elements (nav/section/article/aside/div)

https://www.w3.org/TR/html5/

https://www.w3.org/TR/html5/sections.html#the-nav-element

https://www.w3.org/TR/html5/sections.html#the-section-element

https://www.w3.org/TR/html5/sections.html#the-article-element

https://www.w3.org/TR/html5/grouping-content.html#the-div-element

https://www.w3.org/TR/html5/sections.html#the-header-element

https://www.w3.org/TR/html5/sections.html#the-footer-element

https://www.w3.org/TR/html5/grouping-content.html#the-main-element

https://www.w3.org/TR/wai-aria/
https://www.w3.org/TR/wai-aria/#landmark_roles

https://www.w3.org/TR/html-aria/


https://www.w3schools.com/html/html5_semantic_elements.asp