/* 会动的小动物（小鹅 / 小鸭 / 飞鸟） */
.critters{position:absolute;inset:0;z-index:-1;pointer-events:none;overflow:hidden}
.critter{position:absolute;filter:drop-shadow(0 5px 8px rgba(90,70,160,.16));opacity:.94}
.critter svg{display:block;width:100%;height:100%}

.c-duck{left:12px;bottom:100px;width:58px;animation:waddle 2.5s ease-in-out infinite}
.c-goose{right:14px;bottom:154px;width:62px;animation:bob 3.2s ease-in-out infinite}
.c-duck2{right:38px;bottom:80px;width:46px;animation:waddle 3.4s ease-in-out infinite reverse;opacity:.84}
.c-bird{left:21%;top:152px;width:32px;animation:floaty 7s ease-in-out infinite}
.c-bird2{right:17%;top:236px;width:26px;animation:floaty 9s ease-in-out infinite reverse;opacity:.72}

@keyframes waddle{
  0%,100%{transform:translateY(0) rotate(-5deg)}
  50%{transform:translateY(-4px) rotate(5deg)}
}
@keyframes bob{
  0%,100%{transform:translateY(0) rotate(2deg)}
  50%{transform:translateY(-9px) rotate(-2deg)}
}
@keyframes floaty{
  0%,100%{transform:translate(0,0) rotate(-4deg)}
  25%{transform:translate(12px,-14px) rotate(2deg)}
  50%{transform:translate(-5px,-22px) rotate(-2deg)}
  75%{transform:translate(-13px,-7px) rotate(4deg)}
}