Enlarge Services Thumbnails

Hello, I'd like the "services" 3 images to be bigger. To do so I added this code: } img.attachment-euphony-service.size-euphony-service.wp-post-image { width: 150px; } Though I think that is just displaying small images bigger, which is why they appear blurry. Can you help me fix the default width and size to be larger? https://ibb.co/P4pP1Mx