:root{--navy:#162a43;--blue:#174c88;--edge:#e4e9f0;--paper:#f3f5f8;--page-ratio:0.75265}*{box-sizing:border-box}html,body{height:100%;margin:0}body{font-family:Arial,'Malgun Gothic','맑은 고딕',sans-serif;color:#223047;background:#edf1f6}button,input{font:inherit}button{cursor:pointer}button:disabled{opacity:.35;cursor:default}.app{height:100dvh;min-height:560px;display:flex;flex-direction:column}.header{height:68px;flex:none;background:var(--navy);color:white;display:flex;align-items:center;justify-content:space-between;padding:0 24px;gap:20px}.brand{display:flex;align-items:center;gap:12px}.brand-mark{width:40px;height:40px;border-radius:10px;background:#fff;color:#1761a2;display:flex;align-items:center;justify-content:center;font-size:20px;font-weight:800}.brand strong{font-size:18px;display:block;letter-spacing:-.7px}.brand small{font-size:11px;color:#bac9dd;display:block;margin-top:4px}.header-actions{display:flex;gap:8px}.topbtn{border:1px solid #60738c;background:transparent;color:#fff;text-decoration:none;border-radius:7px;padding:10px 13px;font-size:13px}.topbtn.primary{background:#2b76bb;border-color:#2b76bb}.layout{display:flex;flex:1;min-height:0}.sidebar{width:315px;flex:none;background:#fff;border-right:1px solid var(--edge);display:flex;min-height:0}.sidebar-buttons{background:#f3f6fa;border-right:1px solid var(--edge);width:93px;flex:none;display:flex;flex-direction:column;padding-top:8px;overflow:auto}.side-item{appearance:none;width:100%;min-height:67px;padding:7px 4px;color:#4f5f71;text-decoration:none;border:0;background:transparent;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:7px;font-size:11px}.side-item:hover,.side-item.active{background:#fff;color:#165ea2;box-shadow:inset 3px 0 #1e6dad}.side-item .ico{font-size:24px;font-family:Arial}.sidebar-content{flex:1;min-width:0;display:flex;flex-direction:column}.panel-title{height:52px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--edge);padding:0 18px}.panel-title b{font-size:14px}.panel-title button{display:none;background:none;border:0}.panel{overflow-y:auto;padding:12px 10px;flex:1}.toc-link{display:flex;justify-content:space-between;width:100%;gap:4px;text-align:left;border:0;background:transparent;padding:13px 10px;border-radius:7px;color:#35475a;font-size:12px;line-height:1.4}.toc-link span{color:#9aa5b5}.toc-link:hover,.toc-link.selected{background:#e8f2fb;color:#155a9b;font-weight:700}.thumb-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:11px;align-content:start}.thumb-button{padding:5px;border:2px solid transparent;border-radius:8px;background:transparent;font-size:11px;color:#526176}.thumb-button img{display:block;width:100%;border:1px solid #dce1e8;box-shadow:0 2px 6px #0002;margin-bottom:5px}.thumb-button.selected{border-color:#2276b7;background:#eaf4fd}.viewer{display:flex;flex:1;flex-direction:column;min-width:0;min-height:0}.viewer-top{height:48px;flex:none;border-bottom:1px solid #dde3ea;background:#fff;display:flex;align-items:center;justify-content:space-between;padding:0 22px}.viewer-title{font-size:13px;font-weight:700}.viewer-title span{color:#8994a2;font-weight:400}.zoom-controls{display:flex;align-items:center;gap:5px}.zoom-controls button{border:1px solid #dce2ea;background:#fff;border-radius:6px;padding:5px 9px;min-width:35px;color:#3d5167}.zoom-controls #zoomReset{min-width:67px;font-size:12px}.stage{position:relative;flex:1;min-height:0;overflow:auto;display:flex;align-items:center;justify-content:center;padding:24px 52px;background:radial-gradient(ellipse at center,#fafbfd 0%,#e5ebf2 100%)}.book{position:relative;flex:none;display:flex;align-items:stretch;filter:drop-shadow(0 9px 14px #20354c38);transform-style:preserve-3d;perspective:2000px}.book:not(.single):after{content:'';position:absolute;left:50%;top:0;bottom:0;width:4px;z-index:4;transform:translateX(-50%);background:linear-gradient(90deg,#0002,#fff5,#0002);pointer-events:none}.page{height:100%;position:relative;overflow:hidden;flex:1;background:#fff;user-select:none;cursor:pointer}.page img{width:100%;height:100%;display:block;object-fit:fill;pointer-events:none}.page.empty{background:transparent;cursor:default}.page.left:not(.empty){border-radius:3px 0 0 3px}.page.right:not(.empty){border-radius:0 3px 3px 0}.book.single .page{border-radius:3px}.nav-arrow{position:sticky;top:50%;z-index:8;flex:none;width:38px;height:58px;border:0;border-radius:8px;background:#fffdf0d9;box-shadow:0 2px 10px #0002;color:#294b6d;font-size:38px;line-height:1}.nav-arrow.prev{left:8px;margin-left:-44px;margin-right:6px}.nav-arrow.next{right:8px;margin-right:-44px;margin-left:6px}.controls{height:68px;background:#fff;border-top:1px solid var(--edge);display:flex;align-items:center;justify-content:space-between;padding:0 24px;gap:8px;flex:none}.controls-left,.controls-right,.page-control{display:flex;align-items:center;gap:7px}.controls button{border:1px solid #dbe3ed;background:#fff;border-radius:7px;height:35px;min-width:35px;color:#365675}.controls button:hover{background:#eff6fc}.page-control input{width:56px;padding:7px 4px;border:1px solid #cbd6e2;border-radius:6px;text-align:center}.page-control span{font-size:12px;color:#6e7e90}.controls #goBtn{font-size:12px;padding:0 10px}.controls .play-btn{font-size:12px;padding:0 12px;background:#f0f6fd;color:#1c639f}.tip{flex:none;margin:0;background:#fff;color:#8997a7;text-align:center;font-size:11px;padding:0 10px 12px}.turn-sheet{position:absolute;top:0;height:100%;width:50%;transform-style:preserve-3d;z-index:12;pointer-events:none}.turn-sheet.forward{right:0;transform-origin:left center}.turn-sheet.backward{left:0;transform-origin:right center}.turn-face{position:absolute;inset:0;backface-visibility:hidden;-webkit-backface-visibility:hidden;background:#fff;overflow:hidden}.turn-face.back{transform:rotateY(180deg)}.turn-face img{width:100%;height:100%;object-fit:fill}.scrim{display:none}@media(max-width:960px){.sidebar{width:256px}.sidebar-buttons{width:75px}.stage{padding-left:42px;padding-right:42px}.nav-arrow.prev{margin-left:-37px}.nav-arrow.next{margin-right:-37px}.header{padding:0 14px}}@media(max-width:700px){.app{min-height:0}.header{height:58px}.brand strong{font-size:14px}.brand-mark{height:34px;width:34px}.header-actions .topbtn span{display:none}.topbtn{padding:7px 10px}.mobile-menu{display:inline-flex!important}.sidebar{position:fixed;top:58px;bottom:0;left:0;z-index:30;width:min(325px,90vw);transform:translateX(-101%);transition:transform .2s}.sidebar.open{transform:translateX(0)}.scrim.show{display:block;position:fixed;inset:58px 0 0;background:#0007;z-index:29}.panel-title button{display:block}.viewer-top{padding:0 12px;height:43px}.stage{padding:10px 40px}.nav-arrow{width:28px;height:48px;font-size:30px}.nav-arrow.prev{margin-left:-34px}.nav-arrow.next{margin-right:-34px}.controls{height:58px;padding:0 8px}.controls-left,.controls-right,.page-control{gap:3px}.controls button{min-width:27px;height:32px}.controls .play-btn{font-size:0;min-width:32px;padding:0}.controls .play-btn:before{content:'▶';font-size:14px}.controls .play-btn.playing:before{content:'❚❚'}.page-control input{width:43px}.controls #goBtn{padding:0 6px}.tip{font-size:10px;padding-bottom:8px}.viewer-title{font-size:12px}}
.panel[hidden]{display:none!important}.mobile-menu{display:none;background:transparent;border:0;color:#fff;font-size:21px}

/* v2: always-collapsible hamburger drawer */
.mobile-menu{display:inline-flex!important;align-items:center;justify-content:center;width:38px;height:38px;flex:none;border:1px solid #56708e;border-radius:8px;background:#ffffff11;color:#fff;font-size:23px;line-height:1;cursor:pointer}
.layout{position:relative}
.sidebar{position:fixed;top:68px;bottom:0;left:0;z-index:31;width:min(360px,90vw);transform:translateX(-105%);transition:transform .24s cubic-bezier(.2,.8,.2,1);box-shadow:8px 0 22px #0001}
.sidebar.open{transform:translateX(0)}
.scrim.show{display:block;position:fixed;inset:68px 0 0;background:#101d3480;z-index:30}
.panel-title button{display:block;background:transparent;border:0;color:#344b63;font-size:20px;cursor:pointer}
.viewer{width:100%}
.stage{overflow:auto;display:flex;align-items:center;justify-content:center}
.book{filter:none!important;perspective:none!important;transform-style:flat!important;display:block!important;position:relative;flex:none;touch-action:pan-y}
.book:after{display:none!important}
.book .page{display:block;overflow:hidden;position:relative;width:100%;height:100%;background:#fff;cursor:grab}
.book .page img{width:100%;height:100%;display:block;object-fit:fill;pointer-events:none}
.book .page:active{cursor:grabbing}
/* StPageFlip supplies the actual flexible-page bend, dynamic highlights and shadows */
.book .stf__parent{margin:auto}
.book .stf__block{filter:drop-shadow(0 12px 16px #1f344a32)}
.book .page--hard{background:#fff}
.stage .nav-arrow{position:sticky}
@media(max-width:700px){.sidebar{top:58px;width:min(345px,94vw)}.scrim.show{inset:58px 0 0}.brand{gap:7px}.brand-mark{display:none}.book{touch-action:pan-y}}
/* Scroll room for zoomed spreads; layout remains compact at normal magnification */
.stage.is-zoomed{justify-content:safe center;align-items:safe center}
.fallback-book{width:min(65vh,90vw);height:min(83vh,100%);display:flex!important;align-items:center;justify-content:center;filter:drop-shadow(0 8px 12px #0002)!important}
.offline-warning{display:block;color:#a05322;font-size:11px;margin-left:12px}