:root{--bg:#f6f5ef;--ink:#173d38;--muted:#667873;--line:#d7ddd4;--surface:#fff;--lime:#d7f373;--green:#193e38}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:95px}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.65 Arial,Helvetica,sans-serif}body.dark{--bg:#102923;--ink:#eaf2df;--muted:#a8bdb0;--line:#375248;--surface:#1a382f}a{color:inherit;text-decoration:none}button,input{font:inherit}button,a{touch-action:manipulation}button{cursor:pointer}header{max-width:1440px;margin:auto;height:94px;display:flex;align-items:center;justify-content:space-between;padding:0 5%;border-bottom:1px solid var(--line)}.brand{font-size:29px;font-weight:900;letter-spacing:-2px;display:flex;align-items:center;gap:15px}.brand span{letter-spacing:2px;font-size:10px;border-left:1px solid var(--line);padding-left:15px}nav{display:flex;gap:32px;font-size:13px}nav a:hover,.textlink:hover{text-decoration:underline}#theme{border:1px solid var(--line);border-radius:50%;width:37px;height:37px;background:transparent;color:var(--ink)}main{max-width:1440px;margin:auto}section{padding:76px 5%}.hero{display:grid;grid-template-columns:1.1fr 1fr;min-height:610px;align-items:center;padding-top:70px;padding-bottom:62px;overflow:hidden}.eyebrow{font-size:10px;font-weight:700;letter-spacing:2px;margin:0 0 22px}h1{font-size:clamp(44px,5.2vw,76px);line-height:1.09;letter-spacing:-4px;font-weight:500;margin:24px 0}h1 em{font-family:Georgia,serif;font-weight:400}h2{font-size:clamp(30px,3.5vw,44px);font-weight:500;line-height:1.15;letter-spacing:-1.8px;margin:0}h3{font-weight:500}.lead{color:var(--muted);max-width:430px;font-size:17px;line-height:1.8}.actions{display:flex;align-items:center;gap:24px;margin:28px 0}.button{display:inline-block;background:var(--green);color:#f4f7ea;border:0;border-radius:5px;padding:13px 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var(--line);border-radius:5px;background:transparent;color:var(--ink);padding:10px 15px;width:255px;font-size:12px}.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.card{padding:25px;text-align:left;border:1px solid var(--line);background:transparent;color:var(--ink);border-radius:7px;display:flex;flex-direction:column;min-height:243px;transition:transform .2s,background .2s}.card:hover{transform:translateY(-4px);background:var(--surface)}.card-top{display:flex;justify-content:space-between;font-size:10px;letter-spacing:1.2px;color:var(--muted)}.card h3{font-size:23px;line-height:1.25;letter-spacing:-.5px;margin:24px 0 12px}.card p{color:var(--muted);font-size:13px;line-height:1.6;margin:0 0 25px}.card-bottom{margin-top:auto;display:flex;justify-content:space-between;font-size:11px}.lab{background:#193e38;color:#f1f5e6;display:grid;grid-template-columns:1fr 1fr;gap:70px}.lab h2{font-size:40px}.lab p{font-size:14px;color:#baccc1;max-width:460px}.lab 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var(--line);padding:35px 5%;display:flex;align-items:center;justify-content:space-between;gap:30px;font-size:11px}footer p{color:var(--muted)}dialog{background:var(--bg);color:var(--ink);border:1px solid var(--line);border-radius:12px;max-width:700px;width:92%;max-height:85vh;padding:45px}dialog::backdrop{background:#071e17b8;backdrop-filter:blur(5px)}.close{float:right;font-size:28px;background:transparent;border:0;color:var(--ink)}dialog h2{font-size:32px;margin-bottom:22px}dialog h3{font-size:16px;margin-top:25px}.formula{background:var(--surface);padding:23px;border:1px solid var(--line);border-radius:7px;font:22px Georgia;text-align:center}dialog p{font-size:14px}dialog .eyebrow{margin-top:10px}.lesson-link{display:block;margin-top:25px;font-size:13px;text-decoration:underline}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #87a728;outline-offset:4px}@media(max-width:900px){nav{gap:16px}.hero{grid-template-columns:1fr 0.85fr}h1{letter-spacing:-2px}.cards{grid-template-columns:repeat(2,1fr)}.lab{gap:30px}.hero-meta{gap:15px}.actions{gap:15px}.section-head{align-items:start}.revision-grid{gap:10px}}@media(max-width:650px){header{height:75px}nav{display:none}.hero{display:flex;flex-direction:column;padding-top:45px}.hero-copy{width:100%}h1{font-size:49px}.atom{height:320px;width:100%;margin-top:20px}.hero-meta{justify-content:space-between}.ticker{gap:15px;font-size:8px;letter-spacing:1px;flex-wrap:wrap}.ticker i:last-of-type{display:none}.ticker span:last-child{display:none}section{padding:48px 5%}.section-head{display:block}.section-head>p{margin-top:20px!important}.controls{align-items:stretch;flex-direction:column}#search{width:100%}.cards{grid-template-columns:1fr}.card{min-height:220px}.lab,.revision-grid,.books{grid-template-columns:1fr}.wave-panel{min-height:230px}.lab h2{font-size:34px}.method{padding:25px 10px}.books h3{font-size:32px}footer{align-items:start;flex-direction:column;gap:15px}dialog{padding:28px}.flashcard{padding:25px}.flashcard .actions{flex-wrap:wrap}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
.library-toolbar{display:grid;grid-template-columns:1fr 1fr 1fr;gap:15px}label{font-size:12px}select,.library-toolbar input,.tool-box input{display:block;width:100%;padding:12px;background:var(--surface);color:var(--ink);border:1px solid var(--line);border-radius:5px;margin-top:6px;font:13px Arial}.reader-status{display:flex;justify-content:space-between;font-size:12px;border-block:1px solid var(--line);padding:12px 0;margin:20px 0}.reader-layout{display:grid;grid-template-columns:260px minmax(0,1fr);gap:25px}.reader-layout aside{max-height:1000px;overflow:auto;padding-right:10px}.small-actions{margin:10px 0;gap:8px;flex-wrap:wrap}.small-actions .outline{font-size:10px;padding:7px 10px}#matchCount{font-size:11px;color:var(--muted)}.page-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}.page-tile{border:1px solid var(--line);padding:5px;border-radius:5px;background:var(--surface);color:var(--ink);text-align:left;font-size:10px}.page-tile img{width:100%;aspect-ratio:0.707;object-fit:contain;background:white;display:block}.page-tile.active{border:2px solid #769b24}.page-tile span{display:block;padding:5px}.reader-controls,.zoom-controls{display:flex;align-items:center;gap:7px;flex-wrap:wrap;margin-bottom:12px}.reader-controls .outline,.zoom-controls .outline{font-size:11px;padding:6px 11px}.reader-controls input{width:64px;background:var(--surface);color:var(--ink);border:1px solid var(--line);padding:7px;border-radius:4px}.zoom-controls output{font-size:12px;min-width:40px}#pageTotal{font-size:12px}.image-viewport{overflow:auto;max-height:880px;background:#d8ddd4;border:1px solid var(--line);border-radius:5px;overscroll-behavior:contain}.image-viewport img{display:block;width:100%;max-width:none;height:auto;margin:auto}.reader-main:fullscreen{overflow:auto;background:var(--bg);padding:20px}.reader-main:fullscreen .image-viewport{max-height:85vh}.note-label{display:flex;justify-content:space-between;gap:15px;margin-top:20px}.note-label span{color:var(--muted);font-size:10px}#pageNotes{width:100%;border:1px solid var(--line);border-radius:5px;padding:15px;background:var(--surface);color:var(--ink);margin-top:8px;font:14px/1.6 Arial;resize:vertical}.outline.selected{background:var(--lime);color:#193e38}.tools-grid{display:grid;grid-template-columns:1fr 1fr;gap:25px}.tool-box{border:1px solid var(--line);border-radius:8px;background:var(--surface);padding:30px}.tool-box h3{font-size:26px;margin:0 0 20px}.tool-box label{display:block;margin-bottom:15px}.calc-result{padding:20px;background:var(--bg);font-size:14px;line-height:1.9;margin-top:20px;border-radius:5px;white-space:pre-line}.quiz-option{display:block;width:100%;text-align:left;background:var(--bg);color:var(--ink);border:1px solid var(--line);border-radius:5px;padding:12px;margin:8px 0;font-size:13px}.quiz-option.correct{border-color:#6b9830;background:#d7f373;color:#173d38}.quiz-option.wrong{border-color:#b85447}#quizFeedback,#quizScore{font-size:13px}#quizNext:disabled{opacity:.4;cursor:default}@media(max-width:900px){.reader-layout{grid-template-columns:190px minmax(0,1fr)}.library-toolbar{grid-template-columns:1fr 1fr}.library-toolbar label:last-child{grid-column:1/-1}}@media(max-width:650px){.library-toolbar,.tools-grid,.reader-layout{grid-template-columns:1fr}.reader-layout aside{max-height:250px;order:2}.page-grid{grid-template-columns:repeat(4,1fr)}.reader-main{order:1}.image-viewport{max-height:650px}.tool-box{padding:22px}.reader-status{gap:15px;flex-wrap:wrap}nav{display:none}}
/* Fluid sizing from compact phones to ultrawide displays. */
html{min-width:0;scroll-padding-top:clamp(70px,7vw,110px)}body{overflow-wrap:break-word}img,svg{max-width:100%}button,input,select,textarea{max-width:100%}main,header{max-width:1920px;width:100%}main>*{min-width:0}header{position:relative;padding-inline:clamp(12px,4vw,90px);gap:16px}section{padding-inline:clamp(12px,4vw,90px);padding-block:clamp(38px,5.4vw,100px)}.hero{gap:clamp(18px,3vw,65px)}.hero-copy,.atom,.lab>div,.reader-main,.reader-layout aside,.tool-box,.flashcard,.method,.section-head>div{min-width:0}.header-actions{display:flex;gap:8px;align-items:center;flex-shrink:0}.icon-button{width:40px;height:40px;border:1px solid var(--line);border-radius:50%;background:transparent;color:var(--ink);font-size:22px;display:inline-grid;place-items:center}.header-actions #theme{width:40px;height:40px}.header-actions button{flex-shrink:0}#menuToggle{display:none}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}#exitFocus{position:fixed;bottom:max(14px,env(safe-area-inset-bottom));right:max(14px,env(safe-area-inset-right));z-index:50;box-shadow:0 4px 24px #0004}#exitFocus[hidden]{display:none}.focus-mode main,.focus-mode header{max-width:none}.focus-mode .image-viewport{max-height:85dvh}html:fullscreen{overflow-y:auto;background:var(--bg)}.cards{grid-template-columns:repeat(3,minmax(0,1fr))}.books,.tools-grid,.revision-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.library-toolbar{grid-template-columns:repeat(3,minmax(0,1fr))}.reader-layout{grid-template-columns:clamp(190px,20vw,310px) minmax(0,1fr)}.image-viewport{max-height:min(1000px,78dvh)}.reader-layout aside{max-height:min(1200px,105dvh)}.reader-controls,.zoom-controls{row-gap:10px}.reader-controls label{display:flex;align-items:center;gap:6px}.zoom-controls a{white-space:normal}.reader-controls button,.zoom-controls button,.filters button{min-height:40px}.note-label{flex-wrap:wrap}.readouts{flex-wrap:wrap;gap:20px 35px}.readouts>div{min-width:0}.books h3{overflow-wrap:anywhere}.links a{overflow-wrap:anywhere}.formula{overflow-x:auto}.atom .orbit{max-width:100%}footer{padding-inline:clamp(12px,4vw,90px);flex-wrap:wrap}.hero .actions{flex-wrap:wrap}.lab{grid-template-columns:minmax(0,1fr) minmax(0,1fr)}nav{gap:clamp(12px,2vw,32px)}.tool-box select{white-space:normal}select,input[type=search]{min-width:0}
@media(min-width:1600px){body{font-size:18px}.hero{min-height:730px}.hero h1{font-size:clamp(76px,5.2vw,96px)}.atom{height:540px}.hero .lead{max-width:560px;font-size:20px}.card{min-height:280px;padding:32px}.card h3{font-size:28px}.card p{font-size:15px}.cards{gap:24px}.reader-main{font-size:18px}.image-viewport{max-height:1000px}.page-grid{gap:14px}nav{font-size:15px}}
@media(max-width:1100px){.brand span{letter-spacing:1px;padding-left:10px}.brand{gap:10px}nav{font-size:12px;gap:14px}.header-actions{gap:6px}.lab{gap:28px}.library-toolbar{grid-template-columns:repeat(2,minmax(0,1fr))}.library-toolbar label:last-child{grid-column:1/-1}.hero h1{font-size:clamp(42px,5.5vw,64px)}}
@media(max-width:850px){header{height:78px}#menuToggle{display:inline-grid}nav{display:none;position:absolute;top:100%;left:0;right:0;z-index:20;padding:16px;background:var(--bg);border-bottom:1px solid var(--line);box-shadow:0 15px 25px #0001}nav.open{display:flex;flex-wrap:wrap;gap:8px}nav a{padding:12px 16px;flex:1 1 130px;font-size:14px}.cards{grid-template-columns:repeat(2,minmax(0,1fr))}.hero{grid-template-columns:minmax(0,1fr) minmax(0,.8fr)}.hero-meta{flex-wrap:wrap}.reader-layout{grid-template-columns:170px minmax(0,1fr)}.reader-controls .outline,.zoom-controls .outline{padding:8px 10px}.section-head{align-items:start}.reader-layout aside{padding-right:0}.lab h2{font-size:34px}}
@media(max-width:650px){.hero{display:flex;align-items:stretch}.hero h1{font-size:clamp(34px,8.5vw,53px);letter-spacing:-1.5px}.hero-copy{width:auto}.hero .lead{font-size:16px}.hero-meta{gap:10px;justify-content:flex-start}.hero-meta span{flex:1 1 85px}.atom{height:clamp(230px,70vw,370px);width:100%}.cards,.books,.tools-grid,.revision-grid,.lab,.library-toolbar,.reader-layout{grid-template-columns:minmax(0,1fr)}.library-toolbar label:last-child{grid-column:auto}.reader-layout aside{order:2;max-height:300px}.reader-main{order:1}.page-grid{grid-template-columns:repeat(4,minmax(0,1fr))}.reader-layout{gap:14px}.image-viewport{max-height:75dvh}.reader-status{font-size:11px}.section-head{display:block}.section-head>p{margin-top:16px!important}.controls{flex-direction:column;align-items:stretch}.controls input{width:100%!important}.wave-panel{min-height:200px}.lab{gap:25px}.flashcard .actions{flex-wrap:wrap}.actions{gap:12px}.ticker{justify-content:space-around}.ticker span{font-size:8px;letter-spacing:.7px}.ticker span:last-child,.ticker i:last-of-type{display:none}.ticker i{font-size:15px}.tool-box input,.tool-box select,.library-toolbar input,.library-toolbar select,#pageNotes,#search{font-size:16px}.books h3{font-size:clamp(26px,6.8vw,38px)}footer{align-items:flex-start}.reader-main:fullscreen{padding:10px}dialog{padding:22px;max-height:90dvh}dialog h2{font-size:28px}}
@media(max-width:360px){header{gap:8px;padding-inline:10px}.brand{font-size:25px;gap:8px}.brand span{font-size:8px;letter-spacing:.7px;max-width:62px;padding-left:8px}.header-actions{gap:4px}.icon-button,.header-actions #theme{width:34px;height:34px;font-size:19px}.hero h1{font-size:clamp(28px,10vw,36px)}.hero-meta b{font-size:20px}.eyebrow{letter-spacing:1px;font-size:9px}.hero-meta span{flex-basis:75px}.ticker{padding-inline:10px;gap:6px}.ticker i{display:none}.page-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.filters{gap:5px}.filters button{padding:8px 12px}.flashcard,.card,.tool-box,.books a{padding:19px}.readouts b{font-size:23px}.reader-controls,.zoom-controls{gap:5px}.reader-controls .outline,.zoom-controls .outline{font-size:10px;padding:7px 9px}.section-head h2{font-size:29px}.hero .actions{align-items:flex-start;flex-direction:column}.source-note{font-size:11px}}
@media(max-height:500px) and (orientation:landscape){header{height:65px}.hero{min-height:0}.atom{height:260px}.image-viewport{max-height:70dvh}.reader-main:fullscreen .image-viewport{max-height:65dvh}dialog{max-height:94dvh}}
@supports(padding:env(safe-area-inset-left)){header,footer{padding-left:max(12px,4vw,env(safe-area-inset-left));padding-right:max(12px,4vw,env(safe-area-inset-right))}}
.spark-scene{position:relative;min-width:0;min-height:470px;display:grid;place-items:center;isolation:isolate}.spark-halo{position:absolute;width:85%;aspect-ratio:1;border-radius:50%;background:radial-gradient(circle,#d7f37360 0%,#bcdac033 50%,transparent 72%);z-index:-1}.spark-mascot{width:min(100%,450px);height:auto;filter:drop-shadow(0 18px 25px #163d3815);animation:spark-bob 5s ease-in-out infinite}.spark-bubble{position:absolute;top:6%;right:0;max-width:190px;background:var(--surface);border:1px solid var(--line);border-radius:22px 22px 22px 3px;padding:16px 20px;font:italic 19px/1.35 Georgia;color:var(--ink);transform:rotate(5deg);box-shadow:0 8px 30px #173d3809}.scene-symbol{position:absolute;font:italic 54px Georgia;color:var(--ink);opacity:.45;animation:symbol-drift 7s ease-in-out infinite}.sym-one{left:7%;top:16%;transform:rotate(-15deg)}.sym-two{right:2%;top:58%;animation-delay:-2s}.sym-three{left:9%;bottom:16%;font-size:36px;animation-delay:-4s}.spark-caption{font-size:9px;letter-spacing:2px;position:absolute;bottom:0;color:var(--muted);text-align:center}.world-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.world-card{border:1px solid var(--line);border-radius:15px;overflow:hidden;background:var(--surface);transition:transform .25s,box-shadow .25s}.world-card:hover{transform:translateY(-7px);box-shadow:0 18px 35px #173d3812}.world-card>div:last-child{padding:26px}.world-card .eyebrow{font-size:9px}.world-card h3{font-size:29px;line-height:1.2;margin:15px 0 10px;letter-spacing:-.8px}.world-card p{font-size:13px;color:var(--muted)}.world-card b{font-size:12px}.world-art{position:relative;overflow:hidden}.world-art img{display:block;width:100%;height:auto;transition:transform .6s}.world-card:hover .world-art img{transform:scale(1.05)}.world-float{position:absolute;right:10%;top:15%;display:grid;place-items:center;width:40px;height:40px;border:1px solid #193e3833;border-radius:50%;background:#ffffff70;color:#193e38;font:24px Georgia;animation:symbol-drift 6s ease-in-out infinite}.world-card:nth-child(2) .world-float{animation-delay:-2s}.world-card:nth-child(3) .world-float{animation-delay:-4s}.reveal-ready{opacity:0;transform:translateY(18px);transition:opacity .6s,transform .6s}.reveal-ready.in-view{opacity:1;transform:translateY(0)}.world-card:nth-child(2){transition-delay:.06s}.world-card:nth-child(3){transition-delay:.12s}#visual-worlds{border-bottom:1px solid var(--line)}@keyframes spark-bob{0%,100%{transform:translateY(0) rotate(-1deg)}50%{transform:translateY(-12px) rotate(1deg)}}@keyframes symbol-drift{0%,100%{translate:0 0;rotate:-7deg}50%{translate:0 -12px;rotate:7deg}}.motion-paused *{animation-play-state:paused!important}.motion-paused .reveal-ready{opacity:1;transform:none}.motion-paused *{scroll-behavior:auto!important;transition-duration:0s!important}@media(min-width:1600px){.spark-scene{min-height:580px}.spark-mascot{width:530px}.spark-bubble{font-size:23px;max-width:230px}}@media(max-width:850px){.world-grid{gap:15px}.world-card>div:last-child{padding:20px}.world-card h3{font-size:24px}.spark-scene{min-height:380px}.spark-bubble{font-size:16px;padding:12px;max-width:160px}}@media(max-width:650px){.world-grid{grid-template-columns:1fr}.world-art img{max-height:260px;object-fit:cover}.world-card>div:last-child{padding:24px}.spark-scene{min-height:370px;margin-top:10px}.spark-mascot{width:min(95%,360px)}.spark-bubble{right:0;top:0;font-size:17px}.spark-caption{font-size:8px}#visual-worlds .section-head{display:flex;flex-wrap:wrap;align-items:center;gap:20px}.world-float{right:8%}.scene-symbol{font-size:40px}}@media(max-width:360px){.spark-scene{min-height:300px}.spark-bubble{font-size:14px;max-width:145px}.spark-caption{letter-spacing:1px}.world-card h3{font-size:26px}}@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}.reveal-ready{opacity:1;transform:none}html{scroll-behavior:auto}}
.math5-banner{margin:0 clamp(12px,4vw,90px);padding:28px 32px;display:flex;align-items:center;justify-content:space-between;gap:25px;background:#e8dff5;color:#59416d;border:1px solid #cbb8df;border-radius:14px}.math5-banner h2{font-size:30px}.math5-banner p:not(.eyebrow){font-size:13px;margin-bottom:0}.math5-banner .eyebrow{margin-bottom:12px}.math5-banner .button{flex-shrink:0}.books .drive-math5{background:#e8dff5;color:#59416d}.external-source-note{display:block;margin-top:18px;font-size:11px;line-height:1.6;max-width:350px}@media(max-width:650px){.math5-banner{flex-direction:column;align-items:flex-start;padding:24px}.math5-banner h2{font-size:27px}}
.reader-layout[hidden],.drive-reader[hidden]{display:none!important}.drive-reader{border:1px solid var(--line);border-radius:9px;padding:24px;background:var(--surface)}.drive-reader-heading{display:flex;align-items:center;gap:25px;justify-content:space-between}.drive-reader-heading h3{margin:0;font-size:28px}.drive-reader-heading p{font-size:13px;color:var(--muted);max-width:650px}.drive-reader-heading .button{flex-shrink:0}.drive-reader iframe{display:block;width:100%;height:clamp(400px,78dvh,1100px);border:1px solid var(--line);border-radius:6px;background:#f0f0f0}select:disabled,input:disabled{opacity:.55}@media(max-width:650px){.drive-reader{padding:15px}.drive-reader-heading{align-items:flex-start;flex-direction:column;gap:10px}.drive-reader iframe{height:70dvh;min-height:350px}.drive-reader-heading h3{font-size:24px}}
.math5-banner-art{width:clamp(150px,22vw,280px);height:auto;flex-shrink:0;border-radius:10px;object-fit:contain}.math5-banner>div{flex:1;min-width:0}@media(max-width:900px){.math5-banner{flex-wrap:wrap}.math5-banner-art{width:180px}}@media(max-width:650px){.math5-banner-art{width:100%;max-width:420px;align-self:center}.math5-banner>div{width:100%}}
/* Keep the topic ribbon and new-book feature visually separate. */
.ticker{display:flex;flex-wrap:wrap;justify-content:center;gap:14px clamp(18px,3vw,48px);line-height:1.7;padding-block:22px}.ticker span{display:inline-block;white-space:nowrap}.ticker i{flex:0 0 auto}.math5-banner{margin-block:clamp(28px,3vw,48px);clear:both}#visual-worlds{padding-top:clamp(32px,4vw,60px)}@media(max-width:650px){.ticker{gap:12px 24px;padding:20px 16px}.ticker span{font-size:10px;letter-spacing:1px}.ticker i{display:none}.math5-banner{margin-block:28px;gap:22px}}@media(max-width:360px){.ticker{gap:12px 20px}.ticker span{font-size:9px}.math5-banner{margin-block:24px}}
/* Dedicated PDF fullscreen keeps navigation visible and maximizes the document. */
.reader-main:fullscreen,.reader-main:-webkit-full-screen,.reader-main.pdf-expanded,.drive-reader:fullscreen,.drive-reader:-webkit-full-screen,.drive-reader.pdf-expanded{box-sizing:border-box;display:flex!important;flex-direction:column;width:100%;height:100dvh;max-width:none;max-height:none;background:var(--bg);color:var(--ink);padding:12px;gap:8px;border:0;border-radius:0;overflow:hidden}.reader-main.pdf-expanded,.drive-reader.pdf-expanded{position:fixed;inset:0;z-index:1000}.pdf-overlay-open{overflow:hidden}.reader-main:fullscreen .image-viewport,.reader-main.pdf-expanded .image-viewport{flex:1;min-height:0;max-height:none;width:100%;overflow:auto}.reader-main:fullscreen .reader-controls,.reader-main.pdf-expanded .reader-controls,.reader-main:fullscreen .zoom-controls,.reader-main.pdf-expanded .zoom-controls{flex-shrink:0;margin:0}.reader-main:fullscreen #pageCaption,.reader-main.pdf-expanded #pageCaption,.reader-main:fullscreen .note-label,.reader-main.pdf-expanded .note-label,.reader-main:fullscreen #pageNotes,.reader-main.pdf-expanded #pageNotes,.reader-main:fullscreen>.actions,.reader-main.pdf-expanded>.actions{display:none}.drive-reader:fullscreen iframe,.drive-reader.pdf-expanded iframe{flex:1;min-height:0;height:auto;width:100%;border:0}.drive-reader:fullscreen .drive-reader-heading,.drive-reader.pdf-expanded .drive-reader-heading{flex-direction:row;flex-wrap:wrap;flex-shrink:0;justify-content:flex-start;gap:12px}.drive-reader:fullscreen .drive-reader-heading h3,.drive-reader.pdf-expanded .drive-reader-heading h3{font-size:20px}.drive-reader:fullscreen .drive-reader-heading p,.drive-reader.pdf-expanded .drive-reader-heading p,.drive-reader:fullscreen>.source-note,.drive-reader.pdf-expanded>.source-note{display:none}#fullDriveReader{white-space:nowrap;flex-shrink:0;min-height:42px}#fullReader{min-height:42px}.drive-reader-heading{flex-wrap:wrap}@media(max-width:650px){.reader-main:fullscreen,.reader-main.pdf-expanded,.drive-reader:fullscreen,.drive-reader.pdf-expanded{padding:8px;gap:6px}.drive-reader:fullscreen .drive-reader-heading h3,.drive-reader.pdf-expanded .drive-reader-heading h3{font-size:16px}.drive-reader:fullscreen .drive-reader-heading .button,.drive-reader.pdf-expanded .drive-reader-heading .button{padding:8px 12px;font-size:11px}.reader-main:fullscreen .reader-controls .outline,.reader-main.pdf-expanded .reader-controls .outline{min-height:34px}.reader-main:fullscreen .zoom-controls .outline,.reader-main.pdf-expanded .zoom-controls .outline{min-height:34px}}