/* ============================================================
   Vidyamrit — navbar.css
   Sticky site header, brand lockup, links + Programs dropdown,
   Register CTA, and the hamburger button base.
   Mobile drawer behaviour lives in responsive.css.
   ============================================================ */

html { scroll-padding-top: 92px; } /* keep anchors clear of the fixed header */

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid transparent;
  transition: box-shadow var(--t-med) var(--ease),
              background var(--t-med) var(--ease),
              border-color var(--t-med) var(--ease);
}
.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.96);
  box-shadow: var(--shadow-sm);
  border-bottom-color: var(--line);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 72px;
}

/* ---- Brand ---------------------------------------------- */
.brand { display: inline-flex; align-items: center; gap: 0.7rem; }
.brand__mark { width: 42px; height: 42px; }
.brand__text { display: flex; flex-direction: column; line-height: 1.1; }
.brand__name {
  font-weight: 700;
  font-size: 1.28rem;
  color: var(--royal-800);
  letter-spacing: -0.01em;
}
.brand__sub {
  font-family: var(--font-sanskrit);
  font-size: 0.72rem;
  color: var(--gold-600);
  letter-spacing: 0.02em;
}

/* ---- Menu wrapper --------------------------------------- */
.nav-menu { display: flex; align-items: center; gap: 1.6rem; }
.nav-list { display: flex; align-items: center; gap: 0.35rem; }

/* ---- Links ---------------------------------------------- */
.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.55rem 0.75rem;
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--ink);
  border-radius: var(--r-sm);
  transition: color var(--t-fast) var(--ease);
}
.nav-link::after {
  content: "";
  position: absolute;
  left: 0.75rem; right: 0.75rem; bottom: 0.28rem;
  height: 2px;
  background: linear-gradient(90deg, var(--gold-400), var(--gold-500));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-med) var(--ease);
  border-radius: 2px;
}
.nav-link:hover,
.nav-link.is-active { color: var(--royal-700); }
.nav-link:hover::after,
.nav-link.is-active::after { transform: scaleX(1); }
.nav-link--drop svg { width: 14px; height: 14px; transition: transform var(--t-fast) var(--ease); }

/* ---- Programs dropdown (desktop hover) ------------------ */
.has-dropdown { position: relative; }
.dropdown {
  position: absolute;
  top: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  min-width: 260px;
  padding: 0.5rem;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--t-med) var(--ease), transform var(--t-med) var(--ease);
}
.dropdown::before { /* hover bridge so it doesn't close between button and panel */
  content: ""; position: absolute; top: -12px; left: 0; right: 0; height: 12px;
}
.has-dropdown:hover .dropdown,
.has-dropdown:focus-within .dropdown {
  opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0);
}
.has-dropdown:hover .nav-link--drop svg { transform: rotate(180deg); }
.dropdown a {
  display: flex; flex-direction: column;
  padding: 0.7rem 0.85rem;
  border-radius: var(--r-sm);
  transition: background var(--t-fast) var(--ease);
}
.dropdown a strong { font-size: 0.95rem; color: var(--ink); font-weight: 600; }
.dropdown a small { font-size: 0.8rem; color: var(--muted); }
.dropdown a:hover { background: var(--royal-050); }
.dropdown a:hover strong { color: var(--royal-700); }

/* ---- CTA ------------------------------------------------- */
.nav-cta { padding: 0.65rem 1.3rem; font-size: 0.92rem; }

/* ---- Hamburger (shown on mobile via responsive.css) ----- */
.nav-toggle {
  display: none;
  width: 44px; height: 44px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border-radius: var(--r-sm);
}
.nav-toggle span {
  width: 24px; height: 2px;
  background: var(--royal-800);
  border-radius: 2px;
  transition: transform var(--t-med) var(--ease), opacity var(--t-fast) var(--ease);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Backdrop behind the mobile drawer */
.nav-backdrop {
  position: fixed; inset: 0;
  background: rgba(13, 31, 82, 0.42);
  backdrop-filter: blur(2px);
  opacity: 0; visibility: hidden;
  transition: opacity var(--t-med) var(--ease);
  z-index: 990;
}
.nav-backdrop.is-open { opacity: 1; visibility: visible; }

/* Spacer so page content clears the fixed header */
.header-spacer { height: 72px; }