export function labelTextColor(hex: string): string { const r = parseInt(hex.slice(1, 3), 16); const g = parseInt(hex.slice(3, 5), 16); const b = parseInt(hex.slice(5, 7), 16); const luminance = (0.299 * r + 0.587 * g + 0.114 * b) / 255; return luminance > 0.5 ? "#000000" : "#ffffff"; }