.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 18px;
  font-family: var(--font-base);
  font-size: 13px;
  letter-spacing: 0.06em;
  font-weight: 400;
  border: 1px solid transparent;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  white-space: nowrap;
  text-decoration: none;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
}

.btn--primary:hover {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
}

.btn--ghost {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn--ghost:hover {
  background: var(--color-bg);
  border-color: var(--color-text-muted);
}

.btn--danger {
  background: transparent;
  color: var(--color-danger);
  border-color: var(--color-danger);
}

.btn--danger:hover {
  background: var(--color-danger);
  color: var(--color-text-inverse);
}

.btn--sm {
  padding: 5px 12px;
  font-size: 12px;
}

.btn--full {
  width: 100%;
}

.btn--active {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn:empty {
  display: none;
}

.btn--loading {
  pointer-events: none;
  opacity: 0.6;
  position: relative;
}

.btn--loading::after {
  content: '';
  width: 14px;
  height: 14px;
  border: 2px solid currentColor;
  border-right-color: transparent;
  border-radius: 50%;
  animation: btn-spin 0.5s linear infinite;
  margin-left: 6px;
}

@keyframes btn-spin {
  to { transform: rotate(360deg); }
}