You could also use the below which will give you shadow box outlines so they look like cards:
/* List Cards - Styles the list items in a specific Knack view */
#view_xxx .kn-list-item-container {
border: solid 1px #2480CE; /* Adds a solid 1px blue border (#2480CE) around each list item */
/* Adds a subtle shadow effect to give a raised appearance */
-webkit-box-shadow: -1px 2px 5px 5px rgba(163,163,163,0.33); /* For WebKit browsers (Safari, Chrome) */
-moz-box-shadow: -1px 2px 5px 5px rgba(163,163,163,0.33); /* For Mozilla browsers (Firefox) */
box-shadow: -1px 2px 5px 5px rgba(163,163,163,0.33); /* Standard CSS property */
margin-top: 20px; /* Adds 20px space above each list item to separate them */
border-radius: 1em; /* Rounds the corners of the list item (1em = relative to font size) */
padding-bottom: 30px; /* Adds 30px of space at the bottom inside the list item */
}