Focus Mode
Focus mode is a mode in which one component is emphasized over the other components. This is a state that can be reached in 3 ways: when the user clicks on an element with the mouse, when he navigates to it using the keyboard or when there is a script that set an element to the focus state.
When a user navigates with the keyboard using the TAB button it sets the focus on elements hierarchically according to how they appear in the web page’s DOM.