/* OnTrick Maths – complete static CSS, v7, no CDN / external dependencies. */
@charset "UTF-8";
/* OnTrick Maths / hand-built editorial interface, zero external dependencies */
:root{--paper:#f7f5ee;--white:#fffdf7;--ink:#17342d;--green:#234e42;--rust:#b55e42;--muted:#718075;--line:#d6d9cb;--serif:Georgia,'Times New Roman',serif;--sans:Arial,Helvetica,sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{background:var(--paper);margin:0;color:var(--ink);font:15px/1.7 var(--sans);-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}a:hover{color:var(--rust)}button,input,select{font:inherit}button{cursor:pointer}svg{max-width:100%}h1,h2,h3,p{margin-top:0}h1,h2,h3{line-height:1.15}h1,h2{letter-spacing:-.053em;font-family:var(--serif);font-weight:400}h1 em,h2 em{color:var(--rust);font-weight:400}.container{width:min(1230px,calc(100% - 80px));margin:auto}.skip-link{position:fixed;top:-100px;left:15px;z-index:100;background:#fff;padding:10px 20px}.skip-link:focus{top:15px}.topline{background:var(--ink);color:#d7e1d7}.topbar{height:34px;display:flex;align-items:center;justify-content:space-between;font-size:10px;font-weight:700;letter-spacing:.12em}.top-dot{display:inline-block;background:#d9b48f;width:6px;height:6px;border-radius:50%;margin-right:10px}.topbar b{color:#95b4a6;margin:0 12px}.site-header{background:var(--paper);border-bottom:1px solid var(--line);position:relative;z-index:10}.header-inner{height:92px;display:flex;align-items:center;gap:26px}.brand{display:flex;align-items:center;gap:10px;flex-shrink:0;line-height:1}.brand-mark{background:var(--green);height:42px;width:42px;border-radius:50%;font:italic bold 32px var(--serif);color:#fff;display:grid;place-items:center;position:relative;transform:rotate(-8deg)}.brand-mark span{position:absolute;color:#e3b696;font-size:23px;right:3px;top:9px}.brand-text{font-size:30px;font-weight:900;letter-spacing:-.09em}.brand-dot,.footer-logo span{color:var(--rust)}.brand-text small{display:block;font:800 9px var(--sans);color:var(--muted);letter-spacing:.13em;margin-top:7px}.desktop-nav{display:flex;gap:24px;margin-left:auto;align-items:center}.nav-link{font-size:12px;font-weight:800;position:relative;padding:12px 0;white-space:nowrap}.nav-link.active,.nav-link:hover{color:var(--rust)}.nav-link.active:after{content:'';position:absolute;height:2px;bottom:6px;left:0;right:0;background:var(--rust)}.header-actions{display:flex;gap:7px}.icon-btn{height:39px;width:39px;display:grid;place-items:center;color:var(--ink);background:none;border:1px solid var(--line)}.icon-btn:hover{background:#e1e7dd}.icon-btn svg,.search-field svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round}.menu-trigger,.mobile-nav[hidden]{display:none!important}.home-main{padding-top:30px}.hero{display:grid;grid-template-columns:51% 49%;background:#e9ede2;min-height:625px;overflow:hidden}.hero-left{padding:77px 34px 28px 65px}.hero-kicker,.eyebrow{font-size:10px;letter-spacing:.15em;font-weight:800;color:var(--rust)}.hero-kicker{display:flex;gap:12px;align-items:center;color:#557368}.line-mark{height:1px;width:27px;background:#557368}.hero h1{font-size:clamp(50px,5.6vw,79px);line-height:1.06;max-width:650px;margin:30px 0 25px}.hero h1 em{font-style:italic}.hero-left>p{font-size:14px;line-height:1.95;max-width:420px;color:#526359}.hero-actions{display:flex;gap:24px;align-items:center;flex-wrap:wrap;margin-top:39px}.btn-primary{background:var(--ink);padding:16px 21px;color:white;display:inline-flex;justify-content:space-between;gap:30px;align-items:center;font-size:12px;font-weight:800}.btn-primary:hover{background:var(--rust);color:white}.btn-primary span,.hero-inline span,.simple-cta span{font-size:20px}.hero-inline{font-size:12px;font-weight:800;padding-bottom:7px;border-bottom:1px solid #93a49a}.hero-inline span{margin-left:9px}.hero-foot{border-top:1px solid 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b{color:var(--rust)}.hero-stamp{border:2px solid var(--rust);background:#f2e4ca;color:var(--rust);height:100px;width:100px;border-radius:50%;position:absolute;right:4%;top:14%;display:grid;place-items:center;text-align:center;font:italic bold 17px/1.1 var(--serif);transform:rotate(16deg)}.art-note{position:absolute;bottom:5%;right:6%;color:var(--green);font:italic 20px var(--serif);transform:rotate(-5deg)}.art-note span{border-bottom:2px solid var(--rust)}.section-spacing{margin-top:104px}.intro-strip{border-bottom:1px solid var(--line);margin-top:0;min-height:120px;display:flex;justify-content:space-between;align-items:center;gap:22px}.intro-strip>span:first-child{font-size:10px;font-weight:800;letter-spacing:.14em;color:var(--rust);white-space:nowrap}.intro-strip p{margin:0;font:24px/1.5 var(--serif);max-width:none}.intro-strip em{color:var(--rust)}.strip-star{color:#a2b3a6;font-size:38px}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:45px;margin-bottom:34px}.section-heading h2{font-size:clamp(42px,4.1vw,60px);margin:14px 0 0}.section-heading p{font-size:13px;color:var(--muted);max-width:300px;line-height:1.85;margin:0}.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.topic-tile{min-height:405px;padding:29px 29px 22px;display:flex;flex-direction:column;transition:transform .2s}.topic-tile:hover{transform:translateY(-5px);color:var(--ink)}.paper-a{background:#eae5d9}.paper-b{background:#e6eae1}.paper-c{background:#eee0d6}.topic-top{display:flex;justify-content:space-between;font-size:10px;font-weight:800;letter-spacing:.13em;color:#657267}.topic-symbol{height:74px;width:74px;border:1px solid #b8baae;border-radius:50%;font:italic 48px var(--serif);color:var(--rust);display:grid;place-items:center;transform:rotate(-12deg)}.topic-tile-copy{margin-top:33px}.topic-tile h3{font:36px/1.07 var(--serif);letter-spacing:-.045em;max-width:280px;margin-bottom:12px}.topic-tile h4{font-size:13px;margin-bottom:10px}.topic-tile p{font-size:12px;line-height:1.8;max-width:265px;color:#647269}.topic-bottom{border-top:1px solid #b9bfb4;padding-top:17px;margin-top:auto;display:flex;justify-content:space-between;font-size:11px;font-weight:800}.topic-bottom span{font-size:19px}.split-section,.reading-section{border-top:1px solid var(--line);padding-top:60px}.feature-grid{display:grid;grid-template-columns:1.07fr .93fr;gap:50px}.feature-article{background:#eee9de;padding:26px 32px 31px;display:flex;flex-direction:column}.feature-article:hover{color:var(--ink);background:#e9e2d3}.feature-label{font-size:10px;letter-spacing:.14em;font-weight:800;color:var(--rust)}.feature-diagram{height:218px;margin:20px 0 26px;position:relative;background:repeating-linear-gradient(0deg,transparent 0 28px,#c8cdbb 29px),repeating-linear-gradient(90deg,transparent 0 28px,#c8cdbb 29px)}.f-equation{position:absolute;left:14%;top:28%;font:clamp(38px,4vw,62px) var(--serif);color:var(--green);transform:rotate(-4deg);letter-spacing:-.06em}.f-equation i{color:var(--rust);padding:0 5px}.f-pencil{position:absolute;right:20%;top:13%;font:italic 22px var(--serif);color:var(--rust);transform:rotate(12deg)}.f-caption{position:absolute;right:5%;bottom:12%;font:italic 16px var(--serif);color:var(--rust)}.f-tick{position:absolute;left:15%;top:20%;height:90px;border-left:2px solid #d3a780;transform:rotate(-30deg)}.feature-article h3{font:35px/1.13 var(--serif);letter-spacing:-.035em;margin-bottom:13px}.feature-article p{font-size:12px;line-height:1.85;color:#6c766b}.text-link{border-top:1px solid #c5c9bb;display:flex;justify-content:space-between;padding-top:16px;margin-top:auto;font-size:12px;font-weight:800}.text-link b{font-size:19px}.feature-side{padding:20px 0}.feature-side-head p{font:18px/1.6 var(--serif);color:var(--muted);margin:15px 0 25px;max-width:330px}.mini-link{border-top:1px solid var(--line);padding:23px 0;display:flex;justify-content:space-between;gap:24px;align-items:center;font:21px/1.3 var(--serif);letter-spacing:-.018em}.mini-link>span:last-child{font:21px var(--sans);color:var(--rust)}.simple-cta{display:flex;justify-content:space-between;border-top:1px solid var(--ink);padding-top:18px;font-size:12px;font-weight:800}.section-all{font-size:12px;font-weight:800;white-space:nowrap;border-bottom:1px solid var(--ink);padding-bottom:7px}.section-all span{font-size:19px}.reading-list,.archive-list,.related-posts{border-top:1px solid var(--ink)}.post-entry{display:grid;grid-template-columns:185px minmax(0,1fr) 27px;gap:24px;align-items:center;padding:27px 0;border-bottom:1px solid var(--line)}.post-entry:hover{padding-left:5px}.post-meta-label{font:800 10px var(--sans);color:#6e7d72;letter-spacing:.04em;text-transform:uppercase}.post-meta-label i{color:var(--rust);padding:0 4px}.post-entry-title{font:24px/1.25 var(--serif);letter-spacing:-.024em}.post-entry-summary{display:none}.post-entry-arrow{color:var(--rust);font-size:21px;text-align:right}.tools-section{background:var(--ink);color:#f7f6ed;display:grid;grid-template-columns:1fr 1fr;gap:80px;padding:61px 68px 70px}.eyebrow.light{color:#dbab94}.tools-lead h2{font-size:clamp(42px,4vw,58px);margin:20px 0}.tools-lead h2 em{color:#e4b69f}.tools-lead>p{font-size:13px;line-height:1.9;color:#bbc9bb;max-width:350px}.tools-scribble{font:italic 70px var(--serif);color:#aabca8;text-align:center;transform:rotate(-10deg)}.tools-list{align-self:center}.tool-line{display:flex;align-items:center;gap:22px;padding:23px 0;border-bottom:1px solid #527569}.tool-line:first-child{border-top:1px solid #527569}.tool-line:hover{color:#e4b69f}.tool-numeral{font:italic 27px var(--serif);color:#a6c0b0}.tool-line>span:nth-child(2){flex:1}.tool-line strong{font:22px var(--serif);display:block}.tool-line small{color:#aebfb3;font-size:11px;line-height:1.6;display:block;margin-top:5px}.tool-cta{font-size:21px}.last-word{text-align:center;margin-top:112px;padding-bottom:100px}.last-word blockquote{max-width:760px;margin:20px auto;font:italic clamp(36px,4vw,56px)/1.3 var(--serif);letter-spacing:-.04em}.last-word p{max-width:550px;color:var(--muted);font-size:13px;line-height:1.9;margin:0 auto 23px}.last-word a{font-size:12px;font-weight:800;border-bottom:1px solid var(--ink);padding-bottom:7px}.site-footer{background:#e8eadf;border-top:1px solid var(--line);padding-top:72px}.footer-top{display:flex;justify-content:space-between;gap:70px;padding-bottom:70px}.footer-kicker{color:var(--rust);font-size:10px;letter-spacing:.14em;font-weight:800}.footer-logo{font-size:60px;line-height:1.3;font-weight:900;letter-spacing:-.09em}.footer-top p{font:15px/1.7 var(--serif);color:var(--muted)}.footer-links{display:flex;gap:90px}.footer-links>div{display:flex;flex-direction:column;gap:11px;min-width:140px}.footer-links b{font-size:11px;letter-spacing:.12em;text-transform:uppercase;margin-bottom:11px}.footer-links a{font-size:12px;color:#69766a}.footer-bottom{border-top:1px solid #cbd1c5;padding:21px 0 27px;display:flex;justify-content:space-between;gap:25px;font-size:10px;color:#788477}.footer-bottom>div{display:flex;justify-content:end;flex-wrap:wrap;gap:12px 17px}
/* Archive, directory and search */
.archive-page,.directory-page,.search-page{padding-top:75px;padding-bottom:115px;min-height:65vh}.archive-top{border-bottom:1px solid var(--line);padding-bottom:43px}.archive-top h1{font-size:clamp(53px,6.5vw,80px);max-width:875px;margin:15px 0 23px}.archive-top>p,.directory-intro p{color:#68776b;font:19px/1.7 var(--serif);max-width:710px}.archive-controls{display:flex;justify-content:space-between;align-items:center;gap:20px;margin:26px 0}.archive-filters{display:flex;gap:9px;flex-wrap:wrap}.filter-btn{background:transparent;border:1px solid var(--line);padding:9px 14px;color:var(--ink);font-size:11px;font-weight:800}.filter-btn.selected{background:var(--ink);color:white;border-color:var(--ink)}#archive-count{font-size:11px;color:var(--muted)}.archive-list .post-entry{row-gap:8px;grid-template-columns:200px minmax(0,1fr) 30px}.archive-list .post-entry-title{font-size:27px}.archive-list .post-entry-summary{display:block;grid-column:2;font-size:12px;line-height:1.6;color:var(--muted)}.archive-list .post-entry-arrow{grid-column:3;grid-row:1/4}.filter-item[hidden]{display:none}.directory-intro{padding-bottom:43px}.directory-intro h1{font-size:clamp(57px,7vw,90px);margin:12px 0}.dir-period{color:var(--rust)}.directory-list{border-top:1px solid var(--ink)}.directory-row{display:grid;grid-template-columns:95px minmax(0,1fr) 27px;gap:30px;align-items:center;padding:30px 0;border-bottom:1px solid var(--line)}.dir-counter{font:italic 31px var(--serif);color:var(--rust)}.directory-row b{display:block;font:clamp(22px,2.7vw,35px)/1.2 var(--serif);letter-spacing:-.025em}.directory-row small{display:block;font-size:12px;line-height:1.65;margin-top:8px;max-width:690px;color:var(--muted)}.dir-arrow{font-size:22px;color:var(--rust)}.dir-end{display:flex;justify-content:space-between;margin-top:30px;font-size:10px;font-weight:800;letter-spacing:.1em;color:var(--muted);text-transform:uppercase}
/* Full-length teaching articles */
.article-page{padding-top:40px;padding-bottom:110px}.breadcrumb,.breadcrumbs{display:flex;flex-wrap:wrap;gap:11px;color:#718174;font-size:11px;margin-bottom:41px}.breadcrumb span{color:#c4cbbc}.article-layout{display:grid;grid-template-columns:minmax(0,780px) minmax(0,300px);gap:72px;align-items:start}.article-header{border-bottom:1px solid var(--line);padding-bottom:25px;margin-bottom:33px}.article-category{font-size:10px;letter-spacing:.14em;text-transform:uppercase;font-weight:800;color:var(--rust)}.article-header h1{font-size:clamp(42px,5.1vw,70px);margin:20px 0 28px}.article-byline{display:flex;flex-wrap:wrap;gap:13px;color:#778477;font-size:11px;font-weight:700}.byline-sep{color:#bbc3b9}.reading-content p,.article-end p{font:17px/1.85 var(--serif);color:#40584d;margin-bottom:23px}.reading-content h2,.legacy-post h2{font:38px/1.23 var(--serif);letter-spacing:-.036em;margin:45px 0 16px}.reading-content h3,.legacy-post h3{font:27px/1.25 var(--serif);margin:29px 0 14px}.reading-content a:not(.mini-link){color:#9e5338;text-decoration:underline;text-underline-offset:3px}.reading-content ul,.reading-content ol,.imported-page ul,.imported-page ol{padding-left:22px;margin:0 0 27px}.reading-content li,.imported-page li{font:16px/1.8 var(--serif);padding-left:3px;margin-bottom:8px}.reading-content code,.imported-page code{font:90% 'Courier New',monospace;background:#e6e9e0;padding:2px 5px;color:#315346;overflow-wrap:anywhere}.reading-content .equation,.imported-page .equation{padding:23px 27px;background:#e5ebe2;border-left:3px solid var(--green);font:24px/1.6 var(--serif);color:var(--green);margin:28px 0;overflow-wrap:anywhere}.reading-content .worked,.imported-page .worked{background:var(--white);border:1px solid var(--line);padding:25px 29px;margin:27px 0}.reading-content .tip,.imported-page .tip{background:#e5ebe2;border-left:3px solid #7c9a79;padding:23px 26px;margin:25px 0;font:16px/1.8 var(--serif)}.reading-content .warning,.imported-page .warning{background:#f2e3d8;border-left:3px solid var(--rust);padding:23px 27px;margin:25px 0}.reading-content .answer,.imported-page .answer{color:var(--green);font-weight:bold}.reading-content details,.imported-page details{border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:16px 0;margin:18px 0}.reading-content summary,.imported-page summary{font:800 13px var(--sans);color:var(--green);cursor:pointer}.article-rail{position:sticky;top:26px}.rail-card{background:#e5e9de;padding:26px}.rail-card p{font:18px/1.65 var(--serif);margin:13px 0;color:#536b5e}.rail-doodle{font:italic 45px var(--serif);color:var(--rust);display:block;text-align:right}.rail-nav{margin-top:33px}.rail-nav .eyebrow{display:block;margin-bottom:12px}.rail-nav .mini-link{font-size:16px;padding:14px 0}.article-end{margin-top:51px;border-top:1px solid var(--ink);padding-top:21px}.article-end>span{font-size:10px;font-weight:800;letter-spacing:.13em;color:var(--rust)}.article-end p{font-size:16px}.article-back{font-size:12px;font-weight:800}.related-posts{margin-top:82px}.related-posts .section-heading{margin-top:34px}.related-posts .section-heading h2{font-size:40px}.related-posts .post-entry{grid-template-columns:180px minmax(0,1fr) 25px}
/* Full source WordPress page content is preserved; typography is not. */
.content-page,.standard-page{padding-top:55px;padding-bottom:115px;min-height:60vh}.standard-page{max-width:1100px}.standard-note{margin-bottom:15px}.imported-page .wrap{width:100%;margin:auto}.imported-page .article-wrap,.imported-page .content-shell{display:grid;grid-template-columns:minmax(0,770px) minmax(180px,260px);gap:64px;align-items:start}.imported-page h1{font:clamp(43px,5.4vw,70px)/1.15 var(--serif);letter-spacing:-.05em;max-width:850px;margin:12px 0 24px}.imported-page .eyebrow{margin-bottom:12px}.imported-page .lead{font:22px/1.6 var(--serif);color:#657466;max-width:770px;margin:12px 0 29px}.imported-page p{font:16px/1.85 var(--serif);color:#41564b}.imported-page .article p{font-size:17px}.imported-page .article a{color:#9a523b}.imported-page h2{font:clamp(28px,3vw,39px)/1.23 var(--serif);letter-spacing:-.025em;margin:45px 0 17px}.imported-page h3{font:25px/1.25 var(--serif);margin:27px 0 12px}.imported-page .toc,.imported-page aside{border-top:3px solid var(--green);padding-top:17px;position:sticky;top:28px}.imported-page aside h3{font:800 11px var(--sans);letter-spacing:.13em;text-transform:uppercase;margin:0 0 14px}.imported-page aside a{display:block;padding:10px 0;border-bottom:1px solid var(--line);font-size:12px;color:#52685c}.imported-page .breadcrumbs{margin-bottom:23px}.imported-page .article-meta{font-size:11px;color:var(--muted);display:flex;gap:12px;margin-bottom:25px}.imported-page .article-list{border-top:1px solid var(--ink);margin:24px 0 35px}.imported-page .article-row{padding:23px 0;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;gap:25px}.imported-page .article-row h3{font:25px var(--serif);margin:0 0 8px}.imported-page .article-row p{font:13px/1.7 var(--sans);color:var(--muted);margin:0}.imported-page .tag{border:1px solid var(--line);padding:6px 9px;color:var(--green);font:800 10px var(--sans);white-space:nowrap}.imported-page .grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.imported-page .card{padding:22px;background:#ecebdf}.imported-page .card h3{font:22px var(--serif);margin-bottom:8px}.imported-page .card p{font:12px/1.8 var(--sans)}.imported-page hr{border:0;border-top:1px solid var(--line);margin:30px 0}.imported-page .tool{max-width:880px}.imported-page .tool-grid{display:grid;grid-template-columns:1fr 1fr;gap:17px;margin:30px 0 19px}.imported-page .field label{display:block;font:800 12px var(--sans);margin-bottom:9px}.imported-page .field input,.imported-page .field select{border-radius:0;width:100%;min-height:51px;background:#fffefa;border:1px solid #c5d1c5;padding:10px 12px;outline-offset:2px;color:var(--ink)}.imported-page .tool>button{background:var(--green);border:0;color:white;font-size:12px;font-weight:800;min-height:49px;padding:13px 24px}.imported-page .tool>button:hover{background:var(--rust)}.imported-page .result{background:#e6ece1;border-left:3px solid var(--green);padding:21px 25px;min-height:65px;font:18px/1.7 var(--serif);white-space:pre-line;margin:18px 0 33px}.imported-page .result.error{background:#f7e5d8;border-color:var(--rust);color:#944f36}.imported-page .article{min-width:0}
/* Native search modal */
dialog{background:var(--paper);color:var(--ink);border:0;padding:0;width:100%;max-width:min(690px,calc(100vw - 32px));box-shadow:0 26px 100px #10271f7a}dialog::backdrop{background:#17332bad;backdrop-filter:blur(3px)}.search-dialog-inner{padding:32px 34px}.search-top{display:flex;align-items:center;justify-content:space-between;margin-bottom:19px}.close-search{height:34px;width:34px;border:1px solid var(--line);background:transparent;font-size:24px;color:var(--ink)}.search-dialog-inner label{font:31px var(--serif);display:block;margin-bottom:22px}.search-field{display:flex;align-items:center;gap:14px;border-bottom:2px solid var(--green);padding-bottom:12px}.search-field input{border:0;background:transparent;outline:0;flex:1;min-width:0}.search-all{display:inline-block;font-size:12px;font-weight:800;margin-top:20px;color:var(--rust)}#quick-results{max-height:340px;overflow:auto;margin-top:17px}.quick-result{border-bottom:1px solid var(--line);display:flex;gap:4px;flex-direction:column;padding:11px 0}.quick-result span{color:var(--muted);font-size:10px}.quick-result strong{font:18px var(--serif)}.search-page label{font-size:12px;font-weight:800;display:block;margin-bottom:10px}.search-page-input-wrap{display:flex;max-width:760px;border:1px solid #c3c9be;background:white}.search-page-input-wrap input{border:0;outline:0;min-width:0;flex:1;padding:16px 20px}.search-page-input-wrap button{border:0;background:var(--ink);color:white;font-size:12px;font-weight:800;padding:0 22px}.results-count{font-size:12px;color:var(--muted);margin:25px 0}.search-page-results{max-width:950px;border-top:1px solid var(--line)}.search-page-results .post-entry-summary{display:block;grid-column:2;color:var(--muted);font-size:12px}
@media(max-width:1050px){.container{width:calc(100% - 60px)}.desktop-nav{gap:15px}.nav-link{font-size:11px}.hero-left{padding-left:39px}.hero h1{font-size:clamp(48px,5.3vw,65px)}.notebook{height:400px;padding:20px}.feature-grid{gap:30px}.article-layout{gap:35px}.imported-page .article-wrap,.imported-page .content-shell{gap:30px}.tools-section{gap:35px;padding:48px 40px}}@media(max-width:900px){.desktop-nav{display:none}.menu-trigger{display:grid!important}.mobile-nav:not([hidden]){display:flex;flex-direction:column;gap:0;background:var(--paper);padding:8px 35px 25px;box-shadow:0 12px 30px #172b2530}.mobile-nav .nav-link{padding:13px 0;border-bottom:1px solid var(--line);font-size:14px}.mobile-nav .nav-link.active:after{display:none}.header-actions{margin-left:auto}.hero{grid-template-columns:1.07fr .93fr}.hero-left{padding:54px 27px}.hero h1{font-size:clamp(42px,5.8vw,63px)}.hero-foot{margin-top:33px}.notebook{height:355px}.topic-tile{min-height:360px;padding:23px}.topic-tile h3{font-size:31px}.article-layout{grid-template-columns:minmax(0,1fr) 220px}.imported-page .article-wrap,.imported-page .content-shell{grid-template-columns:minmax(0,1fr) 200px}.footer-links{gap:35px}.post-entry{grid-template-columns:135px 1fr 27px;gap:17px}}@media(max-width:700px){.container{width:calc(100% - 34px)}.topbar{justify-content:center}.topbar>span:last-child{display:none}.header-inner{height:73px}.brand-mark{height:35px;width:35px;font-size:28px}.brand-text{font-size:25px}.brand-text small{font-size:7px}.home-main{padding-top:17px}.hero{grid-template-columns:1fr}.hero-left{padding:43px 24px 39px}.hero h1{font-size:clamp(48px,11vw,71px);margin:22px 0}.hero-art{height:380px}.notebook{max-width:395px;height:315px;margin:0 auto;padding:16px}.notebook-graph{height:207px;margin:10px 0 0}.hero-stamp{height:74px;width:74px;font-size:14px;top:8%}.art-note{font-size:17px;bottom:3%}.section-spacing{margin-top:75px}.intro-strip{margin-top:0;padding:25px 0;min-height:auto;align-items:start}.intro-strip p{font-size:19px}.strip-star{display:none}.section-heading{display:block;margin-bottom:27px}.section-heading h2{font-size:clamp(40px,8.7vw,53px)}.section-heading p{margin-top:18px;max-width:520px}.topic-grid,.feature-grid{grid-template-columns:1fr;gap:10px}.topic-tile{min-height:302px}.topic-tile-copy{margin-top:14px}.topic-tile h3{font-size:35px}.topic-tile p{max-width:420px}.topic-symbol{width:61px;height:61px;font-size:40px}.split-section,.reading-section{padding-top:41px}.feature-article{padding:23px}.feature-article h3{font-size:31px}.feature-side{padding:20px 0 0}.mini-link{font-size:19px;padding:17px 0}.post-entry,.archive-list .post-entry,.related-posts .post-entry,.search-page-results .post-entry{grid-template-columns:1fr 25px;gap:6px 12px;padding:23px 0}.post-meta-label{grid-column:1;grid-row:1}.post-entry-title,.archive-list .post-entry-title{grid-column:1;grid-row:2;font-size:24px}.post-entry-arrow,.archive-list .post-entry-arrow{grid-column:2;grid-row:1/3}.archive-list .post-entry-summary,.search-page-results .post-entry-summary{grid-column:1;grid-row:3}.tools-section{display:block;padding:41px 25px}.tools-lead h2{font-size:47px}.tools-scribble{display:none}.tools-list{margin-top:33px}.last-word{margin-top:79px;padding-bottom:65px}.last-word blockquote{font-size:37px}.site-footer{padding-top:50px}.footer-top,.footer-bottom{display:block}.footer-top{padding-bottom:45px}.footer-links{justify-content:space-between;max-width:430px;margin-top:36px}.footer-bottom>div{justify-content:start;margin-top:13px}.archive-page,.directory-page,.search-page{padding:51px 0 75px}.archive-top h1{font-size:clamp(47px,9.6vw,69px)}.archive-controls{display:block}.archive-filters{margin-bottom:14px}.directory-intro h1{font-size:55px}.directory-row{grid-template-columns:43px 1fr 24px;gap:15px;padding:24px 0}.dir-counter{font-size:23px}.directory-row b{font-size:25px}.article-page{padding:23px 0 78px}.breadcrumb,.breadcrumbs{margin-bottom:26px}.article-layout{display:block}.article-rail{display:none}.article-header h1{font-size:clamp(42px,9vw,62px)}.reading-content h2{font-size:31px}.reading-content p{font-size:16px}.reading-content .equation{font-size:20px}.related-posts .section-heading h2{font-size:33px}.content-page,.standard-page{padding:37px 0 77px}.imported-page .article-wrap,.imported-page .content-shell{display:block}.imported-page aside{display:none}.imported-page h1{font-size:43px}.imported-page .lead{font-size:19px}.imported-page .grid,.imported-page .tool-grid{grid-template-columns:1fr}.imported-page .article-row h3{font-size:21px}.imported-page .article-row{align-items:flex-start}.imported-page .tag{font-size:9px}.imported-page .equation{font-size:19px;padding:17px}.imported-page .worked{padding:19px}.search-dialog-inner{padding:22px 20px}.search-dialog-inner label{font-size:26px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}@media print{.topline,.site-header,.site-footer,.article-rail,.related-posts,dialog{display:none!important}body{background:white;color:black}.container{width:100%}.article-layout{display:block}}


/* OnTrick Maths / October 2026 editorial layout. Standalone CSS, no frameworks. */
:root{--paper:#fff;--white:#fff;--ink:#1c2730;--green:#233b55;--rust:#a74d2c;--muted:#5d6670;--line:#dde1e4;--serif:Georgia,"Times New Roman",serif;--sans:Arial,Helvetica,sans-serif}
html{scroll-padding-top:20px}body{background:#fff;color:#1c2730;font:15px/1.65 Arial,Helvetica,sans-serif;-webkit-font-smoothing:auto}
a{color:inherit}a:hover{color:#b04a28}h1,h2,h3{letter-spacing:-.025em}h1,h2{font-family:Arial,Helvetica,sans-serif;font-weight:700}h1 em,h2 em{font-style:normal;color:inherit}.container{width:min(1120px,calc(100% - 52px));margin-left:auto;margin-right:auto}
/* Newspaper-style masthead */
.topline{display:none}.site-header{background:#fff;border:0;position:relative;z-index:20}.masthead-top{height:32px;border-bottom:1px solid #e0e2e2;display:flex;align-items:center;justify-content:space-between;font-size:11px;color:#5f6870}.masthead-top a{text-decoration:underline;text-underline-offset:3px}.masthead-main{min-height:105px;display:flex;align-items:center;justify-content:space-between}.site-header .brand{display:inline-flex;color:#172c42;gap:0}.site-header .brand-text{font-size:37px;font-weight:800;letter-spacing:-.065em;line-height:.95}.site-header .brand-text>span{color:#b64f31}.site-header .brand-text small{font:bold 11px/1.4 Arial,sans-serif;letter-spacing:.03em;margin-top:9px;color:#67727b}.masthead-tag{text-align:right;color:#777d81;font-size:12px}.navigation-wrap{border-top:3px solid #1e3d5d;border-bottom:1px solid #cbd4d9}.navigation-inner{min-height:48px;display:flex;align-items:center;justify-content:space-between}.desktop-nav{margin:0;gap:33px}.desktop-nav .nav-link{font-size:13px;font-weight:700;padding:12px 0}.desktop-nav .nav-link.active{color:#b64f31}.desktop-nav .nav-link.active:after{background:#b64f31;bottom:7px;height:2px}.header-actions{margin-left:auto}.search-trigger,.menu-trigger{border:0;background:transparent;color:#233c55;font:bold 13px Arial,sans-serif;padding:11px 0 11px 14px}.search-trigger:hover,.menu-trigger:hover{color:#b04a28;background:transparent}.menu-trigger{display:none}.mobile-nav[hidden]{display:none!important}
/* Utility classes for new homepage */
.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}.editorial-home{padding-top:33px;padding-bottom:68px}.small-label,.section-label{display:block;font-size:11px;letter-spacing:.045em;color:#64727d;font-weight:700;text-transform:uppercase}.home-intro{display:grid;grid-template-columns:minmax(0,1.62fr) minmax(250px,1fr);gap:56px;padding:25px 0 36px}.intro-main{padding:8px 0 0}.intro-main h1{font-size:clamp(36px,4.25vw,54px);line-height:1.16;letter-spacing:-.045em;margin:18px 0 17px}.intro-main h1 span{color:#485d70;font-weight:400}.intro-main p{font-size:16px;line-height:1.75;color:#3d4e5b;max-width:590px;margin-bottom:24px}.intro-links{display:flex;flex-wrap:wrap;gap:13px 24px;align-items:center}.intro-links a{font-weight:700;font-size:13px;border-bottom:1px solid #8796a3;padding-bottom:3px}.intro-links a:first-child{color:#b04a28;border-color:#b04a28}.find-panel{border-left:1px solid #d5dadc;padding-left:30px}.find-panel h2{font:700 21px Arial,sans-serif;margin:0 0 16px}.inline-search{display:flex;height:42px;border:1px solid #9daab4;background:#fff}.inline-search input{width:100%;min-width:0;padding:0 12px;border:0;outline-color:#264a6b;font-size:13px}.inline-search button{border:0;background:#23415e;color:#fff;padding:0 16px;font-size:12px;font-weight:700}.find-panel>p{font-weight:700;color:#6a7177;font-size:11px;text-transform:uppercase;letter-spacing:.05em;margin:25px 0 7px}.find-panel ul{padding:0;margin:0;list-style:none}.find-panel li{border-bottom:1px solid #e1e5e7}.find-panel li a{display:flex;justify-content:space-between;padding:8px 0;font-size:13px;font-weight:700}.find-panel li span{font-weight:normal;color:#6d808d}.subject-bar{background:#eef2f4;border-block:1px solid #d5dfe5;padding:12px 17px;display:flex;flex-wrap:wrap;align-items:center;gap:8px 24px;font-size:12px}.subject-bar>span{color:#66747f;font-weight:700}.subject-bar a{font-weight:700;color:#213f5b}
/* Main story and recent list */
.home-feature{display:grid;grid-template-columns:minmax(0,1.62fr) minmax(260px,1fr);gap:56px;padding:47px 0 50px;border-bottom:1px solid #ccd5da}.feature-main h2{font-size:33px;line-height:1.2;letter-spacing:-.025em;max-width:650px;margin:13px 0 12px}.feature-main>p{color:#566572;font-size:14px;max-width:590px;margin-bottom:23px}.plain-link{font-size:13px;font-weight:700;color:#1d517a;border-bottom:1px solid #1d517a;padding:0 0 2px}.worked-example{border:1px solid #d7dde0;border-left:4px solid #c85c38;background:#fafafa;margin-bottom:19px;padding:21px 23px}.example-title{font-size:11px;text-transform:uppercase;font-weight:700;color:#6c747b;letter-spacing:.05em}.example-calc{display:flex;justify-content:space-between;align-items:center;gap:12px;margin:22px 0 15px}.example-calc>span{font:25px Georgia,serif;color:#64717e}.example-calc>div{flex:1}.example-calc small{display:block;font-size:11px;color:#68737a;margin-bottom:5px}.example-calc strong{display:block;font:700 32px/1.1 Arial,sans-serif;letter-spacing:-.04em;color:#223a53}.example-calc .answer strong{color:#a84728}.worked-example>p{font-size:12px;line-height:1.6;color:#57626b;margin:0}.feature-aside h2{font:bold 18px Arial,sans-serif;border-bottom:2px solid #233f58;padding-bottom:12px;margin:0}.recent-item{display:block;border-bottom:1px solid #dfe3e5;padding:15px 0 13px}.recent-item small{display:block;color:#6e767d;font-size:10px;margin-bottom:6px}.recent-item strong{font:700 15px/1.45 Arial,sans-serif;display:block}.feature-aside>.plain-link{display:inline-block;margin-top:19px}
/* Article archive, editorial rows */
.home-library,.topic-overview{padding:47px 0 25px}.home-heading{display:flex;justify-content:space-between;align-items:end;gap:20px;margin:0 0 19px}.home-heading h2{font:bold 28px/1.2 Arial,sans-serif;margin:7px 0 0}.home-heading>a{font-weight:700;font-size:12px;color:#245579;white-space:nowrap}.library-layout{display:grid;grid-template-columns:minmax(0,1.7fr) minmax(240px,1fr);gap:54px}.article-index{border-top:2px solid #233d56}.index-entry{display:grid;grid-template-columns:33px 1fr 18px;gap:18px;padding:16px 3px 15px 0;border-bottom:1px solid #e0e4e5}.index-no{font:20px/1.5 Georgia,serif;color:#929ba2}.index-detail small{display:block;font-size:11px;color:#6c7379;margin-bottom:5px}.index-detail strong{font:bold 16px/1.35 Arial,sans-serif;display:block;margin-bottom:5px}.index-desc{display:block;color:#6f787e;font-size:12px;line-height:1.55}.index-entry .arrow{color:#8594a0}.library-aside{border-top:2px solid #233d56;padding-top:17px}.library-aside h3{font:bold 18px Arial,sans-serif;margin:0 0 9px}.library-aside p{font:14px/1.7 Georgia,serif;color:#515e66;margin-bottom:26px}.aside-topic{background:#f4f6f6;padding:18px 20px}.aside-topic b{font-size:12px;display:block;margin-bottom:10px}.aside-topic a{display:block;padding:11px 0;border-bottom:1px solid #dfe3e5;font-size:13px;line-height:1.4}.aside-topic a:last-child{border:0;padding-bottom:0}
/* Themes: text lists rather than symmetric colorful cards */
.topic-overview{border-top:1px solid #cbd3d8;margin-top:30px;padding-bottom:52px}.topic-columns{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:29px}.topic-column{border-top:2px solid #283e52;padding-top:16px}.topic-column h3{font:bold 19px Arial,sans-serif;margin:0 0 8px}.topic-column ul{list-style:none;padding:0;margin:0}.topic-column li{border-bottom:1px solid #e0e4e5;font-size:13px;line-height:1.5}.topic-column li a{display:block;padding:11px 0}.topic-all{display:inline-block;margin-top:15px;color:#245579;font-size:12px;font-weight:700}
.utility-section{border-top:3px solid #284560;background:#f1f4f5;display:grid;grid-template-columns:1fr 1.4fr;gap:50px;padding:26px 31px 29px}.utility-section h2{font:bold 26px Arial,sans-serif;margin:8px 0 10px}.utility-section>div>p{color:#66747d;font-size:13px;line-height:1.65;max-width:390px}.utility-section ul{list-style:none;padding:0;margin:0}.utility-section li{border-bottom:1px solid #d3dbdf}.utility-section li:first-child{border-top:1px solid #d3dbdf}.utility-section li a{display:grid;grid-template-columns:1fr 1.05fr 18px;gap:15px;padding:13px 0;align-items:center;font-size:13px}.utility-section li span{color:#626f79;font-size:12px}.utility-section li em{font-style:normal;color:#9c4427}.end-note{margin-top:38px;font:italic 16px/1.65 Georgia,serif;color:#5d6770;max-width:680px}.end-note a{border-bottom:1px solid #9da7ac}
/* Common subpage layout */
.archive-page,.directory-page,.search-page,.content-page,.standard-page{padding-top:43px}.archive-top,.directory-intro{max-width:760px;margin-bottom:38px}.archive-top h1,.directory-intro h1{font:bold clamp(34px,4.1vw,51px)/1.12 Arial,sans-serif;letter-spacing:-.04em;margin:10px 0 11px}.archive-top p,.directory-intro p{font:15px/1.7 Arial,sans-serif;color:#627079}.archive-top .eyebrow,.directory-intro .eyebrow,.article-header .eyebrow,.standard-note .eyebrow,.imported-page .eyebrow{font-size:11px;color:#62717c;letter-spacing:.04em}.archive-controls{border-top:2px solid #273f55;border-bottom:1px solid #d3dce0;padding:13px 0}.filter-btn{background:#fff;border:1px solid #b7c3ca;border-radius:3px;padding:7px 12px;font-size:12px;color:#2f4555}.filter-btn.selected{background:#24435f;color:white;border-color:#24435f}.archive-list{border-top:0}.archive-list .post-entry,.reading-list .post-entry,.related-posts .post-entry,.search-page-results .post-entry{border-bottom:1px solid #dbe1e4;padding:18px 0;grid-template-columns:175px 1fr 25px;gap:6px 18px}.post-meta-label,.archive-list .post-meta-label{font-size:11px;color:#6e7881;letter-spacing:0;text-transform:none}.archive-list .post-entry-title,.post-entry-title{font:bold 19px/1.38 Arial,sans-serif;letter-spacing:-.012em}.archive-list .post-entry-summary,.post-entry-summary{color:#6e767d;font:12px/1.6 Arial,sans-serif}.archive-list .post-entry-arrow,.post-entry-arrow{color:#617c8c}.directory-list{border-top:2px solid #263e54}.directory-row{padding:19px 0;border-bottom:1px solid #e0e3e5}.directory-row b{font:700 19px/1.35 Arial,sans-serif}.dir-counter{color:#8997a0}.dir-period{color:#b04a28}
/* Long-form pages: calm type, compact body, clear lesson examples */
.article-page{padding-top:30px}.breadcrumb,.breadcrumbs{color:#777f85;font-size:12px}.article-layout{grid-template-columns:minmax(0,730px) minmax(170px,265px);gap:70px}.article-header h1{font:700 clamp(32px,3.55vw,48px)/1.17 Arial,sans-serif;letter-spacing:-.035em;margin-top:12px;margin-bottom:19px}.article-header .article-intro,.article-header>p{font:16px/1.8 Arial,sans-serif;color:#485f6a}.article-meta,.article-meta time{font-size:11px;color:#707b83}.reading-content{font-size:16px}.reading-content p{font:16px/1.8 Arial,sans-serif;color:#293d49}.reading-content h2{font:700 25px/1.35 Arial,sans-serif;letter-spacing:-.02em;margin:37px 0 14px}.reading-content h3{font:700 19px/1.35 Arial,sans-serif}.reading-content .equation,.imported-page .equation{border:1px solid #d4dde2;border-left:3px solid #b45635;background:#f5f7f8;color:#223a50;font:19px/1.8 Georgia,serif;padding:19px 24px}.reading-content .tip,.reading-content .worked{background:#f7f7f4;border:1px solid #e4e5df;padding:19px 24px}.reading-content details{border-color:#d4dae0}.article-rail .rail-nav{border-top:2px solid #30485d;padding-top:12px}.article-rail .mini-link{font:13px/1.5 Arial,sans-serif}.related-posts{margin-top:49px;border-top:1px solid #dbe1e4;padding-top:22px}.related-posts h2{font:bold 22px Arial,sans-serif}.related-posts .section-heading{margin-bottom:15px}.related-posts .section-spacing{margin-top:0}.article-rail .rail-card{display:none}
.imported-page h1{font:700 clamp(30px,3.5vw,48px)/1.2 Arial,sans-serif;letter-spacing:-.03em}.imported-page h2{font:700 25px/1.35 Arial,sans-serif;letter-spacing:-.02em;margin:32px 0 12px}.imported-page h3{font:bold 19px/1.4 Arial,sans-serif}.imported-page p,.imported-page .article p{font:15px/1.8 Arial,sans-serif;color:#354a57}.imported-page .lead{font:17px/1.65 Arial,sans-serif;color:#5d6973}.imported-page aside{border-top:2px solid #29465f}.imported-page .article-wrap,.imported-page .content-shell{gap:45px}.imported-page .tool-grid{margin-top:24px}.imported-page .field label{font-size:12px}.imported-page .field input,.imported-page .field select{border:1px solid #a7b5bf}.imported-page .tool>button{background:#23415e}.imported-page .result{background:#f3f5f6;border-color:#23415e;font:17px/1.6 Arial,sans-serif}.search-dialog-inner label{font:700 24px Arial,sans-serif}.search-dialog-inner .eyebrow{color:#6e7881}.search-all{color:#1d517a}
/* Low-key, content-focused footer */
.site-footer{background:#f1f3f4;border-top:2px solid #263f56;color:#283c4c;padding:35px 0 15px;margin-top:25px}.editorial-footer .footer-content{display:grid;grid-template-columns:2fr 1fr 1fr;gap:40px;border-bottom:1px solid #d4dce0;padding-bottom:33px}.footer-brand{font:bold 23px Arial,sans-serif;letter-spacing:-.035em}.footer-content p{color:#62717b;font-size:12px;line-height:1.65;max-width:350px;margin:10px 0 0}.footer-nav{display:flex;flex-direction:column;align-items:flex-start;gap:7px}.footer-nav strong{font-size:12px;margin-bottom:4px}.footer-nav a{font-size:12px;color:#576c7b}.footer-legal{display:flex;justify-content:space-between;gap:17px;align-items:center;padding-top:16px;color:#62717b;font-size:11px}.footer-legal>div{display:flex;gap:17px;flex-wrap:wrap}
@media(max-width:930px){.container{width:calc(100% - 42px)}.desktop-nav{gap:18px}.masthead-tag{display:none}.home-intro,.home-feature{gap:27px}.library-layout{gap:30px}.topic-columns{gap:17px}.article-layout{gap:30px;grid-template-columns:minmax(0,1fr) 210px}}
@media(max-width:720px){.container{width:calc(100% - 32px)}.masthead-main{min-height:79px}.masthead-top{height:28px;font-size:10px}.site-header .brand-text{font-size:30px}.site-header .brand-text small{font-size:9px;margin-top:6px}.navigation-inner{min-height:43px}.desktop-nav{display:none}.menu-trigger{display:inline-block}.header-actions{margin-left:auto;display:flex;gap:18px}.search-trigger,.menu-trigger{padding:12px 0;font-size:12px}.mobile-nav:not([hidden]){display:flex;flex-direction:column;padding:5px 16px 15px;box-shadow:0 10px 24px #00000018;background:white}.mobile-nav .nav-link{font-size:13px;border-bottom:1px solid #e5eaed;padding:10px 0}.editorial-home{padding-top:15px}.home-intro,.home-feature,.library-layout,.utility-section{grid-template-columns:1fr;gap:26px}.home-intro{padding:16px 0 24px}.intro-main h1{font-size:clamp(34px,8vw,47px)}.intro-main p{font-size:14px}.find-panel{border-left:0;border-top:1px solid #d9dfe2;padding:20px 0 0}.subject-bar{gap:5px 14px;padding:10px 12px}.home-feature{padding-top:30px}.feature-main h2{font-size:27px}.feature-aside{padding-top:5px}.home-library,.topic-overview{padding-top:32px}.home-heading{align-items:center}.home-heading h2{font-size:23px}.home-heading>a{white-space:normal;text-align:right;font-size:11px}.topic-columns{grid-template-columns:1fr;gap:28px}.topic-column ul{display:grid;grid-template-columns:1fr 1fr;gap:0 18px}.utility-section{padding:21px}.utility-section li a{grid-template-columns:1fr 1fr 16px;gap:10px}.editorial-footer .footer-content{grid-template-columns:1fr 1fr;gap:26px}.editorial-footer .footer-content>div:first-child{grid-column:1/-1}.footer-legal{display:block}.footer-legal>div{margin-top:9px;gap:5px 14px}.archive-page,.directory-page,.content-page,.standard-page{padding-top:29px}.archive-top h1,.directory-intro h1{font-size:36px}.archive-list .post-entry,.search-page-results .post-entry,.related-posts .post-entry{grid-template-columns:1fr 20px;gap:5px 12px}.archive-list .post-meta-label,.archive-list .post-entry-title,.archive-list .post-entry-summary{grid-column:1}.archive-list .post-entry-arrow{grid-column:2;grid-row:1/4}.article-layout{display:block}.article-rail{display:none}.article-header h1{font-size:34px}.reading-content h2{font-size:23px}.imported-page .article-wrap,.imported-page .content-shell{display:block}.imported-page h1{font-size:35px}.imported-page aside{display:none}.imported-page .tool-grid{grid-template-columns:1fr}.reading-content .equation,.imported-page .equation{font-size:17px;padding:15px 18px}}
@media(max-width:420px){.subject-bar{gap:8px 11px}.subject-bar a{font-size:11px}.example-calc{gap:5px}.example-calc strong{font-size:27px}.example-calc small{font-size:10px}.topic-column ul{display:block}.utility-section li a{grid-template-columns:1fr 15px;gap:5px}.utility-section li span{grid-column:1;grid-row:2}.utility-section li em{grid-column:2;grid-row:1/3}.index-entry{gap:12px;grid-template-columns:27px 1fr 13px}}
@media print{.site-header,.site-footer,.find-panel,.feature-aside,.library-aside{display:none!important}.editorial-home,.article-page{padding-top:0}}


/* Readability adjustments; no layout overhaul. */
body{font-size:16px}
.masthead-top,.nav-link,.footer-nav a,.footer-content p,.footer-legal{font-size:13px}
.intro-main p,.find-panel p,.feature-main>p,.utility-section>div>p,.archive-top p,.directory-intro p{font-size:16px;line-height:1.7}
.article-index .index-detail small,.recent-item small,.post-meta-label{font-size:12px}
.archive-list .post-entry-summary,.post-entry-summary{font-size:14px;line-height:1.65}
.imported-page p,.imported-page .article p,.legacy-post p,.legacy-post li{font-size:16px;line-height:1.8}
@media(max-width:720px){.intro-main p{font-size:16px}.footer-nav a,.footer-legal{font-size:13px}}



/* ---------- Header / topic navigation correction, 26 Oct 2026 ---------- */
/* This complete stylesheet deliberately includes the original base and editorial rules.
   The deployed site now needs only one CSS request. */
body{font-size:16px}
.skip-link{position:fixed!important;left:14px!important;top:-140px!important;z-index:9999!important;background:#172f48!important;color:white!important;padding:12px 16px!important;text-decoration:none!important;border-radius:2px!important}
.skip-link:focus{top:12px!important}
.site-header{background:#fff;position:relative;z-index:30}
.site-header a{text-decoration:none}
.site-header a:hover{text-decoration:none}
.site-header .masthead-top{min-height:39px;height:auto;display:flex;gap:20px;justify-content:space-between;align-items:center;border-bottom:1px solid #e3e7e9;color:#647380;font-size:12px;line-height:1.4;padding:8px 0}
.masthead-utility{display:flex;flex-wrap:wrap;align-items:center;gap:22px}
.masthead-utility a{font-size:12px;color:#31475a}
.masthead-utility a:hover,.masthead-utility a:focus-visible{text-decoration:underline;text-underline-offset:4px}
.masthead-main{min-height:113px;display:flex;justify-content:space-between;align-items:center;gap:28px;padding:21px 0 23px}
.site-header .brand{display:inline-flex;flex-direction:column;align-items:flex-start;gap:0;max-width:100%;min-width:0;color:#172f47;text-decoration:none}
.brand-title{display:block;font:800 clamp(31px,3.25vw,43px)/1.04 Arial,Helvetica,sans-serif;letter-spacing:-.055em;white-space:nowrap}
.brand-title .brand-accent{color:#b95030}
.brand-subtitle{display:block;margin-top:9px;color:#607181;font:500 13px/1.5 Arial,Helvetica,sans-serif;letter-spacing:.012em}
.masthead-promise{margin:0;max-width:340px;text-align:right;font:700 15px/1.5 Arial,Helvetica,sans-serif;color:#33475b}
.masthead-promise span{font-size:13px;font-weight:400;color:#6a7783}
.navigation-wrap{border-top:3px solid #25445f;border-bottom:1px solid #d7e0e5;background:#fbfcfd}
.navigation-inner{min-height:57px;display:flex;align-items:center;gap:18px;justify-content:space-between}
.desktop-nav{display:flex;align-items:center;gap:clamp(11px,1.2vw,21px);min-width:0;margin:0;flex-wrap:nowrap}
.desktop-nav .nav-link{font:700 13px/1.3 Arial,Helvetica,sans-serif;padding:19px 0 17px;position:relative;white-space:nowrap;color:#314659}
.desktop-nav .nav-link:hover,.desktop-nav .nav-link.active{color:#a94b2e}
.desktop-nav .nav-link.active:after{background:#a94b2e;bottom:11px;height:2px}
.header-actions{margin-left:auto;display:flex;align-items:center;flex-shrink:0;gap:8px}
.search-trigger,.menu-trigger{display:inline-flex;gap:7px;align-items:center;justify-content:center;color:#25435e;background:transparent;border:0;border-radius:3px;padding:10px 0 10px 10px;font:bold 13px/1.25 Arial,Helvetica,sans-serif;cursor:pointer;white-space:nowrap}
.search-trigger svg,.menu-trigger svg{height:17px;width:17px;display:block;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}
.site-header .search-trigger:hover,.site-header .menu-trigger:hover{background:#edf2f5;color:#b34f31}
.menu-trigger{display:none!important}
.mobile-nav[hidden]{display:none!important}
.site-header :is(a,button):focus-visible{outline:3px solid #b95537;outline-offset:3px}
/* Readable, correctly encoded category list and consistent search form */
.find-panel{border-left:1px solid #d6dfe4;padding-left:30px}
.find-panel h2{font-size:23px;margin:0 0 17px}
.find-panel>p{font-size:12px;margin-top:27px}
.find-panel li a{display:flex;align-items:center;justify-content:space-between;gap:14px;min-height:46px;font-size:15px;font-weight:700;text-decoration:none;padding:11px 1px;color:#21384d}
.find-panel li a:hover{color:#af4d2e;background:#f8fafb}
.find-panel li a .topic-arrow{display:inline-block;width:9px;height:9px;border-right:2px solid #7d909d;border-top:2px solid #7d909d;transform:rotate(45deg);flex:0 0 9px;margin-right:5px;font-size:0}
.find-panel li a:hover .topic-arrow{border-color:#a94b2e;transform:translateX(3px) rotate(45deg)}
.find-panel .inline-search{height:46px}
.find-panel .inline-search input{font-size:15px}
.find-panel .inline-search button{font-size:13px}
/* Show accessible category navigation on smaller screens. */
@media (max-width:1100px){
 .desktop-nav{display:none!important}
 .menu-trigger{display:inline-flex!important}
 .navigation-inner{min-height:54px}
 .mobile-nav:not([hidden]){display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 22px;background:#fbfcfd;box-shadow:0 14px 23px #122f4224;padding:10px max(26px,calc((100vw - 920px)/2)) 23px;border-top:1px solid #dde4e7}
 .mobile-nav .nav-link{border-bottom:1px solid #e2e7ea;padding:13px 2px;font-size:15px;font-weight:650}
 .mobile-nav .nav-link.active{color:#a94b2e}
 .mobile-nav .nav-link.active:after{display:none}
}
@media (max-width:700px){
 .site-header .masthead-top{min-height:35px;font-size:11px;gap:9px}
 .masthead-utility{gap:12px}
 .masthead-utility a{font-size:11px}
 .masthead-main{min-height:101px;padding:19px 0 22px}
 .brand-title{font-size:34px}
 .brand-subtitle{font-size:12px}
 .masthead-promise{display:none}
 .mobile-nav:not([hidden]){grid-template-columns:1fr;padding:8px 18px 19px}
 .find-panel{border-left:0;border-top:1px solid #d6dfe4;padding:23px 0 0;margin-top:10px}
}
@media (max-width:460px){
 .brand-title{font-size:31px}
 .navigation-inner{min-height:52px}
 .masthead-utility a:first-child{display:none}
}


/* OnTrick / layout revision 4, 2026-10-26: readable spaced categories */
body>.skip-link{position:absolute!important;inset:auto auto auto -10000px!important;width:1px!important;height:1px!important;padding:0!important;margin:0!important;overflow:hidden!important;white-space:nowrap!important;clip-path:inset(50%)!important;border:0!important}
body>.skip-link:focus-visible{position:fixed!important;inset:12px auto auto 12px!important;width:auto!important;height:auto!important;padding:12px 18px!important;margin:0!important;clip-path:none!important;overflow:visible!important;z-index:10000!important;color:#fff!important;background:#24435f!important;box-shadow:0 2px 12px #24435f35!important;text-decoration:none!important;border-radius:5px!important}
.navigation-wrap{background:#f8fafb;border-top:1px solid #ced8df;border-bottom:1px solid #d7e0e5}
.navigation-inner{min-height:76px;gap:26px}
.desktop-nav{display:flex;align-items:center;flex:1;gap:26px;min-width:0;margin:0}
.nav-categories,.nav-secondary{display:flex;align-items:center;flex-wrap:nowrap;gap:18px;min-width:0}
.nav-categories{border-right:1px solid #d5e0e7;padding-right:24px;flex-shrink:0}
.nav-categories>.nav-section-label{font-size:11px;letter-spacing:.075em;font-weight:800;color:#566d7f;text-transform:uppercase;margin-right:4px;white-space:nowrap}
.desktop-nav .nav-categories .nav-link{display:inline-flex;justify-content:center;align-items:center;font-size:14px;min-height:43px;padding:9px 15px;border-radius:6px;background:#eaf0f3;border:1px solid #d6e1e7;text-decoration:none;font-weight:700;transition:background .16s ease,color .16s ease}
.desktop-nav .nav-categories .nav-link:hover,.desktop-nav .nav-categories .nav-link.active{background:#25445f;border-color:#25445f;color:white}
.desktop-nav .nav-categories .nav-link.active:after{display:none}
.nav-secondary{gap:clamp(15px,1.45vw,24px);flex:1}
.desktop-nav .nav-secondary .nav-link{padding:16px 0;font-size:13px;line-height:1.4;font-weight:700;text-decoration:none}
.desktop-nav .nav-secondary .nav-link:hover,.desktop-nav .nav-secondary .nav-link.active{color:#a94b2e}
.desktop-nav .nav-secondary .nav-link.active:after{bottom:10px}
.site-header .header-actions{margin-left:auto;padding-left:4px}
.site-header .search-trigger{padding:10px 8px;font-size:13px}
.masthead-top{min-height:40px}
.masthead-main{padding-top:21px;padding-bottom:23px}
.subject-bar{gap:12px 22px;padding:16px 20px}
.subject-bar a{display:inline-block;padding:6px 2px;font-size:14px;text-decoration:none}
.find-panel ul{list-style:none;padding:0;margin:14px 0 0;display:grid;gap:10px}
.find-panel li{border:1px solid #e0e7ec;border-radius:5px;background:#fcfdfe}
.find-panel li a{padding:12px 16px;min-height:54px;gap:20px;text-decoration:none}
.find-panel li:hover{background:#f1f5f7;border-color:#c4d2dd}
@media(max-width:1250px){
 .desktop-nav{display:none!important}
 .menu-trigger{display:inline-flex!important}
 .navigation-inner{min-height:58px}
 .mobile-nav:not([hidden]){display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px 20px;padding:18px max(24px,calc((100vw - 1050px)/2)) 26px;box-shadow:0 12px 28px #17354b1a}
 .mobile-nav .nav-link{display:block;border:1px solid #dce5eb;border-radius:5px;background:#fff;font-size:15px;line-height:1.45;font-weight:700;padding:13px 16px;text-decoration:none}
 .mobile-nav .nav-link:hover,.mobile-nav .nav-link.active{background:#ecf2f5;color:#a54c30;border-color:#b9ccd8}
 .mobile-nav .nav-link.active:after{display:none}
}
@media(max-width:700px){
 .mobile-nav:not([hidden]){grid-template-columns:minmax(0,1fr);gap:9px;padding:14px 20px 22px}
 .masthead-main{padding-top:20px;padding-bottom:22px}
 .subject-bar{gap:6px 14px;padding:12px 13px}
 .subject-bar a{font-size:13px}
 .find-panel ul{gap:9px}
}

/* v5: graceful fallback separators only appear without the stylesheet */
.nav-degrade-separator{display:none!important}



/* OnTrick Maths v7: clean publication header, navigation, footer and readability */
:root{--nt-ink:#1e2d35;--nt-muted:#586b72;--nt-line:#d9e1e2;--nt-blue:#173d4e;--nt-accent:#bc5e3d;--nt-bg:#f9faf8;--nt-paper:#fff}
html{scroll-behavior:smooth}
body{font-family:Arial,Helvetica,sans-serif;font-size:16px;line-height:1.65;color:var(--nt-ink);background:#fff}
.container{max-width:1160px;width:calc(100% - 56px);margin-left:auto;margin-right:auto}
.nt-header,.nt-footer{font-family:Arial,Helvetica,sans-serif;letter-spacing:normal}
.nt-header{background:#fff;border-bottom:1px solid var(--nt-line);position:relative;z-index:30}
.nt-header a{text-decoration:none;color:inherit}
.nt-skip{position:absolute;left:-10000px;top:auto;width:1px;height:1px;overflow:hidden;z-index:9999}
.nt-skip:focus{position:fixed;top:8px;left:8px;width:auto;height:auto;padding:12px 18px;color:#fff;background:#173d4e;outline:2px solid #f1ac70}
.nt-topline{border-bottom:1px solid var(--nt-line);background:#f7f9f9}
.nt-topline-inner{display:flex;justify-content:space-between;align-items:center;min-height:35px;color:#536772;font-size:11px;letter-spacing:.07em;font-weight:700}
.nt-top-links{display:flex;gap:23px;letter-spacing:0;font-size:12px;font-weight:400}
.nt-top-links a:hover{color:var(--nt-accent)}
.nt-brandline{display:flex;align-items:center;justify-content:space-between;min-height:132px;gap:28px;padding-top:22px;padding-bottom:23px}
.nt-logo{display:flex;flex-direction:column;gap:10px;min-width:0}
.nt-name{font-weight:800;letter-spacing:-.055em;font-size:clamp(32px,3.4vw,46px);line-height:1;color:var(--nt-ink)}
.nt-name strong{font-weight:800;color:var(--nt-accent)}
.nt-period{color:var(--nt-blue)}
.nt-tagline{font-size:14px;letter-spacing:0;color:var(--nt-muted);line-height:1.4}
.nt-brand-note{text-align:right;display:flex;flex-direction:column;gap:6px;color:#4c6471;font-size:13px;white-space:nowrap}
.nt-note-kicker{font-weight:800;letter-spacing:.17em;color:var(--nt-blue);font-size:10px}
.nt-nav-shell{background:#f3f6f6;border-top:1px solid var(--nt-line)}
.nt-nav-inner{display:flex;justify-content:space-between;align-items:center;gap:18px;min-height:64px}
.nt-navigation{display:flex;align-items:center;gap:9px;flex-wrap:wrap}
.nt-navigation a{padding:11px 12px;border-radius:5px;display:inline-block;white-space:nowrap;color:#263f4d;font-size:13px;line-height:1.25;font-weight:700}
.nt-navigation a:hover,.nt-navigation a:focus-visible{background:#e4eced;color:#124353;outline:none}
.nt-navigation a[aria-current="page"]{background:#dae7e9;color:#0f4657}
.nt-separator{display:none}
.nt-search-link{display:inline-flex;align-items:center;gap:7px;border:1px solid #c7d7de;padding:9px 13px;background:white;border-radius:4px;font-size:13px;font-weight:700;color:#254758!important;white-space:nowrap}
.nt-search-link span{font-size:19px;line-height:1}
.nt-search-link:hover{background:#e7f0f2}
.nt-mobile{display:none;position:relative}
.nt-footer{background:#eef2f1;border-top:2px solid #2b5260;margin-top:80px;color:#283e48;font-size:14px}
.nt-footer-main{padding-top:53px;padding-bottom:50px;display:grid;grid-template-columns:1.8fr repeat(3,1fr);gap:42px}
.nt-footer-brand{font-size:27px;font-weight:800;letter-spacing:-.045em;color:#203c48;text-decoration:none}
.nt-footer-brand strong{color:var(--nt-accent)}
.nt-footer-about p{color:#586b72;font-size:14px;max-width:285px;margin-top:16px;line-height:1.8}
.nt-footer-group{display:flex;flex-direction:column;align-items:flex-start;gap:11px}
.nt-footer-group h2{font:700 12px/1.3 Arial,Helvetica,sans-serif;text-transform:uppercase;letter-spacing:.13em;margin:0 0 5px;color:#2e4c59}
.nt-footer-group a{font-size:13px;color:#435c66;text-decoration:none}
.nt-footer-group a:hover{text-decoration:underline;color:#b35439}
.nt-footer-bottom{border-top:1px solid #cddad8;min-height:57px;padding:17px 0;display:flex;gap:20px;align-items:center;justify-content:space-between;color:#65767e;font-size:12px}
/* Home and article polish */
main{display:block}
.home-intro{padding-top:56px!important;padding-bottom:38px!important}
.editorial-home h1{letter-spacing:-.04em}
.editorial-home .intro-main p{font-size:17px;line-height:1.8}
.editorial-home .intro-links a,.plain-link{font-weight:700}
.editorial-home .find-panel{border-left-color:#dce4e6}
.editorial-home .inline-search input,.search-page-input-wrap input{min-height:48px}
.editorial-home .find-panel li a{min-height:46px}
.reading-content{font-size:17px;line-height:1.82}
.reading-content p{margin-bottom:1.15em}
.reading-content h2{line-height:1.25}
.reading-content .equation{overflow-wrap:anywhere}
.article-main h1{line-height:1.15}
.directory-intro p,.archive-top p{font-size:17px}
:where(a,button,input,summary,select):focus-visible{outline:3px solid #ca7352;outline-offset:3px}
@media(max-width:1190px){.nt-navigation{gap:2px}.nt-navigation a{padding:10px 8px;font-size:12px}}
@media(max-width:980px){.nt-brand-note{display:none}.nt-navigation{gap:1px}.nt-navigation a{padding:10px 6px;font-size:11.5px}.nt-footer-main{gap:26px}}
@media(max-width:760px){
 .container{width:calc(100% - 36px)}
 .nt-brandline{min-height:102px;padding:18px 0}
 .nt-name{font-size:34px}
 .nt-tagline{font-size:12px}
 .nt-topline-inner{font-size:10px}
 .nt-top-links{gap:13px;font-size:11px}
 .nt-navigation{display:none}
 .nt-nav-inner{min-height:55px;flex-direction:row-reverse;justify-content:space-between;gap:12px}
 .nt-search-link{padding:8px 13px}
 .nt-mobile{display:block}
 .nt-mobile summary{list-style:none;cursor:pointer;font-size:14px;font-weight:700;color:#284858;padding:10px 12px;border:1px solid #c7d7de;border-radius:4px;background:#fff}
 .nt-mobile summary::-webkit-details-marker{display:none}
 .nt-mobile[open] summary{background:#dce9eb}
 .nt-mobile nav{position:absolute;z-index:60;left:0;top:calc(100% + 8px);width:min(310px,calc(100vw - 36px));padding:8px 10px;background:#fff;border:1px solid #cad8de;border-radius:7px;box-shadow:0 18px 30px #18334225;display:flex;flex-direction:column}
 .nt-mobile nav a{padding:11px 12px;font-size:14px;color:#264653;border-bottom:1px solid #ebeff0}
 .nt-mobile nav a:last-child{border:0}
 .nt-footer-main{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px;padding-top:35px;padding-bottom:35px}
 .nt-footer-about{grid-column:1/-1}
 .nt-footer{margin-top:55px}
 .nt-footer-bottom{align-items:flex-start;flex-direction:column;gap:6px}
 .home-intro{padding-top:30px!important}
 .reading-content{font-size:16px}
}
@media(max-width:400px){.nt-topline-inner>span{font-size:9px;letter-spacing:0}.nt-top-links{font-size:10px}.nt-tagline{font-size:11px}.nt-name{font-size:31px}}
@media print{.nt-topline,.nt-nav-shell,.nt-footer{display:none!important}.nt-brandline{min-height:auto}.nt-header{border:0}.nt-logo{color:#000}.nt-brand-note{display:none}}