/* ============================================================
   OXFORDIAN HEADER & NAVIGATION
   ============================================================ */

/* ---- Top Bar ---- */
.ox-topbar {
  background: var(--ox-navy);
  color: rgba(255,255,255,0.85);
  padding: 0.5rem 0;
  font-size: var(--text-xs);
  font-family: var(--font-heading);
  letter-spacing: 0.04em;
  position: relative;
  z-index: 1001;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.ox-topbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.ox-topbar__left {
  display: flex;
  align-items: center;
  gap: var(--space-5);
}

.ox-topbar__right {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.topbar-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: rgba(255,255,255,0.75);
  transition: color var(--duration-fast) var(--ease-smooth);
}

.topbar-item:hover { color: var(--ox-gold); }

.topbar-item svg {
  width: 13px;
  height: 13px;
  color: var(--ox-red);
  flex-shrink: 0;
}

.topbar-admission-badge {
  background: var(--ox-red);
  color: var(--ox-white);
  padding: 0.2rem 0.875rem;
  border-radius: var(--radius-full);
  font-weight: 700;
  letter-spacing: 0.08em;
  animation: topbar-pulse 2.5s infinite;
}

@keyframes topbar-pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(192,39,45,0.5); }
  50% { box-shadow: 0 0 0 8px rgba(192,39,45,0); }
}

/* ---- Main Header ---- */
.ox-header {
  position: sticky;
  top: 0;
  width: 100%;
  z-index: 1000;
  transition: all var(--duration-slow) var(--ease-smooth);
  background: var(--ox-white);
  border-bottom: 1px solid var(--ox-gray-200);
  height: var(--header-height);
  display: flex;
  align-items: center;
}

.ox-header.scrolled {
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 4px 24px rgba(10,22,40,0.10);
  border-bottom-color: transparent;
}

.ox-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  gap: var(--space-6);
}

/* ---- Logo ---- */
.ox-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  flex-shrink: 0;
}

.ox-logo__img {
  height: 52px;
  width: auto;
  transition: transform var(--duration-base) var(--ease-smooth);
}

.ox-logo:hover .ox-logo__img {
  transform: scale(1.03);
}

.ox-logo__text {
  display: flex;
  flex-direction: column;
}

.ox-logo__name {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--ox-navy);
  line-height: 1.1;
  letter-spacing: -0.01em;
}

.ox-logo__tagline {
  font-family: var(--font-heading);
  font-size: 0.6rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ox-red);
}

/* ---- Navigation ---- */
.ox-nav {
  display: flex;
  align-items: center;
  gap: 0;
}

.ox-nav__menu {
  display: flex;
  align-items: center;
  gap: 0;
  list-style: none;
}

.ox-nav__item {
  position: relative;
}

.ox-nav__link {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: 0.625rem 1.125rem;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--ox-gray-700);
  letter-spacing: 0.02em;
  transition: color var(--duration-fast) var(--ease-smooth);
  border-radius: var(--radius-md);
  position: relative;
}

.ox-nav__link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: calc(100% - 2rem);
  height: 2px;
  background: var(--ox-red);
  border-radius: var(--radius-full);
  transition: transform var(--duration-base) var(--ease-spring);
}

.ox-nav__link:hover,
.ox-nav__link.active {
  color: var(--ox-navy);
}

.ox-nav__link:hover::after,
.ox-nav__link.active::after {
  transform: translateX(-50%) scaleX(1);
}

/* Dropdown chevron */
.nav-chevron {
  width: 14px;
  height: 14px;
  transition: transform var(--duration-base) var(--ease-smooth);
}

.ox-nav__item:hover .nav-chevron {
  transform: rotate(180deg);
}

/* ---- Dropdown ---- */
.ox-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  min-width: 220px;
  background: var(--ox-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--ox-gray-200);
  padding: var(--space-2) 0;
  opacity: 0;
  visibility: hidden;
  transition: all var(--duration-base) var(--ease-smooth);
  z-index: 100;
}

.ox-dropdown::before {
  content: '';
  position: absolute;
  top: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 12px;
  height: 12px;
  background: var(--ox-white);
  border-left: 1px solid var(--ox-gray-200);
  border-top: 1px solid var(--ox-gray-200);
  transform: translateX(-50%) rotate(45deg);
}

.ox-nav__item:hover .ox-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.ox-dropdown__link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 0.625rem 1.25rem;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--ox-gray-700);
  transition: all var(--duration-fast) var(--ease-smooth);
}

.ox-dropdown__link:hover {
  background: var(--ox-gray-100);
  color: var(--ox-red);
  padding-left: 1.5rem;
}

.ox-dropdown__link .dd-icon {
  width: 16px;
  height: 16px;
  color: var(--ox-red);
  opacity: 0.7;
}

/* ---- Header CTA ---- */
.ox-header__cta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

.header-apply-btn {
  background: #C0272C !important;
  color: var(--ox-white) !important;
  padding: 0.625rem 1.5rem !important;
  border-radius: var(--radius-full) !important;
  font-family: var(--font-heading) !important;
  font-size: var(--text-sm) !important;
  font-weight: 700 !important;
  letter-spacing: 0.04em !important;
  text-transform: uppercase !important;
  transition: all var(--duration-base) var(--ease-smooth) !important;
  display: inline-flex !important;
  align-items: center !important;
  gap: var(--space-2) !important;
  box-shadow: var(--shadow-red) !important;
  position: relative !important;
  overflow: hidden !important;
}

.header-apply-btn:hover {
  background: #961E22 !important;
  transform: translateY(-1px) !important;
  box-shadow: 0 8px 24px rgba(192,39,45,0.40) !important;
}

/* ---- Hamburger (Mobile) ---- */
.ox-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  cursor: pointer;
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  padding: 0.5rem;
  transition: background var(--duration-fast) var(--ease-smooth);
}

.ox-hamburger:hover {
  background: var(--ox-gray-100);
}

.ox-hamburger__bar {
  width: 24px;
  height: 2px;
  background: var(--ox-navy);
  border-radius: 2px;
  transition: all var(--duration-base) var(--ease-smooth);
  transform-origin: center;
}

.ox-hamburger.is-open .ox-hamburger__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.ox-hamburger.is-open .ox-hamburger__bar:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.ox-hamburger.is-open .ox-hamburger__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---- Mobile Menu ---- */
.ox-mobile-menu {
  display: none;
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--ox-white);
  z-index: 999;
  overflow-y: auto;
  padding: var(--space-6) var(--space-6) var(--space-12);
  transform: translateX(100%);
  transition: transform var(--duration-slow) var(--ease-expo);
}

.ox-mobile-menu.is-open {
  transform: translateX(0);
}

.ox-mobile-nav__link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) 0;
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--ox-navy);
  border-bottom: 1px solid var(--ox-gray-200);
  transition: color var(--duration-fast) var(--ease-smooth);
}

.ox-mobile-nav__link:hover { color: var(--ox-red); }

.mobile-menu-cta {
  margin-top: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

/* ---- Responsive Header ---- */
@media (max-width: 1080px) {
  .ox-nav { display: none; }
  .ox-hamburger { display: flex; }
  .ox-mobile-menu { display: block; }
  .ox-topbar__left { display: none; }
}

@media (max-width: 640px) {
  .ox-topbar { display: none; }
  .ox-logo__text { display: none; }
}