This sets a quarter-inch of blank space on each side of an H1 element. In Figure 7-6, this is represented using dashed lines which are included for illustrative purposes. These lines would not actually appear in a web browser.
margin can accept any length measure, whether in pixels, inches, millimeters, or ems. However, the default value for margin is effectively 0 (zero), which means that if you don't declare a value, then by default,
Index
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| D. CSS Suport Chart |  | Colophon |
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influence over the rest of the document.Of course, when an element is floated, other content "flowsaround" it. This is familiar behavior with floated images, butthe same is true if you float a paragraph, for example. In Figure 7-64, we can see this effect (a margin has beenadded to make the situation more clear):
P.aside {float: left; width: 5em; margin: 1em;}
If the value 500 is unassigned, it is given the same font weight as that assigned to 400.
If 300 is unassigned, it is given the next variant lighter than 400. If no lighter variant is available, 300 is assigned the same variant as 400. In this case, it will usually be "Normal" or "Medium." This method is also used for 200 and 100.the appearance of the border, although it does do that, but becausewithout a style there would be no border at all.
There are nine distinct styles for theproperty border-style defined in CSS1, includingthe default value of none. They are demonstratedin Figure 7-29.
TIP