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can anyone help me by explaining widths, padding, margins & how to give "%", and "em" in it clearly tq

. widths . heights . margins . padding

Hello,

em is a relative size unit, to calculate the em size, just use the following formula: em = pixels / 16 (20px / 16 = 1.25 em)

% is flexible value for html elements. (if you have set your container width 100% and in container you have two elements width 50% it's mean in every browser size elements has same size)

width is css property for html element and can use for many html elements.

height is css property sets the height for html element.

margin is css property set the size of the white space outside border of html element.

padding is css property set the size of the white space inside border of html element.

An em is a relative unit of measurement determined by the element's font-size.

body { font-size: 1em; // here, one em is 16 pixels by default }

If you set the margin, the space outside a container, and the padding, the space inside the container, to 1em, then there will be 16 pixels of space inside and outside that container. Going back and changing the font-size on the body will adjust every element on the page to the new size, scaling up or down accordingly. The tricky part comes in when you adjust the font-size within a container, which now determines that container's em size.

A percentage is always relative to its container. A container set to 80%, always takes up 80% of the available width. So the actual width of that container will scale up and down according the size of the viewport.

Setting your font-sizes in % will be relative to the containing block's font-size.

So, font-size: 120% will be 16 x 1.2 = 19.2 pixels only if the container's font-size hasn't been set. If you had changed the font-size on the body element to be 10px, then your calculation would be 10 x 1.2 = 12

Don't know if that helps.