

<img srcset="https://via.placeholder.com/320x240 320w,
        https://via.placeholder.com/480x360 480w,
        https://via.placeholder.com/640x480 640w, 
        https://via.placeholder.com/752x564 752w, 
        https://via.placeholder.com/960x720 960w" sizes="(max-width: 59em) 90vw, 
       (max-width: 105em) 50vw,
       960px" src="https://via.placeholder.com/960x720" alt="A referee uses the we.ref app during a football match at Broadwood Stadium near Glasgow">