Design to drift. Elements on our page can cause users to get confused while reading or to unintentionally click on the wrong element. To calculate the cls value, google measures changes to the page layout. It only takes into account movements of elements that happen unexpectedly, excluding intentional changes through user interactions. Google not only looks at how many items are moved and how often, but also records how far they are moved. With all these parameters the cumulative layout shift is calculated. What tools can we use to measure the core web vitals?