[FIG(quote)[ [FIGCAPTION[ [1] [CITE[Opera Reader: Paging the Web]] ([TIME[2015-07-28 11:59:24 +09:00]] 版) ]FIGCAPTION] > The new at-rule – @-o-navigation – can look something like thhis: > @-o-navigation { > nav-up: -o-url-doc(/); > nav-down: url(a1.html); > nav-right: -o-link-rel(next); > nav-left: -o-go(back); > } > The four new properties are pretty self explanatory – nav-up is what you want to navigate to when the page is moved up, and so on. Let's now talk through the four different values that the properties can take: > -o-url-doc(path): The path specified is a relative path to the HTML document, for example / to go to the root document. > url(path): The path specified is a standard URL to a file, and can be of any type that url() normally accepts (for example in background-image: url();). > -o-link-rel(value): The value is a rel attribute value from a element. For example, when you specify next, the browser looks for a element in the , and then takes its href value as the document to navigate to. > -o-go(value): in this case, the value can be forward or back – these instruct the browser to go forward or back in its history. ]FIG]