.random-backdrop {
  position: fixed;
  inset: 0;
  z-index: 0; /* 低于 #root (z-index: 1)，保证监控卡片与顶栏在上层 */
  pointer-events: none;
  overflow: hidden;
}

/* 略放大并外扩，减轻模糊后边缘露底 */
.random-backdrop__image {
  position: absolute;
  inset: -16px;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  transform: scale(1.04);
  /* 需求「10%」按常用约定映射为 10px 半径（CSS blur 无百分比） */
  filter: blur(10px);
  -webkit-filter: blur(10px);
}

.random-backdrop__fallback {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(120% 80% at 20% 20%, rgba(252, 231, 243, 0.95) 0%, transparent 55%),
    radial-gradient(100% 90% at 80% 30%, rgba(224, 231, 255, 0.9) 0%, transparent 50%),
    linear-gradient(160deg, #fdf4ff 0%, #e0f2fe 45%, #fce7f3 100%);
}
