How to Override width and height HTML attributes with CSS

By  on  

One of the HTML elements that frequently comes into collision with CSS is the img element. As we learned in Request Metrics' Fixing Cumulative Layout Shift Problems on DavidWalshBlog article, providing image dimensions within the image tag will help to improve your website's score. But in a world where responsive design is king, we need CSS and HTML to work together.

Most responsive design style adjustments are done via max-width values, but when you provide a height value to your image, you can get a distorted image. The goal should always be a display images in relative dimensions. So how do we ensure the height attribute doesn't conflict with max-width values?

The answer is as easy as height: auto!

/* assuming any media query */
img {
  /* Ensure the image doesn't go offscreen */
  max-width: 500px;
  /* Ensure the image height is responsive regardless of HTML attribute */
  height: auto;
}

The dance to please users and search engines is always a fun balance. CSS and HTML were never meant to conflict but in some cases they do. Use this code to optimize for both users and search engines!

Recent Features

  • By
    Animated 3D Flipping Menu with CSS

    CSS animations aren't just for basic fades or sliding elements anymore -- CSS animations are capable of much more.  I've showed you how you can create an exploding logo (applied with JavaScript, but all animation is CSS), an animated Photo Stack, a sweet...

  • By
    Creating Scrolling Parallax Effects with CSS

    Introduction For quite a long time now websites with the so called "parallax" effect have been really popular. In case you have not heard of this effect, it basically includes different layers of images that are moving in different directions or with different speed. This leads to a...

Incredible Demos

  • By
    MooTools Link Fading

    We all know that we can set a different link color (among other properties) on the hover event, but why not show a little bit more dynamism by making the original color fade to the next? Using MooTools 1.2, you can achieve that effect. The MooTools...

  • By
    Six Degrees of Kevin Bacon Using MooTools 1.2

    As you can probably tell, I try to mix some fun in with my MooTools madness but I also try to make my examples as practical as possible. Well...this may not be one of those times. I love movies and useless movie trivia so naturally I'm...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!