/* 主题切换：旧背景短暂保留并淡出，让两张底图自然交接。 */
#web_bg.theme-crossfade::after {
  position: absolute;
  inset: 0;
  z-index: 4;
  background-image: var(--theme-previous-background);
  background-position: var(--theme-previous-position, center center);
  background-size: cover;
  background-repeat: no-repeat;
  content: '';
  opacity: 1;
  pointer-events: none;
}

#web_bg.theme-crossfade.theme-crossfade-run::after {
  opacity: 0;
  transition: opacity 0.82s cubic-bezier(0.22, 1, 0.36, 1);
}

body,
#nav,
.card-widget,
.recent-post-item,
.layout > div:first-child:not(.nc),
#footer,
#site-title,
#site-subtitle,
#aside-content .card-info,
#nav .site-page {
  transition:
    color 0.55s ease,
    background-color 0.55s ease,
    border-color 0.55s ease,
    box-shadow 0.55s ease,
    text-shadow 0.55s ease;
}

/* 夜间动态霓虹：标题、个人卡片和菜单使用不同强度，避免整页过亮。 */
[data-theme='dark'] #site-title {
  color: #eefaff;
  text-shadow:
    0 0 5px rgba(255, 255, 255, 0.92),
    0 0 13px rgba(99, 210, 255, 0.9),
    0 0 30px rgba(77, 121, 255, 0.72);
  animation: neonTitlePulse 3.4s ease-in-out infinite;
}

[data-theme='dark'] #site-subtitle {
  color: #d9f5ff;
  text-shadow:
    0 0 5px rgba(161, 229, 255, 0.84),
    0 0 14px rgba(92, 156, 255, 0.72);
  animation: neonSubtitlePulse 4.2s ease-in-out -1.1s infinite;
}

[data-theme='dark'] #aside-content .card-info {
  border: 1px solid rgba(102, 211, 255, 0.38);
  box-shadow:
    0 0 12px rgba(68, 179, 255, 0.2),
    inset 0 0 18px rgba(74, 111, 255, 0.08);
  animation: neonCardPulse 4.8s ease-in-out infinite;
}

[data-theme='dark'] #aside-content .card-info .avatar-img {
  box-shadow:
    0 0 10px rgba(115, 225, 255, 0.58),
    0 0 24px rgba(85, 126, 255, 0.4);
}

[data-theme='dark'] #aside-content .author-info-name,
[data-theme='dark'] #aside-content .author-info-description,
[data-theme='dark'] #aside-content .site-data {
  text-shadow:
    0 0 5px rgba(142, 224, 255, 0.58),
    0 0 11px rgba(95, 134, 255, 0.35);
}

[data-theme='dark'] #nav .site-page,
[data-theme='dark'] #sidebar-menus .site-page {
  color: #e6f8ff;
  text-shadow:
    0 0 4px rgba(198, 242, 255, 0.9),
    0 0 9px rgba(82, 192, 255, 0.72);
}

[data-theme='dark'] #nav .site-page:hover,
[data-theme='dark'] #sidebar-menus .site-page:hover {
  color: #fff;
  text-shadow:
    0 0 5px #fff,
    0 0 12px rgba(85, 220, 255, 0.95),
    0 0 20px rgba(101, 99, 255, 0.78);
}

@keyframes neonTitlePulse {
  0%,
  100% {
    filter: brightness(0.92);
    text-shadow:
      0 0 4px rgba(255, 255, 255, 0.8),
      0 0 11px rgba(99, 210, 255, 0.72),
      0 0 24px rgba(77, 121, 255, 0.52);
  }
  50% {
    filter: brightness(1.15);
    text-shadow:
      0 0 7px #fff,
      0 0 18px rgba(99, 224, 255, 1),
      0 0 38px rgba(91, 112, 255, 0.88);
  }
}

@keyframes neonSubtitlePulse {
  0%,
  100% {
    opacity: 0.82;
  }
  50% {
    opacity: 1;
  }
}

@keyframes neonCardPulse {
  0%,
  100% {
    border-color: rgba(102, 211, 255, 0.3);
    box-shadow:
      0 0 10px rgba(68, 179, 255, 0.14),
      inset 0 0 15px rgba(74, 111, 255, 0.06);
  }
  50% {
    border-color: rgba(151, 231, 255, 0.62);
    box-shadow:
      0 0 19px rgba(68, 179, 255, 0.34),
      inset 0 0 24px rgba(94, 111, 255, 0.12);
  }
}

@media (prefers-reduced-motion: reduce) {
  #web_bg.theme-crossfade.theme-crossfade-run::after {
    transition: none;
  }

  [data-theme='dark'] #site-title,
  [data-theme='dark'] #site-subtitle,
  [data-theme='dark'] #aside-content .card-info {
    animation: none !important;
  }
}