/* Adapted from ThreeUI Community 1.2.0 Bestsellers Book Showcase, MIT ©2026 Meng To.
   Original: /3d-assets/bestseller-books. Geometry, depth, hinged cover and page fan retained.
   Kejian replaces artwork, palette and copy; no original cover videos or private assets. */
.threeui-book-scene{position:relative;width:100%;height:520px;perspective:1400px;isolation:isolate;transform-style:flat}
.threeui-book-scene .book-card{--r:0deg;--yaw:0deg;--hover-y:0px;position:absolute;top:14%;left:53%;width:42%;aspect-ratio:.672/1;padding:0;background:transparent;transform:translate3d(-50%,var(--hover-y),0) rotate(var(--r)) rotateY(var(--yaw));transform-style:preserve-3d;transition:transform .8s var(--ease);z-index:3;cursor:pointer;text-align:left}
.threeui-book-scene .book-card:nth-child(1){--r:-14deg;--yaw:-12deg;--cover-color:#d9d9bc;--foil:#4b634b;left:22%;top:30%;width:34%;z-index:1}
.threeui-book-scene .book-card:nth-child(2){--r:-5deg;--yaw:-6deg;--cover-color:#174f3d;--foil:#dfc68f}
.threeui-book-scene .book-card:nth-child(3){--r:16deg;--yaw:10deg;--cover-color:#bba783;--foil:#3b4938;left:82%;top:31%;width:34%;z-index:2}
.threeui-book-scene .book-card:hover,.threeui-book-scene .book-card:focus-visible{--hover-y:-16px;z-index:5}
.threeui-book-scene .book{position:relative;display:block;width:100%;height:100%;transform-style:preserve-3d;transition:transform .8s var(--ease)}
.threeui-book-scene :is(.book-back,.page-block,.page-fan,.front-cover,.book-shadow){position:absolute;inset:0;border-radius:4px 8px 8px 4px}
.threeui-book-scene .book-shadow{z-index:-2;inset:5% -4% -2% 4%;background:#233b2440;filter:blur(22px);opacity:.6;transform:translate3d(18px,28px,-60px)}
.threeui-book-scene .book-back{z-index:0;background:var(--cover-color);box-shadow:0 18px 30px #19362524;transform:translate3d(7px,1px,-26px)}
.threeui-book-scene .page-block{z-index:1;inset:1.7% 1.4% 1.7% 3.8%;border:1px solid #b5ab93;background:#ece7d7 url('./page-edges.svg');box-shadow:7px 5px 16px #23301b21;transform:translate3d(7px,1px,-12px)}
.threeui-book-scene .page-block::after{content:'';position:absolute;right:-7px;top:0;width:8px;height:100%;background:#e4ddc9 url('./page-edges.svg');transform:skewY(-2deg);border-radius:0 4px 4px 0}
.threeui-book-scene .page-fan{z-index:2;inset:2.4% 2% 2.4% 4.3%;pointer-events:none;transform-style:preserve-3d}
.threeui-book-scene .page-fan i{position:absolute;inset:0;display:block;border:1px solid #cabfa6;border-radius:4px;background:#f7f3e6;opacity:0;transform-origin:1.5% center;transition:opacity .7s var(--motion-o),transform 1.2s var(--motion-e)}
.threeui-book-scene .front-cover{z-index:3;overflow:hidden;background:var(--cover-color);box-shadow:0 25px 38px #20351c26,inset -8px 0 16px #0000000a,inset 4px 0 8px #ffffff12;transform:translate3d(0,0,12px);transform-origin:1.5% center;transform-style:preserve-3d;transition:transform 1.2s var(--motion-e)}
.threeui-book-scene .front-cover::before{content:'';position:absolute;left:4%;top:0;width:1px;height:100%;background:#ffffff26}
.threeui-book-scene .cover-copy{position:absolute;inset:24px 24px 24px 32px;display:flex;flex-direction:column;align-items:flex-start;color:var(--foil)}
.threeui-book-scene .cover-brand{display:flex;align-items:center;gap:8px;color:inherit}.cover-brand img{width:32px;height:32px;border-radius:4px}.threeui-book-scene .cover-title{margin-top:24px;letter-spacing:.04em}.threeui-book-scene .cover-symbol{margin:auto;display:grid;place-items:center;border:1px solid currentColor;border-radius:50%;width:80px;height:80px;opacity:.7}.cover-symbol .icon{width:40px;height:40px}.threeui-book-scene .cover-bottom{padding-top:16px;opacity:.8}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-copy{inset:16px 16px 16px 24px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-brand img{display:none}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-title{font-size:24px;line-height:32px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-symbol{width:64px;height:64px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-bottom{font-size:12px;line-height:16px}
.threeui-book-scene .book-card.is-open .front-cover,.threeui-book-scene .book-card:hover .front-cover,.threeui-book-scene .book-card:focus-visible .front-cover{transform:translate3d(0,0,18px) rotateY(-29deg)}
.threeui-book-scene .book-card.is-open .page-fan i,.threeui-book-scene .book-card:hover .page-fan i{opacity:1}.threeui-book-scene .book-card.is-open .page-fan i:nth-child(1),.threeui-book-scene .book-card:hover .page-fan i:nth-child(1){transform:translate3d(0,0,10px) rotateY(-4deg)}.threeui-book-scene .book-card.is-open .page-fan i:nth-child(2),.threeui-book-scene .book-card:hover .page-fan i:nth-child(2){transform:translate3d(0,0,11px) rotateY(-8deg)}.threeui-book-scene .book-card.is-open .page-fan i:nth-child(3),.threeui-book-scene .book-card:hover .page-fan i:nth-child(3){transform:translate3d(0,0,12px) rotateY(-12deg)}.threeui-book-scene .book-card.is-open .page-fan i:nth-child(4),.threeui-book-scene .book-card:hover .page-fan i:nth-child(4){transform:translate3d(0,0,13px) rotateY(-16deg)}
.book-scene-foot{position:absolute;bottom:0;left:0;right:0;display:flex;justify-content:center;align-items:center;gap:8px;color:var(--muted)}
@media(max-width:1000px){.threeui-book-scene{width:min(560px,100%);height:480px;margin:auto}}
@media(max-width:600px){.threeui-book-scene{height:380px;max-width:400px}.threeui-book-scene .cover-copy{inset:16px 12px 16px 16px}.threeui-book-scene .cover-brand img{width:24px;height:24px}.threeui-book-scene .cover-title{font-size:24px;line-height:32px;margin-top:16px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-title{font-size:18px;line-height:28px}.threeui-book-scene .cover-symbol,.threeui-book-scene .book-card:not(:nth-child(2)) .cover-symbol{width:48px;height:48px}.cover-symbol .icon{width:24px;height:24px}.threeui-book-scene .cover-bottom{font-size:12px;line-height:16px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-copy{inset:12px 8px 12px 16px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-brand{font-size:12px;line-height:16px}}
@media(max-width:600px){.book-card:nth-child(1){left:23%;width:32%}.book-card:nth-child(3){left:78%;width:32%}.book-card:not(:nth-child(2)) .cover-bottom{display:none}}
/* English teacher edition: same ThreeUI page/cover geometry, new book jackets. */
.threeui-book-scene{height:536px}.threeui-book-scene .book-card:nth-child(1){--cover-color:#708794;--foil:#f0e9d5;left:23%;top:27%;width:32%;--r:-13deg}.threeui-book-scene .book-card:nth-child(2){--cover-color:#234f40;--foil:#e0cda0;left:52%;top:10%;width:44%;--r:-7deg}.threeui-book-scene .book-card:nth-child(3){--cover-color:#b56f54;--foil:#fff1d5;left:78%;top:28%;width:32%;--r:13deg}.threeui-book-scene .cover-copy{inset:24px 24px 24px 32px}.threeui-book-scene .cover-title{letter-spacing:-.02em;margin-top:32px}.threeui-book-scene .cover-brand{letter-spacing:.05em}.cover-rule{display:block;width:32px;height:1px;background:currentColor;margin-top:24px;opacity:.5}.threeui-book-scene .cover-symbol{border-radius:0;border:0;width:64px;height:64px;opacity:.7}.threeui-book-scene .cover-symbol .icon{width:48px;height:48px}.threeui-book-scene .cover-bottom{opacity:.85}.threeui-book-scene .cover-bottom>.caption-5{display:block;margin-top:8px;font-size:12px;line-height:16px;letter-spacing:.03em}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-title{font-size:24px;line-height:32px;letter-spacing:-.03em}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-symbol{width:48px;height:48px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-symbol .icon{width:32px;height:32px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-bottom>.caption-5{display:none}.page-print{display:block;padding:24px 16px;color:#748369;transform:translateZ(1px)}.threeui-book-scene .book-card.is-open .front-cover{transform:translate3d(0,0,18px) rotateY(-42deg)}
@media(max-width:1000px){.threeui-book-scene{height:520px}}
@media(max-width:600px){.threeui-book-scene{height:400px}.threeui-book-scene .book-card:nth-child(2){left:50%;top:12%;width:44%}.threeui-book-scene .book-card:nth-child(1){left:23%;top:28%;width:30%}.threeui-book-scene .book-card:nth-child(3){left:77%;top:28%;width:30%}.threeui-book-scene .cover-copy{inset:16px 12px 16px 16px}.threeui-book-scene .cover-title{font-size:24px;line-height:32px;margin-top:16px}.threeui-book-scene .book-card:not(:nth-child(2)) .cover-title{font-size:18px;line-height:28px}.threeui-book-scene .cover-symbol{width:40px;height:40px}.threeui-book-scene .cover-symbol .icon{width:32px;height:32px}.cover-rule{margin-top:16px;width:24px}.threeui-book-scene .cover-bottom{font-size:12px;line-height:16px}.threeui-book-scene .cover-bottom>.caption-5{font-size:12px;line-height:16px;letter-spacing:0}.threeui-book-scene .cover-brand{font-size:12px;line-height:16px;letter-spacing:0}.threeui-book-scene .cover-title{font-size:24px;line-height:32px}.page-print{padding:16px;font-size:12px;line-height:16px}}