message: perf: use inline style instead of getComputedStyle
diff: @@ -10,13 +10,24 @@ export function addUnit(value?: string | number): string | undefined {
  return isNumeric(value) ? `${value}px` : value;
  }
  -function convertRem(value: string) {
  - const rootStyle = window.getComputedStyle(document.documentElement);
  - const rootFontSize = parseFloat(rootStyle.fontSize);
  +// cache
  +let rootFontSize: number;
  - value = value.replace(/rem/g, '');
  +function getRootFontSize() {
  + if (!rootFontSize) {
  + const doc = document.documentElement;
  + const fontSize =
  + doc.style.fontSize || window.getComputedStyle(doc).fontSize;
  +
  + rootFontSize = parseFloat(fontSize);
  + }
  - return +value * rootFontSize;
  + return rootFontSize;
  +}
  +
  +function convertRem(value: string) {
  + value = value.replace(/rem/g, '');
  + return +value * getRootFontSize();
  }
  export function unitToPx(value: string | number): number {
  