## Task
We have a company website with contact information in the header section. Your task is to implement a color change when a user hovers over the links in the header section.

Steps:
1. Select all `a` elements with the `header-link` class.
2. Use the appropriate pseudo-class for the hover effect.
3. Apply the `color` property with the value `blue` when the links are hovered.

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- Use the `.` and the class name to select an element by its class name.
- Use the `:hover` pseudo-class to react on mouse cursor hover.

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Introduction to CSS (Cascading Style Sheets), which is a styling language used to enhance the look and feel of web pages. We will cover how to deal with fonts, element positioning, colors, and other decorative effects.

Basic CSS concepts and rules to add styles to the web page.

Set of CSS properties that are used to style the text content of HTML elements.

Concept of arranging elements according to the box model, which describes the layout and spacing of all elements.

Method of arranging the set of elements in rows and columns.

Create visually stunning and interactive web designs by using advanced CSS techniques for adding decorative elements.

CSS Fundamentals

Challenge: User Action Pseudo-Classes

Task