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Archive for the ‘CSS’ Category

Many times we need to center align a DIV inside another div. If we know the width of the inner DIV in before hand it is really simple, we can just add the width, margins to 0px and auto and that’s it:

div.inner {
	margin:0px auto;

BUT, things may be more complicated if we don’t know the width of the inner DIV. In this case we need use a different type of display for the DIV (inline-block) and make sure that the outer div text-aligns everything to the center:

div.outer {
	text-align: center;
div.inner {
	display: inline-block;

The reason to this is that DIVs are by default display: block. This kind of display expands to the entire width except if we specify a fixed width but in this case, margin:0px auto. The inline-block display wraps its size around the its contents and allows to be aligned as text inside a div.

Note: Since IE7 doesn't understand the inline-block property, it will be needed to make a small hack to the inner div class for IE7 to work properly:

div.inner {
	display: inline-block;
	zoom: 1;
	*display: inline; #this will be ignored by all browsers except IE


!important declared after a CSS directive ensures that directive is applied preferred over other styles for the same locator no matter if the former is preceding the later or not.


if you are combining several CSS files in a webpage you may need to have to define two or more different styles for the same locator. For these cases, by using the rule !important you can ensure that style is applied over other conflicting styles for the same element/s.


Here is a simple example to ilustrate how to use this rule:

p { color: #ff0000 !important; }
p { color: #000000; }

In this example all the <p> elements affected by this stylesheet will have a red color for the text inside instead of black.

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