做网页设计时经常要用到各种形状的图形，对于规则的图形很简单，但是对于不规则的图形，一般我们都是用图片，今天就在这里教大家怎样用css代码写出各种规则不同的图形
1.正方形
#square {width: 100px;height: 100px;background: red;}
2.长方形
#rectangle { width: 200px; height: 100px; background: red;}
3.左上三角
#triangle-topleft { width: 0; height: 0; border-top: 100px solid red; border-right: 100px solid transparent; }
4.右上三角
#triangle-topright { width: 0; height: 0; border-top: 100px solid red; border-left: 100px solid transparent;}
5.左下三角
#triangle-bottomleft { width: 0; height: 0; border-bottom: 100px solid red; border-right: 100px solid transparent; }
6.右下三角
#triangle-bottomright { width: 0; height: 0; border-bottom: 100px solid red; border-left: 100px solid transparent; }
7.平行四边形
#parallelogram { width: 150px; height: 100px; -webkit-transform: skew(20deg); -moz-transform: skew(20deg); -o-transform: skew(20deg); background: red; }
8.梯形
#trapezoid { border-bottom: 100px solid red; border-left: 50px solid transparent; border-right: 50px solid transparent; height: 0; width: 100px; }
9.六角星
#star-six { width: 0; height: 0; border-left: 50px solid transparent; border-right: 50px solid transparent; border-bottom: 100px solid red; position: relative; }
#star-six:after { width: 0; height: 0; border-left: 50px solid transparent; border-right: 50px solid transparent; border-top: 100px solid red; position: absolute; content: ""; top: 30px; left: -50px; }
10.五角星
#star-five { margin: 50px 0; position: relative; display: block; color: red; width: 0px; height: 0px; border-right: 100px solid transparent; border-bottom: 70px solid red; border-left: 100px solid transparent; -moz-transform: rotate(35deg); -webkit-transform: rotate(35deg); -ms-transform: rotate(35deg); -o-transform: rotate(35deg); }
#star-five:before { border-bottom: 80px solid red; border-left: 30px solid transparent; border-right: 30px solid transparent; position: absolute; height: 0; width: 0; top: -45px; left: -65px; display: block; content: ‘‘; -webkit-transform: rotate(-35deg); -moz-transform: rotate(-35deg); -ms-transform: rotate(-35deg); -o-transform: rotate(-35deg); }
#star-five:after { position: absolute; display: block; color: red; top: 3px; left: -105px; width: 0px; height: 0px; border-right: 100px solid transparent; border-bottom: 70px solid red; border-left: 100px solid transparent; -webkit-transform: rotate(-70deg); -moz-transform: rotate(-70deg); -ms-transform: rotate(-70deg); -o-transform: rotate(-70deg); content: ‘‘; }
11.五边形
#pentagon { position: relative; width: 54px; border-width: 50px 18px 0; border-style: solid; border-color: red transparent; }
#pentagon:before { content: ""; position: absolute; height: 0; width: 0; top: -85px; left: -18px; border-width: 0 45px 35px; border-style: solid; border-color: transparent transparent red; }
12.六边形
#hexagon { width: 100px; height: 55px; background: red; position: relative; }
#hexagon:before { content: ""; position: absolute; top: -25px; left: 0; width: 0; height: 0; border-left: 50px solid transparent; border-right: 50px solid transparent; border-bottom: 25px solid red; }
#hexagon:after { content: ""; position: absolute; bottom: -25px; left: 0; width: 0; height: 0; border-left: 50px solid transparent; border-right: 50px solid transparent; border-top: 25px solid red; }
13.桃心
#heart { position: relative; width: 100px; height: 90px; }
#heart:before,
#heart:after { position: absolute; content: ""; left: 50px; top: 0; width: 50px; height: 80px; background: red; -moz-border-radius: 50px 50px 0 0; border-radius: 50px 50px 0 0; -webkit-transform: rotate(-45deg); -moz-transform: rotate(-45deg); -ms-transform: rotate(-45deg); -o-transform: rotate(-45deg); transform: rotate(-45deg); -webkit-transform-origin: 0 100%; -moz-transform-origin: 0 100%; -ms-transform-origin: 0 100%; -o-transform-origin: 0 100%; transform-origin: 0 100%; }
#heart:after { left: 0; -webkit-transform: rotate(45deg); -moz-transform: rotate(45deg); -ms-transform: rotate(45deg); -o-transform: rotate(45deg); transform: rotate(45deg); -webkit-transform-origin: 100% 100%; -moz-transform-origin: 100% 100%; -ms-transform-origin: 100% 100%; -o-transform-origin: 100% 100%; transform-origin :100% 100%; }
14.无限大符号
#infinity { position: relative; width: 212px; height: 100px; }
#infinity:before,
#infinity:after { content: ""; position: absolute; top: 0; left: 0; width: 60px; height: 60px; border: 20px solid red; -moz-border-radius: 50px 50px 0 50px; border-radius: 50px 50px 0 50px; -webkit-transform: rotate(-45deg); -moz-transform: rotate(-45deg); -ms-transform: rotate(-45deg); -o-transform: rotate(-45deg); transform: rotate(-45deg); }
#infinity:after { left: auto; right: 0; -moz-border-radius: 50px 50px 50px 0; border-radius: 50px 50px 50px 0; -webkit-transform: rotate(45deg); -moz-transform: rotate(45deg); -ms-transform: rotate(45deg); -o-transform: rotate(45deg); transform: rotate(45deg); }
15.蛋
#egg { display:block; width: 126px; height: 180px; background-color: red; -webkit-border-radius: 63px 63px 63px 63px / 108px 108px 72px 72px; border-radius: 50% 50% 50% 50% / 60% 60% 40% 40%; }
16.提示对话框
#talkbubble { width: 120px; height: 80px; background: red; position: relative; -moz-border-radius: 10px; -webkit-border-radius: 10px; border-radius: 10px; }
#talkbubble:before { content:""; position: absolute; right: 100%; top: 26px; width: 0; height: 0; border-top: 13px solid transparent; border-right: 26px solid red; border-bottom: 13px solid transparent; }
17.十二角星
#burst-8 { background: red; width: 80px; height: 80px; position: relative; text-align: center; -webkit-transform: rotate(20deg); -moz-transform: rotate(20deg); -ms-transform: rotate(20deg); -o-transform: rotate(20eg); transform: rotate(20deg); }
#burst-8:before { content: ""; position: absolute; top: 0; left: 0; height: 80px; width: 80px; background: red; -webkit-transform: rotate(135deg); -moz-transform: rotate(135deg); -ms-transform: rotate(135deg); -o-transform: rotate(135deg); transform: rotate(135deg); }
18.八角星
#burst-8 { background: red; width: 80px; height: 80px; position: relative; text-align: center; -webkit-transform: rotate(20deg); -moz-transform: rotate(20deg); -ms-transform: rotate(20deg); -o-transform: rotate(20eg); transform: rotate(20deg); }
#burst-8:before { content: ""; position: absolute; top: 0; left: 0; height: 80px; width: 80px; background: red; -webkit-transform: rotate(135deg); -moz-transform: rotate(135deg); -ms-transform: rotate(135deg); -o-transform: rotate(135deg); transform: rotate(135deg); }
19.钻石
#cut-diamond { border-style: solid; border-color: transparent transparent red transparent; border-width: 0 25px 25px 25px; height: 0; width: 50px; position: relative; margin: 20px 0 50px 0; }
#cut-diamond:after { content: ""; position: absolute; top: 25px; left: -25px; width: 0; height: 0; border-style: solid; border-color: red transparent transparent transparent; border-width: 70px 50px 0 50px; }
20.八卦
#yin-yang { width: 96px; height: 48px; background:
#eee; border-color: red; border-style: solid; border-width: 2px 2px 50px 2px; border-radius: 100%; position: relative; }
#yin-yang:before { content: ""; position: absolute; top: 50%; left: 0; background:
#eee; border: 18px solid red; border-radius: 100%; width: 12px; height: 12px; }
#yin-yang:after { content: ""; position: absolute; top: 50%; left: 50%; background: red; border: 18px solid
#eee; border-radius:100%; width: 12px; height: 12px; }
CSS代码写出的各种形状图形