/* ============================================
   MST Singapore — Layout v3 (Header, Footer)
   ============================================ */

/* === Header === */
.site-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--header-height);
    z-index: var(--z-header);
    transition: all var(--transition-base);
    background: rgba(241, 245, 249, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(15, 23, 42, 0.06);
}
.site-header.is-scrolled {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(24px) saturate(180%);
    -webkit-backdrop-filter: blur(24px) saturate(180%);
    border-bottom: 1px solid rgba(15, 23, 42, 0.06);
}
.site-header.is-scrolled .header-nav__link {
    color: var(--color-text-secondary);
}
.site-header.is-scrolled .header-nav__link:hover {
    color: var(--color-text);
    background: rgba(15, 23, 42, 0.04);
}
.site-header.is-scrolled .lang-toggle__btn { color: var(--color-text-tertiary); }
.site-header.is-scrolled .lang-toggle__btn.is-active { color: var(--color-text); }
.site-header.is-scrolled .lang-toggle__sep { color: rgba(15, 23, 42, 0.15); }
.site-header.is-scrolled .theme-toggle { color: var(--color-text-tertiary); }
.site-header.is-scrolled .mobile-toggle span { background: var(--color-text); }

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: var(--space-4);
}

/* Logo */
.header-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}
.header-logo__img {
    height: 40px;
    width: auto;
}

/* Desktop Nav */
.header-nav { display: flex; align-items: center; }
.header-nav__list { display: flex; align-items: center; gap: 2px; }
.header-nav__link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 8px 16px;
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 500;
    color: #475569;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    letter-spacing: var(--tracking-wide);
}
.header-nav__link:hover {
    color: #0f172a;
    background: rgba(15, 23, 42, 0.04);
}

/* Mega Menu */
.header-nav__has-dropdown { position: relative; }
.mega-menu {
    position: absolute;
    top: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%) translateY(6px);
    background: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(24px);
    border: 1px solid rgba(148, 163, 184, 0.08);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl), 0 0 60px rgba(0, 0, 0, 0.3);
    padding: var(--space-2);
    width: 480px;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: all var(--transition-base);
}
.header-nav__has-dropdown:hover .mega-menu {
    opacity: 1; visibility: visible; pointer-events: auto;
    transform: translateX(-50%) translateY(0);
}

.mega-menu__grid { display: grid; gap: 2px; }
.mega-menu__item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: 12px 16px;
    border-radius: var(--radius-lg);
    transition: background var(--transition-fast);
}
.mega-menu__item:hover { background: rgba(148, 163, 184, 0.06); }

.mega-menu__icon {
    width: 40px; height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    background: rgba(0, 212, 255, 0.06);
    color: var(--color-primary);
    flex-shrink: 0;
}

.mega-menu__content strong {
    display: block;
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-text);
}
.mega-menu__content span {
    font-size: var(--text-xs);
    color: var(--color-text-tertiary);
}

/* Header Actions */
.header-actions {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    flex-shrink: 0;
}

.lang-toggle {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: var(--text-sm);
    font-family: var(--font-display);
}
.lang-toggle__btn {
    padding: 4px 8px;
    border-radius: var(--radius-sm);
    color: #94a3b8;
    font-weight: 500;
    transition: all var(--transition-fast);
}
.lang-toggle__btn.is-active { color: #0f172a; }
.lang-toggle__btn:hover { color: #0f172a; }
.lang-toggle__sep { color: #cbd5e1; font-size: var(--text-xs); }

/* Theme toggle */
.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px; height: 36px;
    border: none;
    background: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    color: #94a3b8;
    transition: all var(--transition-fast);
}
.theme-toggle:hover {
    background: rgba(15, 23, 42, 0.04);
    color: #0f172a;
}
.theme-toggle__moon { display: none; }
[data-theme="dark"] .theme-toggle__sun { display: none; }
[data-theme="dark"] .theme-toggle__moon { display: block; }

/* Header CTA */
.header-cta {
    background: var(--color-primary) !important;
    color: var(--color-bg) !important;
    font-weight: 700 !important;
    box-shadow: 0 0 16px rgba(0, 212, 255, 0.25);
}
.header-cta:hover {
    box-shadow: 0 0 28px rgba(0, 212, 255, 0.4) !important;
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 36px; height: 36px;
    padding: 8px;
    border: none;
    background: none;
    cursor: pointer;
}
.mobile-toggle span {
    display: block;
    height: 2px;
    background: #475569;
    border-radius: 1px;
    transition: all var(--transition-base);
    transform-origin: center;
}
.mobile-toggle.is-active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.mobile-toggle.is-active span:nth-child(2) { opacity: 0; }
.mobile-toggle.is-active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    top: var(--header-height);
    left: 0; right: 0; bottom: 0;
    background: var(--color-bg);
    z-index: var(--z-mobile-menu);
    padding: var(--space-4) var(--space-4) var(--space-8);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    opacity: 0; visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-base);
    overflow-y: auto;
}
.mobile-menu.is-open {
    opacity: 1; visibility: visible;
    transform: translateY(0);
}

.mobile-menu__link {
    display: block;
    font-family: var(--font-display);
    font-size: var(--text-2xl);
    font-weight: 600;
    padding: var(--space-2) 0;
    border-bottom: 1px solid var(--color-border);
    color: var(--color-text);
}
.mobile-menu__sublink {
    display: block;
    font-family: var(--font-display);
    font-size: var(--text-base);
    padding: var(--space-1) 0 var(--space-1) var(--space-4);
    color: var(--color-text-tertiary);
}

@media (max-width: 1024px) {
    .header-nav, .header-cta { display: none; }
    .mobile-toggle { display: flex; }
}

/* === Footer === */
.site-footer {
    background: var(--color-bg-darker);
    color: var(--color-text);
    padding: var(--space-8) 0 var(--space-3);
    border-top: 1px solid var(--color-border);
    position: relative;
}
/* Top glow */
.site-footer::before {
    content: '';
    position: absolute;
    top: 0; left: 50%;
    transform: translateX(-50%);
    width: 500px; height: 1px;
    background: linear-gradient(90deg, transparent, rgba(0, 212, 255, 0.15), transparent);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: var(--space-6);
    margin-bottom: var(--space-6);
}
@media (max-width: 768px) {
    .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-4); }
}
@media (max-width: 480px) {
    .footer-grid { grid-template-columns: 1fr; }
}

.footer-logo {
    display: inline-block;
    margin-bottom: var(--space-1);
}
.footer-logo__text {
    font-family: var(--font-display);
    font-weight: 800;
    font-size: var(--text-2xl);
    color: var(--color-primary);
    letter-spacing: var(--tracking-wide);
}
.footer-brand__name {
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 600;
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: var(--space-2);
}
.footer-brand__desc {
    font-size: var(--text-sm);
    color: var(--color-text-tertiary);
    max-width: 260px;
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-3);
}
.footer-social { display: flex; gap: 10px; }
.footer-social a {
    display: flex; align-items: center; justify-content: center;
    width: 36px; height: 36px;
    border-radius: var(--radius-md);
    background: rgba(148, 163, 184, 0.04);
    border: 1px solid rgba(148, 163, 184, 0.06);
    color: var(--color-text-tertiary);
    transition: all var(--transition-fast);
}
.footer-social a:hover {
    background: rgba(0, 212, 255, 0.08);
    border-color: rgba(0, 212, 255, 0.15);
    color: var(--color-primary);
}

.footer-links__title {
    font-family: var(--font-display);
    font-size: 11px;
    font-weight: 700;
    color: var(--color-text-secondary);
    text-transform: uppercase;
    letter-spacing: var(--tracking-widest);
    margin-bottom: var(--space-3);
}
.footer-links ul { display: flex; flex-direction: column; gap: 10px; }
.footer-links a {
    display: inline-flex; align-items: center; gap: 4px;
    font-size: var(--text-sm);
    color: var(--color-text-tertiary);
    transition: color var(--transition-fast);
}
.footer-links a:hover { color: var(--color-primary); }

.footer-contact li {
    display: flex; align-items: center; gap: 8px;
    color: var(--color-text-tertiary);
}
.footer-contact a { color: var(--color-text-tertiary); }
.footer-contact a:hover { color: var(--color-primary); }

/* Ecosystem Bar */
.ecosystem-bar {
    display: flex; align-items: center; gap: var(--space-4);
    padding: var(--space-3) 0;
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    margin-bottom: var(--space-4);
    flex-wrap: wrap;
}
.ecosystem-bar__label {
    font-family: var(--font-display);
    font-size: 10px; font-weight: 700;
    text-transform: uppercase;
    letter-spacing: var(--tracking-widest);
    color: var(--color-text-tertiary);
}
.ecosystem-bar__links { display: flex; align-items: center; gap: var(--space-3); flex-wrap: wrap; }
.ecosystem-bar__link {
    display: inline-flex; align-items: center; gap: 4px;
    font-family: var(--font-display);
    font-size: var(--text-sm);
    color: var(--color-text-tertiary);
    font-weight: 500;
    transition: color var(--transition-fast);
}
.ecosystem-bar__link:hover { color: var(--color-primary); }

/* Footer Bottom */
.footer-bottom {
    display: flex; align-items: center;
    justify-content: space-between;
    flex-wrap: wrap; gap: var(--space-2);
}
.footer-bottom p { font-size: var(--text-xs); color: var(--color-text-tertiary); }
.footer-bottom__links { display: flex; gap: var(--space-3); }
.footer-bottom__links a {
    font-size: var(--text-xs); color: var(--color-text-tertiary);
    transition: color var(--transition-fast);
}
.footer-bottom__links a:hover { color: var(--color-text-secondary); }