/* Modern atlas: illustrated chapter plates and calm, colorful reading surfaces. */
body{--paper:#f7f2e9;--surface:#fffdf8;--line:#e2d9ca;--gold:#a06c37;--accent:#93643b;--wash:#ede1ce;--soft:#f5ecdc;background-image:radial-gradient(#8a68470c .6px,transparent .6px);background-size:5px 5px}
body.dark{--paper:#1c2520;--surface:#253027;--line:#435044;--accent:#d3b17e;--wash:#344338;--soft:#28382d;background-image:radial-gradient(#e0c59d0b .6px,transparent .6px)}
body[data-chapter="2"],body[data-chapter="5"],body[data-chapter="9"]{--accent:#4f7770;--wash:#dce9e1;--soft:#ecf1e9}
body[data-chapter="3"],body[data-chapter="4"],body[data-chapter="12"]{--accent:#788052;--wash:#e6e8d6;--soft:#f0f1e4}
body[data-chapter="7"],body[data-chapter="8"]{--accent:#b07a3c;--wash:#efe0c9;--soft:#f7eddf}
body[data-chapter="10"],body[data-chapter="11"],body[data-chapter="13"]{--accent:#ae6348;--wash:#f0dfd4;--soft:#f8ece2}
body.dark[data-chapter]{--wash:#344338;--soft:#28382d;--accent:#d3b17e}
.topbar{background:var(--surface);border-bottom:1px solid var(--line);box-shadow:0 3px 18px #3c2f1d05}.brand img{box-shadow:0 0 0 3px var(--paper),0 0 0 4px #bc965f66}.brand small{color:var(--gold)}
.progress-track{background:var(--line)}.progress-track div{background:linear-gradient(90deg,#6b8066,#b89153,#b66b4d)}
.breadcrumb{letter-spacing:.15px}.hero,.chapter-hero{border-radius:10px;box-shadow:0 12px 36px #362e1710;border:1px solid var(--line);overflow:hidden}.hero{height:505px}.hero-copy{padding-top:65px}.hero h1{font-size:76px;line-height:1.02;letter-spacing:-2.7px}.hero:after{background:linear-gradient(90deg,#122a23ed,#223e2a8a 53%,#182c1d12)}
.topic-hero{grid-template-columns:1fr 39%;min-height:465px}.topic-hero .chapter-copy{padding:48px 45px;background:linear-gradient(135deg,var(--surface),var(--paper))}.topic-hero h1{font-size:54px;line-height:1.09;max-width:17ch}.chapter-hero .meta{gap:12px;flex-wrap:wrap}.chapter-hero .meta span{border:1px solid var(--line);border-radius:30px;padding:7px 12px;background:var(--surface);font-size:10px}
.chapter-question{--art-ground:#f5ecdc;min-height:465px;padding:30px;background:radial-gradient(ellipse at 80% 18%,#fff9 0,transparent 58%),linear-gradient(150deg,var(--soft),var(--wash));color:#273a2e;border-left:1px solid #c6ac814d;justify-content:flex-end;isolation:isolate}
.topic-3 .chapter-question,.topic-7 .chapter-question,.topic-10 .chapter-question,.topic-11 .chapter-question,.topic-12 .chapter-question,.topic-13 .chapter-question{background:radial-gradient(ellipse at 80% 18%,#fff9 0,transparent 58%),linear-gradient(150deg,var(--soft),var(--wash))}
.chapter-question:after{content:'';position:absolute;inset:12px;border:1px solid #a7804f28;border-radius:3px;pointer-events:none;z-index:0}.dark .chapter-question{background:radial-gradient(ellipse at 70% 20%,#f9edd9,#e7d4b4)}
.chapter-art.atlas-art{inset:18px 10px auto;width:calc(100% - 20px);height:265px;color:inherit;z-index:0}.chapter-art.atlas-art:before{display:none}.atlas-art img{width:100%;height:100%;object-fit:contain;filter:drop-shadow(0 10px 9px #6d4d2c1a)}
.chapter-watermark{top:22px;left:22px;font:19px Georgia,serif;color:#705435;z-index:2;border:1px solid #ad8a594d;border-radius:50%;width:38px;height:38px;display:grid;place-items:center;background:#fff9;backdrop-filter:blur(4px)}
.chapter-question .question-copy{padding-top:255px;position:relative;z-index:1}.question-label{color:#775b37;font-size:9px;letter-spacing:1.7px}.chapter-question .question-copy p{font-size:28px;line-height:1.2;margin:14px 0 22px;color:#263c32;max-width:17ch}.question-note{color:#6b705c;font-size:9px;letter-spacing:.5px}.dark .question-label{color:#775b37}.dark .question-note{color:#606952}
.atlas-topics{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:17px;margin:25px 0 45px}.atlas-topics>a{position:relative;overflow:hidden;min-width:0;border:1px solid var(--line);border-radius:8px;background:var(--surface);text-decoration:none;box-shadow:0 4px 14px #4c321a05;transition:transform .18s ease,box-shadow .18s ease}.atlas-topics>a:hover{transform:translateY(-4px);box-shadow:0 12px 24px #4c321a15}.atlas-topics>a:nth-child(2){background:#e7eee5}.atlas-topics>a:nth-child(3){background:#f0e3d0}.atlas-topics>a:nth-child(4){background:#f1e1d6}.dark .atlas-topics>a{background:var(--surface)}.atlas-topics img{display:block;width:100%;height:145px;object-fit:contain;padding:8px 12px 0}.atlas-card-copy{display:block;padding:12px 18px 19px}.atlas-card-copy strong{font:22px/1.2 Georgia,serif;display:block;color:var(--ink)}.atlas-card-copy small{font:11px/1.6 Arial,sans-serif;color:var(--muted);display:block;margin-top:9px}.atlas-card-copy small span{float:right;color:var(--gold)}.atlas-card-number{position:absolute;top:12px;left:13px;font:12px Georgia,serif;border-radius:50%;padding:6px;background:var(--surface);color:var(--gold)}
.article-grid{gap:65px;margin-top:48px}.contents{border:1px solid var(--line);border-radius:8px;padding:21px 16px;background:var(--surface);box-shadow:0 5px 18px #4c321a04}.contents-label{font-size:9px;letter-spacing:1.7px}.contents nav{border:0}.contents nav a{border-radius:5px;margin:2px 0;padding:10px 11px;border-left:2px solid transparent}.contents nav a.active{background:var(--soft);border-left-color:var(--accent);color:var(--ink)}.chapter-nav{margin-top:20px;padding-top:17px}.contents .outline-button{border-radius:5px;border-color:var(--line)}
.reading>section:not(.sources){margin-bottom:55px}.reading>section>h2{padding-bottom:14px;position:relative}.reading>section>h2:after{content:'';position:absolute;bottom:0;left:0;width:46px;height:3px;background:var(--accent);border-radius:4px}.reading .lead{border-left:3px solid var(--accent);padding:17px 22px;background:linear-gradient(90deg,var(--soft),transparent);border-radius:0 7px 7px 0;font-size:22px;line-height:1.7}.intro-label{color:var(--accent)}
.expand{background:var(--surface);border:1px solid var(--line);border-left:3px solid var(--accent);border-radius:6px;padding:17px 20px;box-shadow:0 3px 12px #4c321a03}.expand summary{font-size:13px}.expand summary:after{color:var(--accent)}.expand p{font-size:16px}.expand[open]{background:var(--soft)}
.timeline{padding:8px 0}.timeline:before{left:8px}.timeline-item{gap:25px;padding-bottom:18px;align-items:start}.timeline-item time{padding:13px 10px 10px 0;line-height:1.2;color:var(--accent)}.timeline-item p{padding:17px 20px;border:1px solid var(--line);border-radius:7px;background:var(--surface);font-size:14px;line-height:1.8}.timeline-item:before{top:16px;background:var(--accent)}
.image-figure{background:var(--surface);border:1px solid var(--line);border-radius:8px;padding:12px;box-shadow:0 8px 24px #43321b08}.image-figure .figure-button{border-radius:4px;border:0}.image-figure figcaption{font-size:12px;line-height:1.85;padding:12px 8px 4px}.image-figure figcaption>strong:first-child{font-size:14px;color:var(--ink)}.zoom-label{border-radius:4px}
.quiz{background:var(--soft);padding:27px;border:1px solid var(--line);border-top:3px solid var(--accent);border-radius:8px}.quiz label{background:var(--surface);padding:12px 14px;border:1px solid var(--line);border-radius:5px}.quiz legend{font-size:23px}.quiz button{border-radius:5px}.process{gap:16px}.process>div{padding:19px;background:var(--surface);border:1px solid var(--line);border-radius:7px}
.chapter-pager>a,.chapter-pager>button{border-radius:8px;box-shadow:0 5px 18px #3b2e1c08}.chapter-stepper a{border-radius:5px}.sources{padding-top:30px}.book-sources{border-radius:7px;background:var(--surface);padding:25px;border:1px solid var(--line)}.footer{flex-wrap:wrap}.atlas-credit{flex-basis:100%;font-size:10px;color:var(--muted);border-top:1px solid var(--line);padding-top:15px}
#course-dialog{width:900px;border-radius:10px;padding:30px}.course-list{display:grid;grid-template-columns:1fr 1fr;gap:12px;border:0}.course-list li{border:1px solid var(--line);border-radius:7px;background:var(--surface);overflow:hidden}.course-list a{grid-template-columns:70px 24px 1fr auto;gap:10px;padding:13px 12px;font-size:12px;height:100%}.course-thumbnail{width:70px;height:60px;object-fit:contain;background:var(--soft);border-radius:5px}.course-list a:hover{background:var(--soft)}.lesson-number{font-size:15px}.here{font-size:8px}
@media(min-width:1600px){.hero{height:540px}.hero h1{font-size:82px}.topic-hero .chapter-copy{padding:55px}.topic-hero h1{font-size:60px}.atlas-art img{max-width:470px;display:block;margin:auto}}
@media(max-width:1100px){.article-grid{gap:30px;grid-template-columns:195px minmax(0,1fr)}.topic-hero .chapter-copy{padding:37px 31px}.topic-hero h1{font-size:45px}.chapter-question{padding:27px}.chapter-question .question-copy p{font-size:25px}.atlas-topics{gap:12px}.atlas-card-copy{padding:12px 13px 17px}.atlas-card-copy strong{font-size:19px}.atlas-topics img{height:130px}}
@media(max-width:780px){.hero{height:475px}.hero-copy{padding:46px 30px}.hero h1{font-size:clamp(46px,12vw,65px)}.article-grid{display:block;margin-top:30px}.atlas-topics{grid-template-columns:1fr 1fr;gap:12px;margin:18px 0 28px}.atlas-topics img{height:120px;padding:5px 8px 0}.atlas-card-copy{padding:9px 13px 15px}.atlas-card-copy strong{font-size:20px}.atlas-card-copy small{font-size:10px;margin-top:7px}.topic-hero .chapter-copy{padding:34px 27px}.topic-hero h1{font-size:43px}.chapter-question{min-height:410px;padding:27px;border-left:0;border-top:1px solid #b89a6a33}.chapter-art.atlas-art{height:240px;inset:8px 12px auto;width:calc(100% - 24px)}.chapter-watermark{top:17px;left:18px;font-size:17px;width:35px;height:35px}.chapter-question .question-copy{padding-top:225px}.chapter-question .question-copy p{font-size:28px;max-width:23ch}.reading .lead{padding:15px 18px;font-size:21px}.reading>section>h2{font-size:30px}.timeline-item{padding-left:29px;gap:10px}.timeline-item p{padding:14px 15px}.timeline-item time{padding-bottom:0}.timeline-item:before{top:17px}.image-figure{padding:7px}.image-figure figcaption{padding:10px 4px 3px;font-size:11px}.quiz{padding:20px 17px}.quiz legend{font-size:22px}.book-sources{padding:21px 18px}.course-list{grid-template-columns:1fr}.course-list a{grid-template-columns:65px 23px 1fr auto;font-size:13px}.course-thumbnail{width:65px}.chapter-hero{border-radius:8px}}
@media(max-width:360px){.atlas-card-copy strong{font-size:18px}.atlas-topics img{height:100px}.topic-hero h1{font-size:37px}.chapter-question .question-copy p{font-size:26px}.chapter-art.atlas-art{height:215px}.chapter-question .question-copy{padding-top:205px}.chapter-question{min-height:390px;padding:25px}.hero-copy{padding-left:25px;padding-right:25px}.hero h1{font-size:44px}}
@media(prefers-reduced-motion:reduce){.atlas-topics>a{transition:none}.atlas-topics>a:hover{transform:none}}
@media print{.atlas-topics,.atlas-credit{display:none}.chapter-question{background:white}.reading .lead{background:none}.contents{box-shadow:none}}
#course-dialog{max-width:min(900px,calc(100vw - 32px))}