How can I adjust image sized on the 'Abandoned browse/cart/checkout' email template?

This is from my abandoned browse email template. I would like to reduce the size, but there’s no edit feature and only I can put ‘abandoned browse’ as a whole. If there’s any code editor like other email notification template, I would like to edit the image size, but it’s not possible.
How do you adjust the image sizes?
If I can put abandoned cart/checkout/browse elements using ‘custom liquid/html’ section, which variables should I use? The contents should be generated dynamically for each customer, so I wonder if I can use these variables on the custom liquid section in the email template.

You can modify the style in the email editing code