/* Editorial library front page. Independent of per-article teaching interactions. */
.library-page{min-height:100vh;background:var(--bg);color:var(--ink)}
.library-page [hidden]{display:none!important}
.library-page a:focus-visible,.library-page button:focus-visible,.library-page input:focus-visible{outline:2px solid var(--accent);outline-offset:4px}
.library-header{max-width:1340px;margin:0 auto;padding:22px 40px;display:flex;gap:38px;align-items:center;border-bottom:1px solid var(--line)}
.library-logo{display:flex;align-items:center;gap:13px;color:var(--ink);text-decoration:none;font-size:19px;font-weight:760;letter-spacing:.025em;line-height:1.3;white-space:nowrap}
.library-logo:hover{opacity:1;color:var(--brand)}
.library-logo-mark{display:grid;place-items:center;height:39px;width:39px;border-radius:50%;border:1px solid var(--brand);font-size:17px;color:var(--brand);font-weight:700}
.library-logo small{display:block;font-size:9px;letter-spacing:.19em;color:var(--muted);margin-top:3px;font-weight:600}
.library-header nav{margin-left:auto;display:flex;align-items:center;gap:31px}
.library-header nav a{color:var(--muted);font-size:13px;text-decoration:none;white-space:nowrap;font-weight:530}
.library-header nav a[aria-current],.library-header nav a:hover{color:var(--brand)}
.library-theme{width:36px;height:36px;border:1px solid var(--line);border-radius:50%;background:transparent;color:var(--ink);cursor:pointer;font-size:20px}
.library-wrap{max-width:1220px;margin:0 auto;padding:0 42px}
.library-hero{max-width:770px;padding:100px 0 83px}
.library-kicker{font-size:12px;letter-spacing:.12em;color:var(--brand);font-weight:750;display:flex;gap:12px;align-items:center;margin:0 0 23px}
.library-kicker>span:not(.library-kicker-mark){color:var(--muted)}
.library-kicker-mark{width:20px;height:1px;background:var(--accent);display:inline-block}
.library-hero h1{font-family:"Iowan Old Style","Noto Serif TC","Songti TC",serif;font-size:clamp(48px,5.3vw,74px);font-weight:670;letter-spacing:-.055em;line-height:1.36;margin:0;text-wrap:balance}
.library-hero h1 em{font-style:normal;color:var(--brand)}
.library-intro{max-width:570px;font-size:16px;line-height:1.95;color:var(--muted);margin:23px 0 40px}
.library-search-wrap{max-width:620px}
.library-search-wrap>label{display:block;color:var(--ink);font-size:13px;letter-spacing:.03em;font-weight:730;margin-bottom:12px}
.library-search-field{height:60px;display:flex;align-items:center;gap:10px;padding:0 15px 0 19px;border:1px solid var(--line);background:var(--surface);box-shadow:0 6px 25px rgba(22,45,34,.035);border-radius:10px;transition:border-color .15s,box-shadow .15s}
.library-search-field:focus-within{border-color:var(--brand);box-shadow:0 0 0 3px color-mix(in srgb,var(--brand) 12%,transparent)}
.library-search-field>span{color:var(--brand);font-size:27px;font-family:serif;line-height:1}
.library-search-field .searchbox{min-width:0;flex:1;background:transparent;border:0;font-size:15px;padding:11px 0;box-shadow:none;outline:none}
.library-search-field kbd{border:1px solid var(--line);border-radius:5px;padding:0 8px;line-height:24px;font-size:12px;color:var(--muted);font-family:inherit}
.library-search-wrap>p{font-size:12px;margin:9px 0;color:var(--muted);line-height:1.5}
.library-search-results{background:var(--surface);border-radius:10px;max-height:370px;overflow:auto}
.library-search-results:not(:empty){border:1px solid var(--line);margin-top:12px;padding:5px}
.library-search-results .result{display:block;padding:12px 15px;border-bottom:1px solid var(--line);border-radius:6px}
.library-search-results .result:last-child{border-bottom:none}
.library-search-results .result:hover{background:var(--brand-light);opacity:1}
.library-search-results .result b{font-size:14px}.library-search-results .result small{display:block;font-size:12px;max-width:72ch;line-height:1.6}
.library-resume{margin-top:24px;display:flex;align-items:center;gap:24px;justify-content:space-between;max-width:620px;padding:15px 19px;border-left:2px solid var(--accent);background:var(--brand-light);color:var(--ink);text-decoration:none}
.library-resume small{display:block;color:var(--muted);font-size:11px}
.library-resume strong{font-size:14px;display:block;line-height:1.55;font-weight:700}
.library-section{border-top:1px solid var(--line);padding:50px 0 88px}
.library-section-heading{display:flex;justify-content:space-between;align-items:flex-end;gap:20px;margin-bottom:27px}
.library-section-heading h2{font-family:"Iowan Old Style","Noto Serif TC","Songti TC",serif;font-size:32px;letter-spacing:-.035em;line-height:1.4;margin:6px 0 0;font-weight:680}
.library-section-heading>p{font-size:13px;margin:0 0 3px;color:var(--muted)}
.library-overline{font-size:10px;font-weight:750;letter-spacing:.17em;color:var(--accent);line-height:1.4;margin:0}
.library-filters{display:flex;align-items:center;flex-wrap:wrap;gap:8px;margin:0 0 21px}
.library-filters button{padding:7px 15px;border:1px solid var(--line);border-radius:50px;background:transparent;color:var(--muted);font-size:12px;cursor:pointer;font-family:inherit;line-height:1.5}
.library-filters button:hover{border-color:var(--brand);color:var(--brand)}
.library-filters button.is-active{background:var(--brand);border-color:var(--brand);color:var(--surface)}
.library-grid{display:grid;grid-template-columns:1.15fr 1fr;grid-auto-flow:row;gap:16px}
.library-card{display:flex;flex-direction:column;justify-content:space-between;min-height:205px;padding:28px 31px;text-decoration:none;background:var(--surface);border:1px solid var(--line);border-radius:13px;color:var(--ink);transition:transform .16s,box-shadow .16s,border-color .16s}
.library-card:hover{opacity:1;transform:translateY(-2px);box-shadow:0 12px 35px rgba(28,58,41,.08);border-color:color-mix(in srgb,var(--brand) 38%,var(--line))}
.library-card-feature{grid-row:span 2;min-height:426px;background:linear-gradient(135deg,var(--surface),var(--brand-light))}
.library-card-kind{font-size:11px;letter-spacing:.07em;color:var(--brand);font-weight:700;line-height:1.5}
.library-card-middle{display:block;margin:18px 0 auto;max-width:560px}
.library-card-middle strong{display:block;font-family:"Iowan Old Style","Noto Serif TC","Songti TC",serif;font-size:24px;letter-spacing:-.027em;line-height:1.55;font-weight:680;color:var(--ink)}
.library-card-middle>span{display:block;font-size:13px;line-height:1.85;color:var(--muted);margin-top:10px}
.library-card-feature .library-card-middle{margin:auto 0}
.library-card-feature .library-card-middle strong{font-size:clamp(28px,3vw,40px);line-height:1.47;max-width:12em}
.library-card-bottom{border-top:1px solid var(--line);padding-top:15px;display:flex;align-items:center;justify-content:space-between;font-size:12px;color:var(--brand);margin-top:27px;font-weight:700}
.library-card-bottom>span:last-child{font-size:19px}
.library-filter-empty{color:var(--muted);font-size:14px;margin:28px 0}
.library-paths{padding-bottom:100px}
.library-path-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.library-path{display:block;padding:35px 36px 29px;text-decoration:none;background:var(--brand-light);border:1px solid var(--line);color:var(--ink);border-radius:10px}
.library-path:nth-child(2){background:var(--surface)}
.library-path:hover{opacity:1;border-color:var(--brand)}
.library-path-number{font-size:10px;letter-spacing:.13em;color:var(--brand);font-weight:700}
.library-path h3{font-family:"Iowan Old Style","Noto Serif TC","Songti TC",serif;font-size:26px;line-height:1.5;margin:17px 0 8px}
.library-path p{font-size:14px;line-height:1.85;color:var(--muted);max-width:37ch;min-height:4em;margin:0 0 29px}
.library-path>span:last-child{display:flex;gap:8px;align-items:center;font-weight:750;color:var(--brand);font-size:13px}
.library-footer{padding:32px 0 45px;border-top:1px solid var(--line);display:flex;align-items:flex-start;justify-content:space-between;gap:30px;margin:0}
.library-footer>div{display:grid;gap:5px}.library-footer strong{font-size:15px}.library-footer>div span{font-size:12px;color:var(--muted)}
.library-footer nav{display:flex;flex-wrap:wrap;gap:22px}.library-footer nav a{color:var(--muted);font-size:12px;text-decoration:none}
.library-footer nav a:hover{color:var(--brand)}
.library-grid.is-filtered .library-card-feature{grid-row:auto;min-height:205px}
.library-grid.is-filtered .library-card-feature .library-card-middle{margin:18px 0 auto}
.library-grid.is-filtered .library-card-feature .library-card-middle strong{font-size:24px}
@media(max-width:850px){.library-header{padding:18px 24px;gap:16px;flex-wrap:wrap}.library-header nav{gap:16px;order:3;width:100%;overflow-x:auto;margin:0}.library-theme{margin-left:auto}.library-wrap{padding:0 27px}.library-hero{padding:74px 0 65px}.library-grid{grid-template-columns:1fr}.library-card-feature{grid-row:auto;min-height:310px}.library-card{min-height:205px}.library-card-feature .library-card-middle{margin:18px 0 auto}.library-section{padding-bottom:60px}}
@media(max-width:560px){.library-header{padding:16px 19px}.library-header nav{gap:21px}.library-header nav a{font-size:12px}.library-wrap{padding:0 20px}.library-hero{padding:57px 0 52px}.library-hero h1{font-size:clamp(40px,11vw,56px)}.library-intro{font-size:14px;margin-bottom:28px}.library-search-field{height:54px}.library-section{padding:34px 0 55px}.library-section-heading{display:block}.library-section-heading>p{margin-top:9px}.library-section-heading h2{font-size:28px}.library-filters{flex-wrap:nowrap;overflow-x:auto;padding:1px 0 8px;margin-right:-20px}.library-filters button{white-space:nowrap}.library-card,.library-card-feature{padding:22px 23px;min-height:215px}.library-card-middle strong{font-size:22px}.library-card-feature .library-card-middle strong{font-size:28px}.library-path-grid{grid-template-columns:1fr}.library-path{padding:27px 25px}.library-path p{min-height:0}.library-footer{display:block}.library-footer nav{margin-top:20px;gap:15px}}
@media(prefers-reduced-motion:reduce){.library-card,.library-search-field{transition:none}.library-card:hover{transform:none}}


/* Knowledge atlas: substantive cross-article routes before the article shelf. */
.library-atlas{display:grid;grid-template-columns:1.25fr .85fr;gap:44px;margin:0 0 84px;padding:43px 47px;background:var(--brand-light);border:1px solid var(--line);border-radius:15px}
.library-atlas-copy h2{font-family:"Iowan Old Style","Noto Serif TC","Songti TC",serif;font-size:clamp(28px,3vw,39px);letter-spacing:-.035em;line-height:1.5;margin:13px 0 17px}
.library-atlas-copy>p:not(.library-overline){font-size:14px;line-height:1.95;max-width:54ch;color:var(--muted);margin:0 0 20px}
.library-atlas-cta{display:inline-flex;align-items:center;gap:15px;color:var(--brand);font-size:13px;font-weight:760;text-decoration:none;border-bottom:1px solid currentColor;padding-bottom:3px}
.library-atlas-steps{display:grid;gap:0;align-content:center}
.library-atlas-steps>div{padding:12px 0 14px 20px;border-left:1px solid var(--line);border-bottom:1px solid var(--line);display:grid;gap:2px}
.library-atlas-steps>div:last-child{border-bottom:0}
.library-atlas-steps span{font-size:10px;letter-spacing:.1em;color:var(--brand);font-weight:700}
.library-atlas-steps strong{font-size:15px;color:var(--ink);font-weight:730}
.library-atlas-steps small{color:var(--muted);font-size:11px;line-height:1.6}
.library-path-grid{grid-template-columns:repeat(3,minmax(0,1fr))}
@media(max-width:850px){.library-atlas{grid-template-columns:1fr;gap:20px;padding:30px}.library-atlas-steps{grid-template-columns:1fr 1fr}.library-atlas-steps>div{padding:12px;border-bottom:1px solid var(--line)}.library-path-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.library-atlas{padding:26px 22px;margin-bottom:55px}.library-atlas-steps{grid-template-columns:1fr}.library-path-grid{grid-template-columns:1fr}.library-atlas-copy h2{font-size:29px}}