Triangle from pseudo element
by aflynt
HTML
<div id="box"></div>
CSS
#box {
background: lightblue;
height: 6em;
position: relative;
width: 10em;
}
#box:before {
border-bottom: 40px solid transparent;
border-left: 40px solid transparent;
border-top: 40px solid green;
content: '';
height: 0;
position: absolute;
right: 0;
width: 0;
}
#box:after {
color: white;
content: '\2b';
position: absolute;
right: 8px;
top: 4px;
}
JavaScript
/*
#box builds the box
#box:before adds the green triangle
#box:aafter adds the plus sign
*/