/* ============================================================
   Navbar — 极简半透明导航 v3.0
   移动端：下滑隐藏/上滑显示 + 抽屉式菜单动画
   ============================================================ */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(8, 8, 8, 0.78);
  backdrop-filter: saturate(200%) blur(28px);
  -webkit-backdrop-filter: saturate(200%) blur(28px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  transition: background 0.5s var(--ease-out-quart),
              border-color 0.5s var(--ease-out-quart),
              height 0.4s var(--ease-out-quart),
              transform 0.45s var(--ease-out-expo);
  will-change: transform;
}

.navbar--scrolled {
  background: rgba(8, 8, 8, 0.94);
  border-bottom-color: rgba(255, 255, 255, 0.08);
  height: 64px;
}

/* 下滑隐藏 */
.navbar--hidden {
  transform: translateY(-100%);
}

.navbar__container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 48px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar__logo {
  display: flex;
  align-items: center;
  z-index: 1001;
  transition: transform 0.4s var(--ease-out-quart);
  text-decoration: none;
}

.navbar__logo:hover { transform: scale(1.04); }

.navbar__logo-img {
  height: 38px;
  width: auto;
  max-width: 180px;
  object-fit: contain;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.navbar__logo:hover .navbar__logo-img {
  opacity: 0.9;
}

.navbar__menu {
  display: flex;
  align-items: center;
  gap: 4px;
}

.navbar__item { position: relative; }

.navbar__link {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 9px 16px;
  font-size: 0.84rem;
  font-weight: 400;
  color: rgba(255, 255, 255, 0.62);
  border-radius: 8px;
  transition: all 0.28s ease;
  letter-spacing: 0.3px;
  cursor: pointer;
  text-decoration: none;
  position: relative;
}

.navbar__link:hover {
  color: rgba(255, 255, 255, 0.94);
  background: rgba(255, 255, 255, 0.05);
}

.navbar__link--active {
  color: #fff;
  font-weight: 600;
  background: rgba(255, 255, 255, 0.08);
}

.navbar__link--active::after {
  content: '';
  position: absolute;
  bottom: 6px;
  left: 50%;
  transform: translateX(-50%);
  width: 18px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  opacity: 0.9;
}

.navbar__item { position: relative; }

.navbar__link--active .navbar__chevron { opacity: 0.8; }

.navbar__chevron {
  font-size: 0.55rem;
  transition: transform 0.3s var(--ease-out-quart);
  opacity: 0.45;
  display: inline-block;
}

.navbar__chevron.rotated { transform: rotate(180deg); }

/* Dropdown */
.navbar__dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  min-width: 180px;
  background: rgba(20, 20, 20, 0.97);
  backdrop-filter: saturate(200%) blur(24px);
  -webkit-backdrop-filter: saturate(200%) blur(24px);
  border: 1px solid rgba(255, 255, 255, 0.07);
  border-radius: 12px;
  padding: 8px;
  opacity: 0;
  visibility: hidden;
  transition: all 0.28s var(--ease-out-quart);
  box-shadow: 0 20px 48px rgba(0, 0, 0, 0.4);
}

.navbar__dropdown--open {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.navbar__dropdown-link {
  display: block;
  padding: 11px 16px;
  font-size: 0.82rem;
  font-weight: 400;
  color: rgba(255, 255, 255, 0.58);
  border-radius: 8px;
  transition: all 0.22s ease;
  white-space: nowrap;
  letter-spacing: 0.3px;
  text-decoration: none;
}

.navbar__dropdown-link:hover {
  color: rgba(255, 255, 255, 0.94);
  background: rgba(255, 255, 255, 0.06);
}

/* Hamburger */
.navbar__hamburger {
  display: none;
  z-index: 1001;
  color: rgba(255, 255, 255, 0.65);
  padding: 6px;
  transition: color 0.2s, transform 0.3s var(--ease-spring);
  -webkit-tap-highlight-color: transparent;
}

.navbar__hamburger:hover { color: rgba(255, 255, 255, 0.95); }

/* ========== 移动端覆盖层 ========== */
.body--menu-open {
  overflow: hidden;
}

/* Mobile */
@media (max-width: 968px) {
  .navbar__container { padding: 0 20px; }
  .navbar__hamburger { display: flex; }

  .navbar__nav {
    position: fixed;
    top: 0; right: -320px;
    width: 300px;
    height: 100vh;
    height: 100dvh;
    background: rgba(8, 8, 8, 0.98);
    backdrop-filter: blur(36px);
    -webkit-backdrop-filter: blur(36px);
    padding: calc(var(--header-height) + 40px) 24px 28px;
    transition: right 0.45s var(--ease-out-expo);
    overflow-y: auto;
    box-shadow: -10px 0 40px rgba(0, 0, 0, 0.3);
    z-index: 1000;
  }

  .navbar__nav--open { right: 0; }

  .navbar__menu {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .navbar__item {
    opacity: 0;
    transform: translateX(30px);
    transition: opacity 0.4s var(--ease-out-expo), transform 0.4s var(--ease-out-expo);
  }

  .navbar__nav--open .navbar__item {
    opacity: 1;
    transform: translateX(0);
  }

  .navbar__nav--open .navbar__item:nth-child(1) { transition-delay: 0.06s; }
  .navbar__nav--open .navbar__item:nth-child(2) { transition-delay: 0.1s; }
  .navbar__nav--open .navbar__item:nth-child(3) { transition-delay: 0.14s; }
  .navbar__nav--open .navbar__item:nth-child(4) { transition-delay: 0.18s; }
  .navbar__nav--open .navbar__item:nth-child(5) { transition-delay: 0.22s; }
  .navbar__nav--open .navbar__item:nth-child(6) { transition-delay: 0.26s; }
  .navbar__nav--open .navbar__item:nth-child(7) { transition-delay: 0.3s; }

  .navbar__link {
    width: 100%;
    padding: 15px 18px;
    font-size: 0.95rem;
    justify-content: space-between;
    border-radius: 10px;
  }

  .navbar__dropdown {
    position: static; transform: none;
    opacity: 1; visibility: visible;
    background: transparent;
    border: none; padding: 0; box-shadow: none;
    margin: 2px 0 4px 18px;
    border-left: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 0;
    display: none;
  }

  .navbar__dropdown--open { display: block; }

  .navbar__dropdown-link {
    padding: 11px 18px;
    font-size: 0.87rem;
    opacity: 0;
    transform: translateX(15px);
    transition: opacity 0.3s ease, transform 0.3s ease, color 0.22s ease, background 0.22s ease;
  }

  .navbar__dropdown--open .navbar__dropdown-link {
    opacity: 1;
    transform: translateX(0);
  }

  .navbar__dropdown--open .navbar__dropdown-link:nth-child(1) { transition-delay: 0.05s; }
  .navbar__dropdown--open .navbar__dropdown-link:nth-child(2) { transition-delay: 0.09s; }
  .navbar__dropdown--open .navbar__dropdown-link:nth-child(3) { transition-delay: 0.13s; }
  .navbar__dropdown--open .navbar__dropdown-link:nth-child(4) { transition-delay: 0.17s; }
  .navbar__dropdown--open .navbar__dropdown-link:nth-child(5) { transition-delay: 0.21s; }
  .navbar__dropdown--open .navbar__dropdown-link:nth-child(6) { transition-delay: 0.25s; }
}

@media (max-width: 480px) {
  .navbar__nav { width: 280px; }
  .navbar__logo-img { height: 32px; max-width: 140px; }
  .navbar__logo-icon { width: 34px; height: 34px; border-radius: 8px; }
}