:root{
  --navy:#0F2A4A; --blue:#2B6CE5; --teal:#12A39A; --bg:#F4F8FC; --card:#FFFFFF; --text:#122033; --muted:#64748B; --line:#D7E2F0; --yellow:#FFCF55; --red:#B42318;
}
*{box-sizing:border-box} html{scroll-behavior:smooth} body{margin:0;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Noto Sans TC","PingFang TC","Microsoft JhengHei",sans-serif;line-height:1.75} a{color:var(--blue)}
body.dark{--bg:#081827;--card:#0D2238;--text:#E6EEF8;--muted:#AFC0D2;--line:#1F3B58;--navy:#06111D}
.app{display:grid;grid-template-columns:360px 1fr;min-height:100vh}.sidebar{position:sticky;top:0;height:100vh;overflow:auto;background:linear-gradient(180deg,var(--navy),#133A62);color:white;padding:24px;border-right:1px solid rgba(255,255,255,.12)}.brand .kicker{font-size:13px;letter-spacing:.08em;color:#BDEBE7}.brand h1{font-size:25px;line-height:1.2;margin:8px 0 6px}.brand p{margin:0 0 20px;color:#D5E7F8}.tools{display:grid;gap:10px;margin:18px 0}.tools input{width:100%;border:0;border-radius:14px;padding:12px 14px;font-size:15px}.tools button,.topbar button,.pager button,.primary{border:1px solid var(--line);background:var(--card);color:var(--text);border-radius:12px;padding:9px 12px;cursor:pointer}.toc-part{margin:18px 0}.toc-part h2{font-size:13px;text-transform:uppercase;letter-spacing:.06em;color:#BDEBE7;margin:18px 0 8px}.toc-part a{display:grid;grid-template-columns:auto 1fr auto;gap:8px;align-items:start;text-decoration:none;color:#EAF5FF;padding:10px;border-radius:14px;border:1px solid transparent}.toc-part a:hover,.toc-part a.active{background:rgba(255,255,255,.12);border-color:rgba(255,255,255,.18)}.toc-part a span{font-size:12px;color:#FFDF80}.toc-part a b{font-size:14px;font-weight:600;line-height:1.35}.toc-part a em{font-style:normal;color:#C1D7EB;font-size:12px}
.reader{min-width:0}.topbar{position:sticky;top:0;z-index:10;background:rgba(244,248,252,.9);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);height:64px;display:flex;gap:14px;align-items:center;padding:10px 22px}body.dark .topbar{background:rgba(8,24,39,.88)}#menu{display:none}.progress{flex:1;display:flex;align-items:center;gap:10px;color:var(--muted);font-size:13px}.progress div{height:7px;background:var(--line);border-radius:99px;flex:1;overflow:hidden}.progress b{display:block;height:100%;background:linear-gradient(90deg,var(--teal),var(--blue));width:0}.content{max-width:980px;margin:0 auto;padding:34px 34px 80px}.chapter-hero{background:linear-gradient(135deg,var(--navy),#194D7A);color:white;border-radius:28px;padding:34px;margin-bottom:28px;box-shadow:0 16px 40px rgba(15,42,74,.18)}.chapter-hero .eyebrow{font-size:13px;letter-spacing:.08em;color:#BDEBE7}.chapter-hero h1{font-size:38px;line-height:1.18;margin:10px 0}.chapter-hero .lead{font-size:20px;color:#E8F4FF;margin:0}.meta-row{display:flex;gap:10px;flex-wrap:wrap;margin-top:18px}.meta-row span{background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.2);padding:6px 10px;border-radius:999px;font-size:13px}.content h2{font-size:27px;line-height:1.25;margin:36px 0 12px;color:var(--navy)}body.dark .content h2{color:#B9E6FF}.content h3{font-size:20px;margin:22px 0 6px;color:#153B66}body.dark .content h3{color:#D8ECFF}.content p{font-size:17px;margin:10px 0}.content li{margin:5px 0;font-size:16px}.callout{background:#EAF8FF;border-left:5px solid var(--blue);border-radius:16px;padding:16px 18px;margin:18px 0;color:#173A58}.callout.warning{background:#FFF4E1;border-left-color:#F59E0B;color:#4F2D00}.content .callout.note{background:#EAFBF7;border-left-color:var(--teal)}body.dark .callout{background:#102C46;color:#DDEEFF}body.dark .callout.warning{background:#332405;color:#FFECC2}.checklist{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:18px 24px 18px 36px}.checklist.simple{background:transparent;border:0;padding:0 0 0 24px}.steps{counter-reset:item;background:var(--card);border:1px solid var(--line);border-radius:18px;padding:18px 24px 18px 42px}.steps li p{margin:3px 0 12px;color:var(--muted)}.table-wrap{overflow:auto;margin:18px 0;border:1px solid var(--line);border-radius:18px;background:var(--card)}table{width:100%;border-collapse:collapse}th,td{padding:12px 14px;border-bottom:1px solid var(--line);vertical-align:top;text-align:left}th{background:rgba(43,108,229,.08);color:var(--navy)}body.dark th{color:#D8ECFF}tr:last-child td{border-bottom:0}.prompt-card{background:var(--card);border:1px solid var(--line);border-radius:20px;margin:22px 0;overflow:hidden}.prompt-head{display:flex;justify-content:space-between;align-items:center;background:linear-gradient(90deg,rgba(43,108,229,.13),rgba(18,163,154,.12));padding:12px 16px;font-weight:700}.prompt-card pre{margin:0;padding:18px;white-space:pre-wrap;word-break:break-word;font-family:"SFMono-Regular",Consolas,monospace;font-size:14px;line-height:1.65}.copy-btn{background:white;border:1px solid var(--line);border-radius:10px;padding:5px 9px;cursor:pointer}.source-list{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:18px 24px 18px 38px}.demo-box{background:var(--card);border:1px solid var(--line);border-radius:20px;padding:18px;margin:18px 0}.demo-box textarea{width:100%;border:1px solid var(--line);border-radius:14px;padding:12px;font-size:15px;background:var(--bg);color:var(--text)}.demo-output{margin-top:14px;padding:14px;background:var(--bg);border-radius:14px}.pager{display:flex;justify-content:space-between;max-width:980px;margin:0 auto 50px;padding:0 34px}.pager button:disabled{opacity:.4;cursor:not-allowed}.print-break{border-top:4px solid var(--line);padding-top:24px;margin-top:36px}
@media(max-width:900px){.app{grid-template-columns:1fr}.sidebar{position:fixed;z-index:30;transform:translateX(-105%);transition:.2s;width:min(86vw,360px)}.sidebar.open{transform:translateX(0)}#menu{display:inline-block}.content{padding:22px 18px 70px}.chapter-hero{border-radius:20px;padding:24px}.chapter-hero h1{font-size:28px}.topbar{padding:10px 14px}.progress{display:none}}
@media print{.sidebar,.topbar,.pager{display:none!important}.app{display:block}.content{max-width:100%;padding:0}.chapter-hero{box-shadow:none;break-after:auto}.print-break{break-before:page}.prompt-card,.table-wrap,.callout{break-inside:avoid}body{background:white;color:#111}.content h2{color:#111}}


/* Chapter 23 interactive/API demo additions */
.button-row { display:flex; flex-wrap:wrap; gap:10px; margin:12px 0; }
.button-row button { border:1px solid var(--line); background:var(--panel); color:var(--text); border-radius:10px; padding:10px 14px; cursor:pointer; font-weight:700; }
.button-row button.primary, button.primary { background:#2563eb; border-color:#2563eb; color:#fff; }
.demo-box label { display:block; margin-bottom:8px; }
.demo-box textarea { width:100%; box-sizing:border-box; border:1px solid var(--line); border-radius:12px; padding:12px; background:var(--bg); color:var(--text); font:inherit; line-height:1.6; }
.demo-output { margin-top:12px; padding:14px; border:1px solid var(--line); border-radius:12px; background:var(--panel); overflow:auto; }
.demo-output ul { margin-top:8px; }
.small-note { font-size:.92rem; color:var(--muted); margin:8px 0; }
.audit-table.compact { font-size:.9rem; }
.audit-table.compact td, .audit-table.compact th { vertical-align:top; }
.severity { display:inline-block; border-radius:999px; padding:2px 8px; font-weight:700; border:1px solid var(--line); }
.severity.high { background:#fee2e2; color:#991b1b; }
.severity.medium { background:#fef3c7; color:#92400e; }
.severity.low { background:#dcfce7; color:#166534; }
body.dark .severity.high { background:#451a1a; color:#fecaca; }
body.dark .severity.medium { background:#422006; color:#fde68a; }
body.dark .severity.low { background:#052e16; color:#bbf7d0; }


/* Self-study UI */
.sidebar-head-mobile{display:none}.sidebar-backdrop{position:fixed;inset:0;background:rgba(2,8,23,.48);z-index:25}.icon-btn{border:1px solid rgba(255,255,255,.25);background:rgba(255,255,255,.1);color:white;border-radius:12px;padding:5px 10px;font-size:22px;line-height:1;cursor:pointer}.path-status,.completion-summary{background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.14);border-radius:14px;padding:10px 12px;margin:10px 0;color:#EAF5FF;font-size:13px}.path-status span{color:#BFD7ED}.toc-part a{grid-template-columns:auto auto 1fr auto}.done-dot,.todo-dot{font-style:normal;font-size:13px}.done-dot{color:#8FF0CF}.todo-dot{color:#A6BFDA}.empty-state{color:#DCEBFA;font-size:14px}.path-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:18px 0 26px}.path-card{background:var(--card);border:1px solid var(--line);border-radius:20px;padding:18px;cursor:pointer;transition:.15s box-shadow,.15s transform}.path-card:hover{box-shadow:0 14px 30px rgba(15,42,74,.12);transform:translateY(-2px)}.path-card h3{margin-top:0!important}.path-card button{border:1px solid var(--line);background:var(--navy);color:white;border-radius:12px;padding:9px 12px;cursor:pointer}.chapter-mini-toc{display:flex;flex-wrap:wrap;gap:8px;align-items:center;background:var(--card);border:1px solid var(--line);border-radius:18px;padding:12px 14px;margin:-10px 0 22px}.chapter-mini-toc strong{margin-right:6px;color:var(--navy)}body.dark .chapter-mini-toc strong{color:#D8ECFF}.chapter-mini-toc a{text-decoration:none;border:1px solid var(--line);border-radius:999px;padding:4px 9px;font-size:13px;color:var(--text)}.self-study-note{margin-top:12px}.example-card{background:linear-gradient(135deg,rgba(43,108,229,.07),rgba(18,163,154,.08));border:1px solid var(--line);border-radius:20px;padding:18px;margin:22px 0}.example-card h3{margin-top:0}.example-columns{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.example-columns>div{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:14px}.completion-box{background:var(--card);border:1px solid var(--line);border-radius:22px;padding:20px;margin:34px 0}.completion-box h2{margin-top:0}.topbar button,.pager button,.tools button{font-weight:650}body.sidebar-open{overflow:hidden}.button-row button{background:var(--card)}.button-row button.primary, button.primary,.primary{background:#2563eb!important;border-color:#2563eb!important;color:#fff!important}.demo-output{background:var(--bg)!important}@media(max-width:900px){.sidebar{height:100dvh;padding-top:14px;box-shadow:18px 0 40px rgba(2,8,23,.25)}.sidebar-head-mobile{display:flex;align-items:center;justify-content:space-between;margin-bottom:12px;color:white;font-weight:700}.sidebar.open{transform:translateX(0)}.path-grid{grid-template-columns:1fr}.example-columns{grid-template-columns:1fr}.chapter-mini-toc{position:relative}.topbar{gap:8px}.topbar button{padding:8px 10px}.brand h1{font-size:22px}}@media print{.chapter-mini-toc,.completion-box,.sidebar-backdrop,.path-card button{display:none!important}.path-grid{display:block}.path-card{break-inside:avoid;margin-bottom:12px}.example-columns{grid-template-columns:1fr}}


/* self-study refinements */
.tools select{width:100%;border:1px solid var(--line);background:var(--card);color:var(--text);border-radius:12px;padding:9px 12px}.chapter-badge{border:1px solid var(--line);background:var(--card);border-radius:999px;padding:8px 12px;font-size:13px;color:var(--muted);white-space:nowrap;max-width:280px;overflow:hidden;text-overflow:ellipsis}.completion-summary span{color:#BFD7ED}.topbar{box-shadow:0 4px 18px rgba(15,42,74,.05)}.tools button#resetProgress{border-color:rgba(245,158,11,.45)}.content a{color:#1d4ed8}body.dark .content a{color:#93c5fd}@media(max-width:900px){.chapter-badge{display:none}.tools{gap:8px}.tools button,.tools select{font-size:14px}}@media print{.completion-summary,.path-status,.chapter-badge,.tools select,#resetProgress,#homeBtn,#clearPath{display:none!important}}


/* Taiwan Medical Big Data Research Society branding */
.brand-logo{width:74px;height:74px;object-fit:contain;border-radius:50%;background:#fff;padding:5px;box-shadow:0 8px 24px rgba(0,0,0,.18);margin-bottom:12px;}
.author-line{font-size:13px;color:#F0F7FF;margin:6px 0 12px!important;}
.membership-link{display:inline-flex;align-items:center;justify-content:center;width:100%;text-decoration:none;background:linear-gradient(90deg,#F7D26A,#C99A35);color:#102033!important;border:1px solid rgba(255,255,255,.35);border-radius:14px;padding:10px 12px;font-weight:800;box-shadow:0 8px 20px rgba(0,0,0,.16);}
.membership-link:hover{filter:brightness(1.04);}
.cover-brandline{display:flex;align-items:center;gap:18px;margin-bottom:14px;}
.hero-logo{width:88px;height:88px;object-fit:contain;border-radius:50%;background:#fff;padding:7px;box-shadow:0 10px 26px rgba(0,0,0,.22);flex:0 0 auto;}
.cover-author{font-weight:800;color:#FFFFFF;font-size:16px;margin-top:6px;}
.hero-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px;}
.hero-cta,.hero-secondary{display:inline-flex;align-items:center;justify-content:center;text-decoration:none;border-radius:999px;padding:10px 16px;font-weight:800;}
.hero-cta{background:linear-gradient(90deg,#F8D86D,#B98724);color:#102033!important;border:1px solid rgba(255,255,255,.28);}
.hero-secondary{background:rgba(255,255,255,.13);color:#FFFFFF!important;border:1px solid rgba(255,255,255,.24);}
.brand-callout{background:#FFF8E7;border-left-color:#C4932E;color:#493414;}
body.dark .brand-callout{background:#3B2B09;color:#FFE9A6;}
@media(max-width:900px){.brand-logo{width:62px;height:62px}.cover-brandline{align-items:flex-start;gap:12px}.hero-logo{width:66px;height:66px}.hero-actions{display:grid}.content{font-size:16px;line-height:1.8}.content h2{font-size:22px}.content h3{font-size:18px}.topbar{position:sticky;top:0}.chapter-hero{padding:22px 18px}.meta-row{gap:8px}.meta-row span{font-size:12px}}
@media print{.membership-link,.hero-actions{display:none!important}.brand-logo,.hero-logo{box-shadow:none}}


/* Release candidate footer and social-ready refinements */
.site-footer{max-width:980px;margin:10px auto 38px;padding:18px 34px;color:var(--muted);font-size:13px;line-height:1.7;border-top:1px solid var(--line)}
.site-footer a{color:#1d4ed8;text-decoration:none;font-weight:700}
body.dark .site-footer a{color:#93c5fd}
.full-book-content>.site-footer{padding-left:0;padding-right:0}
@media(max-width:900px){.site-footer{padding:16px 18px 34px;font-size:12.5px}.content p{margin-top:10px}.chapter-hero .lead{font-size:17px}.path-card{padding:16px}.prompt-card pre{font-size:13px}.reader{min-width:0}.table-wrap{margin-left:-4px;margin-right:-4px}}
@media print{.site-footer{display:block!important;color:#111;border-top:1px solid #999;margin-top:28px}.site-footer a{color:#111}}


/* Textbook v1.1 density and structure */
.textbook-hero{background:linear-gradient(135deg,#0B2440,#133D68 58%,#0C5B6F);}
.textbook-opening{background:var(--card);border:1px solid var(--line);border-radius:22px;padding:22px 24px;margin:20px 0 26px;box-shadow:0 8px 22px rgba(15,42,74,.05)}
.textbook-opening p{font-size:18px;line-height:1.9;margin:0 0 14px}.textbook-opening p:last-child{margin-bottom:0}
.concept-card{background:linear-gradient(135deg,rgba(255,255,255,.92),rgba(235,248,255,.9));border:1px solid var(--line);border-radius:24px;padding:22px;margin:26px 0}.dark .concept-card{background:linear-gradient(135deg,#0D2238,#0B2A42)}
.definition-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.definition-list>div{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:16px}.definition-list h3{margin:0 0 6px!important}.definition-list p{margin:0;color:var(--muted)}
.textbook-table caption{text-align:left;font-weight:800;color:var(--navy);padding:12px 14px;background:rgba(18,163,154,.08);border-bottom:1px solid var(--line)}.dark .textbook-table caption{color:#D8ECFF}
.textbook-steps li{padding-bottom:8px}.worked-example{background:linear-gradient(135deg,rgba(43,108,229,.06),rgba(18,163,154,.07));border:1px solid var(--line);border-radius:24px;padding:22px;margin:28px 0}.worked-example h2{margin-top:0}.bad-good{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin:28px 0}.bad-good>div{border:1px solid var(--line);border-radius:20px;padding:18px;background:var(--card)}.bad-good>div:first-child{border-left:6px solid #F59E0B}.bad-good>div:last-child{border-left:6px solid var(--teal)}.bad-good h3{margin-top:0!important}.textbook-deep{background:#F8FBFF;border:1px solid var(--line);border-radius:24px;padding:22px 24px;margin:28px 0}.dark .textbook-deep{background:#0C2035}.textbook-deep p{font-size:17.5px;line-height:1.9}.next-before{border-top:2px solid var(--line);margin-top:32px;padding-top:18px}.next-before p{color:var(--muted)}
.content p{font-size:17.2px}.content h2{letter-spacing:-.01em}.content table td,.content table th{font-size:15.5px;line-height:1.65}
@media(max-width:900px){.definition-list,.bad-good{grid-template-columns:1fr}.textbook-opening{padding:18px}.textbook-opening p{font-size:16.5px}.worked-example,.textbook-deep,.concept-card{padding:18px}.content table td,.content table th{font-size:14px}.bad-good{gap:12px}}
@media print{.textbook-opening,.concept-card,.worked-example,.bad-good>div,.textbook-deep{box-shadow:none;break-inside:avoid}.bad-good{display:block}.bad-good>div{margin-bottom:12px}}


/* v1.2 textbook refinements */
.case-thread,.principle-box,.chapter-synthesis{background:#F8FBFF;border:1px solid var(--line);border-radius:24px;padding:22px 24px;margin:28px 0;box-shadow:0 8px 22px rgba(15,42,74,.04)}
.dark .case-thread,.dark .principle-box,.dark .chapter-synthesis{background:#0C2035}
.case-thread p,.principle-box p,.chapter-synthesis p{line-height:1.9;font-size:17.4px}
.example-card{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:16px 18px;margin:14px 0}
.example-card h3{margin-top:0!important}
.code-block{background:#0B1624;color:#E8F4FF;border-radius:18px;padding:18px;overflow:auto;font-size:13.5px;line-height:1.65}
.full-book-content{max-width:980px;margin:0 auto;padding:34px}
.small-note{font-size:14px;color:var(--muted)}
@media(max-width:900px){.case-thread,.principle-box,.chapter-synthesis{padding:18px}.full-book-content{padding:20px}.content{padding-left:20px;padding-right:20px}.chapter-hero h1{font-size:30px}.content h2{font-size:23px}.content p{font-size:16.4px;line-height:1.78}.meta-row span{font-size:12px}.topbar{padding:8px 12px;gap:8px}.progress{display:none}.chapter-badge{max-width:44vw;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}}


/* v1.4 interactive workbench links */
.tool-workbench-link{margin-top:8px;background:linear-gradient(90deg,#2B6CE5,#12A39A)!important;color:#fff!important;border-color:rgba(255,255,255,.35)!important;}
.sidebar-tool-link{display:flex;align-items:center;justify-content:center;text-decoration:none;border:1px solid rgba(255,255,255,.20);border-radius:12px;padding:9px 12px;color:#fff;background:rgba(255,255,255,.10);font-weight:800;}
.top-tool-link{display:inline-flex;align-items:center;justify-content:center;text-decoration:none;border:1px solid var(--line);border-radius:999px;padding:9px 12px;color:var(--text);background:var(--card);font-weight:750;font-size:14px;white-space:nowrap;}
.interactive-callout{display:flex;align-items:center;justify-content:space-between;gap:22px;background:linear-gradient(135deg,rgba(43,108,229,.12),rgba(18,163,154,.14));border:1px solid var(--line);border-radius:26px;padding:24px;margin:30px 0;box-shadow:0 10px 24px rgba(15,42,74,.06)}
.interactive-callout h2{margin-top:0!important}.interactive-callout p{margin-bottom:0;color:var(--muted)}
@media(max-width:900px){.interactive-callout{display:block;padding:20px}.interactive-callout .hero-cta{margin-top:14px;width:100%;box-sizing:border-box}.top-tool-link{padding:8px 10px;font-size:13px}}
@media print{.top-tool-link,.sidebar-tool-link,.interactive-callout .hero-cta{display:none!important}}