/* ============================================
   STORY FORGE — Buttons & Interactive Controls
   ============================================ */

/* ---- Base ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 10px 20px;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 600;
  line-height: 1;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  white-space: nowrap;
  user-select: none;
  text-decoration: none;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* ---- Variants ---- */
.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  color: white;
  box-shadow: 0 4px 15px var(--accent-glow-sm), inset 0 1px 0 rgba(255,255,255,0.15);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--accent-glow), inset 0 1px 0 rgba(255,255,255,0.2);
  background: linear-gradient(135deg, #8b46ff, #b566ff);
}
.btn-primary:active { transform: translateY(0); box-shadow: 0 2px 10px var(--accent-glow-sm); }

.btn-secondary {
  background: var(--bg-glass);
  color: var(--text-primary);
  border: 1px solid var(--border-medium);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}
.btn-secondary:hover {
  background: var(--bg-glass-md);
  border-color: var(--border-bright);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid transparent;
}
.btn-ghost:hover {
  color: var(--text-primary);
  background: var(--bg-glass);
  border-color: var(--border-subtle);
}

.btn-danger {
  background: rgba(244, 63, 94, 0.15);
  color: var(--accent-rose);
  border: 1px solid rgba(244, 63, 94, 0.3);
}
.btn-danger:hover {
  background: rgba(244, 63, 94, 0.25);
  border-color: var(--accent-rose);
}

/* ---- Sizes ---- */
.btn-icon    { width: 38px; height: 38px; padding: 0; border-radius: var(--radius-md); }
.btn-icon-sm { width: 30px; height: 30px; padding: 0; border-radius: var(--radius-sm); }
.btn-lg { padding: 14px 28px; font-size: var(--text-base); border-radius: var(--radius-lg); }
.btn-sm { padding: 6px 12px; font-size: var(--text-xs); }

/* ---- Loading spinner ---- */
.btn.loading { pointer-events: none; opacity: 0.8; }
.btn.loading::after {
  content: '';
  width: 14px; height: 14px;
  border: 2px solid transparent;
  border-top-color: currentColor;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
  margin-left: var(--space-2);
}

/* ---- Misc states ---- */
.btn-active { box-shadow: inset 0 0 0 2px currentColor; }

/* ---- Tabs ---- */
.tabs {
  display: flex;
  gap: 2px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 4px;
}
.tab-btn {
  flex: 1;
  padding: 8px 16px;
  background: transparent;
  border: none;
  border-radius: var(--radius-sm);
  color: var(--text-dim);
  font-size: var(--text-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-sans);
}
.tab-btn:hover { color: var(--text-secondary); background: var(--bg-glass); }
.tab-btn.active {
  background: var(--accent-primary);
  color: white;
  box-shadow: 0 2px 8px var(--accent-glow-sm);
}

/* ---- Nav active ---- */
.nav-link.active {
  color: var(--text-primary);
  background: rgba(124, 58, 237, 0.12);
  position: relative;
}
.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -1px; left: 50%;
  transform: translateX(-50%);
  width: 16px; height: 2px;
  background: var(--accent-primary);
  border-radius: var(--radius-full);
}