You want to be the best, you MUST put the long yards in! Nothing comes easy in life so stop wishing and start DOING! So many people would rather bitch and moan than help themselves. Dont be one of those negative drainers, start today, make a small change and keep going forwards with this attitude!
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<percentage>

The <percentage> CSS data type represents a percentage value. It is often used to define a size as relative to an element's parent object. Numerous properties can use percentages, such as width, height, margin, padding, and font-size.
<percentage> css reference