src/vs/base/browser/ui/menu/menu.ts/BaseMenuActionViewItem/applyStyle
class BaseMenuActionViewItem:	protected applyStyle(): void {
		if (!this.menuStyle) {
			return;
		}

		const isSelected = this.element && this.element.classList.contains('focused');
		const fgColor = isSelected && this.menuStyle.selectionForegroundColor ? this.menuStyle.selectionForegroundColor : this.menuStyle.foregroundColor;
		const bgColor = isSelected && this.menuStyle.selectionBackgroundColor ? this.menuStyle.selectionBackgroundColor : undefined;
		const border = isSelected && this.menuStyle.selectionBorderColor ? `thin solid ${this.menuStyle.selectionBorderColor}` : '';

		if (this.item) {
			this.item.style.color = fgColor ? fgColor.toString() : '';
			this.item.style.backgroundColor = bgColor ? bgColor.toString() : '';
		}

		if (this.check) {
			this.check.style.color = fgColor ? fgColor.toString() : '';
		}

		if (this.container) {
			this.container.style.border = border;
		}
	}