Using Salesforce Styles

Many Visualforce components already have the look and feel of the same components in Salesforce, such as the related list in a detail page, or a section header. Part of the styling of these components, including the component’s color scheme, is based on the tab on which the component appears. You can specify the tab style that should be used to style a component by associating a page with a standard controller, or by setting the tabStyle attribute on the <apex:page> or <apex:pageBlock> tags.