body   {background-color:#FFFFFF; color: black; position: relative;
    font-family: verdana;
    font-size: 12px;
    margin: 2px;
    padding: 4px;
    min-width:640px; /* suppose you want minimun width of 640px */
    width: auto !important;  /* Firefox will set width as auto */
    width:640px;             /* As IE ignores !important it will set width as 640px; */
    }

#cards tr:nth-child(even){background-color: #f2f2f2;}

#cards tr:hover {background-color: #ddd;}