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/* Shared interior rhythm: a purposeful introduction, a concrete surface, quieter reading. */
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/* Systems: choose a stage without simulating a live publishing action. */
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/* Company: identity, work, and a verifiable point of contact. */
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.company-principles a{position:relative;display:block;padding:26px 25px 0 0;border-top:1px solid #676767}
.company-principles h3{font-size:25px;line-height:1.3}
.company-principles p{font-size:15px;color:#afafaf;line-height:1.8;margin-top:20px}
.company-principles a>span{position:absolute;right:0;top:29px;color:#d0d0d0}
.interior-page .company-details{background:#cacaca;color:#373737;max-width:none;padding-block:55px 65px}
.interior-page .company-details dl>div{border-color:#a2a2a2}
.interior-page .company-details dt{color:#636363}
.interior-page .company-details a:focus-visible{outline-color:#444444}
.interior-page .principles-opening{padding-block:60px 65px;background:linear-gradient(#080808,#171717)}
.interior-page .principles-opening h1{font-size:clamp(49px,6vw,86px);line-height:1.1;margin-top:35px}
.interior-page .principles-prose article{border-color:#464646;gap:10%}
.interior-page .principles-prose p{color:#b9b9b9;line-height:1.95}
.interior-page .principles-return{background:#cecece;color:#383838;border-color:#a2a2a2}
.interior-page .principles-return a{color:#4a4a4a;border-color:#848484}
/* Q&A: local search and topic filtering; every answer remains in the page. */
.question-directory{padding-top:0;padding-bottom:65px}
.question-search{max-width:810px;margin:0 0 45px auto}
.question-search>label{display:block;font-size:14px;color:#b9b9b9;margin-bottom:14px}
.question-search>div{display:flex;align-items:center;border-bottom:1px solid #7b7b7b;background:#1b1b1b;padding:15px 20px;gap:20px}
.question-search input{width:100%;min-width:0;border:0;background:none;outline:0;padding:6px 0;font-size:19px;line-height:1.5;color:#eaeaea;font-family:inherit}
.question-search input::placeholder{color:#969696}
.question-search>div:focus-within{outline:2px solid #bebebe;outline-offset:4px}
.question-search button{border:0;background:none;padding:8px;color:#cdcdcd;font-size:13px}
.question-search>p{font-size:12px;color:#a1a1a1;line-height:1.5;margin-top:13px}
.question-directory-layout{display:grid;grid-template-columns:230px minmax(0,1fr);gap:70px}
.question-categories{display:flex;flex-direction:column;position:sticky;top:35px;align-self:start;border-top:1px solid #535353}
.question-categories button{display:flex;align-items:center;justify-content:space-between;gap:20px;text-align:left;border:0;border-bottom:1px solid #3d3d3d;background:none;padding:17px 10px;color:#a5a5a5;font-size:14px;line-height:1.5}
.question-categories button[aria-pressed=true]{background:#2a2a2a;color:#e8e8e8;border-left:2px solid #b6b6b6;padding-left:8px}
.question-categories button>span{font-size:11px;color:#9e9e9e}
.question-group{scroll-margin-top:35px;margin-bottom:50px}
.question-group:last-child{margin-bottom:0}
.question-group h2{font-size:31px;line-height:1.2;letter-spacing:-.04em;margin-bottom:24px}
.question-group .audience-faq .chapter-link{font-size:13px;margin-top:19px}
.question-empty{padding:25px 0 60px}
.question-empty h2{font-size:32px;line-height:1.2}
.question-empty p{font-size:16px;color:#b3b3b3;margin-top:20px}
.question-empty button{background:#cfcfcf;color:#353535;padding:13px 20px;border:0;margin-top:25px;font-size:14px}
/* Existing interactive and purchase surfaces keep their behavior, with the same hierarchy. */
.interior-page .subhero{padding-block:65px}
.interior-page .subhero h1{font-size:clamp(49px,6.2vw,87px);line-height:1.1}
.interior-page .subhero>p:not(.eyebrow){color:#b2b2b2;font-size:18px;max-width:720px}
.interior-page .exercise{background:#d1d1d1;padding-block:55px;color:#333333}
.interior-page .exercise-top{gap:45px}
.interior-page .exercise h2{font-size:47px;line-height:1.14}
.interior-page .exercise-top>p{font-size:15px;color:#676767}
.interior-page .question-meta{border-color:#9b9b9b;color:#5c5c5c}
.interior-page .passage>p:not(.source-note){font-size:18px;line-height:1.95;color:#454545}
.interior-page .answer-option{background:#dcdcdc;border-color:#aaaaaa;font-size:15px;line-height:1.7;padding:17px}
.interior-page .answer-option:has(input:checked){background:#c5c5c5;border-color:#717171}
.interior-page .answer-option[data-correct=true]{background:#c8c8c8;border-color:#727272}
.interior-page .answer-option[data-wrong=true]{background:#d4d4d4;border-color:#7d7d7d}
.interior-page .feedback{border-color:#919191}
.interior-page .classroom{padding-top:25px}
.interior-page .class-workspace{background:#d5d5d5;border-radius:0}
.interior-page .learner-detail{background:#c5c5c5}
.interior-page .learner-row[aria-pressed=true]{background:#c0c0c0}
.interior-page .class-list .fine-print{font-size:12px!important}
.interior-page .academy-contact{background:#cccccc;color:#393939}
.interior-page .academy-contact>p:not(.eyebrow){color:#616161}
.interior-page .academy-contact .button{background:#434343;color:#f3f3f3}
.interior-page .academy-contact .text-link{color:#424242;border-color:#7e7e7e}
.interior-page .pricing-section{padding-top:0}
.interior-page .pricing-tabs button[aria-pressed=true]{color:#d7d7d7;border-color:#cbcbcb}
.interior-page .offer-row{border-color:#4b4b4b;padding-block:25px}
.interior-page .offer-row:hover{background:#252525}
.interior-page .offer-row small,.interior-page .offer-row>span:nth-child(2){color:#aeaeae}
.interior-page .purchase-notice{background:#242424;border-color:#6a6a6a}
.interior-page .academy-pricing{background:#cacaca;color:#3b3b3b}
.interior-page .academy-pricing .section-intro>p,.interior-page .academy-price-grid p{color:#616161}
.interior-page .academy-price-grid article>span{color:#5b5b5b}
.interior-page .academy-pricing .outline{color:#3c3c3c;border-color:#838383}
.interior-page .plan-dialog{background:#d7d7d7;color:#3b3b3b}
.interior-page .plan-dialog .dark{background:#424242;color:white}
.interior-page .seller dd{color:#c3c3c3}
.interior-page .seller dt{color:#9f9f9f}
.interior-page .site-footer{border-top:1px solid #3d3d3d;background:#131313;max-width:none}
.interior-page .footer-top>div{color:#aeaeae}
.interior-page .footer-top .small-label{color:#d5d5d5}
.interior-page .footer-bottom,.interior-page .preview-note{color:#959595}
@media(min-width:1600px){.research-reading-note,.system-boundaries,.interior-page .company-details,.interior-page .site-footer{padding-inline:max(var(--pad),calc((100vw - 1440px)/2))}}
@media(max-width:1100px){
 .chapter-hero{gap:7%;grid-template-columns:1.15fr 1fr}
 .chapter-hero-copy>p{font-size:18px}
 .chapter-feature{gap:7%}
 .interior-page .guide-section{grid-template-columns:.85fr 1.45fr;column-gap:7%}
 .interior-page .guide-heading h2{font-size:32px}
 .interior-page .research-row{grid-template-columns:135px 1fr 65px 16px;gap:20px}
 .question-directory-layout{grid-template-columns:200px 1fr;gap:40px}
 .company-signature{gap:7%}
 .company-signature h2{font-size:36px}
 .company-signature-mark{min-height:350px;padding:35px}
 .scope-visual,.invariance-visual{padding:22px}
 .word-pair>span:not(.relation){font-size:18px}
 .scope-source>strong{font-size:21px}
 .context-visual{padding:10px}
 .context-visual .word-pair>span:not(.relation){font-size:24px}
}
@media(max-width:760px){
 .chapter-hero{display:block;padding-top:42px;padding-bottom:44px}
 .chapter-hero h1{font-size:47px;line-height:1.09}
 .chapter-hero-copy{margin-top:26px;padding:0;max-width:none}
 .chapter-hero-copy>p{font-size:17px;line-height:1.8}
 .chapter-hero-copy>.chapter-link{margin-top:20px}
 .chapter-link{font-size:13px;gap:19px}
 .chapter-feature{grid-template-columns:1fr;gap:32px;padding-top:10px;padding-bottom:50px}
 .chapter-feature h2{font-size:36px;line-height:1.14}
 .chapter-feature>div>p{font-size:16px;line-height:1.8;margin-top:21px}
 .chapter-feature .chapter-link{margin-top:20px}
 .student-feature>.specimen-reading{grid-row:1}
 .specimen-reading,.specimen-class{padding:24px}
 .specimen-heading{font-size:11px;gap:20px;padding-bottom:18px}
 .specimen-reading>.specimen-question{font-size:25px!important;margin-block:22px!important}
 .specimen-answer-pair strong{font-size:47px}
 .specimen-answer-pair span{font-size:11px}
 .specimen-reading>.specimen-insight{font-size:13px!important}
 .specimen-class>p{font-size:23px!important}
 .chapter-contents{gap:12px 22px;padding-block:18px}
 .chapter-contents>a{font-size:11px;line-height:1.6}
 .interior-page .guide-section{display:block;padding-block:42px 48px}
 .interior-page .guide-section>.guide-heading{max-width:none;margin-bottom:28px}
 .interior-page .guide-heading h2{font-size:33px}
 .interior-page .guide-heading>div>p{font-size:15px;margin-top:19px}
 .interior-page .guide-rows h3{font-size:22px}
 .interior-page .guide-rows p{font-size:14px;line-height:1.9}
 .interior-page .guide-rows article:first-child{padding-top:22px;border-top:1px solid #404040}
 .interior-page .journey-ledger article{gap:13px 18px}
 .interior-page .journey-ledger h3{font-size:22px}
 .interior-page .journey-ledger p{font-size:14px}
 .interior-page .assessment-catalog>a{padding:27px}
 .interior-page .assessment-catalog h3{font-size:39px}
 .interior-page .assessment-catalog p{font-size:15px;margin-top:20px}
 .interior-page .assessment-catalog>a>div>span:last-child{font-size:12px;margin-top:26px}
 .interior-page .audience-hero{padding-block:43px}
 .interior-page .audience-hero h1{font-size:45px;line-height:1.11}
 .interior-page .audience-deck{font-size:17px}
 .interior-page .role-paths h3{font-size:27px}
 .interior-page .role-paths p{font-size:15px}
 .interior-page .audience-faq summary{font-size:17px}
 .interior-page .audience-faq details>p,.interior-page .audience-faq details>div{font-size:14px}
 .interior-page .audience-next{padding-block:42px}
 .interior-page .audience-next h2{font-size:39px}
 .interior-page .report-explorer{padding:23px}
 .interior-page .report-explorer-top{font-size:10px}
 .interior-page .report-explorer blockquote{font-size:18px}
 .interior-page .report-explorer h3{font-size:25px}
 .interior-page .report-tabs{gap:18px}
 .interior-page .report-tabs button{font-size:12px}
 .interior-page .report-field-list p{font-size:14px}
 .research-in-context{grid-template-columns:1fr;gap:32px;padding-top:5px;padding-bottom:48px}
 .context-visual{padding:6px}
 .context-visual .invariance-visual{min-height:275px;padding:23px}
 .context-visual .word-pair>span:not(.relation){font-size:22px}
 .context-visual .invariance-visual>p{font-size:13px}
 .research-in-context h2{font-size:37px}
 .research-in-context>div>p{font-size:16px;margin-top:23px}
 .interior-page .research-index{padding-bottom:50px}
 .interior-page .research-filters{gap:7px;margin-bottom:25px}
 .interior-page .research-filters button{font-size:12px;padding:9px 12px}
 .interior-page .research-row{grid-template-columns:1fr 18px;gap:12px;padding-block:25px}
 .interior-page .research-row>span:first-child{grid-column:1;font-size:12px}
 .interior-page .research-row>div{grid-column:1;grid-row:2}
 .interior-page .research-row>span:last-child{grid-column:2;grid-row:2}
 .interior-page .research-row h3{font-size:25px}
 .interior-page .research-row p{font-size:14px}
 .research-reading-note{padding-block:40px 45px}
 .research-reading-note h2{font-size:31px}
 .research-reading-note p{font-size:15px}
 .interior-page .research-article>header{margin-top:32px}
 .interior-page .research-article h1{font-size:44px;line-height:1.12}
 .interior-page .article-deck{font-size:19px}
 .article-illustration{margin-top:32px}
 .article-illustration>.scope-visual{display:flex;gap:0;padding:27px;min-height:290px}
 .article-illustration .scope-source{padding-bottom:23px;border-bottom:1px solid #a4a4a4}
 .article-illustration .scope-source>strong{font-size:26px}
 .article-illustration .scope-source>span{font-size:13px}
 .article-illustration .scope-claims{border:0;padding:24px 0 0;gap:22px}
 .article-illustration .scope-claims strong{font-size:17px}
 .article-illustration .scope-claims small{font-size:13px}
 .article-illustration>.invariance-visual{padding:25px;min-height:270px}
 .article-illustration .word-pair>span:not(.relation){font-size:21px}
 .article-illustration .invariance-visual>p{font-size:13px}
 .article-illustration>.observation-visual{padding:25px;grid-template-columns:1.15fr .35fr 1fr;min-height:280px}
 .article-illustration .observation-paths>div{font-size:16px}
 .article-illustration .observed-answer>strong{font-size:66px}
 .article-illustration>figcaption{font-size:11px}
 .interior-page .article-layout{grid-template-columns:1fr;gap:30px;padding-top:30px}
 .interior-page .perspective-prose{font-size:16px}
 .interior-page .perspective-prose .perspective-lead{font-size:19px}
 .interior-page .perspective-formula{padding:23px}
 .interior-page .perspective-formula p{font-size:13px}
 .interior-page .article-layout>aside{font-size:12px;line-height:1.6}
 .interior-page .article-layout>aside>span{font-size:11px}
 .system-explorer{padding-top:5px;padding-bottom:50px}
 .explorer-title{display:block;margin-bottom:30px}
 .explorer-title h2{font-size:36px}
 .explorer-title>p{font-size:15px;margin-top:22px}
 .workflow-tabs button{font-size:13px;padding:14px 0}
 .system-state{grid-template-columns:1fr;gap:28px;padding-top:28px;min-height:0}
 .system-state-copy h3{font-size:28px;margin-top:0}
 .system-state-copy>p{font-size:16px;line-height:1.8;margin-top:21px}
 .system-state-copy .chapter-link{margin-top:20px}
 .system-state-record{padding:25px}
 .system-state-record>strong{font-size:52px}
 .system-state-record>strong.record-phrase{font-size:29px}
 .system-state-record>p{font-size:15px}
 .system-perspectives{grid-template-columns:1fr;gap:32px;padding-block:45px}
 .system-perspectives h2{font-size:34px}
 .system-perspectives>div>p{font-size:16px}
 .system-perspective-links h3{font-size:23px}
 .system-perspective-links p{font-size:14px}
 .system-boundaries{padding-block:40px 45px}
 .system-boundaries>h2{font-size:33px}
 .system-boundaries>div{grid-template-columns:1fr;gap:30px;margin-top:30px}
 .system-boundaries p{font-size:15px;margin-top:15px}
 .chapter-contact{padding-block:45px 55px}
 .chapter-contact h2{font-size:36px}
 .chapter-contact>p{font-size:16px;margin-top:22px}
 .chapter-contact>div{gap:17px;flex-direction:column;align-items:flex-start}
 .company-signature{grid-template-columns:1fr;gap:35px;padding-top:0;padding-bottom:50px}
 .company-signature-mark{min-height:280px;padding:30px;font-size:99px;line-height:.85}
 .company-signature-mark>span{font-size:13px;margin-top:25px}
 .company-signature h2{font-size:35px;line-height:1.15}
 .company-signature>div>p{font-size:16px;margin-top:22px}
 .interior-page .company-essay{padding-block:45px}
 .interior-page .company-essay>div{display:block}
 .interior-page .company-essay h2{font-size:32px;margin-bottom:25px}
 .interior-page .company-essay p{font-size:16px;margin-top:20px}
 .interior-page .company-essay a{font-size:13px;display:inline-block;margin-top:24px}
 .company-principles{padding-block:42px 50px}
 .company-principles>h2{font-size:34px}
 .company-principles>div{grid-template-columns:1fr;gap:30px;margin-top:30px}
 .company-principles h3{font-size:24px}
 .company-principles p{font-size:15px;margin-top:16px}
 .interior-page .company-details{padding-block:43px}
 .interior-page .principles-opening{padding-block:43px}
 .interior-page .principles-opening h1{font-size:43px}
 .question-directory{padding-bottom:45px}
 .question-search{margin-bottom:30px}
 .question-search>label{font-size:13px;margin-bottom:12px}
 .question-search>div{padding:12px 15px;gap:8px}
 .question-search input{font-size:16px}
 .question-search>p{font-size:12px}
 .question-directory-layout{grid-template-columns:1fr;gap:32px}
 .question-categories{position:static;display:flex;flex-direction:row;flex-wrap:wrap;gap:8px;border:0}
 .question-categories button{font-size:12px;padding:9px 11px;border:1px solid #515151;gap:10px}
 .question-categories button[aria-pressed=true]{border:1px solid #919191;padding:9px 11px}
 .question-categories button>span{font-size:10px}
 .question-group{margin-bottom:38px}
 .question-group h2{font-size:29px;margin-bottom:22px}
 .question-group .audience-faq .chapter-link{font-size:12px}
 .question-empty h2{font-size:29px}
 .interior-page .subhero{padding-block:43px}
 .interior-page .subhero h1{font-size:44px}
 .interior-page .subhero>p:not(.eyebrow){font-size:17px}
 .interior-page .exercise{padding-block:42px}
 .interior-page .exercise h2{font-size:37px}
 .interior-page .passage>p:not(.source-note){font-size:17px;line-height:1.9}
 .interior-page .answer-option{font-size:14px;padding:15px 12px}
 .interior-page .academy-contact>p:not(.eyebrow){font-size:15px}
 .interior-page .academy-pricing .section-intro>p{font-size:15px}
 .scope-visual,.invariance-visual{padding:25px;min-height:270px}
 .word-pair>span:not(.relation){font-size:21px}
 .page-index .direction-figure:has(.clarity-visual){min-height:270px}
 .page-index .direction-grid .type-figure{min-height:230px}
 .observation-visual{padding:26px;grid-template-columns:1.2fr .35fr 1fr;min-height:300px}
 .observation-paths{gap:40px}
 .observation-paths>div{font-size:16px;padding:15px 0}
 .path-convergence{height:113px;margin-right:16px}
 .path-convergence:after{width:16px}
 .observed-answer{padding-left:9px}
 .observed-answer>strong{font-size:70px}
 .observed-answer>span{font-size:12px}
 .observation-visual>p{font-size:16px;margin-top:27px;padding-top:20px}
 .page-index .feature-diagram:has(.clarity-visual),.page-index .feature-diagram>.clarity-visual{min-height:320px}
}
/* Keep audience headlines in deliberate phrases rather than orphaned words. */
.page-students .chapter-hero h1,.page-educators .chapter-hero h1,.page-company .chapter-hero h1{font-size:clamp(48px,5.1vw,74px);line-height:1.1}
@media(max-width:760px){.page-students .chapter-hero h1,.page-educators .chapter-hero h1,.page-company .chapter-hero h1{font-size:40px;line-height:1.14}}
/* Diagram captions inherit their illustration palette, not the surrounding dark card. */
.scope-visual{background:#656565}
.page-index .direction-grid .invariance-visual>p{color:#4b4b4b;font-size:12px;line-height:1.5;margin-top:14px;max-width:none}
@media(max-width:760px){.page-index .direction-grid .invariance-visual>p{font-size:13px}}