CSS3 painted five-pointed star and the Star of David

The final effect you want to achieve

First, the five-pointed star

Before painting pentagram first analyze how the five-pointed star is achieved by several parts which constituted diagram is as follows:

Three apex upward triangles, by providing the rotation and positioning of the splice and to overlap each other to achieve the final effect of the five-pointed star.

And semantic codes for easier, the use of pseudo-class to add content.

1, an isosceles triangle is provided, and using the appropriate transform to the rotation angle to transform: rotate (35deg);

.star { 
        width : 0px ; height : 0px ; 
        border-bottom : 70px Solid RGBA (244,0,0,0.4) ; 
        border-left : 100px Solid transparent ; 
        border-right : 100px Solid transparent ; 
        margin : 100px Auto ;
         / * up to this step, obtained is an isosceles triangle upwardly * / 
        -webkit-Transform : Rotate (35 deg) ; 
        -ms-Transform : Rotate (35 deg) ; 
        -o-Transform :Rotate (35 deg) ; 
        Transform : Rotate (35 deg) ;
         / * rotate clockwise 35 deg * / 
        position : relative ; 
    }

2, using : before pseudo-element is added in front of the div element content.

Content of the added pseudo-classes inherit div style has also undergone a clockwise rotation, so if you eliminate the influence clockwise rotation, can transform: rotate (-35deg);

A positioning, adjusted to the appropriate content location top: -45px; left: -65px;

.star:before{
        content:"";
        width:0px;
        height:0px;
        border-bottom:80px solid rgba(0,244,0,0.5);
        border-left:30px solid transparent;
        border-right:30px solid transparent;
        /*伪类所添加的内容继承原来的样式也发生了顺时针旋转*/
        -webkit-transform: rotate(-35deg);
        -ms-transform: rotate(-35deg);
        -o-transform: rotate(-35deg);
        transform: rotate(-35deg);
        /*设置负值，就会逆时针旋转*/
        position:absolute;
        top:-45px;left:-65px;
        /*定位调整位置*/
    }

3、使用 :after 伪类在div 元素后面添加内容

将内容旋转到合适的角度 transform: rotate(-35deg);

设置定位，放置在适当的位置 top:3px;left:105px;

.star:after{
        content:"";
        width:0px;
        height:0px;
        position:absolute;
        border-bottom:70px solid rgba(0,0,244,0.5);
        border-left:100px solid transparent;
        border-right:100px solid transparent;
        -webkit-transform: rotate(-70deg);
        -ms-transform: rotate(-70deg);
        -o-transform: rotate(-70deg);
        transform: rotate(-70deg);
        top:3px;left:-105px;    
    }

实现效果和代码：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>transform</title>
    <style>
    .star{
        width:0px;height:0px;
        border-bottom:70px solid red; 
        /*rgba(244,0,0,0.4);*/
        border-left:100px solid transparent;
        border-right:100px solid transparent;
        margin:100px auto;
        /*到这一步为止，得到的是一个向上的等腰三角形*/
        -webkit-transform: rotate(35deg);
        -ms-transform: rotate(35deg);
        -o-transform: rotate(35deg);
        transform: rotate(35deg);
        /*顺时针旋转35deg*/
        position:relative;
    }
    .star:before{
        content:"";
        width:0px;
        height:0px;
        border-bottom:80px solid red; 
        /*rgba(0,244,0,0.5);*/
        border-left:30px solid transparent;
        border-right:30px solid transparent;
        /*伪类所添加的内容继承原来的样式也发生了顺时针旋转*/
        -webkit-transform: rotate(-35deg);
        -ms-transform: rotate(-35deg);
        -o-transform: rotate(-35deg);
        transform: rotate(-35deg);
        /*设置负值，就会逆时针旋转*/
        position:absolute;
        top:-45px;
        left:-65px;
        /*定位调整位置*/
    }
    .star:after{
        content:"";
        width:0px;
        height:0px;
        position:absolute;
        border-bottom:70px solid red;
        /*rgba(0,0,244,0.5);*/
        border-left:100px solid transparent;
        border-right:100px solid transparent;
        -webkit-transform: rotate(-70deg);
        -ms-transform: rotate(-70deg);
        -o-transform: rotate(-70deg);
        transform: rotate(-70deg);
        top:3px;left:-105px;    
    }
    </style>
</head>
<body>
    <div class="star"></div>
</body>
</html>

二、六角星

相比于五角星，六角星就简单的多了，来是先来分析它是如何构成的：

两个三角形交叠实现

注意两个三角形之间的位置关系，设置正确的定位。

代码：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
    <style>
    #star{
        width:0px;height:0px;
        border-bottom:100px solid red;
        /*rgba(244,244,0,0.4);*/
        border-left:50px solid transparent;
        border-right:50px solid transparent;
        margin:50px auto;
        position:relative;
    }
    #star:after{
        content:" ";
        width:0px;height:0px;
        border-top:100px solid red;
        /*rgba(0,244,250,0.6);*/
        border-left:50px solid transparent;
        border-right:50px solid transparent;
        position:absolute;
        top:50px;left:-50px;
    }
    </style>
</head>
<body>
    <div id="star"></div>
</body>
</html>