How to make a curved edge hexagon by using CSS

Question

This is my CSS.

CSS

#hexagon-circle { 
    width: 100px; 
    height: 55px; 
    background: red; 
    position: relative;
    border-radius: 10px;} 
#hexagon-circle:before { 
    content: ""; 
    position: absolute; 
    top: -25px; 
    left: 0; 
    width: 0; 
    height: 0; 
    border-left: 50px solid transparent; 
    border-right: 50px solid transparent; 
    border-bottom: 29px solid red;
    border-radius: 10px;} 
#hexagon-circle:after { 
    content: ""; 
    position: absolute; 
    bottom: -25px; 
    left: 0; 
    width: 0; 
    height: 0; 
    border-left: 50px solid transparent; 
    border-right: 50px solid transparent; 
    border-top: 29px solid red;
    border-radius: 10px;}

The output is 4 edges of hexagon is curved, but top and the bottom is not. I want to make all edge of hexagon curved. How to make top and bottom edge to be curved? or How to make the top edge of triangle to be curved?

http://jsfiddle.net/yR7zt/1

Answer 1

I will consider the same trick I used in the previous answer Where I will build the hexagon using clip-path

.hex {
  width: 200px;
  display: inline-block;
  color:orange;
}

.hex::before {
  content: "";
  display: block;
  background:currentColor;
  padding-top: 90%;
  clip-path: polygon(25% 0%, 75% 0%, 100% 50%, 75% 100%, 25% 100%, 0% 50%);
}

<div class="hex"></div>

Then I will apply an SVG filter:

.hex {
  width: 200px;
  display: inline-block;
  color:orange;
  filter: url('#goo');
}

.hex::before {
  content: "";
  display: block;
  background:currentColor;
  padding-top: 86.6%; /* 100%*cos(30) */
  clip-path: polygon(25% 0%, 75% 0%, 100% 50%, 75% 100%, 25% 100%, 0% 50%);
}

<div class="hex"></div>
<div class="hex" style="color:blue;width:150px;"></div>
<div class="hex" style="color:red;width:100px;"></div>


<svg style="visibility: hidden; position: absolute;" width="0" height="0" xmlns="http://www.w3.org/2000/svg" version="1.1">
  <defs>
        <filter id="goo"><feGaussianBlur in="SourceGraphic" stdDeviation="8" result="blur" />    
            <feColorMatrix in="blur" mode="matrix" values="1 0 0 0 0  0 1 0 0 0  0 0 1 0 0  0 0 0 19 -9" result="goo" />
            <feComposite in="SourceGraphic" in2="goo" operator="atop"/>
        </filter>
    </defs>
</svg>

And in the opposite direction

.hex {
  width: 200px;
  display: inline-block;
  margin:0 5px;
  color:orange;
  filter: url('#goo');
}

.hex::before {
  content: "";
  display: block;
  background:currentColor;
  padding-top: 115%; /* 100%/cos(30)  */
  clip-path: polygon(0% 25%,0% 75%,50% 100%,100% 75%,100% 25%,50% 0%);
}

<div class="hex"></div>
<div class="hex" style="color:blue;width:150px;"></div>
<div class="hex" style="color:red;width:100px;"></div>


<svg style="visibility: hidden; position: absolute;" width="0" height="0" xmlns="http://www.w3.org/2000/svg" version="1.1">
  <defs>
        <filter id="goo"><feGaussianBlur in="SourceGraphic" stdDeviation="8" result="blur" />    
            <feColorMatrix in="blur" mode="matrix" values="1 0 0 0 0  0 1 0 0 0  0 0 1 0 0  0 0 0 19 -9" result="goo" />
            <feComposite in="SourceGraphic" in2="goo" operator="atop"/>
        </filter>
    </defs>
</svg>