To slim down the markup and make rounded corners faster and easier to understand we have used simple CSS class .addround
with default 5px border radius.

example:

.addround {
-webkit-border-radius:5px;
-khtml-border-radius:5px;
-moz-border-radius:5px;
border-radius:5px;
border:1px solid #999;
margin:5px;
}

To activate rounded corners for your module just go in template manager, tab Layout hover over the module position,
click on top left icon, select Round and hit save.

With small CSS change you can turn your default rounded corners in to this:

example:

.addround{
background: #40b1e2;
border:none;
box-shadow:inset 0px -100px 100px #329dcc;
color:#fff;
}
.addround .module_title,
.addround a{
color:#fff;
}
.addround a:hover,
.addround a:focus{
color:#121212;
}