Some people say that the XHTML webpage is a structured webpage that encapsulates content information through Div like a box. In a visible structure, each element is displayed as a two-dimensional plane. The diagram is as follows:
CSS 2D graphic
The following is a detailed breakdown:
The inmost white area is the content information display area, which can be an image or text, while the content display area is controlled by the height and width; the Content Rendering area is surrounded by the outer rectangle padding (gray area). This layer cannot be set with color, but is the background color of the transparent content, followed by the border of the CSS element (Border) (Red area), this is the border can set the width and color, solid line, dotted line and other styles; the white area of the outermost layer of the dotted line and the red range is the border distance (margin ), the box spacing adjacent to the exterior of the element is also colorless and transparent, and there is no color setting style.