/* SFX mute toggle — sits bottom-left, doesn't conflict with .scroll-top */
.sfx-toggle {
  position: fixed;
  left: 1.25rem;
  bottom: 1.25rem;
  z-index: 91;
  width: 42px;
  height: 42px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: rgba(8, 18, 28, .85);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(0, 229, 240, .35);
  border-radius: 999px;
  color: #00e5f0;
  cursor: pointer;
  transition: all .2s ease;
  box-shadow: 0 0 16px rgba(0, 229, 240, .12);
}
.sfx-toggle:hover {
  border-color: rgba(0, 229, 240, .85);
  box-shadow: 0 0 22px rgba(0, 229, 240, .35);
  transform: translateY(-2px);
}
.sfx-toggle.muted {
  color: #ff7a1f;
  border-color: rgba(255, 122, 31, .45);
  box-shadow: 0 0 14px rgba(255, 122, 31, .18);
}
.sfx-toggle.muted:hover {
  border-color: rgba(255, 122, 31, .85);
  box-shadow: 0 0 22px rgba(255, 122, 31, .4);
}