/* ── Button component ───────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-5);
  height: 36px;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  font-family: var(--font-family);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  line-height: 1;
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  transition:
    background var(--transition-fast),
    border-color var(--transition-fast),
    color var(--transition-fast),
    box-shadow var(--transition-fast);
  user-select: none;
}
.btn svg { width: 15px; height: 15px; stroke: currentColor; flex-shrink: 0; }

.btn:focus-visible {
  outline: 2px solid var(--clr-primary);
  outline-offset: 2px;
}
.btn:disabled { opacity: 0.45; cursor: not-allowed; pointer-events: none; }

/* Primary */
.btn--primary {
  background: var(--clr-primary);
  color: #fff;
}
.btn--primary:hover { background: var(--clr-primary-hover); }
.btn--primary:active { background: hsl(250, 70%, 42%); }

/* Secondary (outlined) */
.btn--secondary {
  background: var(--clr-surface);
  color: var(--clr-text-primary);
  border-color: var(--clr-border);
}
.btn--secondary:hover { background: var(--clr-surface-2); }

/* Ghost */
.btn--ghost {
  background: transparent;
  color: var(--clr-text-secondary);
  border-color: transparent;
}
.btn--ghost:hover { background: var(--clr-surface-2); color: var(--clr-text-primary); }

/* Danger */
.btn--danger {
  background: var(--clr-danger);
  color: #fff;
}
.btn--danger:hover { background: hsl(4, 72%, 48%); }

/* Danger outline */
.btn--danger-outline {
  background: transparent;
  color: var(--clr-danger);
  border-color: var(--clr-danger);
}
.btn--danger-outline:hover { background: var(--clr-danger-light); }

/* Sizes */
.btn--sm { height: 30px; padding: 0 var(--sp-3); font-size: var(--text-xs); gap: var(--sp-1); }
.btn--lg { height: 44px; padding: 0 var(--sp-8); font-size: var(--text-md); }

/* Icon-only */
.btn--icon {
  width: 36px; height: 36px;
  padding: 0;
  border-radius: var(--radius-md);
}
.btn--icon.btn--sm { width: 30px; height: 30px; }

/* Loading state */
.btn.loading { position: relative; color: transparent; pointer-events: none; }
.btn.loading::after {
  content: '';
  position: absolute;
  width: 14px; height: 14px;
  border: 2px solid rgba(255,255,255,0.4);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}