/* ============================================================
   FutureTools — Scroll-to-Top Button
   ============================================================ */

.ft-scroll-nav {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s cubic-bezier(0.4,0,0.2,1),
              visibility 0.3s,
              transform 0.3s cubic-bezier(0.4,0,0.2,1);
}

.ft-scroll-nav.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.ft-scroll-btn {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #fff;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 0.85rem;
  box-shadow: 0 4px 15px rgba(79,70,229,0.35);
  transition: background 0.25s, transform 0.25s, box-shadow 0.25s;
}

.ft-scroll-btn:hover {
  background: var(--color-secondary);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(6,182,212,0.45);
}

.ft-scroll-btn:active { transform: translateY(1px); }

/* Hide when AI panel is open */
.ft-ai-panel.open ~ .ft-scroll-nav {
  opacity: 0;
  pointer-events: none;
}

@media (max-width: 768px) {
  .ft-scroll-nav { right: 1.25rem; bottom: 1.25rem; }
  .ft-scroll-btn { width: 38px; height: 38px; font-size: 0.8rem; }
}

@media (max-width: 480px) {
  .ft-scroll-nav { right: 1rem; bottom: 1rem; }
  .ft-scroll-btn { width: 36px; height: 36px; font-size: 0.75rem; }
}

@media (prefers-reduced-motion: reduce) {
  .ft-scroll-nav, .ft-scroll-btn { transition: none; }
}