CSS Comments

Many times you may need to put additional comments in your style sheet blocks. So it is very easy to comment any part in style sheet. You simple put your comments inside /*… this is a comment in style sheet….. */

You can use /*….. */ to comment multi-line blocks in similar way you do in C and C++ programming languages.


/* This is an external style sheet file */

h1,h2,h3 {

color: #36C;

font-weight : normal;

letter-spacing: .4em;

margin-bottom: lem;

text-transform: lowercase;


/* end of style rules, */


CSS Units

Before we start actual exercise, I would like to give a brief  idea about the CSS measurement units.

CSS supports a number of measurements including absolute units such as inches, centimeters, points, and so on, as well as relative measures such as percentages and em units. You need these values while specifying various measurements in your style rules e.g border = “1px solid red”

we have listed out all the CSS measurement units along with proper Examples


%Defines a measurement as a percentage relative to another value, typically an enclosing elementp{font-size:16pt;line-height:125%}
cmDefines a measurement in centimetersdiv {margin-bottom:2cm}
EmA relative measurement for the height of a font in em spaces. Because an em unit is equivalent to the size of a given font, if you assign a font to 12pt, each “em” unit would be 12pt; thus, 2em would be 24ptp{letter-spacing:7em;}
ExThis value defines a measurement relative to a font’s X-height. The x-height is determined by the height of the font’s lowercase letter X.p{font-size:24pt;line-height:3ex;}
InDefines a measurement in inches.P{word-spacing: 15in;}
mmDefines a measurement in millimeterp{word-spacing:15mm;}
pcDefines a measurement in picas, A pica is equivalent to 12 points; thus there are 6 picas per inchp{font-size:20c;}
ptDefines a measurement in points. A point is defined as 1/72nd of an inchbody{font-size:18pt;}
pxDefines a measurement in screen pixels.p{padding:25px;}