body{background:radial-gradient(ellipse at 80% 4%,#d8aa450b,transparent 33%),var(--bg)}
.edu-skip{position:fixed;left:20px;top:-100px;padding:12px 20px;background:var(--gold2);color:#15110a;z-index:100}.edu-skip:focus{top:12px}
.edu-reading-progress{position:fixed;top:0;left:0;height:2px;background:var(--gold);width:0;z-index:60}
.edu-header{display:flex;align-items:center;justify-content:space-between;gap:30px;padding:31px 0 24px;border-bottom:1px solid #ffffff13}
.edu-identity img{display:block;width:270px;max-width:100%;height:auto}.edu-header nav{display:flex;align-items:center;gap:27px;font-size:11px;color:#bdc1c8}.edu-header nav a:hover{color:var(--gold2)}.edu-login{border:1px solid #d8aa4555;padding:11px 15px;border-radius:3px;color:#ebd296}
.edu-breadcrumb{display:flex;flex-wrap:wrap;gap:13px;font-size:10px;color:#a7aeb8;padding-top:32px}.edu-breadcrumb>span{color:#8f7c4f}.edu-breadcrumb a:hover{color:var(--gold2)}
.edu-hero{display:grid;grid-template-columns:1.3fr .75fr;gap:85px;align-items:center;padding:68px 0 70px}.edu-hero h1{font:400 clamp(52px,5.7vw,83px)/1.04 Georgia,serif;letter-spacing:-.05em;margin:25px 0}.edu-hero h1 em{font-weight:400;color:var(--gold2)}.edu-hero>div>p{font-size:15px;line-height:1.9;color:#b1b6bf;max-width:510px}.edu-hero .eyebrow{font-size:8px;letter-spacing:.15em}.edu-hero .gold-button{margin-top:24px}
.edu-editorial{background:linear-gradient(145deg,#1c1d1e,#0c1117);border:1px solid #d8aa4547;padding:30px 30px 25px;position:relative;transform:rotate(2deg);box-shadow:0 30px 65px #0005}.edu-editorial:before{content:"";inset:8px;position:absolute;border:1px solid #ffffff07;pointer-events:none}.edu-edition{font-size:7px;letter-spacing:.2em;color:#c5b388}.edu-editorial-number{display:block;font:400 130px/1.25 Georgia,serif;letter-spacing:-.09em;color:#efdba8;margin-left:-6px}.edu-editorial>strong{font:400 31px/1.2 Georgia,serif;color:#e6dfd0;display:block;max-width:280px;letter-spacing:-.025em}.edu-editorial-steps{display:flex;align-items:center;gap:9px;font-size:8px;color:#d2bb80;margin-top:34px;padding-bottom:20px;border-bottom:1px solid #ffffff12}.edu-editorial-steps i{height:1px;background:#d8aa4544;flex:1}.edu-editorial>p{font-size:10px;color:#929ba8;line-height:1.8;margin-top:18px}
.edu-principles{display:flex;justify-content:space-between;gap:25px;border-block:1px solid #ffffff17;padding:15px 0}.edu-principles p{font-size:11px;color:#aab1ba}.edu-principles span{color:#c2a45a;font-size:9px;margin-right:12px}
.edu-catalog{padding:68px 0}.edu-catalog-heading{display:flex;align-items:end;justify-content:space-between;gap:30px}.edu-catalog-heading h2{font:400 47px/1.15 Georgia,serif;letter-spacing:-.035em;margin:15px 0 0}.edu-catalog-heading>p{font-size:11px;line-height:1.8;color:#959eab;margin:0}.edu-search{position:relative;margin:35px 0 23px}.edu-search label{display:block;font-size:10px;color:#bfc2c7;margin-bottom:10px}.edu-search input{display:block;width:100%;border:1px solid #31363e;border-radius:4px;background:#10151b;padding:16px 45px 16px 17px;color:#eee6d5;font-size:14px}.edu-search input::placeholder{color:#7f8a98}.edu-search>span{position:absolute;bottom:11px;right:17px;color:#e0c17b;font-size:25px;pointer-events:none}
.edu-filters{display:flex;flex-wrap:wrap;gap:9px}.edu-filters button{font-size:10px;padding:9px 15px;border:1px solid #ffffff21;border-radius:25px;background:transparent;color:#b0b8c2}.edu-filters button[aria-pressed="true"]{background:#d8aa4514;border-color:#d8aa4577;color:#f0d79e}.edu-filters button:hover{border-color:#bca369}.edu-count{font-size:10px;color:#919aa7;margin:25px 0 16px}
.edu-guide-list{display:grid;grid-template-columns:1fr 1fr;gap:0 45px;border-top:1px solid #d8aa4533}.edu-guide{display:grid;grid-template-columns:37px 1fr 22px;gap:20px;padding:30px 0;border-bottom:1px solid #ffffff1a;transition:border-color .2s,background .2s;min-width:0}.edu-guide:hover{border-color:#d8aa4599;background:linear-gradient(90deg,#d8aa4500,#d8aa4505)}.edu-guide-number{font:400 28px/1.2 Georgia,serif;color:#967d40}.edu-category{font-size:8px;text-transform:uppercase;letter-spacing:.16em;color:#b49b5f}.edu-guide h2{font:400 27px/1.2 Georgia,serif;letter-spacing:-.02em;margin:12px 0 13px;color:#eee8dd}.edu-guide p{font-size:12px;line-height:1.85;color:#a3adb9;margin:0 0 18px;max-width:400px}.edu-guide-meta{font-size:8px;color:#979f9e;line-height:1.8;display:block}.edu-guide-meta i{font-style:normal;margin:0 5px;color:#bfa469}.edu-guide-arrow{font-size:22px;color:#bda46a;align-self:center;transition:transform .2s}.edu-guide:hover .edu-guide-arrow{transform:translate(3px,-3px)}.edu-empty{font-size:14px;color:#c4b38c;padding:40px 0}
.edu-purpose{display:flex;align-items:center;gap:28px;padding:35px 0;border-block:1px solid #ffffff16;margin-bottom:30px}.edu-purpose>img{border-radius:50%;object-fit:cover;flex-shrink:0;border:1px solid #d8aa4577}.edu-purpose h2{font:400 30px/1.25 Georgia,serif;margin:12px 0}.edu-purpose p{font-size:12px;line-height:1.8;color:#9ba6b4;margin:0}.edu-purpose .eyebrow{font-size:8px}.edu-purpose .quiet-link{font-size:11px;padding-bottom:0}
.edu-disclosure{font-size:10px;line-height:1.9;color:#99a2ae;margin:25px 0 45px;max-width:1000px}.edu-footer{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:24px;border-top:1px solid #ffffff13;padding:30px 0 45px;font-size:9px;color:#99a2ae}.edu-wordmark{font-size:13px;letter-spacing:.16em;color:#ded3bb}.edu-wordmark>span{font-size:8px;color:#b59854;margin-left:7px}.edu-footer a:hover{color:var(--gold2)}
.lesson-heading{max-width:950px;padding:65px 0 48px}.lesson-heading .eyebrow{font-size:9px}.lesson-heading h1{font:400 clamp(40px,4.8vw,66px)/1.1 Georgia,serif;letter-spacing:-.04em;margin:24px 0}.lesson-heading>p{font-size:17px;line-height:1.8;color:#b6bdc6;max-width:750px}.lesson-byline{display:flex;align-items:center;gap:12px;font-size:11px;color:#d8caa9;margin-top:28px}.lesson-byline img{border-radius:50%;border:1px solid #d8aa4533}.lesson-byline div>span{display:block;font-size:9px;color:#9ea8b5;margin-top:3px}.lesson-byline>a{margin-left:25px;font-size:9px;color:#bba978}
.lesson-layout{display:grid;grid-template-columns:235px minmax(0,780px);gap:70px;align-items:start;padding-top:38px;border-top:1px solid #d8aa4530;margin-bottom:65px}.lesson-toc{position:sticky;top:25px;max-height:calc(100vh - 70px);overflow-y:auto;scrollbar-width:thin}.lesson-toc details>summary{font-size:11px;letter-spacing:.03em;color:#d3bf8e;list-style:none;padding-bottom:20px;pointer-events:none}.lesson-toc summary>span{display:none}.lesson-toc nav{display:grid;gap:7px}.lesson-toc nav a{display:grid;grid-template-columns:19px 1fr;gap:11px;font-size:11px;line-height:1.7;color:#a4aebb;padding:9px 8px 9px 0;border-right:1px solid #ffffff13}.lesson-toc nav a>span{font-size:8px;color:#a18a55;padding-top:3px}.lesson-toc nav a[aria-current]{color:#f0d79e;border-color:var(--gold)}.lesson-toc nav a:hover{color:var(--gold2)}.lesson-all{display:block;font-size:10px;color:#c4af75;margin-top:23px;padding:15px 0;border-top:1px solid #ffffff14}
.lesson-content{min-width:0;font-size:16px;line-height:1.95;color:#bdc5cf}.lesson-content>h2,.lesson-sources h2{font:400 33px/1.25 Georgia,serif;letter-spacing:-.025em;color:#eee5d3;margin:48px 0 21px;scroll-margin-top:35px}.lesson-content>h2:first-child{margin-top:0}.lesson-content p{margin:0 0 20px}.lesson-content strong{color:#e7ddca;font-weight:600}.lesson-content ol,.lesson-content ul{padding-left:24px;margin:20px 0 30px}.lesson-content li{padding-left:6px;margin-bottom:11px}.lesson-content li::marker{color:#c1a05a}.lesson-example{background:linear-gradient(120deg,#d8aa450b,#d8aa4503);border:1px solid #d8aa4535;border-left:2px solid #b79a55;padding:23px 27px;margin:27px 0;color:#dcd0b5;font-size:15px;line-height:1.9}.lesson-example p:last-child{margin:0}.lesson-formula{border:1px solid #ffffff1a;border-radius:4px;background:#11171e;font-size:15px;padding:22px 25px;color:#f0d398;overflow-wrap:anywhere;margin:25px 0;font-variant-numeric:tabular-nums}.lesson-exercise{padding:23px 25px;background:#0f1819;border:1px solid #79c7a02c;border-radius:4px;margin-top:35px;font-size:15px}.lesson-exercise summary{cursor:pointer;color:#bdd3c0;font-size:15px;line-height:1.7}.lesson-exercise[open] summary{margin-bottom:22px}.lesson-exercise p:last-child{margin:0}.lesson-exercise strong{color:#c3dcc9}.lesson-sources{border-top:1px solid #d8aa4533;margin-top:50px;padding-top:10px}.lesson-sources h2{font-size:28px;margin-top:23px}.lesson-sources p,.lesson-sources li{font-size:11px;line-height:1.9}.lesson-sources a{color:#cbb982;text-decoration:underline;text-underline-offset:4px;overflow-wrap:anywhere}.lesson-sources ul{padding-left:20px}.lesson-content .edu-disclosure{font-size:10px}.lesson-navigation{display:grid;grid-template-columns:1fr 1fr;gap:35px;border-top:1px solid #ffffff1a;padding-top:25px;margin-top:38px}.lesson-navigation a>span{display:block;font-size:8px;letter-spacing:.12em;color:#af9457;margin-bottom:14px}.lesson-navigation strong{font:400 24px/1.3 Georgia,serif;color:#e5d6b3;display:block}.lesson-navigation a:hover strong{color:#f0cf7b}
/* Editorial rhythm, accessible visual learning and responsive concept maps. */
.edu-guide-preview{display:block;width:100%;height:auto;aspect-ratio:5/3;object-fit:contain;border:1px solid #d8aa452c;border-radius:5px;margin:20px 0;transition:border-color .25s,box-shadow .25s}
.edu-guide:hover .edu-guide-preview{border-color:#d8aa4560;box-shadow:0 12px 30px #0003}
.edu-guide h2,.lesson-heading h1,.lesson-content h2,.lesson-content h3{text-wrap:balance}
.lesson-content{font-size:18px;line-height:1.95;max-width:72ch;text-wrap:pretty}
.lesson-content>h2{margin-top:56px}
.lesson-byline a,.edu-header nav a,.edu-filters button{min-height:44px;display:inline-flex;align-items:center}
.lesson-overview{border:1px solid #d8aa4538;border-radius:6px;background:linear-gradient(120deg,#d8aa450b,transparent);padding:25px 28px;margin-bottom:38px}
.lesson-overview h2{font:400 29px/1.2 Georgia,serif;color:#ead9b0;margin:0 0 20px;scroll-margin-top:35px}
.lesson-overview ul{list-style:none;margin:0;padding:0;counter-reset:takeaway}
.lesson-overview li{position:relative;margin:0;padding:13px 0 13px 37px;font-size:15px;line-height:1.8;counter-increment:takeaway}
.lesson-overview li+li{border-top:1px solid #ffffff0e}
.lesson-overview li:before{content:"0" counter(takeaway);position:absolute;left:0;top:15px;font-size:10px;color:#c3a668}
.lesson-illustration{margin:35px 0 45px;border:1px solid #d8aa4538;border-radius:6px;overflow:hidden;background:#0b1016}
.illustration-heading{padding:22px 25px 0}.illustration-heading .eyebrow{font-size:8px;color:#c9aa67}
.illustration-heading h3{font:400 27px/1.25 Georgia,serif;color:#e8ddc6;margin:13px 0 8px}
.illustration-scroll{overflow-x:auto;overscroll-behavior-inline:contain;scrollbar-width:thin;scrollbar-color:#b3934c #111822}
.illustration-scroll picture{display:block}.illustration-scroll img{display:block;width:100%;height:auto;min-width:650px;aspect-ratio:5/3}
.lesson-illustration figcaption{padding:18px 25px 22px;border-top:1px solid #ffffff10;font-size:12px;line-height:1.8;color:#adb7c5}
.lesson-illustration figcaption>a{display:inline-flex;align-items:center;min-height:44px;color:#e4c98c;font-size:12px;text-decoration:underline;text-underline-offset:4px}
.illustration-hint{display:none;color:#a4afbd;font-size:11px}
.lesson-mindmap{margin-top:50px;border-block:1px solid #d8aa4530;padding:30px 0 35px;scroll-margin-top:30px}
.mindmap-heading{display:flex;align-items:center;justify-content:space-between;gap:22px}
.mindmap-heading .eyebrow{font-size:8px;color:#c9aa67}
.mindmap-heading h2,.lesson-faq h2,.lesson-related h2{font:400 32px/1.2 Georgia,serif;letter-spacing:-.025em;color:#eee5d3;margin:12px 0 20px;scroll-margin-top:35px}
.mindmap-heading button{border:1px solid #d8aa4550;border-radius:4px;color:#e7c887;background:#d8aa4509;padding:10px 14px;font-size:11px;white-space:nowrap;min-height:44px}
.lesson-mindmap>p{font-size:14px;color:#acb6c4}
.mindmap-root{position:relative;padding:17px 25px;border:1px solid #c9a65c;border-radius:5px;text-align:center;color:#f1d79e;font:400 23px/1.4 Georgia,serif;background:#d8aa450c;max-width:85%;margin:28px auto 32px;text-wrap:balance}
.mindmap-root:after{content:"";position:absolute;bottom:-33px;height:32px;width:1px;background:#b497554d;left:50%}
.mindmap-tree{position:relative;display:grid;grid-template-columns:1fr 1fr;gap:18px;padding-top:20px}
.mindmap-tree:before{content:"";position:absolute;top:0;left:25%;right:25%;height:1px;background:#b497554d}
.mindmap-branch{position:relative;border:1px solid #ffffff18;border-radius:5px;background:#111820;padding:0 20px;min-width:0}
.mindmap-branch:nth-child(-n+2):before{content:"";position:absolute;height:20px;top:-21px;left:50%;width:1px;background:#b497554d}
.mindmap-branch summary{list-style:none;cursor:pointer;display:flex;align-items:center;gap:12px;font-size:14px;font-weight:600;color:#d6c599;min-height:62px;line-height:1.6}
.mindmap-branch summary::-webkit-details-marker{display:none}.mindmap-branch summary:after{content:"+";margin-left:auto;color:#c6ab6c;font-size:20px;font-weight:400}.mindmap-branch[open] summary:after{content:"−"}
.mindmap-branch summary>span{font:400 20px Georgia,serif;color:#9e8956}
.mindmap-branch ul{border-top:1px solid #ffffff0c;margin:0;padding:13px 0 14px 18px;list-style:none}
.mindmap-branch li{position:relative;font-size:13px;line-height:1.8;margin:0;padding:6px 0;color:#b4c0cc}
.mindmap-branch li:before{content:"";position:absolute;left:-17px;top:18px;width:6px;height:1px;background:#79c7a080}
.lesson-faq{margin:36px 0}.lesson-faq h2{font-size:30px;margin-bottom:24px}
.lesson-faq details{border-top:1px solid #ffffff1b;padding:0 2px}.lesson-faq details:last-child{border-bottom:1px solid #ffffff1b}
.lesson-faq summary{font-size:15px;line-height:1.75;color:#ded5c1;cursor:pointer;padding:21px 20px 21px 0}
.lesson-faq details p{font-size:15px;line-height:1.9;color:#aebbc9;margin-bottom:23px}
.lesson-author{display:flex;gap:19px;align-items:start;padding:25px 0;border-block:1px solid #ffffff16;margin:38px 0}
.lesson-author img{border-radius:50%;flex-shrink:0;border:1px solid #d8aa4540}
.lesson-author strong{font-size:14px}.lesson-author p{font-size:12px;line-height:1.85;margin:8px 0}.lesson-author a{color:#e4c98c;font-size:12px;display:inline-flex;align-items:center;min-height:44px}
.lesson-related{margin:35px 0}.lesson-related .eyebrow{font-size:8px}.lesson-related h2{font-size:28px}
.lesson-related>a{display:flex;align-items:center;justify-content:space-between;gap:20px;font-size:15px;line-height:1.6;color:#d7c292;padding:18px 0;border-top:1px solid #ffffff15;transition:color .2s}
.lesson-related>a:last-child{border-bottom:1px solid #ffffff15}.lesson-related>a:hover{color:#f0cf7b}
.lesson-sources p,.lesson-sources li{font-size:13px}.lesson-content .edu-disclosure{font-size:12px}
@media(min-width:1600px){.lesson-layout{gap:100px}}
@media(max-width:1120px){.edu-hero{gap:40px}.edu-editorial{padding:25px}.edu-hero h1{font-size:65px}.edu-guide-list{gap:0 25px}.edu-guide{gap:14px;grid-template-columns:30px 1fr 18px}.edu-guide h2{font-size:25px}.lesson-layout{grid-template-columns:200px minmax(0,1fr);gap:40px}.lesson-toc nav a{font-size:10px}}
@media(max-width:850px){.edu-hero{grid-template-columns:1fr .65fr;gap:35px;padding-top:50px}.edu-hero h1{font-size:53px}.edu-hero>div>p{font-size:13px}.edu-hero .eyebrow{font-size:7px;letter-spacing:.1em}.edu-editorial{padding:25px 20px}.edu-editorial-number{font-size:105px}.edu-editorial>strong{font-size:26px}.edu-editorial-steps{font-size:6px;gap:5px}.edu-edition{font-size:6px}.edu-principles{gap:15px}.edu-principles p{font-size:9px}.edu-principles span{display:block;margin-bottom:7px}.edu-guide-list{grid-template-columns:1fr}.edu-guide{grid-template-columns:45px 1fr 25px;gap:22px}.edu-guide h2{font-size:29px}.edu-guide p{max-width:100%;font-size:13px}.edu-guide-meta{font-size:9px}.lesson-layout{grid-template-columns:1fr;gap:25px;padding-top:25px}.lesson-toc{position:static;max-height:none;border-bottom:1px solid #ffffff15;padding-bottom:20px}.lesson-toc details>summary{pointer-events:auto;display:flex;justify-content:space-between;padding:0;font-size:13px}.lesson-toc summary>span{display:inline}.lesson-toc details[open]>summary{padding-bottom:18px}.lesson-toc nav{grid-template-columns:1fr 1fr;gap:5px 25px}.lesson-toc nav a{font-size:11px}.lesson-all{display:none}.lesson-heading{padding-top:45px;padding-bottom:32px}.lesson-heading h1{font-size:53px}.lesson-content{max-width:760px}.edu-identity img{width:235px}.edu-header nav{gap:18px;font-size:10px}.edu-purpose h2{font-size:27px}}
@media(max-width:600px){.edu-header{padding-top:24px;gap:15px}.edu-identity img{width:200px}.edu-header nav>a:not(.edu-login){display:none}.edu-login{font-size:9px;padding:10px}.edu-breadcrumb{font-size:9px;gap:10px;padding-top:25px}.edu-hero{grid-template-columns:1fr;gap:35px;padding:40px 0}.edu-hero h1{font-size:60px}.edu-hero>div>p{font-size:14px}.edu-hero .gold-button{font-size:12px}.edu-editorial{transform:none;display:grid;grid-template-columns:90px 1fr;gap:0 20px;padding:22px}.edu-edition{grid-column:1/-1;font-size:7px}.edu-editorial-number{grid-row:2/4;font-size:90px;align-self:center}.edu-editorial>strong{font-size:27px;margin-top:18px}.edu-editorial-steps{grid-column:1/-1;font-size:8px;margin-top:23px}.edu-editorial>p{grid-column:2;margin-top:12px;font-size:10px}.edu-principles{padding:8px 0;gap:14px}.edu-principles p{font-size:9px;line-height:1.8}.edu-catalog{padding:45px 0}.edu-catalog-heading{display:block}.edu-catalog-heading h2{font-size:39px}.edu-catalog-heading>p{margin-top:17px;font-size:11px}.edu-search input{font-size:12px;padding-block:15px}.edu-filters{gap:7px}.edu-filters button{padding:8px 12px;font-size:9px}.edu-guide{grid-template-columns:28px 1fr 18px;gap:14px;padding:25px 0}.edu-guide h2{font-size:26px}.edu-guide p{font-size:12px}.edu-guide-number{font-size:24px}.edu-guide-meta{font-size:8px}.edu-purpose{align-items:start;gap:18px;padding-block:27px}.edu-purpose>img{width:54px;height:54px}.edu-purpose h2{font-size:26px}.edu-purpose .eyebrow{font-size:6px}.edu-purpose p{font-size:11px}.edu-disclosure{font-size:9px}.edu-footer{font-size:9px;gap:20px}.edu-footer>span{display:none}.lesson-heading h1{font-size:42px}.lesson-heading>p{font-size:15px}.lesson-byline{gap:10px;flex-wrap:wrap}.lesson-byline>a{margin-left:0;display:block;width:100%;margin-top:8px}.lesson-toc nav{grid-template-columns:1fr}.lesson-content{font-size:16px;line-height:1.9}.lesson-content>h2{font-size:29px;margin-top:38px}.lesson-example{padding:19px 18px;font-size:14px}.lesson-formula{font-size:13px;padding:18px}.lesson-exercise{padding:20px 18px;font-size:14px}.lesson-exercise summary{font-size:14px}.lesson-navigation{grid-template-columns:1fr;gap:25px}.lesson-navigation a:last-child{border-top:1px solid #ffffff12;padding-top:24px}.lesson-navigation strong{font-size:25px}.lesson-sources h2{font-size:26px}}

@media(max-width:850px){.lesson-content{font-size:17px;max-width:72ch}.lesson-toc nav a{min-height:44px}.lesson-mindmap{margin-top:38px}}
@media(max-width:650px){.illustration-hint{display:block}.mindmap-heading{align-items:start;flex-direction:column;gap:0;margin-bottom:18px}.mindmap-heading h2{margin-bottom:14px}.mindmap-tree{grid-template-columns:1fr;padding-top:0;gap:14px}.mindmap-tree:before,.mindmap-branch:nth-child(-n+2):before{display:none}.mindmap-root{max-width:100%;font-size:22px;margin-bottom:24px}.mindmap-root:after{height:24px;bottom:-25px}.mindmap-branch{padding-inline:18px}.mindmap-branch summary{min-height:62px}.mindmap-branch ul{display:grid;grid-template-columns:1fr;gap:0}.lesson-overview{padding:22px 19px}.lesson-overview li{font-size:14px}.illustration-heading{padding-inline:18px}.illustration-heading h3{font-size:25px}.lesson-illustration figcaption{padding:15px 18px 18px}.lesson-author{gap:15px}.lesson-author img{width:48px;height:48px}.lesson-faq h2{font-size:28px}.edu-guide-preview{margin:17px 0}.lesson-related>a{font-size:14px}}
@media(prefers-reduced-motion:reduce){.edu-guide-preview,.edu-guide,.edu-guide-arrow{transition:none}}