HTML and CSS Reference
Comments are text you can add to CSS to, well, comment! A browser ignores comments, so they aren't displayed
in a web page but they do appear in the CSS file that's downloaded to a user's computer. You may like to add com-
ments to keep notes about why you used a particular style, for example.
To let the browser know you are using a comment that it can ignore, use the following syntax:
/* Hi Mom. I made this web page! */
You should prefix a comment with a forward slash and an asterisk and suffix it with an asterisk followed by a for-
ward slash. Comments can be used either outside or within CSS rule sets.
You can also use comments for “commenting out” styles. If you added a style to a page but want to see the page
without that style for a moment, rather than delete the style, you can make it a comment, causing the browser to ig-
When a hex value is #000000 , it has no color, making it black, and at the opposite end of that range, #ffffff is
white. Your background color should now closer match the color of the background image, but how on earth do you
determine #f5f5f5 is a gray color? To get the exact color, you need to use a tool, often known as a color picker ;
see the sidebar “Color Pickers.”
To make writing hexadecimal values a little quicker, when a value has repeating characters (such as #ffffff ), you
can write #fff instead. Three character values are expanded to six by replicating each character. For example,
#fb0 expands to #ffbb00 .
Unfortunately, you can't shorten #f5f5f5 .
Many graphics editors come with color pickers (such as Adobe Photoshop and Fireworks). If this is something you
don't already have, here are some free ones you can use:
RGB (Integer Range)
RGB can also be specified via an integer range from 0 - 255 or 0 - 100%. Much like hex, the bottom of the range (0)
represents black, and the top (255/100%) is white.
To set the background to white, for example, you can use the following:
background-color: rgb(255, 255, 255);