Right-click anything on the page to edit it where it is.
The menu is the element's styles as blocks: the element itself on top, then every style it gets from the site. Each block edits one thing, and says how many elements it reaches.
Every property has the right control for the job, such as a size field, color picker, or list of options.
The first block is the selected element, and a change there stays with it. The blocks below are the styles it uses. A change in one of them reaches every element with that style, and the number by its name says how many.
The cross on a block takes that class or id off the element.
Every block ends with a row for a new property. Start typing in the block you want to change, and the properties that match show up right under it. Press Enter to take the first one, or choose another.
A property goes where you typed it, and nowhere else.
The element's block always ends with a note. Write what should change in your own words, and the agent that builds your edits reads it there.
The last row adds a class or an id to the element. Start typing, then choose a suggestion or press Enter to create it. It becomes a block of its own, ready for its first property.
Turn edit mode on and right-click anything you see.