:root{--bg:#f7f3eb;--panel:#fffcf6;--text:#272626;--muted:#716f6b;--line:#dfdad0;--accent:#9f643a;--soft:#f5e4a4;--word:#f6b945;--dim:#9a948b;--bar-shadow:0 4px 20px rgba(25,21,14,.07)}
*{box-sizing:border-box}html,body{height:100%;margin:0}body{background:var(--bg);color:var(--text);font:15px/1.5 system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;overflow:hidden;-webkit-text-size-adjust:100%}body[data-theme="dark"]{--bg:#171a1d;--panel:#202429;--text:#e6e8ec;--muted:#a6abb4;--line:#383d46;--dim:#999faa;--bar-shadow:0 4px 22px rgba(0,0,0,.2)}body[data-theme="sepia"]{--bg:#eddfc4;--panel:#f4e9d3;--text:#4b3427;--muted:#876f59;--line:#d8c4a9;--dim:#b5a18c}
button,input,select{font:inherit}button{cursor:pointer}button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #3c91d7;outline-offset:2px}button:disabled{opacity:.4;cursor:not-allowed}button,.primary-button,.secondary-button{touch-action:manipulation}.hidden,[hidden]{display:none!important}
#app{height:100dvh;display:flex;flex-direction:column;position:relative}.topbar{height:66px;min-height:66px;padding:0 max(14px,env(safe-area-inset-right)) 0 max(14px,env(safe-area-inset-left));display:flex;align-items:center;gap:12px;background:var(--panel);border-bottom:1px solid var(--line);z-index:4;transition:transform .3s ease}.icon-button{display:grid;place-items:center;border:0;background:transparent;color:var(--text);font-size:24px;border-radius:12px;min-width:42px;min-height:42px}.icon-button:hover,.text-button:hover{background:var(--line)}.book-heading{flex:1;min-width:0;display:flex;flex-direction:column;align-items:flex-start;border:0;background:transparent;text-align:left;color:var(--text);line-height:1.35;padding:7px 0}.book-heading b{font-size:14px;max-width:100%;white-space:nowrap;text-overflow:ellipsis;overflow:hidden}.book-heading small{font-size:12px;color:var(--muted)}.right-actions{display:flex;gap:2px}main{flex:1;min-height:0;position:relative;display:flex;overflow:hidden}.reader-section{flex:1;min-width:0;display:flex}.reader-viewport{width:100%;height:100%;overflow-y:auto;overscroll-behavior:contain;scrollbar-gutter:stable;-webkit-overflow-scrolling:touch}.reader-content{max-width:var(--read-width,700px);padding:42px 26px 48vh;margin:auto;font:var(--read-size,21px)/var(--read-line,1.8) Georgia,'Times New Roman',serif;letter-spacing:.005em;overflow-wrap:break-word;position:relative;color:var(--text);-webkit-user-select:text;user-select:text}.reader-content[data-font="sans"]{font-family:Arial,Helvetica,sans-serif}.reader-content[data-font="system"]{font-family:system-ui,-apple-system,sans-serif}.reader-content p{margin:.25em 0 0;text-align:left}.reader-content p+ p{margin-top:.06em}.reader-content .indent-para,.reader-content .indent-para1{text-indent:1.25em}.reader-content .parac,.reader-content .parac1{margin:1.15em 0;text-align:center;font-size:.86em}.reader-content h1,.reader-content h2,.reader-content h3{text-align:center;line-height:1.35;font-family:system-ui,sans-serif;font-size:1.2em;margin:1.6em 0 1.1em}.reader-content h4,.reader-content h5{font-size:1em}.reader-content blockquote{padding-left:1.2em;border-left:2px solid var(--line);font-style:italic}.reader-content .image,.reader-content figure{text-align:center;margin:1.2em auto}.reader-content img{max-width:100%;max-height:60vh;object-fit:contain;display:inline-block}.reader-content svg{max-width:100%}.reader-content a{color:inherit;text-decoration:none}.reader-content small{font-size:.72em}.reader-content hr{border:0;border-top:1px solid var(--line)}.reader-content.bionic-off .bionic-token{font-weight:inherit!important}.reader-content img[alt="Illustration"]{max-height:75px;opacity:.8}
.reader-content.dimmed{color:var(--dim)}.reader-content.dimmed h1,.reader-content.dimmed h2,.reader-content.dimmed h3{color:var(--dim)}
::highlight(sentence-highlight){background-color:var(--soft);color:var(--text)}::highlight(word-highlight){background-color:var(--word);color:var(--text)}
/* Range-rectangle fallback for browsers without the CSS Highlight API */.range-overlay{position:absolute;inset:0;z-index:0;pointer-events:none}.range-box{position:absolute;border-radius:3px;pointer-events:none}.range-box.sentence{background:var(--soft);opacity:.9}.range-box.word{background:var(--word)}.reader-content.range-fallback> :not(.range-overlay){position:relative;z-index:1}
.reader-content.reader-no-images img{display:none}.reader-content .epub-image-placeholder{font-size:.7em;color:var(--muted)}
.welcome{width:100%;display:grid;place-items:center;overflow:auto;padding:24px}.welcome-inner{max-width:480px;text-align:center;margin:auto}.welcome-mark{font-size:64px;color:var(--accent);line-height:1}.welcome h1{font-size:clamp(27px,5vw,42px);margin:12px 0}.welcome p{font-size:16px}.welcome .small{font-size:12px}.primary-button,.secondary-button{border:1px solid transparent;border-radius:12px;padding:11px 14px;min-height:44px;display:inline-flex;align-items:center;justify-content:center;text-align:center;font-weight:650;text-decoration:none}.primary-button{background:#9b5a31;color:#fff}.secondary-button{border-color:var(--line);background:var(--panel);color:var(--text)}.file-button input{display:none}.muted{color:var(--muted)}.small{font-size:12px!important}
.playbar{z-index:4;background:var(--panel);border-top:1px solid var(--line);padding:10px max(15px,env(safe-area-inset-right)) max(10px,env(safe-area-inset-bottom)) max(15px,env(safe-area-inset-left));box-shadow:var(--bar-shadow);transition:transform .3s ease}.progress-line{display:flex;gap:12px;align-items:center;max-width:920px;margin:auto}.progress-line input{flex:1;min-width:0}.progress-line span{min-width:36px;text-align:right;color:var(--muted);font-size:12px}.play-controls{display:flex;justify-content:center;align-items:center;gap:clamp(6px,3vw,22px);padding-top:5px}.play-button{min-height:54px;min-width:70px;border:0;border-radius:16px;background:#9b5a31;color:#fff;font-size:22px}.speed-button{min-width:44px;min-height:44px;border:1px solid var(--line);border-radius:12px;background:var(--bg);color:var(--text);font-size:24px}.text-button{border:0;color:var(--text);background:transparent;border-radius:7px;padding:7px 10px}.speed-line{display:flex;justify-content:space-between;gap:5px;max-width:700px;margin:auto;color:var(--muted);font-size:12px;align-items:center}.speed-line .text-button{font-size:12px;font-weight:650}.reader-active .topbar{transform:translateY(-100%)}.reader-active .playbar{transform:translateY(100%)}.reader-active main{margin-top:-66px;margin-bottom:-144px;z-index:3;pointer-events:none}.reader-active .reader-section{pointer-events:auto}.reader-active .topbar,.reader-active .playbar{pointer-events:auto}.reader-active .reader-content{padding-top:108px}
.scrim{position:absolute;inset:0;background:rgba(0,0,0,.4);z-index:6}.drawer{position:absolute;left:0;top:0;bottom:0;width:min(430px,95vw);z-index:7;background:var(--panel);box-shadow:0 10px 40px rgba(0,0,0,.18);display:flex;flex-direction:column}.settings-drawer{left:auto;right:0}.drawer-head{display:flex;justify-content:space-between;align-items:center;min-height:64px;padding:12px 18px;border-bottom:1px solid var(--line)}.drawer-head strong{font-size:19px}.drawer-tabs{display:flex;border-bottom:1px solid var(--line);gap:0;padding:0 6px}.drawer-tabs button{flex:1;min-width:0;padding:12px 4px;color:var(--muted);border:0;border-bottom:3px solid transparent;background:transparent;font-size:13px}.drawer-tabs button.active{color:var(--text);font-weight:700;border-color:var(--accent)}.drawer-body{padding:18px;overflow-y:auto;flex:1}.drawer-body h3{font-size:16px;margin:7px 0 14px}.drawer-item{width:100%;display:flex;justify-content:space-between;gap:8px;align-items:center;text-align:left;padding:14px 10px;border-radius:10px;background:transparent;border:0;border-bottom:1px solid var(--line);color:var(--text)}.drawer-item:hover,.drawer-item.selected{background:var(--bg)}.drawer-item small{color:var(--muted);display:block;font-size:11px}.drawer-item .line-title{font-weight:650}.drawer-item .trail{flex:none}.drawer-note{font-size:12px;color:var(--muted);padding:10px 0}.danger-button{border:0;background:none;color:#b34a42;text-decoration:underline;font-size:12px;padding:5px}.inline-import{display:flex;margin:10px 0}
.setting-group{border-bottom:1px solid var(--line);padding-bottom:20px;margin-bottom:20px}.setting-group h3{margin:0 0 14px}.setting-group label,.modal label{display:flex;flex-direction:column;font-size:13px;font-weight:600;gap:7px;margin-bottom:17px}.setting-group input[type="range"],.modal input{width:100%}.setting-group label output{font-variant-numeric:tabular-nums;float:right}.setting-group select,.modal input{padding:11px;border-radius:8px;border:1px solid var(--line);background:var(--bg);color:var(--text);font-size:15px}.setting-group .switch-row{flex-direction:row;justify-content:space-between;align-items:center}.setting-group input[type="checkbox"]{width:23px;height:23px}.colour-row{display:flex;gap:16px}.colour-row label{flex:1}.colour-row input{width:100%;height:40px;border:1px solid var(--line);background:transparent;border-radius:6px}.settings-drawer .drawer-body{padding-bottom:50px}
.modal-layer{position:absolute;inset:0;display:grid;place-items:center;z-index:12;background:rgba(0,0,0,.55);padding:16px}.modal{background:var(--panel);color:var(--text);max-width:520px;width:100%;max-height:92dvh;overflow:auto;border-radius:15px;padding:20px}.modal-head{display:flex;justify-content:space-between;align-items:center}.modal-head h2{font-size:20px;margin:0 0 12px}.modal-actions{display:flex;gap:10px;margin:10px 0}.modal-actions>*{flex:1}.modal pre{background:var(--bg);padding:13px;white-space:pre-wrap;overflow:auto;font-size:11px}.modal details{margin-top:16px;border-top:1px solid var(--line);padding-top:10px}.toast{position:absolute;bottom:170px;left:50%;z-index:20;transform:translateX(-50%);background:#34373b;color:#fff;border-radius:10px;padding:11px 16px;max-width:min(90%,460px);text-align:center;box-shadow:0 6px 30px #0004;opacity:0;pointer-events:none;transition:opacity .25s}.toast.visible{opacity:1}
.search-input{width:100%;border:1px solid var(--line);border-radius:8px;background:var(--bg);color:var(--text);padding:12px;font-size:16px}.search-result{display:block;width:100%;border:0;border-bottom:1px solid var(--line);background:none;color:var(--text);padding:12px 2px;text-align:left}.search-result small{color:var(--muted);display:block;margin-bottom:3px}.search-result span{font-size:13px}.search-result mark{background:var(--soft);color:#33291e}.cloud-status-ok{color:#267b4b}.cloud-status-bad{color:#ba4e41}
@media(max-width:640px){.topbar{height:56px;min-height:56px}.reader-content{padding:28px 19px 46vh;font-size:var(--read-size,20px);line-height:var(--read-line,1.8)}.playbar{padding-top:7px}.play-controls{gap:5px}.play-button{min-width:68px}.speed-line{font-size:11px}.reader-active main{margin-top:-56px;margin-bottom:-139px}.reader-active .reader-content{padding-top:93px}.reader-viewport{scrollbar-gutter:auto}.drawer{width:min(420px,100vw)}.toast{bottom:145px}}
@media(prefers-reduced-motion:reduce){.topbar,.playbar,.toast{transition:none}}

/* QuietReader v2: calm highlighting and reading modes */
body[data-theme="white"]{--bg:#ffffff;--panel:#fafafa;--text:#1c1d21;--muted:#646871;--line:#e2e5e9;--dim:#a0a5af}
body[data-theme="nightlight"]{--bg:#302419;--panel:#3a2b20;--text:#f2c991;--muted:#c39e76;--line:#654832;--dim:#977253;--bar-shadow:0 4px 20px #120a0555}
body[data-theme="midnight"]{--bg:#090b0d;--panel:#12151a;--text:#e6e9ed;--muted:#9b9ea7;--line:#292d33;--dim:#747a86}
/* Native highlight only paints words and sentence text colour; sentence background transitions separately */
::highlight(sentence-highlight){background-color:transparent;color:var(--text)}
::highlight(word-highlight){background-color:var(--word);color:#292011}
.reader-content.overlay-highlights> :not(.range-overlay){position:relative;z-index:1}
.reader-content .range-overlay{position:absolute;inset:0;z-index:0;pointer-events:none}
.sentence-layer,.word-layer{position:absolute;inset:0;pointer-events:none}
.sentence-layer{opacity:0;transition:opacity 175ms ease-out}
.sentence-layer.shown{opacity:1}
.range-box.sentence{border-radius:5px;background:var(--soft);opacity:.78}
.range-box.word{background:var(--word);border-radius:3px}
.reader-content.dimmed .range-box.sentence{opacity:.95}
.reader-viewport{position:relative}
.reader-viewport.paged-viewport{scrollbar-width:none}
.reader-viewport.paged-viewport::-webkit-scrollbar{display:none}
.page-turn-layer{position:absolute;inset:0;z-index:3;background:var(--bg);overflow:hidden;pointer-events:none;transform-origin:left center;backface-visibility:hidden;will-change:transform,opacity}
.page-turn-layer .reader-content{position:absolute;left:0;top:0;pointer-events:none;max-width:none}
.page-curl{box-shadow:inset -12px 0 30px #0002;transition:transform 420ms cubic-bezier(.25,.5,.2,1),opacity 400ms ease;transform:perspective(1200px) rotateY(0deg)}
.page-curl.departing{transform:perspective(1200px) rotateY(-80deg);opacity:0}
.page-fade{transition:opacity 200ms ease-out}
.page-fade.departing{opacity:0}
.speed-line select{background:var(--bg);border:1px solid var(--line);color:var(--text);border-radius:7px;font-size:12px;padding:5px;max-width:124px}
.library-tools{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin:10px 0 17px}
.library-tools select{width:100%;min-width:0;background:var(--bg);border:1px solid var(--line);border-radius:8px;color:var(--text);padding:10px 7px;font-size:12px}
.library-row{display:flex;gap:13px;padding:12px 0;border-bottom:1px solid var(--line);align-items:flex-start}
.library-cover{width:68px;height:98px;flex:none;object-fit:cover;border-radius:5px;background:#e0d6c7;box-shadow:0 2px 6px #0002}
.library-cover-placeholder{display:grid;place-items:center;background:#917358;color:#fff;font-weight:700;font-size:24px;letter-spacing:.03em}
.library-details{flex:1;min-width:0}
.library-details .drawer-item{padding:0 0 6px;border:0}
.library-details .line-title{font-size:14px;line-height:1.35}
.library-row-tools{display:flex;justify-content:space-between;gap:5px;align-items:center}
.category-button{border:1px solid var(--line);background:var(--bg);border-radius:100px;padding:5px 9px;font-size:11px;max-width:145px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;color:var(--text)}
.note-item{border-bottom:1px solid var(--line);padding:7px 0 14px}.note-item .drawer-item{border:0}.note-preview{margin:0 9px 8px;color:var(--text);font-size:13px;white-space:pre-wrap}.note-edit{padding:7px 12px;min-height:34px;font-size:12px}
.note-excerpt{font-family:Georgia,serif;font-size:14px;color:var(--muted);border-left:3px solid var(--soft);padding-left:12px;max-height:110px;overflow:auto}
.modal textarea{width:100%;min-height:130px;resize:vertical;font:inherit;line-height:1.5;padding:12px;border:1px solid var(--line);border-radius:9px;color:var(--text);background:var(--bg)}
@media(max-width:390px){.drawer-tabs button{font-size:11px}.speed-line select{max-width:99px;font-size:10px}.topbar{gap:5px}}
@media(prefers-reduced-motion:reduce){.sentence-layer,.page-curl,.page-fade{transition:none}}

.sentence-layer{z-index:1}.word-layer{z-index:2}

/* v2.1: visibly confirm the active interface version. */
.version-tag{font-size:10px;font-weight:700;color:var(--muted);background:var(--bg);border:1px solid var(--line);padding:2px 5px;border-radius:6px;white-space:nowrap;}
@media(max-width:390px){.version-tag{font-size:9px;padding:1px 3px}}