Add grey border to images

Hi,

Please can someone assist me with some custom code to add thin grey borders to the two images without any padding (as per the attached screenshot) on the page below: 

https://www.sigmascreed.co.uk/screed-guides

Many thanks,

Alex

If you want to target these 2 items specifically, then you can use the below code.

div#yui_3_17_2_1_1684346865743_69, div#yui_3_17_2_1_1684346865743_95 {
    border: 2px solid #000;

}

If you want to add it to any and all images on the site, then you can use this...

.sqs-image-content {

   border: 2px solid #000;

}