/* ============================================================
   SV INSTITUTE – NAVBAR CSS
   Module 1: Desktop Sticky Nav · Mobile Drawer · Dropdown
   ============================================================ */

/* ── 1. HEADER WRAPPER ────────────────────────────────────── */
.svi-header {
  position:   fixed;
  top:        0;
  left:       0;
  right:      0;
  z-index:    var(--svi-z-nav);
  transition: background 0.35s ease, box-shadow 0.35s ease, padding 0.35s ease;
}

/* Transparent state (top of page) */
.svi-header--transparent .svi-navbar {
  background: transparent;
  box-shadow: none;
}
.svi-header--transparent .svi-logo-text__name  { color: var(--svi-white); }
.svi-header--transparent .svi-logo-text__tagline { color: rgba(255,255,255,0.6); }
.svi-header--transparent .svi-nav-desktop__link { color: rgba(255,255,255,0.88); }
.svi-header--transparent .svi-nav-desktop__link:hover { color: var(--svi-white); }
.svi-header--transparent .svi-hamburger__bar { background: var(--svi-white); }

/* Solid scrolled state */
.svi-navbar {
  background:  var(--svi-white);
  box-shadow:  0 2px 24px rgba(0,0,0,0.08);
  transition:  background 0.35s ease, box-shadow 0.35s ease;
}

/* ── 2. INNER LAYOUT ──────────────────────────────────────── */
.svi-navbar__inner {
  display:         flex;
  align-items:     center;
  justify-content: space-between;
  gap:             1.5rem;
  height:          var(--svi-nav-height);
}

/* ── 3. LOGO ──────────────────────────────────────────────── */
/* ── LOGO ──────────────────────────────────────────────── */
.svi-navbar__logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    flex-shrink: 0;
    width: auto;
}

.svi-logo-image {
    height: 55px;      /* Adjust logo size */
    width: auto;
    max-width: 180px; /* Prevent full screen stretch */
    display: block;
    object-fit: contain;
}

/* Remove old text/logo styles */
.svi-logo-text,
.svi-logo-mark {
    display: none;
}

/* ── 4. DESKTOP NAV ───────────────────────────────────────── */
.svi-nav-desktop { display: none; }

@media (min-width: 992px) {
  .svi-nav-desktop { display: flex; align-items: center; }
}

.svi-nav-desktop__list {
  display:     flex;
  align-items: center;
  gap:         0.25rem;
  list-style:  none;
  margin:      0;
  padding:     0;
}

.svi-nav-desktop__link {
  display:         inline-flex;
  align-items:     center;
  gap:             0.3rem;
  padding:         0.5rem 0.85rem;
  font-family:     var(--svi-font-heading);
  font-size:       var(--svi-text-sm);
  font-weight:     600;
  color:           var(--svi-navy);
  text-decoration: none;
  border-radius:   var(--svi-radius-sm);
  background:      none;
  border:          none;
  cursor:          pointer;
  white-space:     nowrap;
  transition:      color 0.2s, background 0.2s;
  position:        relative;
}
.svi-nav-desktop__link::after {
  content:          '';
  position:         absolute;
  bottom:           4px;
  left:             0.85rem;
  right:            0.85rem;
  height:           2px;
  border-radius:    var(--svi-radius-pill);
  background:       var(--svi-gradient);
  transform:        scaleX(0);
  transform-origin: left center;
  transition:       transform 0.25s ease;
}
.svi-nav-desktop__link:hover,
.svi-nav-desktop__link.active {
  color:      var(--svi-blue);
  background: var(--svi-blue-light);
}
.svi-nav-desktop__link:hover::after,
.svi-nav-desktop__link.active::after {
  transform: scaleX(1);
}
.svi-nav-desktop__link:focus-visible {
  outline:        2px solid var(--svi-blue);
  outline-offset: 2px;
}

/* Chevron rotation when dropdown open */
.svi-nav-desktop__dropdown-toggle[aria-expanded="true"] .bi-chevron-down {
  transform: rotate(180deg);
}
.svi-nav-desktop__dropdown-toggle .bi-chevron-down {
  font-size:  0.7rem;
  transition: transform 0.25s;
}

/* ── 5. DESKTOP DROPDOWN ──────────────────────────────────── */
.svi-nav-desktop__item--dropdown {
  position: relative;
}
.svi-dropdown {
  position:      absolute;
  top:           calc(100% + 8px);
  left:          50%;
  transform:     translateX(-50%) translateY(-8px);
  min-width:     220px;
  background:    var(--svi-white);
  border-radius: var(--svi-radius-md);
  box-shadow:    var(--svi-shadow-lg);
  border:        1px solid var(--svi-border);
  padding:       0.5rem;
  list-style:    none;
  margin:        0;
  opacity:       0;
  pointer-events: none;
  transition:    opacity 0.2s ease, transform 0.2s ease;
  z-index:       10;
}
.svi-nav-desktop__item--dropdown:hover .svi-dropdown,
.svi-nav-desktop__item--dropdown:focus-within .svi-dropdown {
  opacity:        1;
  pointer-events: auto;
  transform:      translateX(-50%) translateY(0);
}
.svi-dropdown__link {
  display:       block;
  padding:       0.6rem 0.85rem;
  font-size:     var(--svi-text-sm);
  font-weight:   500;
  color:         var(--svi-text);
  border-radius: var(--svi-radius-sm);
  text-decoration: none;
  transition:    background 0.18s, color 0.18s;
}
.svi-dropdown__link:hover {
  background: var(--svi-blue-light);
  color:      var(--svi-blue-dark);
}

/* ── 6. CTA BUTTON (desktop) ──────────────────────────────── */
.svi-navbar__cta { display: none; }

@media (min-width: 992px) {
  .svi-navbar__cta { display: flex; align-items: center; flex-shrink: 0; }
}

/* ── 7. HAMBURGER ─────────────────────────────────────────── */
.svi-hamburger {
  display:         flex;
  flex-direction:  column;
  justify-content: center;
  align-items:     center;
  gap:             5px;
  width:           44px;
  height:          44px;
  padding:         0;
  background:      none;
  border:          none;
  cursor:          pointer;
  border-radius:   var(--svi-radius-sm);
  flex-shrink:     0;
  transition:      background 0.2s;
}
.svi-hamburger:hover    { background: var(--svi-blue-light); }
.svi-hamburger:focus-visible {
  outline:        2px solid var(--svi-blue);
  outline-offset: 2px;
}
.svi-hamburger__bar {
  display:       block;
  width:         24px;
  height:        2px;
  border-radius: var(--svi-radius-pill);
  background:    var(--svi-navy);
  transition:    transform 0.3s ease, opacity 0.3s ease, width 0.3s ease;
  transform-origin: center;
}

/* Hamburger → X animation */
.svi-hamburger.is-open .svi-hamburger__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.svi-hamburger.is-open .svi-hamburger__bar:nth-child(2) {
  opacity:   0;
  transform: scaleX(0);
}
.svi-hamburger.is-open .svi-hamburger__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

@media (min-width: 992px) {
  .svi-hamburger { display: none; }
}

/* ── 8. MOBILE OVERLAY ────────────────────────────────────── */
.svi-nav-overlay {
  position:   fixed;
  inset:      0;
  background: rgba(0,0,0,0.5);
  z-index:    var(--svi-z-overlay);
  opacity:    0;
  pointer-events: none;
  transition: opacity 0.3s ease;
  backdrop-filter: blur(2px);
}
.svi-nav-overlay.is-visible {
  opacity:        1;
  pointer-events: auto;
}

/* ── 9. MOBILE DRAWER ─────────────────────────────────────── */
.svi-mobile-menu {
  position:       fixed;
  top:            0;
  right:          0;
  bottom:         0;
  width:          min(320px, 85vw);
  background:     var(--svi-white);
  z-index:        var(--svi-z-drawer);
  display:        flex;
  flex-direction: column;
  transform:      translateX(100%);
  transition:     transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  overflow-y:     auto;
  overscroll-behavior: contain;
  box-shadow:     -8px 0 40px rgba(0,0,0,0.15);
}
.svi-mobile-menu.is-open {
  transform: translateX(0);
}

/* Mobile menu header */
.svi-mobile-menu__header {
  display:         flex;
  align-items:     center;
  justify-content: space-between;
  padding:         1rem 1.25rem;
  border-bottom:   1px solid var(--svi-border);
  flex-shrink:     0;
}
.svi-mobile-menu__close {
  display:         flex;
  align-items:     center;
  justify-content: center;
  width:           40px;
  height:          40px;
  border-radius:   50%;
  background:      var(--svi-bg);
  border:          none;
  cursor:          pointer;
  font-size:       1.1rem;
  color:           var(--svi-navy);
  transition:      var(--svi-transition);
  flex-shrink:     0;
}
.svi-mobile-menu__close:hover { background: var(--svi-blue-light); color: var(--svi-blue); }

/* Mobile nav list */
.svi-mobile-nav { flex: 1; padding: 0.75rem 0; }
.svi-mobile-nav__list { display: flex; flex-direction: column; }
.svi-mobile-nav__item { border-bottom: 1px solid var(--svi-border); }

.svi-mobile-nav__link {
  display:         flex;
  align-items:     center;
  gap:             0.75rem;
  padding:         0.9rem 1.25rem;
  font-family:     var(--svi-font-heading);
  font-size:       var(--svi-text-sm);
  font-weight:     600;
  color:           var(--svi-navy);
  text-decoration: none;
  transition:      background 0.18s, color 0.18s;
  min-height:      52px;
}
.svi-mobile-nav__link i { font-size: 1rem; color: var(--svi-blue); width: 20px; }
.svi-mobile-nav__link.active,
.svi-mobile-nav__link:hover {
  background: var(--svi-blue-light);
  color:      var(--svi-blue-dark);
}

/* Accordion toggle */
.svi-mobile-nav__accordion-toggle {
  display:         flex;
  align-items:     center;
  justify-content: space-between;
  width:           100%;
  padding:         0.9rem 1.25rem;
  font-family:     var(--svi-font-heading);
  font-size:       var(--svi-text-sm);
  font-weight:     600;
  color:           var(--svi-navy);
  background:      none;
  border:          none;
  cursor:          pointer;
  text-align:      left;
  min-height:      52px;
  transition:      background 0.18s, color 0.18s;
}
.svi-mobile-nav__accordion-toggle span {
  display: flex; align-items: center; gap: 0.75rem;
}
.svi-mobile-nav__accordion-toggle span i { font-size: 1rem; color: var(--svi-blue); width: 20px; }
.svi-mobile-nav__accordion-toggle:hover { background: var(--svi-blue-light); color: var(--svi-blue-dark); }

.svi-mobile-nav__chevron {
  font-size:  0.75rem;
  transition: transform 0.3s ease;
}
.svi-mobile-nav__item--accordion.is-open .svi-mobile-nav__chevron {
  transform: rotate(180deg);
}

/* Accordion submenu */
.svi-mobile-nav__submenu {
  max-height: 0;
  overflow:   hidden;
  transition: max-height 0.35s ease;
  background: var(--svi-bg);
  list-style: none;
  padding:    0;
  margin:     0;
}
.svi-mobile-nav__item--accordion.is-open .svi-mobile-nav__submenu {
  max-height: 400px;
}
.svi-mobile-nav__sublink {
  display:         block;
  padding:         0.7rem 1.25rem 0.7rem 3.25rem;
  font-size:       var(--svi-text-sm);
  color:           var(--svi-text-muted);
  text-decoration: none;
  transition:      color 0.18s, background 0.18s;
  border-bottom:   1px solid rgba(0,0,0,0.04);
}
.svi-mobile-nav__sublink:hover { color: var(--svi-blue); background: var(--svi-blue-light); }

/* Mobile menu footer */
.svi-mobile-menu__footer {
  flex-shrink:  0;
  padding:      1.25rem;
  border-top:   1px solid var(--svi-border);
  background:   var(--svi-bg);
}
.svi-mobile-menu__contact-links {
  display:        flex;
  flex-direction: column;
  gap:            0.6rem;
  margin-top:     1rem;
}
.svi-mobile-menu__contact-links a {
  display:         flex;
  align-items:     center;
  gap:             0.6rem;
  font-size:       var(--svi-text-sm);
  font-weight:     600;
  color:           var(--svi-navy);
  text-decoration: none;
  transition:      color 0.2s;
}
.svi-mobile-menu__contact-links a i { color: var(--svi-blue); }
.svi-mobile-menu__contact-links a:hover { color: var(--svi-blue); }