.book-3d-container{perspective:1100px;justify-content:center;align-items:center;display:flex}.book-3d{transform-style:preserve-3d;transition:transform 1s;position:relative}.book-3d-spine{background:linear-gradient(90deg,#fff 0%,#f9f9f9 5%,#fff 10%,#f9f9f9 15%,#fff 20%,#f9f9f9 25%,#fff 30%,#f9f9f9 35%,#fff 40%,#f9f9f9 45%,#fff 50%,#f9f9f9 55%,#fff 60%,#f9f9f9 65%,#fff 70%,#f9f9f9 75%,#fff 80%,#f9f9f9 85%,#fff 90%,#f9f9f9 95%,#fff 100%);position:absolute;top:4px;left:0}