/* ============================================================
   星冕 VR3D — Header & Navigation (统一 Header，全部前台页面共用)
   ============================================================ */

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: 76px;
  display: flex;
  align-items: center;
  transition: transform .5s var(--ease), background-color .5s;
}

/* 顶部吸附形态：进入滚动后玻璃化 */
.site-header.is-solid {
  background: var(--glass-bg-strong);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
  backdrop-filter: blur(20px) saturate(1.4);
  border-bottom: 1px solid var(--glass-border);
}
.site-header.is-hidden { transform: translateY(-100%); }

.header-container {
  width: min(1680px, 100% - clamp(24px, 5vw, 80px));
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* Logo */
.logo {
  display: inline-flex;
  align-items: baseline;
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -.02em;
  color: var(--text);
}
.logo .dot {
  color: var(--neon);
  text-shadow: var(--glow-accent);
}
.logo .tagline {
  margin-left: 10px;
  font-size: .62rem;
  letter-spacing: .3em;
  font-weight: 600;
  color: var(--text-3);
  text-transform: uppercase;
}

/* Nav */
.main-nav { display: flex; align-items: center; gap: 4px; }
.nav-link {
  position: relative;
  padding: 9px 16px;
  border-radius: var(--r-pill);
  font-size: .92rem;
  font-weight: 500;
  color: var(--text-2);
  transition: color .3s, background .3s;
}
.nav-link:hover { color: var(--text); background: var(--glass-highlight); }
.nav-link.is-active { color: var(--text); font-weight: 700; }
.nav-link.is-active::after {
  content: "";
  position: absolute;
  left: 16px; right: 16px; bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--neon-grad);
  box-shadow: var(--glow-accent);
}

.header-actions { display: flex; align-items: center; gap: 10px; }

/* Theme toggle */
.theme-toggle { position: relative; }
.theme-toggle .icon-sun,
.theme-toggle .icon-moon { position: absolute; inset: 0; transition: all .35s var(--ease); }

html[data-theme="dark"] .theme-toggle .icon-sun { opacity: 0; transform: rotate(90deg) scale(.5); }
html[data-theme="dark"] .theme-toggle .icon-moon { opacity: 1; transform: none; }
html[data-theme="light"] .theme-toggle .icon-sun { opacity: 1; transform: none; }
html[data-theme="light"] .theme-toggle .icon-moon { opacity: 0; transform: rotate(-90deg) scale(.5); }

/* Mobile menu button */
.menu-button { display: none; }

/* Mobile drawer */
.mobile-drawer {
  position: fixed;
  inset: 0;
  z-index: 95;
  pointer-events: none;
  visibility: hidden;
}
.mobile-drawer .drawer-backdrop {
  position: absolute;
  inset: 0;
  background: var(--overlay);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
  opacity: 0;
  transition: opacity .4s;
}
.mobile-drawer .drawer-panel {
  position: absolute;
  inset: 0 0 0 auto;
  width: min(86vw, 420px);
  background: var(--bg-elev);
  border-left: 1px solid var(--border);
  padding: 96px 34px 40px;
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform .5s var(--ease-out);
  overflow-y: auto;
}
.mobile-drawer.open { pointer-events: auto; visibility: visible; }
.mobile-drawer.open .drawer-backdrop { opacity: 1; }
.mobile-drawer.open .drawer-panel { transform: none; }

.drawer-link {
  padding: 15px 4px;
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--text);
  border-bottom: 1px solid var(--border-soft);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.drawer-link small {
  font-size: .7rem;
  color: var(--text-3);
  letter-spacing: .2em;
  text-transform: uppercase;
  font-weight: 600;
}
.drawer-link:hover { color: var(--neon); }
.drawer-footer-links {
  margin-top: auto;
  padding-top: 28px;
  display: flex;
  gap: 14px;
  color: var(--text-3);
}
.drawer-footer-links a:hover { color: var(--neon); }

@media (max-width: 1024px) {
  .main-nav { display: none; }
  .menu-button { display: inline-grid; }
}