/* ===================================================
   GSAf — Navigation Stylesheet (nav.css)
   =================================================== */

/* ---------- HEADER BASE ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: var(--white);
  height: var(--header-h);
  display: flex;
  align-items: center;
  border-bottom: 1px solid var(--border);
  transition: box-shadow var(--transition), background var(--transition);
}
.site-header.scrolled {
  box-shadow: 0 4px 24px rgba(0,0,0,0.1);
}

.header-inner {
  width: 100%;
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}

/* ---------- LOGO ---------- */
.site-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  flex-shrink: 0;
}
.logo-icon {
  width: 44px; height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--dark));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.4rem;
}
.logo-text { line-height: 1; }
.logo-main {
  display: block;
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--dark);
}
.logo-sub {
  display: block;
  font-size: 0.62rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  margin-top: 2px;
}

/* ---------- MAIN NAV ---------- */
.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
  flex: 1;
  justify-content: flex-end;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  list-style: none;
  margin: 0; padding: 0;
}

/* NAV ITEM */
.nav-item { position: relative; }

.nav-link {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 8px 12px;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text);
  border-radius: 6px;
  transition: all var(--transition);
  white-space: nowrap;
  text-decoration: none;
  border: none;
  background: none;
  cursor: pointer;
  font-family: var(--font-body);
}
.nav-link:hover, .nav-link.active {
  color: var(--primary);
  background: var(--primary-light);
}
.nav-arrow {
  font-size: 0.6rem;
  transition: transform var(--transition);
}
.nav-item:hover .nav-arrow { transform: rotate(180deg); }
.nav-external { color: var(--primary); }
.nav-ext-icon { font-size: 0.65rem; opacity: 0.7; }

/* DROPDOWN */
.dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  min-width: 220px;
  padding: 8px;
  list-style: none;
  opacity: 0;
  pointer-events: none;
  transform: translateX(-50%) translateY(-8px);
  transition: opacity var(--transition), transform var(--transition);
  z-index: 200;
}
.nav-item:hover .dropdown-menu {
  opacity: 1;
  pointer-events: all;
  transform: translateX(-50%) translateY(0);
}
.dropdown-menu li a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 14px;
  border-radius: 6px;
  font-size: 0.85rem;
  color: var(--text);
  text-decoration: none;
  transition: all var(--transition);
}
.dropdown-menu li a:hover {
  background: var(--primary-light);
  color: var(--primary);
  padding-left: 18px;
}
.dropdown-menu li a i {
  width: 16px;
  text-align: center;
  color: var(--primary);
  font-size: 0.85rem;
}
.dropdown-divider {
  border-top: 1px solid var(--border);
  margin: 6px 8px;
}

/* NAV AUTH BUTTONS */
.nav-auth {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-left: 16px;
  flex-shrink: 0;
}
.btn-nav-login {
  padding: 7px 16px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition);
}
.btn-nav-login:hover {
  border-color: var(--primary);
  color: var(--primary);
}
.btn-nav-join {
  padding: 8px 18px;
  font-size: 0.82rem;
  font-weight: 600;
  background: var(--primary);
  color: var(--white);
  border-radius: 6px;
  text-decoration: none;
  transition: all var(--transition);
  white-space: nowrap;
}
.btn-nav-join:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0,86,179,0.3);
}

/* ---------- HAMBURGER ---------- */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
  cursor: pointer;
  margin-left: auto;
  background: none;
  border: none;
}
.bar {
  width: 24px;
  height: 2.5px;
  background: var(--text);
  border-radius: 4px;
  transition: all 0.3s ease;
  display: block;
}
.hamburger.open .bar:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.hamburger.open .bar:nth-child(2) { opacity: 0; transform: scaleX(0); }
.hamburger.open .bar:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* ---------- MOBILE OVERLAY ---------- */
.mobile-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 998;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
  backdrop-filter: blur(4px);
}
.mobile-overlay.visible {
  opacity: 1;
  pointer-events: all;
}

/* ---------- MOBILE DRAWER ---------- */
.mobile-nav {
  position: fixed;
  top: 0; right: 0;
  width: min(360px, 90vw);
  height: 100vh;
  background: var(--white);
  z-index: 999;
  transform: translateX(100%);
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}
.mobile-nav.open {
  transform: translateX(0);
  box-shadow: -8px 0 40px rgba(0,0,0,0.15);
}

.mobile-nav-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.mobile-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--dark);
}
.mobile-logo i { color: var(--primary); font-size: 1.5rem; }
.mobile-close {
  width: 36px; height: 36px;
  background: var(--bg-light);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  font-size: 1rem;
  transition: background var(--transition);
}
.mobile-close:hover { background: var(--border); }

.mobile-nav-list {
  flex: 1;
  padding: 16px 0;
  list-style: none;
  overflow-y: auto;
}
.mobile-nav-list > li > a,
.mobile-sub-toggle {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 24px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text);
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-body);
  text-decoration: none;
  transition: all var(--transition);
}
.mobile-nav-list > li > a:hover,
.mobile-sub-toggle:hover { background: var(--bg-light); color: var(--primary); }
.mobile-sub-toggle { justify-content: space-between; }
.mobile-sub-toggle span { display: flex; align-items: center; gap: 12px; }
.mobile-sub-toggle .fa-chevron-down {
  font-size: 0.75rem;
  transition: transform 0.3s;
  margin-left: auto;
}
.mobile-has-sub.open .fa-chevron-down { transform: rotate(180deg); }

.mobile-submenu {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
  background: var(--bg-light);
  list-style: none;
}
.mobile-has-sub.open .mobile-submenu { max-height: 500px; }
.mobile-submenu li a {
  display: block;
  padding: 10px 24px 10px 50px;
  font-size: 0.88rem;
  color: var(--text-light);
  text-decoration: none;
  transition: all var(--transition);
}
.mobile-submenu li a:hover { color: var(--primary); padding-left: 56px; }

.mobile-nav-footer {
  padding: 20px 24px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 10px;
  flex-shrink: 0;
}
.mobile-btn { width: 100%; justify-content: center; }

/* ---- RESPONSIVE BREAKPOINT ---- */
@media (max-width: 1024px) {
  .main-nav { display: none !important; }
  .hamburger { display: flex; }
}

@media (min-width: 1025px) {
  .mobile-nav,
  .mobile-overlay { display: none !important; }
}