Is it possible to make a rounded triangle with just CSS?

Question

I'm trying to make the following shape with just CSS:

Here is what I currently have:

 .triangle { width: 0; height: 0; border-style: solid; border-width: 56px 56px 0 0; border-color: #ff4369 transparent transparent transparent; } 

 <div class="triangle"> </div> 

I'm unable to use border radius to make the top-left corner rounded... Is there another way to do this or do I need to use an SVG?

Answer 1

Yes it's possible using border-radius :

 .triangle { box-sizing: border-box; width: 60px; height: 60px; border-top: solid 30px rgb(200,30,50); border-left: solid 30px rgb(200,30,50); border-top-left-radius: 12px; border-right: solid 30px transparent; border-bottom: solid 30px transparent; } 

 <div class="triangle triangle-0"></div> 

Answer 2

You might consider the border-radius and clip-path: polygon() solution:

 .triangle { width: 56px; height: 56px; background: #ff4369; border-top-left-radius: 12px; -webkit-clip-path: polygon(0 0, 0% 100%, 100% 0); clip-path: polygon(0 0, 0% 100%, 100% 0); } 

 <div class="triangle"></div> 

And another solution with the :before or :after pseudo-element , which can serve as a layer:

 .triangle { width: 56px; height: 56px; background: #ff4369; border-top-left-radius: 12px; position: relative; overflow: hidden; } .triangle:after { content: ""; position: absolute; top: 0; left: 50%; width: 100%; height: 100%; background: #fff; transform: skew(-45deg); } 

 <div class="triangle"></div> 

Answer 3

You can easily do with linear-gradient and it's well supported:

 body { background: #ccc; } .triangle { margin: 10px; width: 56px; height: 56px; background: linear-gradient(to bottom right, #ff4369 50%, transparent 0); border-radius: 10px 0 0 0; } 

 <div class="triangle"> </div> 

Answer 4

To actually answer your question (and provide the first answer without border-radius ): If you want a CSS only solution, you will have to use border-radius .

Nevertheless I would highly recommend to use SVG for creating shapes, as simple shapes like this are easy to create manually, it's responsive, it's widely supported now and (as @chharvey mentioned in the comments) semantically more appropriate.

 <svg viewbox="0 0 50 50" height="56px"> <path d="M1 50 V10 Q1 1 10 1 H50z" fill="#ff4369" /> </svg> 

You can find more information about the path properties in the specs .