/* ancientfit-frontend/css/mainScrollToTop.css */
#scrollToTopMainBtn {
  position: fixed;
  bottom: 30px;
  right: 30px;
  z-index: 9999;
  width: 60px;
  height: 60px;
  border: 1px solid rgba(255, 255, 255, 0.2); /* slightly darker border */
  border-radius: 50%;
  
  /* DARKER glassy effect */
  background: linear-gradient(135deg, rgba(20, 20, 25, 0.6), rgba(30, 30, 35, 0.3));
  backdrop-filter: blur(25px);
  -webkit-backdrop-filter: blur(25px);

  color: #00bfff; /* blue arrow */
  font-size: 28px;
  font-weight: bold;
  text-align: center;
  line-height: 60px;
  cursor: pointer;
  display: none;

  box-shadow:
    0 0 12px rgba(0, 191, 255, 0.4),
    0 5px 25px rgba(0, 0, 0, 0.5),
    inset 0 0 8px rgba(255, 255, 255, 0.15);

  text-shadow: 0 0 8px rgba(0, 191, 255, 0.8);
  transition: all 0.4s ease;
  animation: pulse 2.5s infinite;
  overflow: hidden;
}

/* Slightly stronger pulse for darker glass */
@keyframes pulse {
  0% {
    box-shadow:
      0 0 12px rgba(0,191,255,0.4),
      0 5px 25px rgba(0,0,0,0.5),
      inset 0 0 8px rgba(255,255,255,0.15);
  }
  50% {
    box-shadow:
      0 0 18px rgba(0,191,255,0.6),
      0 6px 28px rgba(0,0,0,0.55),
      inset 0 0 10px rgba(255,255,255,0.2);
  }
  100% {
    box-shadow:
      0 0 12px rgba(0,191,255,0.4),
      0 5px 25px rgba(0,0,0,0.5),
      inset 0 0 8px rgba(255,255,255,0.15);
  }
}

/* Hover effect with stronger glow */
#scrollToTopMainBtn:hover {
  background: linear-gradient(135deg, rgba(25, 25, 30, 0.7), rgba(35, 35, 40, 0.4));
  transform: scale(1.1);
  box-shadow:
    0 0 20px rgba(0, 191, 255, 0.7),
    0 6px 30px rgba(0,0,0,0.6),
    inset 0 0 12px rgba(255,255,255,0.25);
}

#scrollToTopMainBtn:hover::before {
  animation: particle-spark 1s infinite linear;
  background: radial-gradient(circle, rgba(0,191,255,0.4) 20%, transparent 70%);
  opacity: 0.8;
}

@keyframes particle-spark {
  0% {
    transform: scale(1) translateY(0);
    opacity: 0.7;
  }
  50% {
    transform: scale(1.2) translateY(-10px);
    opacity: 0.4;
  }
  100% {
    transform: scale(1) translateY(0);
    opacity: 0.7;
  }
}