Styling
Styling with CSS can be done in the HTML without the need of a style sheet just by using the style tag. This tag notifies the browser to start interpreting the code as CSS styles rather than HTML text. Just like all other tags, once the style tag closes the code would no longer be interpreted as CSS style but will return to be HTML.
Contextual Selectors
Location based selectors can be used to create declarations for multiple tags. By using article p {}, all the paragraph tags in the article will be affected, but no other p tags outside of articles will be affected. This can also be used with multiple tags that would need the same effect, such as article h1, h2 {} both h1 and h2 will have the declaration affect them.
Tagging child
Child tags are able to be selected, it not only must be the parents, which has been learned so far. Siblings can also be located similarly with specialized selectors; it is all about being specific. Selector tags can be used as tag1 + tag2 and child can be used with tag1 > tag2.