1 .css3 box model :
① margin Margin:
Margin-top，Margin-right，Margin-bottom，Margin-left
② Border Border:
Border-width
Border-style: solid solid border, dotted dotted border, Double double border
Border-color
③ the Padding Padding : receiving length and percentage, but does not accept negative.
Padding-top，Padding-right，Padding-bottom，Padding-left
Padding * while setting four margins
padding ** while setting down, right and left margins
padding *** simultaneously set, left and bottom margins
Padding **** while setting up, right, down, left margin
④ margins of the merger:
When the two vertical margins meet, they will form a margins.
The combined height equal to the margins of the larger of the two combined height of the outer margin of the occurrence.
⑤ overflow processing:
Overflow If the contents spilled, whether cropping edges of the content.
Overflow-x If the contents spilled, whether on the left and right edge of the content of the crop.
Overflow-y If the contents spilled, whether the upper and lower edge of the content of the crop.
Visible is not cutting, the contents will be displayed outside the box.
Hidden cutting, does not provide a scrolling mechanism.
Scroll crop, providing scrolling mechanism.
auto overflow, it provides scrolling mechanism.
