.theme-toggle {
  position: fixed;
  right: 18px;
  bottom: 24px;
  width: 52px;
  height: 52px;
  border-radius: 10px;
  border: 1px solid var(--border-default);
  background: var(--bg-surface);
  color: var(--text-primary);
  z-index: 1040;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.18);
}
.theme-toggle i {
  font-size: 23px;
  line-height: 1;
}
.theme-toggle:hover {
  border-color: var(--accent-border);
  color: var(--accent);
}

.scroll-top-btn {
  position: fixed;
  right: 18px;
  width: 52px;
  height: 52px;
  border-radius: 10px;
  border: 1px solid var(--border-default);
  background: var(--bg-surface);
  color: var(--text-primary);
  z-index: 1039;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.18);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .25s ease, visibility .25s ease, transform .25s ease, border-color .2s, color .2s;
  cursor: pointer;
  padding: 0;
  border-style: solid;
  outline: none;
}
.scroll-top-btn i {
  font-size: 23px;
  line-height: 1;
}
.scroll-top-btn:hover {
  border-color: var(--accent-border);
  color: var(--accent);
}
.scroll-top-btn.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

@media (max-width: 991.98px) {
  .theme-toggle {
    right: 14px;
    bottom: 20px;
    width: 48px;
    height: 48px;
  }
  .theme-toggle i {
    font-size: 21px;
  }
  .scroll-top-btn {
    right: 14px;
    width: 48px;
    height: 48px;
  }
  .scroll-top-btn i {
    font-size: 21px;
  }
}