Help needed with a HTML Block not displaying correctly

Hi Community,

I am trying to add a HTML block to display 3 images (one nest to the other, no space between them or padding). And need them to display the same on mobile and desktop.

I converted my code into XHTML and pasted it in the block. The images appear now one on top of the other in the builder and when I send a test email they won’t display at all. Can anyone help? the XHTML code is below

<![CDATA[ { box-sizing: border-box; }

.column {
float: left;
width: 33.33%;
padding: 0px;

.row::after {
content: “”;
clear: both;
display: table;

Shop Nexgard Spectra
Shop Seresto