Don’t Use height or width for img in Responsive Layouts

When you add an img to a page, you normally enter the width height of the image to your HTML markup. If you want your image to be responsive, you’re not supposed to do that anymore.
As mentioned before, you need to forget about the height and width of the image you’re using and so your HTML code would look like the following:

<img src=”image-source” alt=”image-alt-text”>

Next step in CSS:

img { 
max-width: 100%; 
height: auto; 
}

With the CSS rules defined for the image, the image will scale up and down always matching your viewport proportionally.