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.worked-example .example-label{font-size:11px;font-weight:800;letter-spacing:.12em;color:#147769}
.worked-example h3{font-size:21px;line-height:1.3;margin:6px 0 10px}
.worked-example p{font-size:14px;line-height:1.75;margin:0;color:#415c61}
.worked-example details{background:#fff;border-color:#d0e1db}
.worked-example details p{margin-top:10px}
.dark-band .worked-example{background:#10283a;border-color:#2a5061}
.dark-band .worked-example .example-label{color:var(--cyan)}
.dark-band .worked-example p{color:#adbdc4}
.dark-band .worked-example details{background:#0b1c2b;border-color:#315064}
.dark-band .worked-example details summary{color:var(--ink)}
@media(max-width:780px){.worked-example{grid-template-columns:1fr;padding:18px}}

.applications{background:#f6f9f6}
.topbar-actions{display:flex;align-items:center;gap:22px}
.case-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}
.case-card{display:flex;flex-direction:column;background:#fff;border:1px solid #d8e5e0;border-radius:17px;padding:26px;box-shadow:0 12px 35px rgba(14,54,52,.04)}
.case-card>span{font-size:11px;font-weight:800;letter-spacing:.1em;color:#167c71}
.case-card h3{font-size:25px;line-height:1.25;margin:9px 0 12px}
.case-card p,.case-card li{font-size:14px;line-height:1.75;color:#526b72}
.case-card p{margin:0 0 14px}
.case-card ol{padding-left:20px;margin:5px 0 18px}
.case-card li+li{margin-top:8px}
.case-card .case-result{margin-top:auto;padding:13px;background:#e7f4ee;border-radius:10px;color:#28685e;font-weight:650}
.pitfalls{margin-top:28px;padding:27px;background:#e9f1ed;border-radius:18px}
.pitfalls h3{font-size:25px;margin:0 0 18px}
.pitfall-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}
.pitfall-grid>div{background:#fff;border:1px solid #d8e5e0;border-radius:11px;padding:17px}
.pitfall-grid strong{font-size:15px;color:#173947}
.pitfall-grid p{font-size:13px;color:#526b72;line-height:1.7;margin:8px 0 0}
@media(max-width:1120px){.case-grid{grid-template-columns:1fr}.pitfall-grid{grid-template-columns:1fr 1fr}}
@media(max-width:780px){.pitfalls{padding:18px}.pitfall-grid{grid-template-columns:1fr}}

/* A quieter, editorial reading surface. Keep the graphs as distinct instruments. */
:root{
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  --muted:#59685e;--cyan:#22695e;--amber:#89502f;--line:#d4d7cc;
  --paper:#f6f3eb;--paper-ink:#24352f;--paper-muted:#5f6d65;
  --radius:5px;--sidebar:248px
}
body{font-family:"Segoe UI","Noto Sans SC","Microsoft YaHei",system-ui,sans-serif;line-height:1.8}
h1,h2,h3,.brand strong,.roadmap-grid strong{font-family:Georgia,"Noto Serif SC","Songti SC",serif;font-weight:600}
h1{font-size:clamp(44px,5vw,72px);line-height:1.18;letter-spacing:-.04em}
h1 em{color:var(--cyan)}
:focus-visible{outline-color:var(--amber)}
.skip-link{background:var(--cyan);color:#fff;border-radius:3px}
.sidebar{background:#eeeae1;color:var(--paper-ink);padding:31px 19px;border-color:var(--line);overflow-y:auto}
.brand{gap:11px}.brand-mark{width:38px;height:38px;border-radius:2px;background:transparent;border:1.5px solid var(--cyan);color:var(--cyan);font-family:Georgia,serif;font-size:25px}
.brand strong{font-size:18px;letter-spacing:.01em}.brand small{color:#79827a;font-size:10px;letter-spacing:.16em}
.progress-wrap{margin:45px 0 26px}.progress-line{color:#69756b}.progress-line strong{color:var(--paper-ink)}
.progress-track{height:3px;background:#d3d8cd}.progress-track span{background:var(--cyan)}
.sidebar nav{gap:0;border-top:1px solid var(--line)}
.sidebar nav a{border-bottom:1px solid var(--line);border-radius:0;color:#506058;font-size:13px;padding:12px 8px;transition:background .15s,color .15s}
.sidebar nav a span{color:#8c968a;font-size:11px}.sidebar nav a:hover,.sidebar nav a.active{background:#e1e8dc;color:#1d5f55}
.sidebar nav a.active{box-shadow:inset 3px 0 var(--cyan)}.sidebar nav a.done span{color:var(--cyan)}
.ghost-btn{border:0;border-top:1px solid var(--line);border-radius:0;color:#66736a;text-align:left;padding:16px 8px 0}
.ghost-btn:hover{color:var(--cyan);border-color:var(--line)}
main{max-width:1680px}
.topbar{background:rgba(246,243,235,.96);color:var(--paper-ink);border-bottom:1px solid var(--line);backdrop-filter:none;padding:0 clamp(24px,5vw,82px)}
.topbar-title{color:#778178;font-size:12px;letter-spacing:.08em}.top-link{color:#405b52;font-size:13px}.top-link:hover{text-decoration:underline;text-underline-offset:5px}
.menu-btn{color:var(--paper-ink);border-color:var(--line);border-radius:3px}
.hero{background:#f6f3eb;color:var(--paper-ink);min-height:680px;padding:82px clamp(24px,5vw,82px) 90px;grid-template-columns:minmax(280px,.9fr) minmax(440px,1.1fr);gap:clamp(35px,5vw,88px)}
.hero:after{display:none}.hero .eyebrow,.dark-band .eyebrow{color:var(--amber)}
.eyebrow{color:var(--amber);font-size:11px;letter-spacing:.16em;margin-bottom:18px}
.eyebrow:before{content:"";display:inline-block;width:22px;height:1px;background:currentColor;vertical-align:middle;margin-right:10px}
.hero-lead{color:#53645d;font-size:17px;line-height:1.9}.hero-actions{margin:36px 0 48px}
.primary-btn{background:var(--cyan);color:white;border-radius:3px;font-size:14px;padding:11px 19px;font-weight:650}
.primary-btn:hover,.complete-btn:hover{background:#174d45}.text-btn{color:#52655b;font-size:14px}
.promise-grid{border-color:var(--line);gap:32px}.promise-grid strong{font-family:Georgia,serif;color:#263f38;font-size:24px;font-weight:600}.promise-grid span{color:#6b786e}
.card{background:var(--panel);border:1px solid #c9d2c8;border-radius:var(--radius);box-shadow:none}
.hero-lab{padding:18px}.card-head{color:#46594f;font-size:12px;font-weight:650;letter-spacing:.03em;margin-bottom:13px}
.live-dot{width:6px;height:6px;background:var(--amber);box-shadow:none;margin-right:9px}
.icon-btn{border:1px solid #cbd5ca;background:transparent;color:#315c51;border-radius:3px;font-size:12px}
.icon-btn:hover{background:#e8eee5}.hero canvas,.mini-lab canvas{background:#1b3031;border-radius:2px}
.control-grid label,.range-label{color:#5c6c61;font-size:12px}.control-grid output,.range-label output{color:#244f45}
input[type=range]{accent-color:var(--cyan)}.lab-note{color:#697a70}.cyan{color:var(--cyan)}.amber{color:var(--amber)}
.section{padding:90px clamp(24px,5vw,82px)}
.section-title{margin-bottom:36px}.section-title h2,.lesson h2{font-size:clamp(32px,3.6vw,49px);line-height:1.25;letter-spacing:-.025em}
.section-title>p{color:var(--paper-muted)}
.roadmap{background:#ebece5}.roadmap-grid{gap:20px}
.roadmap-grid article{background:transparent;border:0;border-top:2px solid #b8c9bb;border-radius:0;padding:17px 5px 0;min-height:195px}
.roadmap-grid span{color:#6d5d40;font-size:11px}.roadmap-grid strong{color:#294f46;font-size:36px;margin:5px 0}
.roadmap-grid p{color:#606f65}
.lesson{border-top:1px solid var(--line)}.lesson-kicker{margin-bottom:33px;color:#617269}
.lesson-kicker>span{width:auto;height:auto;display:block;border:0;border-radius:0;color:var(--amber);font-family:Georgia,serif;font-size:30px;font-weight:500;line-height:1}
.lesson-kicker div{font-size:13px}.lesson-kicker small{color:#859087}
.lesson-copy .lead{color:var(--paper-muted);font-size:17px;line-height:1.85}
.concept-stack{border-color:var(--line)}.concept-stack>div{border-color:var(--line)}.concept-stack p{color:var(--paper-muted)}.term{color:var(--cyan)}
.formula{background:#ebece3;border-left:2px solid var(--amber);border-radius:0;color:#2b443b}.formula.featured{border-bottom:2px solid var(--amber)}
.formula.multiline small{color:#67776a}
details{border-color:var(--line);border-radius:3px;color:var(--paper-muted)}details summary{color:var(--paper-ink)}
.mini-lab{color:var(--paper-ink);padding:18px}.insight{background:#e8eee7;color:#435b50;border-radius:3px}
.checkpoint{border-color:var(--line);margin-top:48px}.checkpoint p{color:var(--paper-muted)}
.choice-row button,.reader-answer button{border-color:#bfcbc0;background:transparent;border-radius:3px;color:#31584e}
.choice-row button:hover,.reader-answer button:hover{background:#e7eee6}
.choice-row button.correct{background:#d9ebdd;border-color:#7aaa89}.choice-row button.wrong{background:#f3e2d9;border-color:#c99478}
.complete-btn{background:var(--cyan);border-radius:3px;font-weight:650;font-size:13px}.complete-btn.done{background:#d8e9dc;color:#2c6752}
.dark-band{background:var(--bg2);color:var(--paper-ink)}
.dark-band .lesson-kicker,.dark-band .lesson-copy .lead,.dark-band .section-title>p,.dark-band .muted{color:var(--paper-muted)}
.dark-band .lesson-kicker>span{border:0}.dark-band .formula{background:#e0e6dc;color:#29453d}
.dark-band details,.dark-band .checkpoint{border-color:#cbd2c6}
.quadrant-table th,.quadrant-table td{border-color:#cbd2c6}.quadrant-table th{color:#687970}
.callout,.dark-band .callout{background:#e2ebe0;border-radius:3px;border-left:2px solid #7ca58a}
.callout p,.dark-band .callout p{color:#4e6659}
.callout.warn,.dark-band .callout.warn{background:#f0e8db;border-left-color:#b9875b}
.callout.warn p,.dark-band .callout.warn p{color:#765e47}
.value-pills span{background:#e8eee7;color:#53685b;border-radius:3px}.value-pills strong{color:var(--cyan)}
.reasoning-list li,.dark-band .reasoning-list li{border-color:var(--line)}
.reasoning-list strong,.dark-band .reasoning-list strong{color:var(--cyan)}
.reasoning-list span,.dark-band .reasoning-list span{color:var(--paper-muted)}
.formula-pair>div{border-color:#cad2c8;border-radius:3px}.formula-pair>div>span{color:var(--cyan)}.formula-pair p{color:var(--paper-muted)}
.translation{background:#e5e8dc;border-left-color:var(--amber)}.translation p{color:#52665a}
.duality-grid>div{background:transparent;border:0;border-top:1px solid #bdcabe;border-radius:0;padding:17px 4px;min-height:145px}
.duality-grid span{color:var(--cyan)}.duality-grid p{color:var(--paper-muted)}
.compare-table>div{border-color:var(--line);border-radius:3px}.compare-table strong{color:var(--cyan)}
.metric-grid div{background:#e6eae1;border-radius:3px}.metric-grid span{color:#67776d}
.spectrum-bars{border-color:#aebcaf;background:repeating-linear-gradient(to right,transparent 0,transparent calc(25% - 1px),#e0e6dc 25%)}
.spectrum-bars i{background:var(--amber);box-shadow:none}.axis{color:#6d796f}
.reader-answer{background:#e9eee6;border-radius:3px}.reader-answer button{background:transparent;color:var(--cyan);border-color:#aabeb0}.reader-answer div{color:#53665b}
.window-card{border-color:var(--line);border-radius:3px;background:transparent}.window-card.active{border-color:#83aa8d;background:#e5eee4}
.window-card strong{color:#294a40}.window-card span{color:var(--paper-muted)}.window-card small{color:#718075}
.master-grid article{background:transparent;border:0;border-top:2px solid #b8c9bb;border-radius:0;padding:20px 6px}
.master-grid article>span{color:var(--amber)}.master-grid p,.master-grid li{color:var(--paper-muted)}
.final-challenge{border:1px solid #c5d3c4;border-radius:3px;background:#e2e9de}
.final-challenge p{color:var(--paper-muted)}.challenge-checks label{background:transparent;border-bottom:1px solid #c5d3c4;border-radius:0;color:#435d50}
.challenge-checks input{accent-color:var(--cyan)}
.worked-example,.dark-band .worked-example{background:#e8ede3;border:0;border-left:2px solid #86a895;border-radius:0;padding:22px 26px}
.worked-example .example-label,.dark-band .worked-example .example-label{color:var(--amber)}
.worked-example p,.dark-band .worked-example p{color:#4e6557}
.worked-example details,.dark-band .worked-example details{background:#f8f8f2;border-color:#d0d9ce}
.dark-band .worked-example details summary{color:var(--paper-ink)}
.applications{background:#f6f3eb}.case-grid{gap:25px}
.case-card{background:transparent;border:0;border-top:2px solid #b4c7b5;border-radius:0;box-shadow:none;padding:20px 4px}
.case-card>span{color:var(--amber)}.case-card h3{font-size:26px}.case-card p,.case-card li{color:var(--paper-muted)}
.case-card .case-result{background:#e7ece2;border-radius:0;color:#3d624d;border-left:2px solid #8eaa8d}
.pitfalls{background:#e9ece3;border-radius:3px}.pitfall-grid>div{background:transparent;border:0;border-top:1px solid #c7d0c2;border-radius:0;padding:17px 3px}
.pitfall-grid strong{color:var(--paper-ink)}.pitfall-grid p{color:var(--paper-muted)}
.cheatsheet{background:#ebeee5}.sheet-grid>div{background:transparent;border:0;border-top:1px solid #bfcdbd;border-radius:0;padding:17px 4px}
.sheet-grid span{color:var(--amber)}.sheet-grid code{color:#2b473d}.sheet-grid p{color:var(--paper-muted)}
footer{background:#e4e8de;color:var(--paper-ink);border-top:1px solid var(--line);padding:45px clamp(24px,5vw,82px)}
footer p{color:var(--paper-muted)}footer a{color:var(--cyan)}
@media(max-width:1300px){
  .hero,.lesson-grid,.single-focus{grid-template-columns:1fr}
  .hero{min-height:0}.hero-lab,.mini-lab{max-width:800px;width:100%}
  .roadmap-grid,.master-grid,.sheet-grid{grid-template-columns:1fr 1fr}
  .case-grid{grid-template-columns:1fr}
}
@media(max-width:1120px){.hero{grid-template-columns:1fr;min-height:0}.hero-lab{max-width:800px}.roadmap-grid,.master-grid,.sheet-grid{grid-template-columns:1fr 1fr}}
@media(max-width:780px){
  .sidebar{box-shadow:10px 0 30px rgba(32,54,44,.12)}
  .hero{padding:52px 20px 65px}.section{padding:68px 20px}
  .roadmap-grid,.master-grid,.sheet-grid{grid-template-columns:1fr}
  .roadmap-grid article{min-height:0}.worked-example{padding:19px}
  .topbar-actions{gap:15px}.top-link{font-size:12px}
  h1{font-size:clamp(37px,10vw,47px)}
}

.roadmap-hint{border-top:1px solid #bdcbbd;margin:35px 0 0;padding-top:20px;max-width:900px;color:#52665a;font-size:15px;line-height:1.9}
.roadmap-hint strong{color:#294b3e}
.bridge-note{font-size:14px;line-height:1.85;color:#4e6458;border-left:2px solid #aac0a9;padding:2px 0 2px 14px;margin:0 0 19px}
.lesson-depth{display:grid;grid-template-columns:minmax(0,1.35fr) minmax(270px,.65fr);gap:clamp(28px,5vw,75px);border-top:1px solid var(--line);margin-top:46px;padding-top:32px}
.lesson-depth .depth-label{font-size:11px;font-weight:800;letter-spacing:.12em;color:var(--amber)}
.lesson-depth h3{font-size:clamp(22px,2.3vw,29px);line-height:1.35;margin:8px 0 16px}
.lesson-depth p{font-size:15px;line-height:1.95;color:#4d6156;margin:0 0 14px;max-width:74ch}
.lesson-depth .depth-steps{background:#e9eee5;border-left:2px solid #8eaa8d;padding:21px 24px;align-self:start}
.depth-steps>strong{font-size:13px;color:#335b45}
.depth-steps ol{padding-left:20px;margin:13px 0 0}
.depth-steps li{font-size:14px;line-height:1.75;color:#4d6253}
.depth-steps li+li{margin-top:11px}
.dark-band .lesson-depth{border-color:#cbd2c6}
.dark-band .lesson-depth p{color:#4d6156}
.dark-band .depth-steps{background:#e0e8dd}
.challenge-checks label{display:flex;align-items:flex-start;gap:11px;padding:10px 4px 12px}
.challenge-checks input{flex:none;margin:5px 0 0}
.challenge-checks label strong,.challenge-checks label small{display:block}
.challenge-checks label strong{font-size:13px;color:#294b3c;font-weight:650}
.challenge-checks label small{font-size:12px;color:#5f7164;line-height:1.55;margin-top:3px}
.notation-guide{border-top:2px solid #b8c9bb;border-bottom:1px solid #b8c9bb;padding:24px 0 30px;margin-bottom:25px}
.notation-guide h3{font-size:26px;margin:0 0 8px}.notation-guide>div>p{font-size:14px;color:#52665a;line-height:1.85;max-width:920px;margin:0 0 21px}
.notation-guide dl{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px 26px;margin:0}
.notation-guide dl>div{border-top:1px solid #c9d4c7;padding-top:10px}
.notation-guide dt{font-family:Georgia,serif;font-weight:700;font-size:18px;color:#31594a}
.notation-guide dd{font-size:13px;color:#566a5d;line-height:1.75;margin:5px 0 0}
@media(max-width:1100px){.lesson-depth{grid-template-columns:1fr}.notation-guide dl{grid-template-columns:1fr 1fr}}
@media(max-width:780px){.lesson-depth{margin-top:34px;padding-top:25px}.lesson-depth .depth-steps{padding:18px}.notation-guide dl{grid-template-columns:1fr}}