We can make our data views more meaningful by setting up our data view to automatically use different styles in response to differing data values. This technique is known as conditional formatting.
Applying conditional formatting in SharePoint Designer requires us to use the XPath language. Don't worry though because SharePoint Designer makes this easy for us.
We would like to apply some conditional formatting to our data view so that it shows a differently formatted price for all wines that have a low number in stock.
We start this process by right-clicking on our data view and selecting Conditional Formatting from the shortcut menu. This will open up the Conditional Formatting task pane.

We then click on the data value that we would like to apply our conditional formatting to. We will select any of the prices in the data form. Below, I have selected the price of the most expensive wine, Chateau le Gay.

We then click the Create button in our Conditional Formatting...