This snippet--which could be improved on--allows you to easily display and hide the [BlueprintCSS](http://code.google.com/p/blueprintcss/) grid.
Put the following code inside the <head> element:
```javascript
```
Change selectorName or cssText, if needed. Next add the following link, for example, to the footer:
```javascript
Show grid
```
Now when you click the link, the grid will be displayed. Click again to hide it.
Note that this is a simple example of how to change a CSS style sheet dynamically with JavaScript. You can use it to change any selector at runtime.