passwd/pages/components/background/background.wxss

.bg {
  position: fixed;
  flex-direction: column;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-repeat: no-repeat #000;
  background-size: cover;
  background-position: left;
  z-index: -1;
}

.bg image{
  width: 100%;
  height: 100%;
}