@font-face{font-family:Bopo;src:url('assets/bopo-Regular.otf') format('opentype');font-weight:400;font-display:swap}
:root{--paper:#f8f7f3;--ink:#252622;--muted:#73756d;--line:#d9dbd1;--accent:#ba492e;--panel:#edeee5}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:90px}body{margin:0;background:var(--paper);color:var(--ink);font-family:"Helvetica Neue","PingFang SC","Microsoft YaHei",sans-serif;font-size:14px;-webkit-font-smoothing:antialiased}button,input,textarea,select{font:inherit;color:inherit}button,a,input,textarea,select{-webkit-tap-highlight-color:transparent}button,a{touch-action:manipulation}a{color:inherit;text-decoration:none}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:2px solid var(--accent);outline-offset:5px}button{border:0;background:none}header{height:88px;padding:0 4.2%;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.logo{font-family:Bopo,sans-serif;font-size:32px;display:flex;align-items:center;gap:17px}.logo span{font:12px "PingFang SC",sans-serif;border-left:1px solid #c6c8c0;padding-left:17px;letter-spacing:2px}nav{display:flex;align-items:center;gap:34px}nav a{font-size:13px}nav a span{margin-left:14px}.download{display:inline-flex;background:var(--ink);color:var(--paper);padding:14px 21px;align-items:center;justify-content:space-between;gap:30px;border:1px solid var(--ink);transition:background .2s}.download:hover{background:var(--accent);border-color:var(--accent)}main{max-width:1800px;margin:auto}.hero{padding:30px 4.2% 0}.eyebrow,.measure,.card-label,.board-caption,.index,.small-stamp,.glyph-meta,.glyph-note{font-size:10px;letter-spacing:1.3px}.eyebrow{display:flex;justify-content:space-between;color:var(--muted)}.eyebrow i{display:inline-block;width:6px;height:6px;border-radius:50%;background:var(--accent);margin-right:9px}.wordmark{position:relative;margin-top:42px;border-left:1px solid var(--line);border-right:1px solid var(--line);background:linear-gradient(to bottom,transparent calc(100% - 1px),var(--line) 0) 0 0/100% 25%;}.giant{font-family:Bopo,sans-serif;font-size:clamp(160px,30.9vw,530px);line-height:1.04;letter-spacing:-.065em;text-align:center;padding:0 4% 1%;font-weight:400;white-space:nowrap}.giant span{color:var(--accent)}.measure{display:flex;justify-content:space-between;color:#878a7d;position:absolute;width:100%;padding:0 8px}.measure.top{top:-17px}.measure.bottom{bottom:-20px}.hero-bottom{display:grid;grid-template-columns:1.25fr 1fr auto;align-items:start;margin:64px 0 44px;gap:24px}h1{font-size:clamp(23px,2.5vw,39px);font-weight:500;letter-spacing:-1px;margin:0}p{line-height:1.9}.hero-bottom p{margin:0 0 17px;color:#64675d;font-size:13px}.text-link{font-size:12px;display:inline-flex;gap:40px;border-bottom:1px solid #9c9f94;padding-bottom:7px}.small-stamp{border:1px solid var(--line);padding:12px 15px;line-height:1.9;color:var(--muted);transform:rotate(-5deg)}.specimen-board{display:grid;grid-template-columns:1fr .95fr 1.2fr;gap:15px}.specimen{padding:18px 22px;min-height:255px;border:1px solid var(--line);overflow:hidden}.card-label{display:flex;justify-content:space-between}.vowel{background:#eceee5}.tones{background:#f0eee7}.phrase{background:#e8ebe1}.bopo{font-family:Bopo,sans-serif;font-weight:400}.letter-lines{margin:14px -22px 8px;display:flex;justify-content:center;gap:24px;background:repeating-linear-gradient(to bottom,transparent 0,transparent 34px,#ccd1c2 35px,transparent 36px);height:145px;align-items:center}.letter-lines span{font-size:130px;line-height:1}.card-note{font-size:10px;color:#77796f;letter-spacing:1px;margin-top:10px}.tone-row{font-size:62px;line-height:1.23;padding:15px 0 5px;letter-spacing:2px}.phrase-text{font-size:56px;line-height:1.2;padding:20px 0 8px}.phrase-translation{font-size:15px;color:#65695d;letter-spacing:3px}.board-caption{display:flex;justify-content:space-between;margin:16px 0 0;color:#86897f}.section{padding:105px 4.2% 0}.section-heading{display:flex;justify-content:space-between;align-items:end;margin-bottom:32px;gap:30px}.index{color:var(--accent);font-size:10px}h2{font-size:30px;font-weight:500;letter-spacing:-.7px;margin:16px 0 0;line-height:1.5}.section-heading p{color:var(--muted);font-size:12px;margin:0}.tester{border:1px solid var(--line)}.toolbar{display:flex;align-items:center;gap:24px;padding:18px 22px;border-bottom:1px solid var(--line);font-size:11px}.toolbar label:first-child{margin-right:auto;color:var(--muted)}.toolbar label span{margin-left:17px;color:var(--ink)}.size-control{display:flex;align-items:center;gap:14px}.size-control input{accent-color:var(--ink);width:100px}.size-control output{min-width:36px}#guides span{color:var(--accent);margin-left:5px}#sample{width:100%;border:0;resize:vertical;background-color:transparent;font-size:72px;line-height:1.65;min-height:300px;padding:28px 30px;display:block;border-radius:0}#sample.lined{background-image:repeating-linear-gradient(to bottom,transparent 0,transparent calc(1.65em - 1px),#e1e3d9 calc(1.65em - 1px),#e1e3d9 1.65em);background-position:0 28px}.tester-bottom{padding:15px 22px;border-top:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;gap:15px;font-size:10px;color:var(--muted)}.presets{display:flex;gap:8px}.presets button{padding:8px 12px;border:1px solid transparent}.presets button.active{border-color:var(--line);background:#ebece4;color:var(--ink)}.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:30px}.feature-grid article+article{border-left:1px solid var(--line);padding-left:30px}.feature-demo{height:175px;display:flex;align-items:center;font-size:clamp(32px,4vw,65px);letter-spacing:normal;white-space:nowrap}.feature-demo>span{color:var(--accent);margin-left:10px}.combined{flex-direction:column;justify-content:center;align-items:flex-start;gap:10px}.combined span:first-child{font-size:40px;color:var(--ink);margin:0}.combined span:last-child{font-size:30px;margin:0;letter-spacing:8px}h3{font-size:17px;font-weight:500}.feature-grid p{font-size:12px;color:var(--muted);max-width:300px}.glyph-browser{display:grid;grid-template-columns:1fr 2fr;border:1px solid var(--line)}.glyph-preview{background:var(--panel);padding:24px;display:flex;flex-direction:column;justify-content:space-between;border-right:1px solid var(--line)}#selected-glyph{font-size:180px;text-align:center;line-height:1.4;color:var(--accent)}.glyph-meta{display:flex;align-items:center;justify-content:space-between}.glyph-meta button{font-size:11px}.glyph-list{padding:24px}.glyph-tabs{display:flex;gap:22px;margin-bottom:24px}.glyph-tabs button{font-size:12px;padding:0 0 10px;border-bottom:2px solid transparent}.glyph-tabs button.active{border-color:var(--accent);color:var(--accent)}#glyph-grid{display:grid;grid-template-columns:repeat(8,1fr);border-top:1px solid var(--line);border-left:1px solid var(--line)}#glyph-grid button{font-family:Bopo,sans-serif;font-size:29px;padding:14px 4px;border-right:1px solid var(--line);border-bottom:1px solid var(--line)}#glyph-grid button:hover,#glyph-grid button.active{background:var(--panel);color:var(--accent)}.glyph-note{color:var(--muted);margin:18px 0 0}.download-section{margin-top:105px;padding:64px 4.2%;display:flex;justify-content:space-between;align-items:center;background:#e9ebe1}.download-section h2{font-size:44px}.download-info{min-width:330px}.download-info p{font-size:13px}.large{width:100%;padding:20px}.download-info>span{display:block;font-size:10px;color:var(--muted);margin-top:14px}.feedback{display:grid;grid-template-columns:1fr 1fr;gap:60px;padding-bottom:90px}.feedback>div>p{color:var(--muted);font-size:12px;margin-top:22px}form{display:flex;flex-direction:column;gap:10px}form label{font-size:12px;margin-top:8px}form label span{color:var(--muted)}form input,form select,form textarea{padding:13px;border:1px solid var(--line);background:transparent;border-radius:0;font-size:13px;width:100%}form textarea{min-height:115px;resize:vertical}.form-bottom{display:flex;gap:18px;align-items:center;justify-content:space-between;margin-top:6px}.form-bottom p{font-size:10px;color:var(--muted)}.form-bottom button{font-size:12px;white-space:nowrap}#feedback-status{font-size:12px;color:var(--accent);margin:0}footer{margin:0 4.2%;border-top:1px solid var(--line);padding:28px 0;display:flex;gap:30px;align-items:center;font-size:10px;color:var(--muted)}footer span:nth-child(3){margin-left:auto}footer .logo{color:var(--ink);font-size:25px}::selection{background:#e1c2a9}
@media(min-width:1600px){.giant{font-size:490px}}@media(max-width:900px){.hero-bottom{grid-template-columns:1fr 1fr}.small-stamp{display:none}.specimen{padding:16px;min-height:220px}.tone-row{font-size:48px}.phrase-text{font-size:45px}.letter-lines span{font-size:110px}.letter-lines{height:120px}.toolbar{flex-wrap:wrap;gap:15px}.feature-grid{gap:18px}.feature-grid article+article{padding-left:18px}.feature-demo{font-size:32px}.feedback{gap:30px}.form-bottom{align-items:start;flex-direction:column}}
@media(max-width:600px){header{height:72px;padding:0 5%}.logo{font-size:27px;gap:10px}.logo span{display:none}nav{gap:20px}nav a{font-size:11px}nav a span{margin-left:4px}.download{padding:11px 14px}.hero{padding:25px 5% 0}.eyebrow{font-size:8px;letter-spacing:.4px}.eyebrow>span:last-child{display:none}.wordmark{margin-top:42px}.giant{font-size:30vw;line-height:1.2}.measure{font-size:8px}.hero-bottom{margin:46px 0 30px;grid-template-columns:1fr;gap:18px}h1{font-size:27px}.hero-bottom p{font-size:12px}.specimen-board{grid-template-columns:1fr 1fr;gap:10px}.specimen{min-height:210px;padding:14px}.card-label{font-size:8px}.phrase{grid-column:1/-1;min-height:180px;position:relative}.phrase-text{font-size:51px;line-height:1.1}.phrase-translation{position:absolute;right:20px;bottom:24px;font-size:13px}.tone-row{font-size:45px;padding-top:24px}.letter-lines{gap:12px}.letter-lines span{font-size:96px}.card-note{font-size:8px}.board-caption{font-size:8px;letter-spacing:.3px}.section{padding:65px 5% 0}.section-heading{display:block;margin-bottom:24px}.section-heading p{margin-top:15px;font-size:11px}h2{font-size:25px}.toolbar{padding:14px;gap:17px;font-size:10px}.toolbar label:first-child{width:100%}.size-control{gap:8px}.size-control input{width:80px}#sample{font-size:38px;min-height:240px;padding:22px 15px;line-height:1.65}#sample.lined{background-position:0 22px}.tester-bottom{padding:12px;flex-direction:column;align-items:start}.presets button{font-size:10px;padding:7px 10px}.feature-grid{grid-template-columns:1fr;gap:18px}.feature-grid article+article{border-left:0;border-top:1px solid var(--line);padding:0}.feature-demo{height:130px;font-size:52px}.feature-grid p{max-width:none}.glyph-browser{grid-template-columns:1fr}.glyph-preview{border-right:0;border-bottom:1px solid var(--line);padding:20px}#selected-glyph{font-size:130px;line-height:1.3}.glyph-list{padding:18px}#glyph-grid{grid-template-columns:repeat(6,1fr)}#glyph-grid button{padding:12px 4px;font-size:26px}.download-section{margin-top:65px;padding:40px 5%;display:block}.download-section h2{font-size:33px}.download-info{margin-top:30px;min-width:0}.large{padding:18px}.feedback{grid-template-columns:1fr;gap:20px;padding-bottom:50px}.form-bottom{flex-direction:row;align-items:center}.form-bottom p{font-size:9px}footer{margin:0 5%;gap:18px;flex-wrap:wrap}footer>span:nth-child(2){display:none}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}

/* Textbook-style introduction: one Bopo syllable above each Kai character. */
@font-face{font-family:IntroKai;src:local('STKaitiSC-Regular'),local('Kaiti SC'),local('STKaiti'),local('KaiTi');font-weight:400;font-display:swap}
.reading-intro{padding:45px 0 35px}
.reading-title,.reading-copy{font-family:IntroKai,'Kaiti SC','STKaiti','KaiTi',serif;font-weight:400;letter-spacing:0;font-synthesis:none}
.reading-title{text-align:center;font-size:36px;line-height:2;margin:0 0 23px}
.reading-copy{font-size:27px;max-width:1160px;margin:0 auto}
.reading-copy p{margin:0;line-height:2.65;text-align:justify}
.reading-unit{display:inline-block;white-space:nowrap;vertical-align:baseline}
.reading-intro ruby{display:inline-flex;flex-direction:column-reverse;align-items:center;vertical-align:bottom;min-width:1.32em;line-height:1.1;padding:0 .12em;font-weight:400}
.reading-intro rt{display:block;font-family:Bopo,sans-serif;font-size:.5em;line-height:1.4;letter-spacing:0;text-align:center;padding-bottom:.2em;min-width:100%;color:var(--ink);font-weight:400}
.reading-intro rp{display:none}
.reading-punctuation{display:inline-block;font-size:1em;line-height:1.1;vertical-align:bottom;width:.7em}
.reading-title ruby{min-width:1.4em}
.reading-title rt{font-size:.44em}
.reading-footer{margin-top:29px;display:flex;align-items:center;justify-content:space-between;gap:20px;color:var(--muted);font-size:10px;letter-spacing:.7px}
.reading-footer .text-link{color:var(--ink)}
@media(max-width:900px){.reading-copy{font-size:25px}.reading-intro{padding-top:35px}}
@media(max-width:600px){.reading-intro{padding:30px 0}.reading-title{font-size:29px;margin-bottom:18px}.reading-copy{font-size:23px}.reading-copy p{line-height:2.7;text-align:left}.reading-intro ruby{min-width:1.38em;padding:0 .1em}.reading-intro rt{font-size:.52em}.reading-footer{font-size:8px;gap:10px;letter-spacing:0}.reading-footer .text-link{font-size:10px;gap:10px}}

/* Preserve the typeface's spacing: do not track display specimens negatively. */
.bopo,.ot-specimen{letter-spacing:normal;font-kerning:normal;font-synthesis:none}
.ot-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border-top:1px solid var(--line);border-left:1px solid var(--line)}
.ot-card{padding:22px 25px 27px;border-right:1px solid var(--line);border-bottom:1px solid var(--line);min-width:0}
.ot-card-heading{display:flex;align-items:center;justify-content:space-between;font-size:10px;letter-spacing:1px;color:var(--muted)}
.segmented{display:inline-flex;background:#eaece4;padding:3px;border-radius:4px;gap:2px;letter-spacing:0}
.segmented button{font-size:11px;padding:4px 11px;border-radius:2px;color:var(--muted);line-height:1.3}
.segmented button[aria-pressed=true]{background:var(--paper);color:var(--ink);box-shadow:0 0 0 1px #dfe1d6}
.ot-specimen{height:205px;display:flex;align-items:center;font-size:clamp(33px,3.9vw,58px);line-height:1.35;white-space:nowrap}
.ot-card[data-feature=numr] .ot-specimen,.ot-card[data-feature=dnom] .ot-specimen{font-size:clamp(29px,3vw,45px)}
.ot-card h3{margin:0 0 10px;font-size:17px}.ot-card p{font-size:12px;color:var(--muted);margin:0;line-height:1.8}
.ot-foundation{display:grid;grid-template-columns:1fr 2fr;gap:50px;padding:38px 0 0}
.spacing-specimen{border-right:1px solid var(--line)}#reading-kern{font-size:58px;margin:18px 0 10px;letter-spacing:normal;font-kerning:normal}.kai-caption{font-family:IntroKai,'Kaiti SC',KaiTi,serif;font-size:27px;letter-spacing:12px;color:var(--accent)}
.ot-foundation h3{margin:0 0 12px}.ot-foundation p{font-size:12px;color:var(--muted);max-width:590px}.ot-foundation details{margin-top:24px;border-top:1px solid var(--line);font-size:11px}.ot-foundation summary{cursor:pointer;list-style:none;padding:15px 0;display:flex;justify-content:space-between}.ot-foundation summary::-webkit-details-marker{display:none}.ot-foundation dl{margin:0}.ot-foundation dl>div{display:grid;grid-template-columns:145px 1fr;padding:9px 0;border-top:1px solid var(--line)}.ot-foundation dd{margin:0;color:var(--muted)}
/* Paper-inspired drafting sheet, using original CFF outlines and true metrics. */
.glyph-section-title{position:relative;border:1px solid #d4dbd6;padding:23px 28px 16px;background:repeating-linear-gradient(90deg,transparent 0,transparent 23px,#dfe5df 23px,#dfe5df 24px);overflow:hidden}
.glyph-section-title>.index{background:var(--paper);padding:5px 8px;margin-left:-8px;color:#718977}
.glyph-section-title h2{font-family:Bopo,sans-serif;font-size:clamp(80px,12vw,180px);line-height:1.15;display:flex;justify-content:space-between;margin:20px 0;color:var(--paper);-webkit-text-stroke:1px #7e9b89;text-shadow:2px 3px 0 #b5c4b8;letter-spacing:normal;font-weight:400}
.glyph-summary{display:flex;justify-content:space-between;font-size:9px;letter-spacing:1px;color:#6d8274;background:var(--paper);padding:10px 0}
.glyph-browser{grid-template-columns:1fr 1fr;border-color:#d4dbd6;border-top:0;align-items:start}
.glyph-preview{background:transparent;padding:0;display:block;border-right:1px solid #d4dbd6;min-width:0}
.explorer-toolbar{height:61px;display:flex;justify-content:space-between;align-items:center;padding:0 23px;gap:12px;border-bottom:1px dashed #d4dbd6;font-size:10px}.explorer-toolbar>span{white-space:nowrap}#glyph-name{max-width:130px;overflow:hidden;text-overflow:ellipsis}
.glyph-canvas{background:var(--paper)}#glyph-svg{width:100%;display:block;overflow:visible}
.metric-line{stroke:#bdcabc;stroke-width:.65;stroke-dasharray:3 4}.baseline{stroke:#92ab97;stroke-width:.9}.sidebearing-line{stroke:#c3cdc1;stroke-width:.65;stroke-dasharray:3 4}.width-line,.ruler-tick{stroke:#9bb09d;stroke-width:.6}.metric-label{fill:#7b907e;font-family:'Helvetica Neue',sans-serif;font-size:9px;letter-spacing:.6px}.filled-glyph{fill:var(--ink)}.outline-glyph{fill:none;stroke:var(--ink);stroke-width:1.2;stroke-linejoin:round}
.explorer-controls{display:flex;align-items:center;justify-content:space-between;padding:17px 23px;border-top:1px dashed #d4dbd6;font-size:10px;gap:15px}.explorer-controls label{display:flex;align-items:center;gap:12px}.explorer-controls input{width:100px;accent-color:#718977}.explorer-controls output{min-width:32px}.explorer-controls button{font-size:10px;white-space:nowrap}
.glyph-metrics{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid #d4dbd6;margin:0;padding:21px 23px;gap:10px}.glyph-metrics dt{font-size:8px;letter-spacing:.3px;color:var(--muted)}.glyph-metrics dd{font-family:Bopo,sans-serif;font-size:22px;margin:9px 0 0}
.glyph-list{padding:0;min-width:0}.glyph-tabs{margin:0;gap:3px;background:#eaece4;border-radius:4px;padding:3px}.glyph-tabs button{font-size:10px;border:0;padding:5px 9px;border-radius:2px;color:var(--muted)}.glyph-tabs button[aria-pressed=true]{background:var(--paper);color:var(--ink);box-shadow:0 0 0 1px #dfe1d6}
#glyph-grid{grid-template-columns:repeat(8,minmax(0,1fr));border:0;max-height:550px;overflow-y:auto;scrollbar-width:thin;scrollbar-color:#c3cbbb transparent;align-content:start}
#glyph-grid button{position:relative;padding:8px 2px 15px;height:76px;border-right:1px dashed #d4dbd6;border-bottom:1px dashed #d4dbd6;color:var(--ink);font-size:31px;line-height:1.4}
#glyph-grid button:nth-child(8n){border-right:0}#glyph-grid button.active{background:#e5ebe1;color:var(--ink)}#glyph-grid button:hover{background:#edf0e8}.glyph-cell-character{display:block}.glyph-cell-code{position:absolute;bottom:5px;left:0;right:0;font-family:'Helvetica Neue',sans-serif;font-size:7px;line-height:1;color:#7a8b7d;opacity:0}.active .glyph-cell-code,#glyph-grid button:hover .glyph-cell-code,#glyph-grid button:focus-visible .glyph-cell-code{opacity:1}
#glyph-grid button:focus-visible{outline:2px solid var(--accent);outline-offset:-3px;z-index:1}
.glyph-list-footer{padding:20px 23px;display:flex;justify-content:space-between;color:var(--muted);font-size:9px;gap:10px}.explorer-note{font-size:10px;color:var(--muted);margin:15px 0 0}
@media(max-width:900px){.ot-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.ot-specimen{font-size:48px}.ot-card[data-feature=numr] .ot-specimen,.ot-card[data-feature=dnom] .ot-specimen{font-size:38px}.explorer-toolbar{padding:0 12px;gap:6px}.glyph-tabs button{padding:5px 6px}#glyph-grid{grid-template-columns:repeat(6,minmax(0,1fr))}#glyph-grid button:nth-child(8n){border-right:1px dashed #d4dbd6}#glyph-grid button:nth-child(6n){border-right:0}.explorer-controls{padding:15px 12px}.explorer-controls input{width:65px}.glyph-metrics{padding:18px 12px}.glyph-list-footer{padding:16px 12px}.glyph-list-footer span:last-child{display:none}}
@media(max-width:600px){.ot-grid{grid-template-columns:1fr}.ot-card{padding:20px}.ot-specimen{height:180px;font-size:52px}.ot-card[data-feature=numr] .ot-specimen,.ot-card[data-feature=dnom] .ot-specimen{font-size:38px}.ot-foundation{grid-template-columns:1fr;gap:28px}.spacing-specimen{border-right:0;border-bottom:1px solid var(--line);padding-bottom:25px}#reading-kern{font-size:52px}.glyph-section-title{padding:18px 16px 8px}.glyph-section-title h2{font-size:64px;margin:20px 0}.glyph-summary{font-size:7px;letter-spacing:0}.glyph-browser{grid-template-columns:1fr}.glyph-preview{border-right:0;border-bottom:1px solid #d4dbd6}.explorer-toolbar{padding:0 16px;height:55px}.explorer-controls{padding:15px 16px}.glyph-metrics{padding:18px 16px}.glyph-metrics dd{font-size:20px}#glyph-grid{max-height:390px}.glyph-list-footer span:last-child{display:block}.glyph-list-footer{padding:16px}.explorer-note{font-size:9px;line-height:1.8}}

/* Quiet, alternating reading rhythm: explanation on the left, type on the right. */
.ot-grid{display:block;border-left:0}.ot-card{display:grid;grid-template-columns:1fr 1fr;gap:7%;padding:52px 5%;border-right:0;border-bottom:1px dashed var(--line)}.ot-description{align-self:center}.ot-description h3{margin-top:23px}.ot-description p{max-width:330px;line-height:1.9}.ot-example{min-width:0}.ot-tag{font-size:11px;color:var(--muted);letter-spacing:1px}.ot-specimen{height:auto;min-height:190px;font-size:clamp(42px,4.4vw,64px);padding-top:18px}.ot-card[data-feature=numr] .ot-specimen,.ot-card[data-feature=dnom] .ot-specimen{font-size:clamp(35px,4.2vw,60px)}.glyph-browser{border-top:1px solid #d4dbd6}.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}
.writing-guide{margin-top:15px;border-top:1px solid var(--line);padding-top:22px}.writing-guide-head{display:flex;align-items:center;justify-content:space-between;font-size:12px;color:var(--muted)}.writing-guide-head button{font-size:11px}.writing-guide-head button:hover{color:var(--accent)}#writing-letters{display:grid;grid-template-columns:repeat(4,1fr);margin-top:22px}.writing-letter{padding:0 18px;border-right:1px solid var(--line);text-align:left;min-width:0}.writing-letter:last-child{border:0}.writing-letter-label{display:flex;align-items:center;justify-content:space-between;font-family:Bopo,sans-serif;font-size:22px}.writing-letter-label span{font-family:'PingFang SC',sans-serif;font-size:10px;color:var(--muted)}.writing-letter svg{display:block;width:100%;max-height:245px;margin:7px auto}.writing-rule{stroke:#d4d9cd;stroke-width:.7}.writing-baseline{stroke:#9cae97;stroke-width:1}.writing-step{display:block;font-size:10px;color:var(--muted);padding:8px 0}.is-writing .writing-step,.is-writing .writing-letter-label{color:var(--accent)}.writing-caption{font-size:10px;color:var(--muted);margin:18px 0 0}
.textbook-section{padding-top:85px}.book-stage{padding:42px 28px;background:#e8ebe3;overflow:hidden;border:1px solid #dce1d5}.book-controls{display:flex;justify-content:center;align-items:center;gap:40px;margin-top:24px;font-size:11px}.book-controls button{padding:11px 18px;border:1px solid var(--line)}.book-controls button:disabled{opacity:.35;cursor:default}.book-controls button:hover:not(:disabled){background:#eaede3}.book-controls #book-status{min-width:190px;text-align:center;color:var(--muted)}.book-source-note{font-size:10px;color:var(--muted);text-align:center;margin-top:16px}
#lesson-book{margin:0 auto;max-width:1040px}.textbook-page{background:#fffcf5;color:#303a30;border:1px solid #deddd2;overflow:hidden;container-type:size;box-shadow:inset 10px 0 20px -16px #504f3b}.book-paper{position:relative;width:100%;height:100%;padding:5cqw 6cqw;font-family:IntroKai,'Kaiti SC',KaiTi,serif}.book-running-head{display:flex;justify-content:space-between;border-bottom:1px solid #c7cfbd;padding-bottom:2.5cqw;font-family:'PingFang SC',sans-serif;font-size:1.8cqw;letter-spacing:.1cqw;color:#7a8870}.textbook-page ruby{display:inline-flex;flex-direction:column-reverse;align-items:center;vertical-align:bottom;line-height:1.15;min-width:1.42em;padding:0 .06em}.textbook-page rt{font-family:Bopo,sans-serif;font-size:.48em;line-height:1.5;padding-bottom:.12em;font-weight:400;letter-spacing:normal}.lesson-red{color:#c4513d}.lesson-punctuation{vertical-align:bottom;line-height:1.15}.lesson-vocabulary{display:grid;grid-template-columns:repeat(2,1fr);gap:4cqw 1cqw;font-size:4.5cqw;padding:5cqw 3cqw;border-bottom:1px solid #dce1d4;text-align:center}.lesson-keywords{font-size:4.1cqw;text-align:center;padding:3cqw 0;color:#627256;letter-spacing:0}.lesson-read{font-size:3.8cqw;margin:1.8cqw 0 2cqw}.poem-title{font-family:inherit;font-weight:400;font-size:4.1cqw;text-align:center;margin:0 0 3.5cqw;white-space:nowrap;letter-spacing:0}.poem-title sup{font-size:2cqw}.lesson-poem{font-size:4.2cqw;line-height:1.2;display:flex;flex-direction:column;gap:2.4cqw;align-items:center}.lesson-poem>div{white-space:nowrap}.lesson-attribution{font-size:1.9cqw;border-top:1px solid #d9dbcf;padding-top:2cqw;margin-top:4cqw;line-height:1.5}.book-page-number{position:absolute;bottom:4cqw;left:6cqw;font:2.1cqw Bopo,sans-serif;color:#78856e}
.book-cover{background:#dbe2cf;color:#43533f}.book-cover .book-paper{padding:8cqw}.cover-kicker{font:1.9cqw 'Helvetica Neue',sans-serif;letter-spacing:.25cqw}.cover-name{font-size:15cqw;line-height:1.2;margin-top:10cqw}.cover-pinyin{font-size:10cqw;line-height:1.25;margin-top:6cqw}.cover-foot{position:absolute;bottom:8cqw;font-size:2.7cqw;line-height:1.8}.book-back .cover-pinyin{margin-top:30cqw;font-size:11cqw}.book-back .cover-name{font-size:7cqw;margin-top:7cqw}.book-back p{font-size:3cqw;line-height:1.9}.practice-heading{font-family:inherit;font-size:5.5cqw;font-weight:400;margin:8cqw 0 2cqw}.practice-subtitle{font-size:2.8cqw;color:#819076;margin:0 0 5cqw}.practice-words>div{display:flex;align-items:center;font-size:5cqw;padding:4cqw 0;border-bottom:1px solid #e3e5da}.practice-line{flex:1;margin-left:5cqw;height:6cqw;background:repeating-linear-gradient(to bottom,transparent 0,transparent 1.8cqw,#d9dfd0 1.8cqw,#d9dfd0 1.95cqw)}.practice-sounds,.practice-copy{font-size:8cqw;letter-spacing:normal;margin-top:8cqw;border-bottom:1px solid #cfd6c5;padding:1cqw 0}.practice-copy{font-feature-settings:'ss02' 1;margin-top:3cqw;color:#8b9980}.practice-note{font-family:'PingFang SC',sans-serif;font-size:2cqw;color:#7c8d70;margin-top:3cqw}
@media(max-width:700px){.ot-card{grid-template-columns:1fr;gap:28px;padding:32px 18px}.ot-description h3{margin-top:16px}.ot-specimen{font-size:48px;min-height:160px}.ot-card[data-feature=numr] .ot-specimen,.ot-card[data-feature=dnom] .ot-specimen{font-size:38px}#writing-letters{grid-template-columns:repeat(2,1fr);row-gap:24px}.writing-letter:nth-child(2){border:0}.writing-letter svg{max-height:190px}.book-stage{padding:24px 10px}.book-controls{gap:8px;justify-content:space-between}.book-controls button{padding:10px;font-size:10px}.book-controls #book-status{min-width:0;font-size:10px}.book-source-note{font-size:9px;line-height:1.8}.textbook-section{padding-top:60px}}
/* Keep the entire source page, including its attribution, inside the paper. */
.lesson-vocabulary{padding:3cqw;gap:3cqw 1cqw}.lesson-keywords{padding:2.4cqw 0}.lesson-poem{gap:1.7cqw}.lesson-attribution{margin-top:3cqw}.practice-heading{margin-top:6cqw}.practice-words>div{padding:2.7cqw 0}.practice-sounds{margin-top:5cqw}.practice-copy{margin-top:2cqw}.practice-sounds,.practice-copy{font-size:7.3cqw}
.lesson-vocabulary{font-size:4.2cqw}.poem-title{margin-bottom:2.5cqw}.lesson-poem{gap:.9cqw}.practice-words>div{padding:2cqw 0}
/* Paper's original canvas geometry; no CSS page-edge or inset shadows. */
.textbook-section{background:transparent}.reader{outline-offset:6px;border-top:1px solid var(--line,#d9dcd3);border-bottom:1px solid var(--line,#d9dcd3);scroll-margin-top:90px}.reader-top,.reader-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;font-size:13px;padding:20px 0}.reader-muted,.reader-hint,.reader-footnote{color:#85887f}.reader-modes{display:flex;background:#eaeae5;padding:3px;border-radius:6px}.reader-modes button{border:0;background:transparent;padding:9px 18px;color:#777;cursor:pointer;border-radius:4px;font:inherit}.reader-modes button span{margin-left:8px}.reader-modes button[aria-pressed=true]{background:#fff;color:#292c27;box-shadow:0 1px 3px #00000012}.reader-modes button:disabled{cursor:wait}.reader-stage{height:min(76vw,800px);min-height:380px;position:relative;overflow:visible;container-type:size;display:grid;place-items:center}.reader-frame{width:min(calc(100cqw - 40px),calc((100cqh - 48px)*1.44753),1200px);aspect-ratio:1.44753;position:relative}.paper-book{position:absolute;inset:0;touch-action:pan-y pinch-zoom}.paper-book>[data-magazine-layer]{position:absolute;top:-27.975%;left:-27.975%;width:155.95%;height:155.95%;display:block;pointer-events:none}.paper-book>canvas{opacity:0}.paper-book[data-magazine-state=ready]>canvas{opacity:1}.paper-book>[data-magazine-hit-area]{cursor:grab}.paper-book>[data-magazine-hit-area]:active{cursor:grabbing}.paper-book.leaving,.paper-book.leaving *{pointer-events:none!important}.reader-loading{position:absolute;inset:0;display:grid;place-items:center;pointer-events:none;font-size:13px;color:#888}.reader-loading[hidden]{display:none}.reader-navigation{display:flex;align-items:center;gap:8px}.reader-navigation button,#book-detail{background:none;border:0;padding:12px 16px;font:inherit;cursor:pointer}.reader-navigation button:hover,#book-detail:hover{background:#eeeee8}.reader-navigation button:disabled{opacity:.25;cursor:default}#book-status{min-width:110px;text-align:center;font-variant-numeric:tabular-nums}.reader-footnote{display:flex;justify-content:space-between;gap:20px;font-size:11px;line-height:1.8;margin-top:20px}.reader-footnote a{color:inherit}.reader-bottom> :first-child,.reader-bottom> :last-child{flex:1}.reader-bottom> :last-child{text-align:right}.reader button:focus-visible{outline:2px solid #7a9276;outline-offset:3px}#book-comparison{width:min(1500px,96vw);max-width:96vw;height:92vh;max-height:92vh;padding:0;border:1px solid #d9dcd3;background:#f7f7f2;color:#30372d}#book-comparison::backdrop{background:#20251d90;backdrop-filter:blur(5px)}.comparison-head,.comparison-bottom{display:flex;justify-content:space-between;align-items:center;gap:20px;padding:16px 24px;font-size:13px;background:#f7f7f2}.comparison-head{position:sticky;top:0;z-index:1;border-bottom:1px solid #ddd}.comparison-head button,.comparison-bottom button{background:none;border:0;font:inherit;padding:12px;cursor:pointer}.comparison-pages{display:grid;grid-template-columns:1fr 1fr;gap:20px;padding:24px}.comparison-pages figure{margin:0;min-width:0}.comparison-pages figcaption{margin-bottom:16px;color:#777;font-size:12px}.comparison-pages img{width:100%;height:auto;display:block;border:1px solid #e8e8e3}.comparison-bottom{position:sticky;bottom:0;border-top:1px solid #ddd}.comparison-bottom span{color:#888;font-size:11px}
@media(max-width:700px){.reader-top{align-items:flex-start;flex-direction:column;gap:14px}.reader-top,.reader-bottom{font-size:12px}.reader-stage{height:125vw;min-height:0;max-height:700px}.reader[data-layout=single] .reader-frame{width:min(calc(100cqw - 32px),calc((100cqh - 48px)*.65));aspect-ratio:.65;margin-bottom:-3%}.paper-book[data-mode=single]>[data-magazine-layer]{inset:0;width:100%;height:100%;transform:scale(1.3);pointer-events:auto;touch-action:pan-y pinch-zoom}.reader-hint{display:none}.reader-bottom{gap:8px}.reader-bottom> :last-child{flex:initial}.reader-footnote{flex-direction:column;gap:5px}.comparison-pages{gap:8px;padding:12px;min-width:850px}.comparison-bottom span{display:none}.comparison-head{font-size:11px;padding:8px 12px}}
#lesson-book{max-width:none;outline:none}
/* Match the reference: a complete spread at roughly 85% of viewport height. */
@media(min-width:701px){.reader-stage{width:100%;height:90svh;min-height:0;max-height:none;aspect-ratio:auto}.reader-frame{width:min(96cqw,123svh);max-width:none}}

#reader-pages{scroll-margin-top:64px}

/* Curl extends beyond the resting page bounds; keep it visible without blocking controls. */
.reader-top,.reader-bottom{position:relative;z-index:2}

.reader-modes[hidden],.comparison-pages figure[hidden]{display:none}.is-specimen .comparison-pages{grid-template-columns:1fr;min-width:0;max-width:1000px;margin:auto}

footer{flex-wrap:wrap}footer .icp-filing{flex-basis:100%;text-align:center;font-size:12px;color:var(--muted);padding:8px 0 4px}footer .icp-filing:hover{text-decoration:underline}

/* Handwritten brand mark: crop source whitespace in layout, preserve original artwork. */
header .logo{position:relative;width:112px;height:61px;flex:none;overflow:hidden;mix-blend-mode:multiply}
header .logo img{position:absolute;width:127.1%;height:auto;max-width:none;left:-15.32%;top:-15.56%;filter:contrast(1.2)}
@media(max-width:600px){header .logo{width:88px;height:48px}header nav{gap:14px}}