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I have troubles regarding a slider I have on my website.
Currently it’s a slider with the <img> element. Problem I encounter now is that on mobile the large images get loaded as well. Now I want to load specific (smaller) images for mobile so that my website is faster on these devices.
A solution I had was using the media queries in combination with CSS background image. This is perfect to use because I can load the images with CSS and thus can use media queries to select the image based on screen size.
But the problem is is that I want to add the images to the SEO, they are essential for my website and I read everywhere that if you have such images, you need to use the <img> element. So that the SEO can work and include these images in the content. Also I cannot add ALT tags to background-image.
Another solution is rendering two sliders, one for mobile and one for desktop, and hiding the slider you don’t want to see. Problem I have with this solution is that both of the sliders need to render, thus decreasing performance.
Is there a solution that I’m missing here? In my understanding you cannot change images in a <img> element with CSS media queries.
2
Answers
You can use the
pictureelement. As the Mozilla Developer Network says, “[This element] serves as a container for zero or more elements and one element to provide versions of an image for different display device scenarios“. I think it does the trick. Here you are another good article that explains how to use this element to achieve the result you need with your responsive images.The
pictureelement is a really nice modern solution. But if you want something more cross-browser, consider an approach with JavaScript. My solution for some websites was using sets of images with regular suffixes, for exampleimage.jmg,image-medium.jpg,image-small.jpg, and a script checking the screen resolution. In the HTML only small images are included, but if the script finds the screen is big enough, it updates theirsrcwith corresponding suffixes.