:root{font-family:Arial,Helvetica,sans-serif;color:#24344c;background:#f8f3eb;--orange:#b64b08;--border:#e3d8c9}*{box-sizing:border-box}body{margin:0;min-height:100svh;display:flex;flex-direction:column;background:radial-gradient(ellipse at 50% 35%,#fffdfa 0%,#f5eee3 90%)}button,input{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #2772bd;outline-offset:4px}button:disabled{opacity:.35;cursor:default}.header{display:flex;justify-content:space-between;align-items:center;gap:18px;width:min(1140px,100%);margin:auto;padding:20px 30px 12px}.eyebrow{font-size:11px;letter-spacing:2px;font-weight:700;color:var(--orange);text-transform:uppercase}.header h1{font-size:23px;letter-spacing:-.5px;margin:5px 0 0}.actions{display:flex;gap:8px}.tool{border:1px solid var(--border);border-radius:12px;padding:11px 14px;background:#fffaf4;color:#24344c;font-size:13px;font-weight:600}.tool:hover{background:#fff}.main{flex:1;display:flex;flex-direction:column;align-items:center;width:100%;padding:8px 24px}.stage{display:grid;place-items:center;width:100%;height:calc(100svh - 222px);min-height:240px;max-height:900px;position:relative;perspective:2200px;touch-action:pan-y}.book{position:relative;width:100%;height:100%;filter:drop-shadow(0 14px 20px #44331e25)}.page,.leaf{position:absolute;inset:0;width:100%;height:100%;border-radius:3px;object-fit:contain;background:#fff}.leaf{pointer-events:none;backface-visibility:hidden;transform-origin:left center;box-shadow:4px 0 16px #33281d12;z-index:2}.hidden,[hidden]{display:none!important}.loading{position:absolute;background:#fff9f0;border-radius:16px;padding:20px;z-index:3;font-size:14px}.controls{width:min(850px,100%);display:flex;align-items:center;gap:22px;margin-top:20px}.nav{border:0;border-radius:14px;background:#fff;color:#24344c;min-height:46px;min-width:110px;font-size:14px;font-weight:700;box-shadow:0 2px 5px #50412f0a}.nav.next{background:var(--orange);color:#fff}.progress{flex:1;display:flex;flex-direction:column;gap:7px;min-width:0}.count{font-size:12px;color:#596779;display:flex;justify-content:space-between;align-items:center;font-variant-numeric:tabular-nums}.count button{border:0;background:none;color:var(--orange);padding:4px 0;font-size:12px;font-weight:700}input[type=range]{width:100%;accent-color:var(--orange);height:18px;margin:0}.hint{font-size:11px;color:#687582;margin:14px 0 0;text-align:center}.footer{padding:16px;text-align:center;font-size:11px;color:#697381}.footer a{color:inherit;text-decoration:none}.footer b{color:#9f430c}.toast{position:fixed;bottom:70px;left:50%;transform:translateX(-50%);background:#253b50;color:white;padding:12px 18px;border-radius:12px;max-width:90vw;font-size:13px;z-index:8}.dialog{border:0;border-radius:20px;padding:0;width:min(970px,95vw);max-height:90svh;box-shadow:0 20px 70px #1115;color:#24344c;background:#fffaf4}.dialog::backdrop{background:#182533b3}.dialog-head{display:flex;justify-content:space-between;align-items:center;padding:16px 22px;background:#fffaf4;position:sticky;top:0;z-index:2;border-bottom:1px solid var(--border)}.dialog-head h2{font-size:18px;margin:0}.close{border:0;background:#efe5d8;color:#24344c;border-radius:50%;width:36px;height:36px;font-size:24px}.thumbs{display:grid;grid-template-columns:repeat(auto-fit,minmax(145px,1fr));gap:18px;padding:20px}.thumb{border:2px solid transparent;border-radius:10px;background:#fff;padding:6px;color:#34455c;box-shadow:0 2px 6px #34221010}.thumb[aria-current=true]{border-color:var(--orange)}.thumb img{display:block;width:100%;height:118px;object-fit:contain}.thumb span{display:block;font-size:12px;padding:8px}.zoom-dialog{width:96vw;height:94svh;max-height:94svh}.zoom-scroll{overflow:auto;height:calc(94svh - 70px);background:#e8e2d9;padding:20px;overscroll-behavior:contain}.zoom-image{display:block;max-width:none;width:max(100%,1400px);height:auto;margin:auto}.zoom-title{font-size:13px!important}.reader-error{background:#fff;padding:20px;border:1px solid #b44;border-radius:12px;z-index:5;position:absolute;max-width:90%;text-align:center}.reader-error button{margin-top:12px}.reader-error p{margin:0}
@media(max-width:650px){.header{padding:14px 15px 10px;gap:10px}.header h1{font-size:18px}.eyebrow{font-size:9px;letter-spacing:1.3px}.actions{gap:5px}.tool{font-size:12px;padding:9px}.tool .wide{display:none}.main{padding:8px 10px;justify-content:center}.stage{height:min(calc(100svh - 250px),78vw);min-height:0}.controls{gap:10px;margin-top:16px}.nav{min-width:55px;padding:10px;font-size:19px}.nav .word{display:none}.count{font-size:11px}.footer{font-size:10px;padding:12px 8px}.hint{font-size:10px}.thumbs{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;padding:12px}.dialog-head{padding:12px 16px}.zoom-image{width:1200px}}@media(max-height:520px) and (orientation:landscape){.header{padding:8px 20px}.header h1{font-size:16px}.stage{height:calc(100svh - 155px);min-height:150px}.controls{margin-top:8px}.nav{min-height:34px}.hint{display:none}.footer{padding:8px}.tool{padding:8px}.eyebrow{font-size:9px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}

.header{width:min(1600px,100%)}.stage{max-width:1600px;perspective:2400px}.book.spread{isolation:isolate;transform-style:preserve-3d;perspective:2400px;background:#fff8ef;border-radius:7px;box-shadow:0 3px 0 #d4c9ba,0 5px 0 #eee5da,0 7px 0 #cfc2b1}.book.cover-only{transform:translateX(-25%);background:transparent;box-shadow:none}.book.cover-only:not(.turning) .spread-page.left,.book.cover-only:not(.turning) .spine{visibility:hidden}.book.cover-only .spread-page.right{border-radius:6px;box-shadow:0 5px 18px #30200e28}.spread-page{position:absolute;top:0;width:50%;height:100%;background:#fff;overflow:hidden}.spread-page.left{left:0;border-radius:6px 0 0 6px}.spread-page.right{right:0;border-radius:0 6px 6px 0}.spread-page img,.face img{display:block;width:100%;height:100%;object-fit:contain}.spread-page.blank,.face.blank{background:linear-gradient(90deg,#f7f0e6,#fffaf3)}.spine{position:absolute;left:calc(50% - 9px);width:18px;height:100%;background:linear-gradient(90deg,transparent,#281b0b22 45%,#281b0b42 50%,#281b0b18 55%,transparent);z-index:4;pointer-events:none}.turning-leaf{position:absolute;top:0;width:50%;height:100%;transform-style:preserve-3d;z-index:5;pointer-events:none;will-change:transform}.turning-leaf.forward{left:50%;transform-origin:left center}.turning-leaf.backward{left:0;transform-origin:right center}.face{position:absolute;inset:0;backface-visibility:hidden;-webkit-backface-visibility:hidden;background:white;overflow:hidden;box-shadow:0 5px 20px #30200e30}.face.back{transform:rotateY(180deg)}.face:after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,#30200e20,transparent 10%,transparent 70%,#30200e15);pointer-events:none}.zoom-spread{display:grid;grid-template-columns:1fr 1fr;width:max(100%,2400px);background:#fff;gap:3px}.zoom-spread img{width:100%;display:block}.zoom-title{font-size:13px}.book.turning .spine{opacity:.65}@media(max-width:650px){.header{flex-wrap:wrap;justify-content:center}.header>div:first-child{text-align:center;width:100%}.actions{justify-content:center}.actions .tool{min-width:42px}.stage{height:min(calc(100svh - 290px),39vw)}.main{justify-content:center}.hint{max-width:300px}.zoom-spread{width:2200px}}


/* Responsive additions to the original LearnYB pre-primary paper/leaf style. */
html,body{height:100%;height:100dvh;overflow:hidden}body{min-height:0}.header{flex:none;max-width:1500px;width:100%;padding:12px 24px 8px;margin:0 auto;min-height:78px}.header h1{font-size:22px}.eyebrow{letter-spacing:1px}.actions{flex-wrap:nowrap}.tool{min-height:44px;min-width:44px;font-size:13px;padding:10px 13px}.main{flex:1;min-height:0;padding:4px 24px max(8px,env(safe-area-inset-bottom));overflow:hidden}.stage{flex:1;min-height:0;max-height:none;height:auto;touch-action:pan-y pinch-zoom;max-width:1600px;perspective:2400px}.book.spread{position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);background:white}.book.spread.solo{box-shadow:0 3px 0 #d4c9ba,0 5px 0 #eee5da,0 7px 0 #cfc2b1}.book.spread.solo .spine{display:none}.book.spread.solo .spread-page{width:100%;left:0;right:auto;border-radius:4px}.book.spread.solo .spread-page.blank{display:none}.spread-page img,.face img{object-fit:contain;background:white}.spread-page.blank,.face.blank{background:white}.spread-page img{user-select:none;-webkit-user-select:none;-webkit-user-drag:none}.book.spread.single .turning-leaf{width:100%;left:0}.book.spread.single .turning-leaf.forward{transform-origin:left center}.book.spread.single .turning-leaf.backward{transform-origin:right center}.corner{position:absolute;bottom:0;width:12%;height:18%;min-width:44px;min-height:44px;max-width:95px;max-height:100px;border:0;background:transparent;padding:0;z-index:10;cursor:pointer;-webkit-tap-highlight-color:transparent}.corner-left{left:0}.corner-right{right:0}.corner:disabled{pointer-events:none}.corner:after{content:"";position:absolute;bottom:0;width:0;height:0;opacity:0;transition:opacity .15s;border-top:24px solid transparent}.corner-right:after{right:0;border-right:24px solid #fff7e4dd;filter:drop-shadow(-2px -2px 2px #0002)}.corner-left:after{left:0;border-left:24px solid #fff7e4dd;filter:drop-shadow(2px -2px 2px #0002)}.corner:hover:after,.corner:focus-visible:after{opacity:1}.book.turning .corner{pointer-events:none}.controls{flex:none;width:min(850px,100%);gap:20px;margin-top:12px}.nav{min-height:46px}.count{font-size:13px;justify-content:center;min-height:20px}input[type=range]{height:24px;min-height:24px}.hint{flex:none;font-size:12px;margin:8px 0 0}.dialog{max-height:90vh;max-height:90dvh}.dialog-head{top:0;gap:12px}.close{height:44px;width:44px;min-width:44px}.jump-form{display:flex;align-items:center;gap:10px;padding:16px 22px;position:sticky;top:77px;background:#fffaf4;z-index:1}.jump-form input{width:85px;min-height:44px;border:1px solid var(--border);border-radius:8px;padding:8px;font-size:16px}.thumb img{height:150px}.thumb span{font-size:13px}.thumb{min-height:44px}.chapter-list{padding:12px 20px 24px;display:grid;gap:8px}.chapter-link{display:flex;justify-content:space-between;gap:18px;text-align:left;align-items:center;border:1px solid var(--border);border-radius:10px;min-height:48px;padding:12px 16px;background:white;color:#24344c}.chapter-link span:last-child{font-size:13px;font-variant-numeric:tabular-nums;color:#596779;flex:none}.zoom-dialog{height:94vh;height:94dvh;max-height:94vh;max-height:94dvh}.zoom-scroll{height:calc(94vh - 77px);height:calc(94dvh - 77px);padding:12px;touch-action:pan-x pan-y pinch-zoom}.zoom-spread{grid-template-columns:repeat(2,minmax(0,1fr));gap:2px;width:max(100%,2400px)}.zoom-spread.one{grid-template-columns:1fr;width:max(100%,1500px)}.no-script{position:fixed;inset:25%;z-index:90;background:white;border-radius:20px;padding:30px}
@media(max-width:899px){.header{padding:10px 12px 7px;display:flex;flex-direction:column;gap:7px;min-height:94px}.header>div:first-child{width:100%;text-align:center}.header h1{font-size:18px;margin:3px 0 0;line-height:1.2}.eyebrow{font-size:10px}.actions{justify-content:center;gap:7px}.tool{font-size:12px;padding:8px 12px}.main{padding:4px 10px max(8px,env(safe-area-inset-bottom))}.stage{height:auto;min-height:0;max-height:none;flex:1}.controls{gap:12px;margin-top:10px}.nav{min-width:52px;padding:8px;font-size:22px;min-height:48px}.nav .word{display:none}.count{font-size:12px}.hint{font-size:10px;margin-top:7px}.thumbs{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;padding:12px}.thumb img{height:150px}.dialog-head{padding:10px 14px}.dialog-head h2{font-size:17px}.jump-form{top:65px;padding:12px 14px}.zoom-scroll{height:calc(94dvh - 65px)}.zoom-spread.one{width:1400px}.zoom-spread{width:2200px}}
@media(max-height:500px){.header{padding:5px 14px;min-height:48px;flex-direction:row;gap:12px}.header>div:first-child{text-align:left;width:auto}.header h1{font-size:16px;margin:1px 0}.eyebrow{font-size:9px}.tool{padding:5px 9px;min-height:40px}.controls{margin-top:6px}.nav{min-height:40px}.hint{display:none}.main{padding-bottom:5px}.header .actions{gap:5px}.stage{min-height:0}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}