Css box model

-- By default in the CSS box model, the width and height you set to an element is applied only to the element's content.

---The width and height properties include the content, but they do not include. the padding, border, or margin.

box-sizing:content-box; /defaullt val

box-sizing: border-box; /best for developing layouts

'*' is a universal selector in and applies to all HTML elements

speficity in css inline>id>class>type>universal