*{
  margin: 0;
  padding: 0;
  box-sizing:border-box ;
  font-family: sans-serif;
}

.banner{
  position: relative;
  width: 100%;
  height: 100vh;
  background-image: url(pexels-p.webp);
  background-position: bottom;
  background-size: cover;
  display: flex;
  justify-content: center;
  align-items: center;
  color: aliceblue;
  animation: siam 2s;
  overflow: hidden; /* fog control */
}

/* Clouds Layer */
.banner .clouds{
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  pointer-events: none;
}

.banner .clouds img{
  position: absolute;
  bottom: 0;
  max-width: 100%;
  animation: tofu calc(3s*var(--i)) linear infinite;
}

@keyframes tofu{
  0%{
    opacity: 0;
    transform: scale(1);
  }
  27%,75%{
    opacity: 1;
  }
  100%{
    opacity: 0;
    transform: scale(3);
  }
}

/* 🌫️ Fog Layer (div instead of ::after) */
.fog{
  position: absolute;
  top: 0;
  left: 0;
  width: 150%;
  height: 150%;
  
  filter: blur(10px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.5s ease;
}

/* Fog appears only on hover */
.banner:hover .fog{
  opacity: 0.6;
}