Tabs border with triangle with CSS - css

Question

I am trying to represent my HTML/CSS tab like on the picture.
I have already tried lots of things with border-radius without any success.
Do you have any tracks so that I can reproduce my tabs like the picture only with CSS?

Answer 1

In order to make the same borders (also inside the triangles) as in the image, you can use pseudo elements and transform rotate :
DEMO
output :
HTML :
<div>Critiques</div>
<div>Messages sur le forum</div>
<div>Actualités</div>
CSS :
div{
border-top:1px solid #ccc;
border-bottom:1px solid #ccc;
padding-right:12px;
line-height:50px;
float:left;
width:200px;
position:relative;
z-index:0;
text-align:center;
}
div:after,div:before{
content:'';
position:absolute;
width:10px;
height:10px;
background:#fff;
z-index:999;
-ms-transform: rotate(45deg);
-webkit-transform: rotate(45deg);
transform: rotate(45deg);
}
div:before{
border-right:1px solid #ccc;
border-bottom:1px solid #ccc;
top:0; left:-12px;
-ms-transform-origin:100% 0;
-webkit-transform-origin:100% 0;
transform-origin:100% 0;
}
div:after{
border-left:1px solid #ccc;
border-top:1px solid #ccc;
bottom:0;
right:4px;
-ms-transform-origin:0 100%;
-webkit-transform-origin:0 100%;
transform-origin:0 100%;
}
div:first-child:before, div:last-child:after{
display:none;
}

Answer 2

You could that with css only but with an empty span (If you would like to have half triangles in the edges):
HTML
<ul>
<li><span></span>one</li>
<li><span></span>two</li>
<li><span></span>three</li>
</ul>
CSS
ul {
font-size: 0;
}
li {
background: red;
display: inline-block;
padding: 30px;
font-size: 15px;
position: relative;
}
span {
position: absolute;
top: 0;
bottom: 0;
left: 0;
right: 0;
}
li:after {
width: 0;
height: 0;
border-top: 10px solid white;
border-left: 10px solid transparent;
position: absolute;
right: 0;
top: 0;
content: "";
}
li:before {
width: 0;
height: 0;
border-top: 10px solid white;
border-right: 10px solid transparent;
position: absolute;
left: 0;
top: 0;
content: "";
}
span:before {
width: 0;
height: 0;
border-bottom: 10px solid white;
border-right: 10px solid transparent;
position: absolute;
left: 0;
bottom: 0;
content: "";
}
span:after {
width: 0;
height: 0;
border-bottom: 10px solid white;
border-left: 10px solid transparent;
position: absolute;
right: 0;
bottom: 0;
content: "";
}
An example: http://jsfiddle.net/fC9Fs/

Answer 3

Here is another take on it:
This one works with a basic list and no other HTML is needed.
Also as you've shown in your image, the first and last elements do not have the arrow.
Fiddle
HTML:
<ul>
<li>One</li>
<li>Two</li>
<li>Three</li>
</ul>
CSS:
html, body{
background:#E5E2E2;
}
ul{
display:inline-block;
list-style-type:none;
border:1px solid #CCCCCC;
padding:0;
}
li{
float:left;
padding:10px 15px;
background:#F4F4F4;
position:relative;
}
li:nth-child(n+2):before{
content:'';
position:absolute;
left:-5px;
top:-1px;
width: 0;
height: 0;
border-left: 5px solid transparent;
border-right: 5px solid transparent;
border-top: 10px solid #e5e2e2;
}
li:nth-child(n+2):after{
content:'';
position:absolute;
left:-5px;
bottom:-1px;
width: 0;
height: 0;
border-left: 5px solid transparent;
border-right: 5px solid transparent;
border-bottom: 10px solid #e5e2e2;
}

Answer 4

You can do this with an octagon shape, as shown in this link.
The relevant code:
#octagon { width: 100px; height: 100px; background: red; position: relative; }
#octagon:before { content: ""; position: absolute; top: 0; left: 0; border-bottom: 29px solid red; border-left: 29px solid #eee; border-right: 29px solid #eee; width: 42px; height: 0; } #octagon:after { content: ""; position: absolute; bottom: 0; left: 0; border-top: 29px solid red; border-left: 29px solid #eee; border-right: 29px solid #eee; width: 42px; height: 0; }
You can edit the borders from the above code to get the exact shape you want.

Answer 5

I come with another pseudo options that allows to cut corners and allow to see main background behind: DEMO
Borders can be done too : DEMO with borders
The method is to draw background-color from box-shadow on rotated pseudo-elements wich basic border triangle cannot achieve. Pseudo element can take almost any shapes from radius and transform ... if that gives some ideas :)