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Use npm Packages

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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.


	<div class="nav-wrap">
		  <a class="main-nav">点我</a>
              * {
  margin: 0;
  padding: 0;
body {
  background-color: #292a38;
  font-family: "Microsoft Yahei";
h1 {
  margin-top: 20px;
  text-align: center;
  color: #fff;

.nav-wrap {
  position: relative;
  width: 200px;
  height: 200px;
  margin: 50px auto;
  border: 2px dotted #4e5061;
  border-radius: 50%;
.nav-wrap .main-nav {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%,-50%);
  width: 40px;
  height: 40px;
  line-height: 40px;
  font-size: 12px;
  text-align: center;
  text-decoration: none;
  color: #fff;
  border-radius: 3px;
  text-shadow: 1px 1px 0px #000;
  background: #15a5f3;
  cursor: pointer;
.nav-wrap nav {
  position: absolute;
  width: 100%;
  height: 100%;
  transform: scale(0);
  transition: all 0.5s ease-out;
  opacity: 0;
.nav-wrap.active nav {
  transform: scale(1);
  opacity: 1;
.nav-wrap nav > a{
  position: absolute;
  width: 30px;
  height: 30px;
  background: #f44283;
  text-align: center;
  line-height: 30px;
  text-decoration: none;
  color: #fff;
  border-radius: 3px;
  text-shadow: 1px 1px 0px #000;
  transform: translate(-50%,-50%);
              var isLocated = false;

	var me = $(this),
		  navWrap = me.closest('.nav-wrap'), // 动画效果的父容器
		  navs = navWrap.find('nav a'); // 父容器中的所有子菜单

	// 当菜单没被激活时
	if(!navWrap.hasClass('active') && !isLocated){

		// 圆的半径 raduis
		var width = navWrap.width(),
			  radius = width / 2;

		// 圆形菜单的起始、终止角度
		var startAngle = 0,
			  endAngle = 360;

		// 两个子菜单间的夹角 gap
		var total = navs.length,
			  gap = (endAngle - startAngle)/total;

		// 角度->弧度
		var radian = Math.PI / 180;

		 * 计算并确定各个子菜单的最终位置
		$.each(navs, function(index, item){

			// 当前子菜单与x轴正向的夹角 θ (角度->弧度)
			var myAngle = (startAngle + gap*index) * radian;  // θ

			// 计算当前子菜单相对于左上角(0,0)的坐标 (x,y)
			var myX = radius + radius * Math.cos( myAngle ), // x=r+rcos(θ)
				  myY = radius + radius * Math.sin( myAngle ); // y=r+rsin(θ)
			// 设置当前子菜单的位置 (left,top) = (x,y)
                    left: myX + 'px',
                    top:  myY + 'px'

		isLocated = true;

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