Use CSS and HTML to write a layout of Header, Left side bar, and Main content layout, header and main content width needs to change with browser width and needs to have conformable margin and padding, and background color should be red, green, blue, Should work on Safari, Chrome, Firefox, IE 6, 7, 8
用CSS和HTML写出“品”字型布局,要求上部标头和右下侧主体内容的宽度随浏览器变化而变化,背景上,左,右分别为红,绿,兰,在Safari,Chrome,Firefox, IE6,7,8上面可以正常显示