/* ========== 顶级导航栏 ========== */
.navbar {
  position: absolute; 
  top: 0; left: 0; right: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 3rem;
  background: var(--nav-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--glass-border);
  z-index: 1000;
  transition: all 0.3s ease;
  view-transition-name: header-nav;
}

.navbar.fixed {
  position: fixed;
  animation: slideDownNav 0.4s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
  box-shadow: 0 4px 30px rgba(0,0,0,0.1);
}
@keyframes slideDownNav {
  from { transform: translateY(-100%); }
  to { transform: translateY(0); }
}

.navbar-brand {
  font-size: 1.6rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--secondary), var(--primary));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: 2px;
}

.navbar-menu { display: flex; gap: 2.5rem; align-items: center; }
.navbar-menu .nav-link { 
  font-weight: 600; 
  transition: 0.3s; 
  color: var(--text-main); 
  position: relative; 
  padding-bottom: 4px;
}
.navbar-menu .nav-link:hover { color: var(--primary); text-shadow: 0 0 10px var(--primary-glow); }
.navbar-menu .nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px; 
  left: 0;
  width: 100%; 
  height: 4px; 
  border-radius: 2px;
  background: var(--primary);
  box-shadow: 0 0 10px var(--primary-glow);
  transform: scaleX(0); 
  transform-origin: center; 
  transition: transform 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
}
.navbar-menu .nav-link:hover::after {
  transform: scaleX(1); 
}

/* ========== 下拉菜单 ========== */
.nav-dropdown {
  position: relative;
  display: flex;
  align-items: center;
  gap: 2px;
}

/* 下拉箭头 */
.nav-dropdown-arrow {
  color: var(--text-muted);
  transition: transform 0.3s ease;
  user-select: none;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-left: 2px;
}
.nav-dropdown:hover .nav-dropdown-arrow {
  transform: rotate(180deg);
  color: var(--primary);
}

/* 下拉面板 */
.nav-dropdown-menu {
  position: absolute;
  top: calc(100% + 14px);
  left: 50%;
  transform: translateX(-50%);
  min-width: 140px;
  background: rgba(11, 17, 32, 0.85);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--glass-border);
  border-radius: 14px;
  padding: 8px 0;
  box-shadow: 0 12px 40px rgba(0,0,0,0.35);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateX(-50%) translateY(-6px);
  transition: opacity 0.25s ease, visibility 0.25s ease, transform 0.25s cubic-bezier(0.2,0.8,0.2,1);
  z-index: 2000;
}
:root.light-mode .nav-dropdown-menu {
  background: rgba(248, 250, 252, 0.92);
}

/* 触发显示 */
.nav-dropdown:hover .nav-dropdown-menu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

/* 透明桥接区：填充触发元素与面板之间的间隙，防止中途 hover 断开 */
.nav-dropdown-menu::after {
  content: '';
  position: absolute;
  top: -14px;
  left: 0;
  right: 0;
  height: 14px;
}

/* 面板头部小三角 */
.nav-dropdown-menu::before {
  content: '';
  position: absolute;
  top: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 12px;
  height: 6px;
  background: var(--glass-border);
  clip-path: polygon(50% 0%, 0% 100%, 100% 100%);
}

/* 子菜单项 */
.nav-dropdown-item {
  display: block;
  padding: 10px 18px;
  margin: 4px 8px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
  white-space: nowrap;
  position: relative;
  border-radius: 8px;
  overflow: hidden;
}

/* 霓虹发光左边框效果 */
.nav-dropdown-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%) scaleY(0);
  width: 3px;
  height: 50%;
  background: var(--primary);
  box-shadow: 0 0 8px var(--primary-glow);
  border-radius: 4px;
  transition: transform 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
  opacity: 0;
}

.nav-dropdown-item:hover {
  color: var(--primary);
  background: rgba(236, 72, 153, 0.08); /* 兼容之前版本配置的粉色底 */
  padding-left: 24px;
  text-shadow: 0 0 8px rgba(236, 72, 153, 0.3);
}

.nav-dropdown-item:hover::before {
  transform: translateY(-50%) scaleY(1);
  opacity: 1;
}

.theme-toggle-btn {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  color: var(--text-main);
  border-radius: 50%;
  width: 40px; height: 40px;
  display: flex; align-items: center; justify-content: center;
  transition: 0.3s;
  outline: none;
}
.theme-toggle-btn:hover { background: var(--secondary); color: #fff; transform: rotate(30deg); }

/* ========== 新版精美的底部 ========== */
.footer {
  position: relative;
  margin-top: 2rem;
  padding: 3rem 0;
  background: var(--footer-bg);
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  border-top: 1px solid var(--glass-border);
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-muted);
  overflow: hidden;
  clear: both;
}
.footer-line {
  position: absolute;
  top: 0; left: 50%;
  transform: translateX(-50%);
  width: 100px; height: 3px;
  background: var(--primary);
  box-shadow: 0 0 15px var(--primary-glow);
  border-radius: 0 0 4px 4px;
  animation: pulseLine 2s infinite;
}
@keyframes pulseLine {
  0%, 100% { width: 100px; opacity: 0.5; }
  50% { width: 300px; opacity: 1; }
}
.footer p { margin-bottom: 0.5rem; position: relative; z-index: 2; }
.footer a { color: var(--secondary); font-weight: 600; transition: 0.3s; position: relative; }
.footer a:hover { color: var(--primary); }

/* ========== 备案信息样式 ========== */
.footer-beian {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1.2rem;
  margin-top: 0.6rem;
  padding-top: 0.6rem;
  border-top: 1px solid var(--glass-border);
  position: relative;
  z-index: 2;
}

/* 每条备案链接 */
.beian-item {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  color: var(--text-muted) !important;
  font-size: 0.82rem;
  font-weight: 400 !important;
  transition: color 0.3s;
  text-decoration: none;
}
.beian-item:hover {
  color: var(--primary) !important;
}

/* 公安网备图标 */
.beian-police-icon {
  width: 16px;
  height: 16px;
  vertical-align: middle;
  object-fit: contain;
  flex-shrink: 0;
}

/* ========== 通用短巨幕（标签/分类/归档等子页面） ========== */
.hero {
  position: relative;
  height: 45vh;
  min-height: 280px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}
.hero .hero-bg {
  position: absolute;
  inset: 0;
  background: url('../images/hero-bg.jpg') center/cover;
  opacity: 0.4;
  z-index: -1;
  mask-image: linear-gradient(to bottom, black 50%, transparent 100%);
  -webkit-mask-image: linear-gradient(to bottom, black 50%, transparent 100%);
  transition: opacity 0.5s;
}
.hero .hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  margin-bottom: 1rem;
  animation: heroTitleIn 1s cubic-bezier(0.2, 0.8, 0.2, 1);
}
@keyframes heroTitleIn {
  from { opacity: 0; transform: scale(0.9) translateY(-20px); filter: blur(10px); }
  to { opacity: 1; transform: scale(1) translateY(0); filter: blur(0); }
}

/* 响应式支持 */
@media (max-width: 768px) {
  .navbar-menu { display: none; }
  #toggle-3d-btn { display: none; }
  .hero .hero-title { font-size: 2.2rem; }
}