255, 255, 255, 0.7);
    padding-top: clamp(64px, 8vw, 96px);
    padding-bottom: var(--space-8);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-top {
    display: grid;
    grid-template-columns: 2fr repeat(4, 1fr);
    gap: var(--space-8);
    padding-bottom: var(--space-12);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand .brand-logo {
    color: var(--color-white) !important;
    margin-bottom: var(--space-4);
}

.footer-brand .brand-logo:hover,
.footer-brand .brand-logo:focus,
.footer-brand .brand-logo:active,
.footer-brand .brand-logo:visited {
    color: var(--color-white) !important;
    text-decoration: none !important;
    transform: none !important;
    opacity: 1 !important;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9375rem;
    line-height: 1.6;
    max-width: 340px;
    margin-bottom: var(--space-6);
}

.footer-col h4 {
    color: var(--color-white);
    font-size: 0.9375rem;
    font-weight: 700;
    margin-bottom: var(--space-5);
    letter-spacing: -0.01em;
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.footer-links a {
    color: rgba(255, 255, 255, 0.65);
    font-size: 0.875rem;
    font-weight: 400;
    transition: color var(--transition-fast), transform var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-accent-blue);
    transform: translateX(2px);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-4);
    padding-top: var(--space-8);
    font-size: 0.8125rem;
    color: rgba(255, 255, 255, 0.5);
}

.footer-legal-links {
    display: flex;
    gap: var(--space-6);
}

.footer-legal-links a {
    color: rgba(255, 255, 255, 0.5);
    transition: color var(--transition-fast);
}

.footer-legal-links a:hover {
    color: var(--color-white);
}