The concept of layered and inheritance
Text general properties of the class are inherited, namely CSS properties of an element is passed to the internal nested elements. An element may have one or more sources of style, the property when the property conflict, will be displayed after loading according to the order and the right to decide major small stack.
Priority selector
| Row | id | class | element | |
| Row | 1 | 0 | 0 | 0 |
| id | 0 | 1 | 0 | 0 |
| class, attributes, pseudo-class |
0 | 0 | 1 | 0 |
| Elements, pseudo-elements | 0 | 0 | 0 | 1 |
| Tsuhaifu * | 0 | 0 | 0 | 0 |
| ！important | highest | |||
Box Model
margin
|
Positioning ( position )
relative: to make the absolute father, and with the z-index (the default is auto, auto 0 is calculated, but the auto and z-index: 0 on the different values at the higher.)
absolute: a layer from the document flow, to find a parent element in a first positioning element (position is that there is not a static element positioning)
fixed: this will be fixed on the page, drag up and down your pages are the same, microblogging back to the top of the inside is so used
sticky: not out of the page when it is normal relative, it is fixed at the top
Normal flow
Conventional flow, document flow, ordinary document flow, regular document flow
All the elements, by default, are all conventional flow layout
General rule: block own line box, the horizontal line are sequentially arranged in the cartridge
Comprising a block (containing block): Each box has its containing block, decision block comprising a box arrangement region.
The vast majority of cases: a block containing box, the contents of the cartridge to its parent element