.flip-btn{position:relative;display:block;width:220px;height:60px;transform-style:preserve-3d;transform:perspective(1000px) rotateX(0deg);transition:1.5s;text-decoration:none}.flip-btn:hover{transform:perspective(1000px) rotateX(360deg)}.flip-btn span{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:#fff;border:2px solid #000;font-size:20px;font-weight:700;box-sizing:border-box;transition:.4s}.flip-btn:hover span{background:#2196f3;color:#fff}.flip-btn span:nth-child(1){transform:rotateX(0deg) translateZ(30px)}.flip-btn span:nth-child(2){transform:rotateX(90deg) translateZ(30px)}.flip-btn span:nth-child(3){transform:rotateX(180deg) translateZ(30px)}.flip-btn span:nth-child(4){transform:rotateX(270deg) translateZ(30px)}