CSS CLASSES AND IDS

- The * selector selects all elements.
- The * selector can also select all elements inside another element (See "More Examples").
- ID

• The id selector uses the id attribute of an HTML element to select a specific element.
• An id should be unique within a page, so the id selector is used if you want to select a single, unique element.
• To select an element with a specific id, write a hash character, followed by the id of the element.

- Class

• The class selector selects elements with a specific class attribute.
• To select elements with a specific class, write a period character, followed by the name of the class

- Pseudo-classes

• a:link (unvisited link)
• a:visited (visited link)
• a:hover (mouse over link)
• a:active (selected link)

Note: a:hover MUST come after a:link and a:visited in the CSS definition in order to be effective! a:active MUST come after a:hover in the CSS definition in order to be effective! Pseudo-class names are not case-sensitive.

 The :first-child pseudo-class matches a specified element that is the first child of another element.