Example
SASS gives you the ability to omit any parameter except the ones you want to overwrite of course. Let's take again the default-box example:
@mixin default-box ($color: red, $borderColor: blue) {
color: $color;
border: 1px solid $borderColor;
clear: both;
display: block;
margin: 5px 0;
padding: 5px 10px;
}
Here we'll now call the mixin having overwritten the second parameter
footer, header{ @include default-box ($borderColor: #ccc); }
the value of $borderColor is #ccc, while $color stays red
