message: simplify getSizeXClassName
diff: @@ -4,9 +4,5 @@ export function getSizeXClassName(
  base: string,
  sizeX?: AdaptivityProps["sizeX"]
  ): string {
  - if (!sizeX) {
  - return `${base}--sizeX-none`;
  - }
  -
  - return `${base}--sizeX-${sizeX}`;
  + return `${base}--sizeX-${sizeX ?? "none"}`;
  }
  