CSS relative positioning

Four modes of positioning: static,relative,absolute,fixed

Positioning four positions: Left,right,top,bottom

Positioning properties: Position, there are four status values

1.static: Static positioning, arranged in the order of elements in the document flow, which is the default value, four positions are invalid

2.relative: Relative positioning, the element is positioned relative to its position in the document stream, four positions are valid

3.absolute: Absolute positioning, the element is positioned relative to its location parent, out of the document stream, four positions valid

4.fixed: Fixed positioning, similar to the absolute positioning class, also out of the document flow, the position of elements on the page fixed, do not scroll with the page, four positions valid

<! DOCTYPE html>