网站建设时可以用到的很有动感菜单效果，用在移动端效果也很好

<h1>Gooey Menu</h1>
<h2>Using CSS and SVG Filters</h2>
<h3>By <a href="https://codepen.io/lbebber">Lucas Bebber</a></h3>
<h4><a href="https://codepen.io/lbebber/pen/LELBEo" target="_blank">Version 1</a> – <a href="https://codepen.io/lbebber/pen/RNgBPP" target="_blank">Version 2</a> – Version 3 – <a href="https://codepen.io/lbebber/pen/rawQKR" target="_blank">Version 4</a></h4>
<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/font-awesome/4.3.0/css/font-awesome.min.css"/>

<nav class="menu">
<input type="checkbox" href="#" class="menu-open" name="menu-open" id="menu-open"/>
<label class="menu-open-button" for="menu-open">
<span class="hamburger hamburger-1"></span>
<span class="hamburger hamburger-2"></span>
<span class="hamburger hamburger-3"></span>
</label>

<a href="#" class="menu-item"> <i class="fa fa-bar-chart"></i> </a>
<a href="#" class="menu-item"> <i class="fa fa-plus"></i> </a>
<a href="#" class="menu-item"> <i class="fa fa-heart"></i> </a>
<a href="#" class="menu-item"> <i class="fa fa-envelope"></i> </a>

</nav>

<!– filters –>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1">
<defs>
<filter id="shadowed-goo">

<fegaussianblur in="SourceGraphic" result="blur" stdDeviation="10"></fegaussianblur>
<fecolormatrix in="blur" mode="matrix" values="1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 18 -7" result="goo"></fecolormatrix>
<fegaussianblur in="goo" stdDeviation="3" result="shadow"></fegaussianblur>
<fecolormatrix in="shadow" mode="matrix" values="0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 -0.2" result="shadow"></fecolormatrix>
<feoffset in="shadow" dx="1" dy="1" result="shadow"></feoffset>
<fecomposite in2="shadow" in="goo" result="goo"></fecomposite>
<fecomposite in2="goo" in="SourceGraphic" result="mix"></fecomposite>
</filter>
<filter id="goo">
<fegaussianblur in="SourceGraphic" result="blur" stdDeviation="10"></fegaussianblur>
<fecolormatrix in="blur" mode="matrix" values="1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 18 -7" result="goo"></fecolormatrix>
<fecomposite in2="goo" in="SourceGraphic" result="mix"></fecomposite>
</filter>
</defs>
</svg>

@import "compass/css3";

//vars
$fg:#00bcd4;
$bg:#673ab7;
$pi:3.14;

//config
$menu-items:4;
$open-distance:105px;
$opening-angle:$pi*2;

body{
background:$bg;
color:white;
text-align:center;
}
a{
color:inherit;
}
h1, h2, h3, h4{
margin:0;
margin-bottom:10px;
margin-top:10px;
}
h1{
font-size:3em;
}
%goo{
filter:url('#shadowed-goo');
// debug
//background:rgba(255,0,0,0.2);
}
%ball{
background:$fg;
border-radius:100%;
width:80px;
height:80px;
margin-left:-40px;
position:absolute;
top:20px;
color:white;
text-align:center;
line-height:80px;
transform:translate3d(0,0,0);
transition:transform ease-out 200ms;
}
.menu-open{
display:none;
}
.menu-item{
@extend %ball;
}
.hamburger{
$width:25px;
$height:3px;
width:$width;
height:$height;
background:white;
display:block;
position:absolute;
top:50%;
left:50%;
margin-left:-$width/2;
margin-top:-$height/2;
transition:transform 200ms;
}
$hamburger-spacing:8px;
.hamburger-1{
transform:translate3d(0,-$hamburger-spacing,0);
}
.hamburger-2{
transform:translate3d(0,0,0);
}
.hamburger-3{
transform:translate3d(0,$hamburger-spacing,0);
}
.menu-open:checked+.menu-open-button{
.hamburger-1{
transform:translate3d(0,0,0) rotate(45deg);
}
.hamburger-2{
transform:translate3d(0,0,0) scale(0.1,1);
}
.hamburger-3{
transform:translate3d(0,0,0) rotate(-45deg);
}
}
.menu{
@extend %goo;
$width:650px;
$height:150px;
position:absolute;
left:50%;
margin-left:-80px;
padding-top:20px;
padding-left:80px;
width:$width;
height:$height;
box-sizing:border-box;
font-size:20px;
text-align:left;
}

.menu-item{
&:hover{
background:white;
color:$fg;
}
@for $i from 1 through $menu-items{
&:nth-child(#{$i+2}){
transition-duration:180ms;
}
}
}

.menu-open-button{
@extend %ball;
z-index:2;
transition-timing-function:cubic-bezier(0.175, 0.885, 0.320, 1.275);
transition-duration:400ms;
transform:scale(1.1,1.1) translate3d(0,0,0);
cursor:pointer;
}
.menu-open-button:hover{
transform:scale(1.2,1.2) translate3d(0,0,0);
}
.menu-open:checked+.menu-open-button{
transition-timing-function:linear;
transition-duration:200ms;
transform:scale(0.8,0.8) translate3d(0,0,0);
}

.menu-open:checked~.menu-item{
transition-timing-function:cubic-bezier(0.165, 0.840, 0.440, 1.000);
@for $i from 1 through $menu-items{

&:nth-child(#{$i+2}){
transition-duration:90ms+(100ms*$i);
transform:translate3d(110px*$i,0,0);
}
}
}