:root{--navy:#10243a;--ink:#172637;--gold:#b98c4e;--paper:#f5e8cd;--cream:#fff9eb}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--navy);color:#f8ead2;font:1rem/1.55 Georgia,"Times New Roman",serif}
a{color:inherit}button,input,textarea{font:inherit}button{cursor:pointer}
a:focus-visible,button:focus-visible,input:focus-visible,textarea:focus-visible,summary:focus-visible{outline:3px solid #f1bb5b;outline-offset:4px}
.skip{position:absolute;left:-9999px;top:1rem;z-index:40;background:#fff;color:#111;padding:.8rem}.skip:focus{left:1rem}
.top{min-height:70px;display:flex;align-items:center;justify-content:space-between;gap:1rem;padding:.65rem clamp(1rem,4vw,3rem);border-bottom:1px solid #ffffff29;background:#0b192b}
.brand{display:flex;align-items:center;gap:.7rem;text-decoration:none;font-size:1rem;letter-spacing:.08em;line-height:1.05}
.brand small{display:block;font-size:.68rem;text-transform:uppercase;letter-spacing:.18em;color:#dfc9a7;margin-top:.3rem}
.brand-mark{display:grid;place-items:center;width:40px;height:40px;border:1px solid var(--gold);border-radius:50%;color:#f1c685;font-size:1rem}
.top nav{display:flex;gap:clamp(.6rem,2vw,2rem);align-items:center;flex-wrap:wrap}.top nav a{text-decoration:none;font-size:.95rem;min-height:44px;display:inline-flex;align-items:center}.top nav a:hover{text-decoration:underline;text-underline-offset:.4rem}
main{max-width:1320px;margin:auto;min-height:75vh}
.hero{position:relative;text-align:center;padding:clamp(4.5rem,9vw,8rem) 1rem 9rem;overflow:hidden;background:linear-gradient(90deg,#f7ebd8a8 0%,#ffefcfeb 35%,#ffefcfed 65%,#f7ebd8a8 100%),url('scene.svg') center center/cover no-repeat,#eacda6;color:var(--ink);border-radius:0 0 2rem 2rem}
.hero:before,.hero:after{content:"";position:absolute;pointer-events:none;opacity:.35}
.hero:before{inset:0;background:repeating-linear-gradient(20deg,transparent 0 72px,#42291910 73px 74px),radial-gradient(circle at 5% 75%,var(--accent),transparent 35%),radial-gradient(circle at 95% 18%,#1c4869,transparent 36%);opacity:.15}
.hero:after{content:"";inset:1rem;border:1px solid #79533455;border-radius:1.2rem;opacity:1}
.hero>*{position:relative;z-index:1}.ornament{font-size:2rem;color:var(--accent);margin:0 0 .8rem}.kicker{text-transform:uppercase;letter-spacing:.22em;font:700 .75rem/1.5 system-ui,sans-serif;color:var(--accent)}
h1,h2,h3,h4,p{margin-top:0}.hero h1{max-width:980px;margin:.35rem auto;font-size:clamp(3.7rem,10vw,8.2rem);line-height:.95;font-weight:400;letter-spacing:-.055em;text-wrap:balance}.hero h1 em{display:block;color:var(--accent);font-style:normal}
.hero .lead{max-width:570px;margin:1.3rem auto 2.2rem;font-size:clamp(1.05rem,2vw,1.35rem);line-height:1.5}.cta{display:inline-flex;align-items:center;justify-content:center;gap:.7rem;padding:.8rem 1.5rem;min-height:48px;background:var(--accent);color:#fff;border:1px solid #ffffff4d;border-radius:.45rem;text-decoration:none;box-shadow:0 12px 24px #1116;font-weight:700}
.cta:hover{filter:brightness(1.12)}.hero-mark{position:absolute;bottom:4.4rem;left:50%;transform:translateX(-50%);z-index:1;color:var(--accent);font-size:2.5rem}
.shell{padding:1.4rem clamp(1rem,4vw,3rem) 4rem}.section-head{display:flex;align-items:end;justify-content:space-between;gap:1rem;margin:1.3rem 0}.section-head h2{font-size:clamp(1.8rem,3vw,2.8rem);font-weight:400;margin:.2rem 0}.eyebrow{font:700 .72rem/1.4 system-ui,sans-serif;letter-spacing:.18em;text-transform:uppercase;color:#dcb775}
.cover-shell{position:relative;margin-top:-4.2rem}.concept-gallery{position:relative;display:grid;grid-template-columns:180px minmax(0,1fr);gap:1rem;padding:1.15rem;border:1px solid #c29a60;border-radius:.6rem;background:#10243a;box-shadow:0 20px 45px #060e1880;margin-bottom:2.4rem}.concept-heading{padding:.3rem .6rem;color:#f7e4c0}.concept-heading .ornament{font-size:1.55rem;color:#d3a867}.concept-heading h2{font-size:1.5rem;line-height:1.08;font-weight:400;margin:.3rem 0}.concept-heading p{font-size:.83rem;color:#e7d4b3;margin:0}.concept-grid{display:grid;grid-template-columns:repeat(9,minmax(0,1fr));gap:.5rem}.concept{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;min-height:128px;gap:.35rem;background:#f2e2c4;color:#172637;border:1px solid #bf9a66;border-radius:60px 60px 9px 9px;padding:.5rem .2rem;text-decoration:none}.concept:nth-child(2n){background:#f8edd7}.concept:hover,.concept:focus-visible{background:#fff7e8;transform:translateY(-3px)}.concept-symbol{display:grid;place-items:center;width:48px;height:48px;border:1px solid #a67648;border-radius:50%;font-size:1.18rem;font-weight:700;color:var(--accent)}.concept-name{font-size:.75rem;line-height:1.1;overflow-wrap:anywhere}.concept-number{font:.62rem system-ui,sans-serif;color:#70604f}
.number-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(205px,1fr));gap:.8rem}
.chapter-card{position:relative;display:flex;flex-direction:column;min-height:250px;border:1px solid #c69359;padding:1.1rem 1.3rem;background:var(--paper);color:var(--ink);border-radius:.55rem;text-decoration:none;box-shadow:0 12px 25px #0003}
.chapter-card:hover{transform:translateY(-3px)}.chapter-card .num{display:grid;place-items:center;width:37px;height:37px;background:var(--navy);color:#fff;border-radius:50%;font:700 .9rem system-ui,sans-serif}.chapter-card h3{font-size:1.55rem;line-height:1.07;margin:auto 0 .6rem}.chapter-card p{font-size:.94rem;line-height:1.3;margin:0 0 1rem}.chapter-card .arrow{align-self:flex-end;color:var(--accent);font-size:1.5rem}
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:.8rem;margin-top:1rem}.feature{display:flex;flex-direction:column;min-height:200px;padding:1.5rem;border:1px solid #b58a56;border-radius:.5rem;background:#1a3046;text-decoration:none}.feature:nth-child(2){background:var(--paper);color:var(--ink)}.feature:nth-child(3){background:var(--accent)}.feature strong{font-size:1.7rem;font-weight:400;line-height:1.1}.feature span:last-child{margin-top:auto;text-align:right;font-size:1.7rem}.feature p{max-width:30ch;margin:1rem 0}
.page-title{padding:clamp(2.5rem,6vw,5rem) 1.3rem;background:radial-gradient(circle at 90% 0,#d8bb8766,transparent 35%),var(--paper);color:var(--ink);border-radius:0 0 1.5rem 1.5rem}.page-title .inner{max-width:1000px;margin:auto}.page-title h1{font-size:clamp(2.6rem,7vw,5rem);line-height:1.03;font-weight:400;max-width:15ch}.page-title p{max-width:60ch;font-size:1.18rem}.page-title .eyebrow{color:var(--accent)}
.content-layout{display:grid;grid-template-columns:minmax(0,240px) minmax(0,760px);gap:clamp(1rem,4vw,4rem);justify-content:center;padding:2rem 1rem 4rem}
.side{align-self:start;position:sticky;top:1rem;border-left:1px solid var(--gold);padding-left:1rem;font-size:.9rem}.side a{display:block;padding:.3rem 0;text-decoration:none}.side a:hover{text-decoration:underline}.side strong{display:block;color:#e5bd80;margin-bottom:.7rem}
.prose{background:var(--cream);color:var(--ink);padding:clamp(1.3rem,4vw,3rem);border-radius:.6rem;min-width:0;box-shadow:0 24px 70px #0003}.prose h2{font-weight:400;font-size:2rem;margin:2.5rem 0 .7rem}.prose h3{font-size:1.45rem;margin:1.6rem 0 .5rem}.prose h4{font-size:1.14rem;margin:1.6rem 0 .5rem;color:var(--accent)}.prose p{line-height:1.7;max-width:68ch}.prose .question{border-left:4px solid var(--accent);padding:1rem 1.2rem;background:#f0e0bf;font-size:1.18rem}
.source{margin:1.2rem 0;border:1px solid #d2bd9d;border-radius:.45rem;scroll-margin-top:1rem}.source summary{cursor:pointer;padding:1rem 1.1rem;font-weight:700;background:#f2e5ce}.source summary:hover{background:#e9d7b9}.source .source-body{padding:1.3rem}.source .source-body p{margin-bottom:1rem}.source .source-body p:first-child{font-weight:700}.source a{color:#783b28}
.source-check{border-top:1px solid #d2bd9d;margin-top:1.5rem;padding-top:1rem}.source-check a{display:inline-flex;align-items:center;min-height:44px;font-weight:700}
.practice{margin:2rem 0;padding:1.5rem;border-radius:.5rem;background:#e9d7b7}.practice label{display:block;margin-bottom:.6rem}.practice textarea{display:block;width:100%;min-height:100px;border:1px solid #72624d;background:#fffefa;padding:.8rem}.practice small{display:block;margin-top:.5rem}
.actions{display:flex;gap:.8rem;flex-wrap:wrap;margin:1.5rem 0}.actions a,.actions button{padding:.7rem 1rem;min-height:44px;border-radius:.25rem;background:var(--navy);color:white;border:0;text-decoration:none;display:inline-flex;align-items:center}.actions .secondary{background:transparent;color:var(--accent);border:1px solid var(--accent)}
.map-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:1rem}.map-group{border:1px solid #c79c65;padding:1.3rem;border-radius:.45rem;background:var(--cream);color:var(--ink)}.map-group h2{font-weight:400;color:var(--accent)}.map-group a{display:block;padding:.55rem 0;color:#17415d}.map-group p{font-size:.95rem}.map-group .key{font-size:2rem;color:var(--accent);line-height:1}
.diagram{max-width:900px;margin:1rem auto 2rem;text-align:center}.diagram-center{display:inline-grid;place-items:center;min-width:220px;min-height:100px;border:2px solid var(--gold);border-radius:50%;padding:1rem 1.5rem;background:var(--paper);color:var(--ink);font-size:1.7rem;line-height:1.15}.diagram-center span{display:block;font-size:.95rem}.diagram-branches{position:relative;display:grid;grid-template-columns:1fr 1fr;gap:1.5rem;padding-top:2rem}.diagram-branches:before{content:"";position:absolute;top:0;left:50%;height:2rem;border-left:2px solid var(--gold)}.diagram-branches section{position:relative;padding:1.25rem;background:#f7e8ca;color:var(--ink);border:1px solid var(--gold);border-radius:.5rem}.diagram-branches section:before{content:"";position:absolute;left:50%;top:-2rem;height:2rem;border-left:2px solid var(--gold)}.diagram-branches strong{display:block;color:var(--accent);font-size:1.3rem}.diagram-branches p{margin:.3rem}.diagram-branches a{display:inline-flex;margin:.35rem;padding:.4rem .7rem;border:1px solid #9a7959;border-radius:1rem;min-height:44px;align-items:center;text-decoration:none}.diagram-branches a:hover{background:#e2cda9}
.quiz{max-width:850px;margin:2rem auto 4rem;padding:1rem}.quiz .q-card{border:1px solid #b69463;border-radius:.5rem;padding:1.3rem;margin:1rem 0;background:var(--cream);color:var(--ink)}.q-card legend{font-weight:700;font-size:1.12rem;padding:.3rem .2rem}.q-card label{display:flex;align-items:start;gap:.75rem;padding:.6rem .35rem;cursor:pointer;min-height:44px}.q-card label:hover{background:#f2e6d3}.q-card input{margin-top:.4rem;accent-color:var(--accent)}
.result{background:var(--paper);color:var(--ink);padding:2rem;margin:1.5rem 0;border-radius:.5rem}.result h2{font-size:2.4rem;font-weight:400}.result .error{border-top:1px solid #ae9675;padding:1rem 0}.result .error a{color:#703428;font-weight:700}
footer{display:flex;justify-content:space-between;gap:1rem;flex-wrap:wrap;border-top:1px solid #ffffff3d;padding:1.5rem clamp(1rem,4vw,3rem);font-size:.82rem;color:#e8d5b5}
@media(max-width:1100px){.concept-gallery{display:block}.concept-heading{margin-bottom:1rem}.concept-heading h2{display:inline;margin-right:1rem}.concept-grid{grid-template-columns:repeat(5,1fr)}}
@media(max-width:800px){.top{align-items:flex-start;flex-direction:column}.top nav{width:100%;justify-content:space-between}.content-layout{display:block}.side{position:static;display:flex;flex-wrap:wrap;gap:1rem;margin-bottom:1rem}.side a{display:inline-block}.feature-grid{grid-template-columns:1fr}.feature{min-height:150px}.diagram-branches{grid-template-columns:1fr;gap:2rem}.hero{background-position:center center,left center}.concept-grid{grid-template-columns:repeat(3,1fr)}}
@media(max-width:480px){.top nav{gap:.1rem}.top nav a{font-size:.78rem}.hero{padding-bottom:7rem}.hero-mark{bottom:2rem}.number-grid{grid-template-columns:1fr}.chapter-card{min-height:200px}.concept-gallery{padding:.75rem}.concept{min-height:105px}.concept-symbol{width:40px;height:40px}.concept-name{font-size:.69rem}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.chapter-card:hover{transform:none}}
@media print{.top,.side,.actions,.practice textarea,footer{display:none!important}body{background:white;color:black}.content-layout{display:block;padding:0}.prose{box-shadow:none;padding:0}.source{break-inside:avoid}.source .source-body{display:block}}