tailieunhanh - Learning Web Design Third Edition- P26

Learning Web Design Third Edition- P26:Everything you need to know to create professional web sites is right here. Learning Web Design starts from the beginning defining how the Web and web pages work and builds from there. By the end of the book, you'll have the skills to create multi-column CSS layouts with optimized graphic files, and you'll know how to get your pages up on the Web. | Specifying Color Values Figure 13-4. If you don t have an image editing program you could pick a color from the charts provided at www. . RGB is one of four color models provided in the Color Picker the others are HSB Lab and CMYK . The RGB values listed here The same RGB values ready to be inserted in a style sheet Figure 13-3. The Color Picker in Adobe Photoshop provides the RGB values for a selected pixel color. Another cool tool for finding RGB values is Colorzilla a free extension to the Firefox browser that gives you the values for any pixel color in the browser window among many other features . Download it at . com firefox colorzilla . If you don t have these programs you could pick a color from a chart of colors such as the ones provided on the web site for this book Figure 13-4 . Between the Color Names chart colornames. html and the Web Palette Colors chart there are more than 300 color samples. If you see something you like copy down the RGB values listed. Writing RGB values in style sheets CSS allows RGB color values to be specified in a number of formats. Going back to that pleasant lavender we could add it to a style sheet by listing each value on a scale from 0 to 255. color rgb 200 178 230 AT A GLANCE Specifying RGB Values There are four formats for providing RGB values in CSS rgb 255 255 255 rgb 100 100 100 FFFFFF FFF All of these examples specify white. You can also list them as percentage values although that is less common. color rgb 78 70 90 Or you can provide the web-ready version that we saw in the Color Picker. These six digits represent the same three RGB values except they have been converted into hexadecimal or hex for short values. I ll explain the hexadecimal system in the next section. Note that hex RGB values are preceded by the symbol and do not require the rgb notation shown above. color C8B2E6 There is one last shor thand way to .