Responsive web design makes your web page look good on all devices.Responsive web design uses only HTML and CSS. Responsive web design is not a program or a JavaScript. Web pages can be viewed using many different devices: desktops, tablets, and phones. Your web page should look good, and be easy to use, regardless of the device.

CSS is important because it allows web designers, developer, bloggers, and so forth to make our websites unique and attractive. CSS gives us the opportunity to play with a page layout, adjust colors and fonts, add effects to images, etc