纯CSS画的基本图形（矩形、圆形、三角形、多边形、爱心、八卦等）,里面很多涉及到CSS3的一些属性。

   图形包括基本的矩形、圆形、椭圆、三角形、多边形，也包括稍微复杂一点的爱心、钻石、阴阳八卦。其中绝大部分涉及到CSS3中的border-radius，text-shadow，transform等一些比较复杂的属性，所以需要有一点CSS3基础的最好。特别注意的是此效果不兼容IE<9的浏览器，最好用firefox，chrome等浏览器。以下案例都由本人亲自测试，希望好学您也可以一一测试一下。

1.正方形

1 #square {2     width: 100px;3     height: 100px;4     background: red;5 }

2.长方形

1 #rectangle {2     width: 200px;3     height: 100px;4     background: red;5 }

3.圆形

1 #circle {2     width: 100px;3     height: 100px;4     background: red;5     -moz-border-radius: 50px;6     -webkit-border-radius: 50px;7     border-radius: 50px;8 }

4.椭圆

1 #oval {2     width: 200px;3     height: 100px;4     background: red;5     -moz-border-radius: 100px / 50px;6     -webkit-border-radius: 100px / 50px;7     border-radius: 100px / 50px;8 }

5.上三角

1 #triangle-up {2     width: 0;3     height: 0;4     border-left: 50px solid transparent;5     border-right: 50px solid transparent;6     border-bottom: 100px solid red;7 }

6.下三角

1 #triangle-down {2     width: 0;3     height: 0;4     border-left: 50px solid transparent;5     border-right: 50px solid transparent;6     border-top: 100px solid red;7 }

7.左三角

1 #triangle-left {2     width: 0;3     height: 0;4     border-top: 50px solid transparent;5     border-right: 100px solid red;6     border-bottom: 50px solid transparent;7 }

8.右三角

1 #triangle-right {2     width: 0;3     height: 0;4     border-top: 50px solid transparent;5     border-left: 100px solid red;6     border-bottom: 50px solid transparent;7 }

9.左上三角

1 #triangle-topleft {2     width: 0;3     height: 0;4     border-top: 100px solid red;5     border-right: 100px solid transparent;         6 }

10.右上三角

1 #triangle-topright {2     width: 0;3     height: 0;4     border-top: 100px solid red;5     border-left: 100px solid transparent;6      7 }

11.左下三角

1 #triangle-bottomleft {2     width: 0;3     height: 0;4     border-bottom: 100px solid red;5     border-right: 100px solid transparent; 6 }

12.右下三角

1 #triangle-bottomright {2     width: 0;3     height: 0;4     border-bottom: 100px solid red;5     border-left: 100px solid transparent;6 }

13.平行四边形

1 #parallelogram {2     width: 150px;3     height: 100px;4         margin-left:20px;5     -webkit-transform: skew(20deg);6        -moz-transform: skew(20deg);7          -o-transform: skew(20deg);8     background: red;9 }

14.梯形

1 #trapezoid {2     border-bottom: 100px solid red;3     border-left: 50px solid transparent;4     border-right: 50px solid transparent;5     height: 0;6     width: 100px;7 }

15.六角星

 1 #star-six { 2     width: 0; 3     height: 0; 4     border-left: 50px solid transparent; 5     border-right: 50px solid transparent; 6     border-bottom: 100px solid red; 7     position: relative; 8 } 9 #star-six:after {10     width: 0;11     height: 0;12     border-left: 50px solid transparent;13     border-right: 50px solid transparent;14     border-top: 100px solid red;15     position: absolute;16     content: "";17     top: 30px;18     left: -50px;19 }

16.五角星

 1 #star-five { 2    margin: 50px 0; 3    position: relative; 4    display: block; 5    color: red; 6    width: 0px; 7    height: 0px; 8    border-right:  100px solid transparent; 9    border-bottom: 70px  solid red;10    border-left:   100px solid transparent;11    -moz-transform:    rotate(35deg);12    -webkit-transform: rotate(35deg);13    -ms-transform:     rotate(35deg);14    -o-transform:      rotate(35deg);15 }16 #star-five:before {17    border-bottom: 80px solid red;18    border-left: 30px solid transparent;19    border-right: 30px solid transparent;20    position: absolute;21    height: 0;22    width: 0;23    top: -45px;24    left: -65px;25    display: block;26    content: '';27    -webkit-transform: rotate(-35deg);28    -moz-transform:    rotate(-35deg);29    -ms-transform:     rotate(-35deg);30    -o-transform:      rotate(-35deg);31     32 }33 #star-five:after {34    position: absolute;35    display: block;36    color: red;37    top: 3px;38    left: -105px;39    width: 0px;40    height: 0px;41    border-right: 100px solid transparent;42    border-bottom: 70px solid red;43    border-left: 100px solid transparent;44    -webkit-transform: rotate(-70deg);45    -moz-transform:    rotate(-70deg);46    -ms-transform:     rotate(-70deg);47    -o-transform:      rotate(-70deg);48    content: '';49 }

17.五角大楼

 1 #pentagon { 2     position: relative; 3     width: 54px; 4     border-width: 50px 18px 0; 5     border-style: solid; 6     border-color: red transparent; 7 } 8 #pentagon:before { 9     content: "";10     position: absolute;11     height: 0;12     width: 0;13     top: -85px;14     left: -18px;15     border-width: 0 45px 35px;16     border-style: solid;17     border-color: transparent transparent red;18 }

18.六边形

 1 #hexagon { 2     width: 100px; 3     height: 55px; 4     background: red; 5     position: relative; 6 } 7 #hexagon:before { 8     content: ""; 9     position: absolute;10     top: -25px;11     left: 0;12     width: 0;13     height: 0;14     border-left: 50px solid transparent;15     border-right: 50px solid transparent;16     border-bottom: 25px solid red;17 }18 #hexagon:after {19     content: "";20     position: absolute;21     bottom: -25px;22     left: 0;23     width: 0;24     height: 0;25     border-left: 50px solid transparent;26     border-right: 50px solid transparent;27     border-top: 25px solid red;28 }

19.八角形

 1 #octagon { 2     width: 100px; 3     height: 100px; 4     background: red; 5     position: relative; 6 } 7   8 #octagon:before { 9     content: "";10     position: absolute;11     top: 0;12     left: 0;   13     border-bottom: 29px solid red;14     border-left: 29px solid #eee;15     border-right: 29px solid #eee;16     width: 42px;17     height: 0;18 }19  20 #octagon:after {21     content: "";22     position: absolute;23     bottom: 0;24     left: 0;   25     border-top: 29px solid red;26     border-left: 29px solid #eee;27     border-right: 29px solid #eee;28     width: 42px;29     height: 0;30 }

20.爱心

 1 #heart { 2     position: relative; 3     width: 100px; 4     height: 90px; 5 } 6 #heart:before, 7 #heart:after { 8     position: absolute; 9     content: "";10     left: 50px;11     top: 0;12     width: 50px;13     height: 80px;14     background: red;15     -moz-border-radius: 50px 50px 0 0;16     border-radius: 50px 50px 0 0;17     -webkit-transform: rotate(-45deg);18        -moz-transform: rotate(-45deg);19         -ms-transform: rotate(-45deg);20          -o-transform: rotate(-45deg);21             transform: rotate(-45deg);22     -webkit-transform-origin: 0 100%;23        -moz-transform-origin: 0 100%;24         -ms-transform-origin: 0 100%;25          -o-transform-origin: 0 100%;26             transform-origin: 0 100%;27 }28 #heart:after {29     left: 0;30     -webkit-transform: rotate(45deg);31        -moz-transform: rotate(45deg);32         -ms-transform: rotate(45deg);33          -o-transform: rotate(45deg);34             transform: rotate(45deg);35     -webkit-transform-origin: 100% 100%;36        -moz-transform-origin: 100% 100%;37         -ms-transform-origin: 100% 100%;38          -o-transform-origin: 100% 100%;39             transform-origin :100% 100%;40 }

21.无穷大符号

 1 #infinity { 2     position: relative; 3     width: 212px; 4     height: 100px; 5 } 6   7 #infinity:before, 8 #infinity:after { 9     content: "";10     position: absolute;11     top: 0;12     left: 0;13     width: 60px;14     height: 60px;   15     border: 20px solid red;16     -moz-border-radius: 50px 50px 0 50px;17          border-radius: 50px 50px 0 50px;18     -webkit-transform: rotate(-45deg);19        -moz-transform: rotate(-45deg);20         -ms-transform: rotate(-45deg);21          -o-transform: rotate(-45deg);22             transform: rotate(-45deg);23 }24  25 #infinity:after {26     left: auto;27     right: 0;28     -moz-border-radius: 50px 50px 50px 0;29          border-radius: 50px 50px 50px 0;30     -webkit-transform: rotate(45deg);31        -moz-transform: rotate(45deg);32         -ms-transform: rotate(45deg);33          -o-transform: rotate(45deg);34             transform: rotate(45deg);35 }

22.鸡蛋

1 #egg {2    display:block;3    width: 126px;4    height: 180px;5    background-color: red;6    -webkit-border-radius: 63px 63px 63px 63px / 108px 108px 72px 72px;7    border-radius:        50%   50%  50%  50%  / 60%   60%   40%  40%;8 }

23.食逗人

 1 #pacman { 2   width: 0px; 3   height: 0px; 4   border-right: 60px solid transparent; 5   border-top: 60px solid red; 6   border-left: 60px solid red; 7   border-bottom: 60px solid red; 8   border-top-left-radius: 60px; 9   border-top-right-radius: 60px;10   border-bottom-left-radius: 60px;11   border-bottom-right-radius: 60px;12 }

24.对话框

 1 #talkbubble { 2    width: 120px; 3    height: 80px; 4    background: red; 5    position: relative; 6    -moz-border-radius:    10px; 7    -webkit-border-radius: 10px; 8    border-radius:         10px; 9 }10 #talkbubble:before {11    content:"";12    position: absolute;13    right: 100%;14    top: 26px;15    width: 0;16    height: 0;17    border-top: 13px solid transparent;18    border-right: 26px solid red;19    border-bottom: 13px solid transparent;20 }

25.十二角星

 1 #burst-12 { 2     background: red; 3     width: 80px; 4     height: 80px; 5     position: relative; 6     text-align: center; 7 } 8 #burst-12:before, #burst-12:after { 9     content: "";10     position: absolute;11     top: 0;12     left: 0;13     height: 80px;14     width: 80px;15     background: red;16 }17 #burst-12:before {18     -webkit-transform: rotate(30deg);19        -moz-transform: rotate(30deg);20         -ms-transform: rotate(30deg);21          -o-transform: rotate(30deg);22             transform: rotate(30deg);23 }24 #burst-12:after {25     -webkit-transform: rotate(60deg);26        -moz-transform: rotate(60deg);27         -ms-transform: rotate(60deg);28          -o-transform: rotate(60deg);29             transform: rotate(60deg);30 }

26.八角星

 1 #burst-8 { 2     background: red; 3     width: 80px; 4     height: 80px; 5     position: relative; 6     text-align: center; 7     -webkit-transform: rotate(20deg); 8        -moz-transform: rotate(20deg); 9         -ms-transform: rotate(20deg);10          -o-transform: rotate(20eg);11             transform: rotate(20deg);12 }13 #burst-8:before {14     content: "";15     position: absolute;16     top: 0;17     left: 0;18     height: 80px;19     width: 80px;20     background: red;21     -webkit-transform: rotate(135deg);22        -moz-transform: rotate(135deg);23         -ms-transform: rotate(135deg);24          -o-transform: rotate(135deg);25             transform: rotate(135deg);26 }

27.钻石

 1 #cut-diamond { 2     border-style: solid; 3     border-color: transparent transparent red transparent; 4     border-width: 0 25px 25px 25px; 5     height: 0; 6     width: 50px; 7     position: relative; 8     margin: 20px 0 50px 0; 9 }10 #cut-diamond:after {11     content: "";12     position: absolute;13     top: 25px;14     left: -25px;15     width: 0;16     height: 0;17     border-style: solid;18     border-color: red transparent transparent transparent;19     border-width: 70px 50px 0 50px;20 }

28.阴阳八卦

 1 #yin-yang { 2     width: 96px; 3     height: 48px; 4     background: #eee; 5     border-color: red; 6     border-style: solid; 7     border-width: 2px 2px 50px 2px; 8     border-radius: 100%; 9     position: relative;10 }11  12 #yin-yang:before {13     content: "";14     position: absolute;15     top: 50%;16     left: 0;17     background: #eee;18     border: 18px solid red;19     border-radius: 100%;20     width: 12px;21     height: 12px;22 }23  24 #yin-yang:after {25     content: "";26     position: absolute;27     top: 50%;28     left: 50%;29     background: red;30     border: 18px solid #eee;31     border-radius:100%;32     width: 12px;33     height: 12px;34 }

总结：个人觉得很多的效果是通过CSS3实现的，后面几个都是还算比较复杂的。实际项目中运用的基本也就是这样方法的比较多一点。

原本出自：http://css-tricks.com/examples/ShapesOfCSS/

来源：https://www.cnblogs.com/jshoukun/archive/2012/02/06/2340437.html