Selectors level 3, - Namespaces and - Media queries. CSS - Level 3 - Font properties, - Text attributes. - Alignment of text, tables, images. - Colours of text and backgrounds, - Spacing of words, letters and lines, Margins, borders, padding and positioning CSS - Level 1 ... CSS - Level 4 - z-index, - Position: Absolute, relative and fixed - Float - Tipos de dispay: flexbox, grid, table CSS - Level 2 1998-1999 2011