Acquia Cohesion renames to Site Studio from version 6.2. Tell me more.
We recommend using decimals e.g. 1.3 as this makes the line height relate to your font size.
You have to upload a JSON file to provide the index of the icons within your chosen icon font.
It depends on the font you are using. If you have individual files for each font, you should upload zip files for each weight.
The Youtube video embed is responsive so it should expand to the width of its parent. If you do need to set a width you can apply the Width CSS property through the Style Builder.
The WYSIWYG (ckeditor) adds a paragraph tag around the text within the block quote. This causes it to inherit the text size of your paragraph base style.
Custom styles are CSS styles for classes.