.book-spread-preview{display:flex;align-items:center;justify-content:center;width:100%;perspective-origin:center center}.spread-3d-container{position:relative;transform-style:preserve-3d;transition:transform .3s ease-out;width:100%;max-width:1000px}.spread-3d-container:hover{transform:rotateX(3deg) scale(1.01)}.spread-drop-shadow{position:absolute;top:8px;right:8px;bottom:8px;left:8px;background:transparent;border-radius:4px;box-shadow:0 20px 60px #00000026,0 10px 30px #0000001a,0 5px 15px #00000014;transform:translateZ(-20px);z-index:-1}.spread-content{position:relative;display:flex;width:100%;background:#f5f3ef;border-radius:2px;overflow:hidden;box-shadow:0 1px 3px #0000001a,inset 0 0 0 1px #0000000d}.spread-page{position:relative;flex:1;overflow:hidden}.paper-base{position:absolute;top:0;right:0;bottom:0;left:0;z-index:1}.paper-noise{position:absolute;top:0;right:0;bottom:0;left:0;background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");background-repeat:repeat;pointer-events:none;mix-blend-mode:overlay}.content-canvas-container{position:absolute;top:0;right:0;bottom:0;left:0;z-index:2;display:flex;align-items:center;justify-content:center}.content-canvas{width:100%;height:100%;display:block;mix-blend-mode:multiply}.lighting-overlay{position:absolute;top:0;right:0;bottom:0;left:0;z-index:3;pointer-events:none}.spine-shadow{position:absolute;top:0;bottom:0;width:40%;pointer-events:none}.spine-shadow--left{right:0;background:linear-gradient(to left,rgba(0,0,0,.08) 0%,rgba(0,0,0,.03) 20%,transparent 60%)}.spine-shadow--right{left:0;background:linear-gradient(to right,rgba(0,0,0,.08) 0%,rgba(0,0,0,.03) 20%,transparent 60%)}.edge-highlight{position:absolute;top:0;bottom:0;width:3%;pointer-events:none}.edge-highlight--left{left:0;background:linear-gradient(to right,rgba(255,255,255,.4) 0%,rgba(255,255,255,.1) 50%,transparent 100%)}.edge-highlight--right{right:0;background:linear-gradient(to left,rgba(255,255,255,.4) 0%,rgba(255,255,255,.1) 50%,transparent 100%)}.vignette{position:absolute;top:0;right:0;bottom:0;left:0;background:radial-gradient(ellipse at center,transparent 50%,rgba(0,0,0,.02) 80%,rgba(0,0,0,.06) 100%);pointer-events:none}.page-footer{position:absolute;bottom:0;left:0;right:0;height:5%;pointer-events:none}.spine-binding{position:relative;width:2px;flex-shrink:0;background:linear-gradient(to bottom,#00000008,#00000014,#00000008);z-index:4}.spine-line{position:absolute;top:5%;bottom:5%;left:50%;width:1px;background:linear-gradient(to bottom,transparent 0%,rgba(0,0,0,.1) 20%,rgba(0,0,0,.15) 50%,rgba(0,0,0,.1) 80%,transparent 100%);transform:translate(-50%)}.book-edge{position:absolute;background:linear-gradient(to bottom,#f0ede6,#e8e4db,#ddd9cf);transform-style:preserve-3d;z-index:-1}.book-edge--left{left:0;top:0;bottom:0;width:6px;transform:rotateY(-90deg) translateZ(3px);background:linear-gradient(to right,#d5d0c5,#e0dbd0,#eae5da)}.book-edge--right{right:0;top:0;bottom:0;width:6px;transform:rotateY(90deg) translateZ(3px);background:linear-gradient(to left,#d5d0c5,#e0dbd0,#eae5da)}.book-edge--bottom{left:0;right:0;bottom:0;height:6px;transform:rotateX(90deg) translateZ(3px);background:linear-gradient(to top,#c8c3b8,#d8d3c8,#e5e0d5)}.spread-page .content-canvas-container:empty:before{content:"";position:absolute;top:10%;right:10%;bottom:10%;left:10%;border:2px dashed rgba(0,0,0,.1);border-radius:4px}@media (max-width: 768px){.spread-3d-container:hover{transform:rotateX(3deg) scale(1.02)}.spread-drop-shadow{box-shadow:0 10px 30px #0000001f,0 5px 15px #00000014}.book-edge{display:none}}@keyframes pageEnter{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}@keyframes pageCurl{0%{transform:perspective(1000px) rotateY(0)}to{transform:perspective(1000px) rotateY(-20deg)}}.spread-content{animation:pageEnter .4s ease-out}@media print{.book-spread-preview{perspective:none}.spread-3d-container{transform:none!important}.spread-drop-shadow,.book-edge{display:none}.content-canvas{mix-blend-mode:normal}}.realistic-book-preview{position:fixed;top:0;right:0;bottom:0;left:0;z-index:9999;display:flex;flex-direction:column;background:linear-gradient(135deg,#1a1a1a,#0d0d0d);overflow:hidden}.preview-backdrop{position:absolute;top:0;right:0;bottom:0;left:0;background:#000000d9;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);z-index:-1}.preview-header{display:flex;align-items:center;justify-content:space-between;padding:16px 24px;background:#0006;border-bottom:1px solid rgba(255,255,255,.1);z-index:10}.preview-title{font-size:18px;font-weight:600;color:#fff;letter-spacing:.5px}.preview-controls{display:flex;align-items:center;gap:16px}.page-indicator{font-size:14px;color:#ffffffb3}.control-btn{display:flex;align-items:center;justify-content:center;width:40px;height:40px;border-radius:8px;background:#ffffff1a;border:1px solid rgba(255,255,255,.15);color:#fff;cursor:pointer;transition:all .2s ease}.control-btn:hover{background:#fff3;transform:scale(1.05)}.close-btn:hover{background:#ef4444cc}.preview-content{flex:1;display:flex;align-items:center;justify-content:center;padding:24px;gap:24px}.nav-btn{display:flex;align-items:center;justify-content:center;width:56px;height:56px;border-radius:50%;background:#ffffff1a;border:1px solid rgba(255,255,255,.2);color:#fff;cursor:pointer;transition:all .3s ease;flex-shrink:0}.nav-btn:hover:not(:disabled){background:#fff3;transform:scale(1.1);box-shadow:0 0 20px #fff3}.nav-btn:disabled{opacity:.3;cursor:not-allowed}.book-container{perspective:2500px;display:flex;align-items:center;justify-content:center;flex:1;max-width:85vw;max-height:80vh}.book-flipbook{box-shadow:0 30px 80px #0009,0 15px 40px #0006,0 5px 20px #0000004d;border-radius:0 6px 6px 0}.book-page{position:relative;background:linear-gradient(135deg,#faf8f5,#f5f2ed,#f0ede6);overflow:hidden;box-sizing:border-box}.book-page[data-density=hard]{background:linear-gradient(135deg,#2c3e50,#1a252f)}.book-page[data-density=hard] .page-paper-texture{display:none}.page-paper-texture{position:absolute;top:0;right:0;bottom:0;left:0;background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");opacity:.06;mix-blend-mode:overlay;pointer-events:none}.page-content{position:absolute;top:0;right:0;bottom:0;left:0;padding:8px}.page-slot{position:absolute;overflow:hidden;background:#e5e5e5}.slot-image{width:100%;height:100%;-o-object-fit:cover;object-fit:cover;mix-blend-mode:multiply}.slot-empty{width:100%;height:100%;background:linear-gradient(135deg,#e8e8e8,#d8d8d8)}.page-text-zone,.page-text-box{position:absolute;overflow:hidden;word-wrap:break-word;white-space:pre-wrap;padding:4px;box-sizing:border-box}.page-text-zone{display:flex;align-items:flex-start}.page-text-box{display:flex;align-items:center}.page-empty{display:flex;align-items:center;justify-content:center;height:100%;color:#fffc}.cover-text{font-size:28px;font-weight:300;letter-spacing:4px;text-transform:uppercase;text-shadow:0 2px 4px rgba(0,0,0,.3)}.cover-text.back{font-size:18px;letter-spacing:2px;opacity:.7}.page-number{position:absolute;bottom:16px;font-size:12px;color:#0006;font-weight:400}.page-number--left{left:16px}.page-number--right{right:16px}.page-spine-shadow{position:absolute;top:0;bottom:0;width:40%;pointer-events:none}.page-spine-shadow--left{right:0;background:linear-gradient(to left,rgba(0,0,0,.06) 0%,rgba(0,0,0,.02) 30%,transparent 100%)}.page-spine-shadow--right{left:0;background:linear-gradient(to right,rgba(0,0,0,.06) 0%,rgba(0,0,0,.02) 30%,transparent 100%)}.page-edge-highlight{position:absolute;top:0;bottom:0;width:2%;pointer-events:none}.page-edge-highlight--left{left:0;background:linear-gradient(to right,rgba(255,255,255,.3) 0%,transparent 100%)}.page-edge-highlight--right{right:0;background:linear-gradient(to left,rgba(255,255,255,.3) 0%,transparent 100%)}.preview-footer{padding:16px 24px;background:#0006;border-top:1px solid rgba(255,255,255,.1)}.thumbnail-bar{display:flex;justify-content:center;gap:8px;overflow-x:auto;padding:4px}.thumbnail-btn{display:flex;flex-direction:column;align-items:center;gap:4px;padding:8px;border-radius:8px;background:transparent;border:2px solid transparent;cursor:pointer;transition:all .2s ease;flex-shrink:0}.thumbnail-btn:hover{background:#ffffff1a}.thumbnail-btn--active{border-color:#fff;background:#ffffff26;transform:scale(1.1)}.thumbnail-spread{display:flex;width:48px;height:32px;border-radius:2px;overflow:hidden;box-shadow:0 2px 8px #0000004d}.thumbnail-page{flex:1;background:linear-gradient(135deg,#f5f5f5,#e8e8e8)}.thumbnail-spine{width:1px;background:#0003}.thumbnail-label{font-size:10px;color:#fff9}.thumbnail-btn--active .thumbnail-label{color:#fff}.preview-instructions{position:absolute;bottom:100px;left:50%;transform:translate(-50%);padding:12px 24px;background:#000000b3;border-radius:24px;color:#fffc;font-size:13px;pointer-events:none;animation:fadeInOut 5s ease-in-out forwards;white-space:nowrap}@keyframes fadeInOut{0%{opacity:0;transform:translate(-50%) translateY(10px)}10%{opacity:1;transform:translate(-50%) translateY(0)}80%{opacity:1}to{opacity:0}}@media (max-width: 768px){.preview-header{padding:12px 16px}.preview-title{font-size:14px}.preview-content{padding:12px;gap:8px}.nav-btn{width:40px;height:40px}.preview-footer{padding:12px 16px}.preview-instructions{font-size:11px;padding:8px 16px;bottom:80px}}.realistic-book-preview:fullscreen{background:#000}.realistic-book-preview:fullscreen .book-container{transform:scale(1.1)}@media print{.realistic-book-preview{display:none}}