Full analysis of web page elements

Relative Length Units
em
Description: Relative length unit. Relative to the font size of the text within the current object.
If the font size of the text in the current line is not set manually, it is relative to the browser's default font size.
Example:
div { font-size : 1.2em; }
ex
Description: Relative length unit. Relative to the height of the "x" character. This height is usually half the font size.
If the font size of the inline text is not set manually, it is relative to the browser's default font size.
Example:
div { font-size : 1.2ex; }
px
Description: Relative length unit. Pixel.
Pixels are relative to the monitor screen resolution. For example, the resolution used by WONDOWS users is generally 96 pixels per inch. The resolution used by MAC users is generally 72 pixels per inch.
Example:
div { font-size : 12px; }

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Absolute Length Units
pt
illustrate:
Absolute length unit. Point.
1in = 2.54cm = 25.4mm = 72pt = 6pc
Example:
div { font-size : 9pt; }
pc
illustrate:
Absolute length unit. Pica. It is equivalent to the size of my country's new No. 4 lead type.
1in = 2.54cm = 25.4mm = 72pt = 6pc
Example:
div { font-size : 0.75pc; }
in
illustrate:
Absolute length unit. Inch.
1in = 2.54cm = 25.4mm = 72pt = 6pc
Example:
div { font-size : 0.13in; }
cm
illustrate:
Absolute length unit. Centimeter (Centimeter).
1in = 2.54cm = 25.4mm = 72pt = 6pc
Example:
div { font-size : 0.33cm; }
mm
illustrate:
Absolute length unit. Millimeter.
1in = 2.54cm = 25.4mm = 72pt = 6pc
Example:
div { font-size : 3.3mm; }

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Color Units Reference
#RRGGBB
parameter:
RR:

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