If text-indent is set to a percentage value, which width is it using for the calculation?

Another problem related to the rewrite of my Textarea Line Count plugin (<-- shameless plug)

开发者_JS百科

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The text-indent property of CSS provides white space preceding the first line of text. Possible values include measurements in px, em, pt, etc. but also as a percentage %.

So, let's say you specify that your text-area should have: text-indent: 30%. But, 30% of which width is used to perform this calculation? Is it the outer width or the inner width? In other words, are any of the following included in the width:

• Border
• Margin
• Padding

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30% the width of the parent. It will always inherit the parent width for percentage.

Padding and border add to the parents width, whereas margin does not, ie

#example {width: 200px; padding: 0 5px; border: 1px solid #000;}

would be a total width of 212px.

Margin is a positiong tool and only affects what space should be between objects.

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I've figured it out. Border is not included in the calculation, since this technically isn't included in the element's width. Only inner width is measured; no border, padding, margin, etc.