Add their one line of JavaScript to your global JavaScript file, then use a class selector to specify different CSS options based on the browser. Here’s an example in CSS that will change the color of a rectangle based on the browser you’re using. Brilliant!

.ie .example {
  background-color: yellow
}
.ie7 .example {
  background-color: orange
}
.gecko .example {
  background-color: gray
}
.win.gecko .example {
  background-color: red
}
.linux.gecko .example {
  background-color: pink
}
.opera .example {
  background-color: green
}
.konqueror .example {
  background-color: blue
}
.webkit .example {
  background-color: black
}
.example {
  width: 100px;
  height: 100px;
}
.no_js { display: block }
.has_js { display: none }
.js .no_js { display: none }
.js .has_js { display: block }