.simplecheckout .simplecheckout-block-content .radio input[type="radio"]:checked  {
    background-image: none; !important;
}

.simplecheckout .simplecheckout-block-content .radio input[type="radio"][checked] {
    background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADAAAAAwCAYAAABXAvmHAAAAAXNSR0IArs4c6QAAAERlWElmTU0AKgAAAAgAAYdpAAQAAAABAAAAGgAAAAAAA6ABAAMAAAABAAEAAKACAAQAAAABAAAAMKADAAQAAAABAAAAMAAAAADbN2wMAAACyUlEQVRoBe2YPW/TQBjHn7ODU8lplQUJJAYkQAwM8AVYWFCpeCkSGwJGlo68LAiDmFgrFqYiNtKmdCli40vAhBA7Q9ukgdaV73geG7e+xJecHSc20t3ie/Pd7//3k+euBTDFOGAcMA4YB4wD/7EDrMrsF7w7TpfPvhQc7gPjgoH9ftbuPPvqtfyYuxZXqvY8u7RU3wm6axbAAgttxhqIxyhIYOVpzEu9lSvkvN/c/WCBtdAPJwS/l+yrnIAwbIJGC4DdSILGdSYYfYHDUikBUdi4bRV8SG3Bu0N6rFRGAMHvNSnmB8MmBkbrPzlbjRdxm552slFWncLmTx1aDKzrSgYOn+0aX/zx+u1+ck7paXRUzIewCG8d47d+eit7SXiqlypgXPhSBRQBX5qAouBLEVAkPAmQrhLh4tx9JQTcBWExhjnX2XKff19eln759GKeQqmyG/zGPC+uqd6nVFnvuIu6e0rnQBfhEfwRprOTeP84AQKe7Dd767SxakPdflrDb2rAb+vD096SgND5PiJMU/P+XG/jtPdgpm9Iu0lfFu82eD1QOw+U521+W9f5eHNJAIVNPCA9LbjKD6yPeUT8i/lVzNhDDylVnpc4UhqSAAyblZQ5UReKCAKrnSWcopifWx8GH14POu7NtENKyZIYkAQ4265HCybGpWoYThjHOiImFfMSEDYGQqaIT17EGv2gqvaAAJo4DsA476ogh/WnCsgrYtrwxKkUkFWECz3eDRoTyzbEk1aGCqAX6MdIhxlOnE9bIOpjm9FTnefDEzbjIaXe72hkpACaqhUaR2sO1obc5wcnZ+vR+ovs15dvwakr59Z84VzCqDufaYsJwhOHlgCamEvEhOEzCcgsYgrwmQVoi5gSfC4BI0VMET63gFjE8YuX28HMQU0AP4NX5V0G7I2z4z7s/9cHzTfFOGAcMA4YB4wDxoEUB/4CTYGNlObVZDQAAAAASUVORK5CYII=');
    background-size: contain;
    background-repeat: no-repeat;
}