:root{--ink:#1f2c28;--muted:#69746e;--bg:#f5f4ef;--paper:#fffefa;--line:#deded5;--forest:#34574b}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-family:'DM Sans','Noto Sans JP',-apple-system,BlinkMacSystemFont,sans-serif;line-height:1.85}a{color:inherit;text-decoration:none}a:focus-visible{outline:3px solid #9cc1a9;outline-offset:3px}header{border-bottom:1px solid var(--line);background:#f9f8f3}nav,.container{width:min(1080px,calc(100% - 40px));margin:auto}nav{display:flex;align-items:center;justify-content:space-between;padding:22px 0;gap:18px;flex-wrap:wrap}.brand{font-family:'Playfair Display',Georgia,serif;font-size:24px;color:var(--forest)}.nav-right{display:flex;align-items:center;gap:20px;flex-wrap:wrap;font-size:12px}.nav-right a:hover,.toplink:hover{color:var(--forest)}.lang{display:flex;gap:5px}.lang button{font-size:11px;padding:6px 9px;border-radius:20px;background:transparent;border:1px solid var(--line);cursor:pointer}.lang button.active{background:var(--forest);color:white}.container{padding:60px 0 90px}.eyebrow{color:var(--forest);font-size:11px;font-weight:700;letter-spacing:.2em;text-transform:uppercase}.headline{font:400 clamp(32px,4vw,55px)/1.3 'Playfair Display','Noto Sans JP',serif;margin:14px 0}.lead{color:var(--muted);font-size:14px;max-width:720px;margin-bottom:36px}.series-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:25px 0 40px}.series{padding:28px;background:var(--paper);border:1px solid var(--line);border-radius:5px}.series small{color:var(--forest);font-size:10px;text-transform:uppercase;letter-spacing:.12em}.series h2{font:400 24px 'Playfair Display','Noto Sans JP',serif;margin:7px 0}.series p{font-size:13px;color:var(--muted);margin:0 0 14px}.series .count{font-size:12px;color:var(--forest)}.series a{font-size:12px;border-bottom:1px solid var(--forest)}.section-h{font:400 27px 'Playfair Display','Noto Sans JP',serif;margin:40px 0 14px}.lessons{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.lesson{display:block;background:var(--paper);border:1px solid var(--line);padding:20px 22px;border-radius:4px}.lesson:hover,.series:hover{border-color:#6d9686}.lesson .num{display:block;color:var(--forest);font-size:11px;font-weight:700;margin-bottom:7px}.lesson strong{font-size:14px;line-height:1.55;font-weight:600}.lesson .date{display:block;font-size:11px;color:var(--muted);margin-top:9px}.filterbar{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:20px}.filterbar button{background:transparent;border:1px solid var(--line);padding:8px 13px;cursor:pointer;border-radius:22px;font-size:12px}.filterbar button.active{background:var(--forest);border-color:var(--forest);color:#fff}input[type=search]{padding:12px 16px;border:1px solid var(--line);background:white;width:100%;font:inherit;font-size:14px;margin-bottom:16px;border-radius:4px}.breadcrumb{color:var(--muted);font-size:12px;margin-bottom:24px}.breadcrumb a{text-decoration:underline;text-underline-offset:3px}.sheet{background:var(--paper);border:1px solid var(--line);padding:clamp(20px,5vw,62px);max-width:860px;margin:0 auto}.sheet h1{font:400 clamp(27px,3.6vw,42px)/1.45 'Playfair Display','Noto Sans JP',serif;margin:12px 0}.sheet .meta{font-size:12px;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:22px}.copy{font-size:15px;line-height:2.05;overflow-wrap:anywhere}.copy img{max-width:100%;width:auto;height:auto;display:block;margin:16px auto}.copy figure{max-width:100%;margin:24px 0}.copy h2,.copy h3{line-height:1.5;margin-top:32px}.copy a{color:var(--forest);text-decoration:underline}.copy iframe{max-width:100%}.copy table{display:block;overflow-x:auto}.copy pre{white-space:pre-wrap}.copy .wp-block-image{margin:24px auto}.notice{font-size:12px;color:var(--muted);background:#edf0e9;padding:14px 20px;border-left:3px solid var(--forest);margin:22px 0}.pager{display:flex;gap:12px;justify-content:space-between;max-width:860px;margin:25px auto}.pager a,.cta a{padding:12px 18px;border:1px solid var(--forest);font-size:12px;color:var(--forest)}.cta{text-align:center;border-top:1px solid var(--line);margin-top:50px;padding:40px 0}.cta p{color:var(--muted);font-size:14px}footer{text-align:center;border-top:1px solid var(--line);font-size:12px;color:var(--muted);padding:30px}@media(max-width:690px){nav{padding:16px 0}.series-grid,.lessons{grid-template-columns:1fr}.container{padding-top:35px}.sheet{padding:22px 18px}.nav-right{gap:12px}}
/* V22 editorial learning design */
.series-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.series{transition:transform .18s ease,border-color .18s ease}.series:hover{transform:translateY(-3px);border-color:#728574}.series h2{font-size:clamp(20px,2.3vw,27px)}.sheet{border-radius:3px}.sheet .copy{line-height:2.1;letter-spacing:.015em}.sheet .copy p{margin:1.1em 0}.sheet .copy img{border-radius:3px}.sheet .meta{margin-bottom:26px}.lesson-end{max-width:860px;margin:0 auto 65px;padding:30px 0}.end-kicker{font-size:11px;letter-spacing:.2em;color:#718174}.lesson-next{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin:16px 0}.lesson-next a{display:flex;align-items:center;min-height:75px;border:1px solid var(--line);background:#fff;padding:18px;font-size:13px;line-height:1.7;text-decoration:none}.lesson-next a:hover{border-color:var(--forest)}.back-library{display:inline-block;font-size:12px;color:var(--forest);margin:8px 0 25px;text-decoration:underline;text-underline-offset:4px}.lesson-cta{border-top:1px solid var(--line);padding:38px 24px;text-align:center;background:#eaece6}.lesson-cta h2{font:400 27px/1.4 'Playfair Display','Noto Sans JP',serif;margin:0 0 12px}.lesson-cta p{font-size:13px;color:var(--muted);line-height:1.9;margin:0 auto 22px;max-width:550px}.lesson-cta a{display:inline-block;background:var(--forest);color:#fff;padding:14px 22px;text-decoration:none;font-size:13px}@media(max-width:690px){.series-grid{grid-template-columns:1fr}.lesson-end{padding:20px 12px}.lesson-next{grid-template-columns:1fr}}

/* V23 — Pivo editorial design system: typographic rhythm, readable notation */
:root{--ink:#252823;--muted:#656960;--bg:#f7f6f2;--paper:#fffefa;--line:#e0dfd8;--forest:#43584c;--accent:#967d58}
html{scroll-behavior:smooth}body{font-family:'Noto Sans JP','DM Sans',sans-serif;font-weight:400;-webkit-font-smoothing:antialiased;line-height:1.8}
header{background:rgba(255,254,250,.97)}nav{padding:19px 0}.brand{color:var(--ink);font-size:23px;letter-spacing:-.025em}.nav-right{font-size:12px;letter-spacing:.025em}
.container{padding-top:76px}.eyebrow,.end-kicker{color:var(--accent);font-weight:600;letter-spacing:.19em}.headline{font-size:clamp(34px,4.5vw,58px);line-height:1.38;letter-spacing:-.035em;color:var(--ink);margin:20px 0 22px}.lead{font-size:clamp(14px,1.25vw,16px);line-height:2;max-width:750px}
.series-grid{gap:18px;margin:40px 0 70px}.series{padding:clamp(25px,3.5vw,40px);border-radius:2px;box-shadow:0 6px 25px rgba(34,35,28,.025)}.series small{color:var(--accent);font-size:11px;font-weight:600}.series h2{font-family:'Noto Sans JP',sans-serif;font-size:clamp(22px,2.5vw,28px);font-weight:500;line-height:1.5;margin:16px 0 10px}.series p{font-size:14px;line-height:1.95}.series a{font-size:13px;text-underline-offset:5px}
.section-h{font-family:'Noto Sans JP',sans-serif;font-size:clamp(23px,2.4vw,30px);font-weight:500;letter-spacing:-.03em;margin:55px 0 24px}.filterbar button{font-family:inherit;font-size:13px;padding:9px 17px}.lesson{border-radius:2px;padding:26px 28px;transition:border-color .2s,box-shadow .2s,transform .2s}.lesson:hover{transform:translateY(-2px);box-shadow:0 8px 26px rgba(35,38,30,.045)}.lesson .num{color:var(--accent);font-size:11px;letter-spacing:.05em}.lesson strong{display:block;font-size:15px;line-height:1.8;font-weight:500}.lesson .date{color:#878b82}
.sheet{max-width:900px;padding:clamp(26px,6vw,78px);box-shadow:0 12px 45px rgba(37,40,35,.035)}.sheet h1{font-family:'Noto Sans JP',sans-serif;font-size:clamp(27px,3vw,38px);font-weight:600;line-height:1.55;letter-spacing:-.04em;margin:16px 0 24px}.sheet .meta{font-size:12px;letter-spacing:.04em;padding-bottom:26px;margin-bottom:40px}.copy,.sheet .copy{font-size:clamp(16px,1.2vw,17px);line-height:2.15;letter-spacing:.015em;color:#2b2e29}.sheet .copy p{margin:1.5em 0}.copy h2{font-family:'Noto Sans JP',sans-serif;font-size:clamp(21px,2vw,26px);font-weight:600;line-height:1.65;letter-spacing:-.03em;margin:3em 0 1em;padding-bottom:.5em;border-bottom:1px solid var(--line)}.copy h3{font-family:'Noto Sans JP',sans-serif;font-size:clamp(18px,1.65vw,21px);font-weight:600;line-height:1.7;margin:2.4em 0 .8em}.copy h4{font-size:17px;margin:2em 0 .75em}.copy img{max-width:100%;height:auto;margin:30px auto;border-radius:2px}.copy figure,.copy .wp-block-image{margin:38px auto}.copy figcaption{font-size:12px;color:var(--muted);text-align:center;line-height:1.8}.copy ul,.copy ol{padding-left:1.6em}.copy li{padding-left:.2em;margin:.6em 0}.copy blockquote{border-left:2px solid var(--accent);padding:8px 0 8px 24px;margin:35px 0;color:var(--muted)}.copy a{text-underline-offset:4px}.copy table{max-width:100%;margin:28px 0;border-collapse:collapse}.copy td,.copy th{border:1px solid var(--line);padding:10px 15px}.copy iframe{display:block;margin:28px auto}.notice{background:#f1f0ea;border-left-color:var(--accent);font-size:13px;line-height:1.9}
.lesson-end{max-width:900px}.lesson-next a{background:var(--paper);padding:22px 24px;font-size:14px}.lesson-cta{background:#eeede7;padding:48px 25px}.lesson-cta h2{font-family:'Noto Sans JP',sans-serif;font-weight:500;font-size:clamp(21px,2.4vw,27px)}.lesson-cta p{font-size:14px}.lesson-cta a{background:var(--ink);font-weight:500;letter-spacing:.02em}.lesson-cta a:hover{background:var(--forest)}
@media(max-width:690px){.container{width:calc(100% - 32px);padding-top:42px}.headline{font-size:33px}.series-grid{margin:30px 0 48px}.series{padding:26px}.sheet{padding:32px 23px}.sheet h1{font-size:26px}.sheet .copy{font-size:16px;line-height:2.05}.copy h2{margin-top:2.5em}.lesson{padding:21px}.lesson strong{font-size:14px}.lesson-end{padding:18px 0}.nav-right{gap:10px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.lesson,.series{transition:none}}


/* v64 | Readability scale: mobile-first, scoped to Learning Library. */
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body { font-size: 16px; }
.nav-right { font-size: 14px; }
.lang button { font-size: 13px; min-width: 36px; min-height: 36px; }
.breadcrumb, .sheet .meta { font-size: 13px; }
.lead { font-size: clamp(15px, 1.3vw, 17px); line-height: 1.85; }
.series p { font-size: 15px; line-height: 1.85; }
.series a, .series .count { font-size: 14px; }
.lesson strong { font-size: 16px; line-height: 1.65; }
.lesson .num, .lesson .date { font-size: 12px; }
.filterbar button { font-size: 14px; min-height: 40px; }
input[type=search] { font-size: 16px; }
.sheet h1 { font-size: clamp(29px, 3.5vw, 42px); line-height: 1.4; }
.sheet .copy { font-size: 16px; line-height: 1.95; letter-spacing: .012em; }
.sheet .copy h2 { font-size: clamp(21px, 2.4vw, 27px); line-height: 1.5; }
.sheet .copy h3 { font-size: clamp(18px, 2vw, 22px); line-height: 1.5; }
.sheet .copy figcaption, .notice, .article-language-note { font-size: 14px; line-height: 1.8; }
.lesson-next a, .back-library, .pager a, .cta a, .lesson-cta a { font-size: 14px; line-height: 1.6; }
.lesson-cta p, .cta p { font-size: 15px; }
.lesson-cta h2 { font-size: clamp(23px, 2.5vw, 28px); }
@media (max-width: 690px) {
  nav,.container { width: min(100% - 32px, 1080px); }
  .nav-right { font-size: 13px; gap: 10px; }
  .container { padding-top: 36px; }
  .headline { font-size: clamp(30px, 8vw, 40px); line-height: 1.35; }
  .sheet { padding: 26px 20px; }
  .sheet .copy { font-size: 16px; line-height: 1.9; }
  .sheet h1 { font-size: clamp(27px, 7vw, 34px); }
  .series { padding: 26px 23px; }
  .lesson { padding: 21px 20px; }
  .lesson-cta { padding: 34px 18px; }
}


/* v65: Reading-first editorial layout — confined to Learning article pages. */
body:has(article.sheet) .container { max-width: 1050px; }
body:has(article.sheet) article.sheet {max-width: 820px;padding:clamp(28px,5.4vw,66px);}
body:has(article.sheet) .sheet h1 {font-size:clamp(28px,3vw,39px);line-height:1.48;letter-spacing:-.025em;overflow-wrap:break-word;}
body:has(article.sheet) .sheet .copy {font-size:17px;line-height:1.94;letter-spacing:.012em;overflow-wrap:break-word;}
body:has(article.sheet) .sheet .copy p {margin:1.2em 0;}
body:has(article.sheet) .sheet .copy h2 {font-size:clamp(22px,2.4vw,27px);line-height:1.52;margin:2.1em 0 .7em;}
body:has(article.sheet) .sheet .copy h3 {font-size:clamp(19px,2vw,22px);line-height:1.55;margin:1.8em 0 .65em;}
body:has(article.sheet) .sheet .copy h4 {font-size:18px;line-height:1.55;}
body:has(article.sheet) .sheet .copy figure,body:has(article.sheet) .sheet .copy .wp-block-image {margin:26px auto;}
body:has(article.sheet) .sheet .copy img {width:auto;max-width:100%;height:auto;object-fit:contain;margin:22px auto;}
body:has(article.sheet) .sheet .copy figcaption {font-size:14px;line-height:1.7;}
body:has(article.sheet) .sheet .copy iframe,body:has(article.sheet) .sheet .copy video {max-width:100%;}
body:has(article.sheet) .sheet .copy .wp-block-embed__wrapper {max-width:100%;overflow:hidden;}
body:has(article.sheet) .sheet .copy .caption-box {margin:25px 0;padding:0;max-width:100%;}
body:has(article.sheet) .sheet .copy .caption-box-label {font-size:16px;line-height:1.7;font-weight:600;}
body:has(article.sheet) .sheet .copy .caption-box-content {overflow-wrap:anywhere;}
body:has(article.sheet) .sheet .copy .caption-box-content p {margin:.75em 0;}
/* WordPress fz utility classes previously depended on missing styles: format actual chord examples deliberately. */
body:has(article.sheet) .sheet .copy .fz-40px {font-size:clamp(24px,4vw,36px);line-height:1.5;}
body:has(article.sheet) .sheet .copy .fz-36px {font-size:clamp(23px,3.6vw,33px);}
body:has(article.sheet) .sheet .copy .fz-32px {font-size:clamp(21px,3.2vw,30px);}
body:has(article.sheet) .sheet .copy .fz-28px {font-size:clamp(20px,2.8vw,26px);}
body:has(article.sheet) .sheet .copy .fz-22px {font-size:20px;}
body:has(article.sheet) .sheet .copy .fz-20px {font-size:18px;}
body:has(article.sheet) .sheet .copy .fz-12px {font-size:12px;}
body:has(article.sheet) .sheet .copy table {font-size:15px;line-height:1.65;max-width:100%;overflow-x:auto;}
body:has(article.sheet) .sheet .copy .wp-block-columns {max-width:100%;}
@media(max-width:690px){
 body:has(article.sheet) .container {width:calc(100% - 24px);padding-top:29px;}
 body:has(article.sheet) article.sheet {padding:26px 18px;max-width:100%;}
 body:has(article.sheet) .sheet h1 {font-size:clamp(25px,6.6vw,31px);line-height:1.45;}
 body:has(article.sheet) .sheet .copy {font-size:16.5px;line-height:1.9;letter-spacing:.008em;}
 body:has(article.sheet) .sheet .copy h2 {font-size:22px;margin:1.8em 0 .7em;}
 body:has(article.sheet) .sheet .copy h3 {font-size:19px;margin:1.6em 0 .6em;}
 body:has(article.sheet) .sheet .copy figure,body:has(article.sheet) .sheet .copy .wp-block-image {margin:22px auto;}
 body:has(article.sheet) .sheet .copy img {margin:18px auto;}
 body:has(article.sheet) .sheet .copy .caption-box-label {font-size:15px;}
 body:has(article.sheet) .sheet .copy .fz-40px {font-size:clamp(23px,7vw,32px);}
 body:has(article.sheet) .sheet .copy .fz-36px {font-size:clamp(22px,6vw,30px);}
 body:has(article.sheet) .sheet .copy .fz-32px {font-size:clamp(20px,5.5vw,28px);}
 body:has(article.sheet) .sheet .copy [style*="font-size: 40px"] {font-size:30px!important;}
 body:has(article.sheet) .sheet .copy table {font-size:14px;}
 body:has(article.sheet) .lesson-next a {min-height:62px;}
}