:root{--ink:#171512;--muted:#6e6962;--line:#dedbd5;--paper:#fbfaf7;--white:#fff;--accent:#8a1538;--soft:#f3f0eb;--sans:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif;--serif:Georgia,"Times New Roman",serif}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font:17px/1.72 var(--serif)}a{color:inherit;text-decoration:none}.wrap{width:min(1280px,calc(100% - 48px));margin:auto}.site-head{border-bottom:1px solid var(--line);background:rgba(251,250,247,.94);position:sticky;top:0;z-index:20;backdrop-filter:blur(10px)}.nav{height:74px;display:flex;align-items:center;justify-content:space-between;font-family:var(--sans)}.brand{display:flex;flex-direction:column;line-height:1.2}.brand span{font-size:12px;color:var(--muted);letter-spacing:.08em;text-transform:uppercase;margin-top:4px}.nav nav{display:flex;gap:28px;font-size:14px}.nav nav a:hover{color:var(--accent)}.hero{padding:110px 0 100px;background:radial-gradient(circle at 80% 20%,rgba(138,21,56,.11),transparent 30%),linear-gradient(180deg,#fff,var(--paper));border-bottom:1px solid var(--line)}.eyebrow,.meta{font:700 12px/1 var(--sans);letter-spacing:.12em;text-transform:uppercase;color:var(--accent)}h1,h2,h3{font-family:var(--serif);font-weight:400;letter-spacing:-.025em}.hero h1,.course-hero h1,.lecture-head h1{font-size:clamp(48px,6vw,84px);line-height:1.03;margin:20px 0}.hero p{max-width:790px;color:var(--muted);font-size:22px}.section{padding:78px 0}.section-title{display:flex;justify-content:space-between;align-items:end;margin-bottom:34px}.section-title h2{font-size:42px;margin:12px 0 0}.section-title>p{font-family:var(--sans);font-size:13px;color:var(--muted)}.course-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}.course-card{background:#fff;border:1px solid var(--line);border-top:4px solid var(--card-accent);transition:.2s}.course-card:hover{transform:translateY(-4px);box-shadow:0 18px 50px rgba(35,25,18,.08)}.course-card img{width:100%;height:190px;object-fit:cover}.course-card-body{padding:28px}.course-card h3{font-size:28px;line-height:1.15;margin:14px 0}.course-card p{color:var(--muted);font-size:16px}.arrow{font:600 14px var(--sans);color:var(--accent)}.empty,.learning-box,.summary-box{padding:28px;border:1px solid var(--line);background:var(--white)}.course-hero,.lecture-head{padding:72px 0;border-bottom:4px solid var(--accent);background:linear-gradient(180deg,#fff,var(--soft))}.split{display:grid;grid-template-columns:1fr 360px;gap:60px;align-items:center}.lead{font-size:22px;color:var(--muted);max-width:800px}.cover{width:100%;aspect-ratio:4/3;object-fit:cover;border-radius:2px;box-shadow:20px 20px 0 rgba(138,21,56,.08)}.chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:28px}.chips span{font:600 12px var(--sans);border:1px solid var(--line);padding:8px 12px;background:#fff}.course-layout{display:grid;grid-template-columns:1fr 330px;gap:70px;padding-top:70px}.course-layout h2,.lecture-body h2{font-size:34px;border-bottom:1px solid var(--line);padding-bottom:12px}.course-layout section{margin-bottom:50px}.course-facts{border-left:3px solid var(--accent);padding:25px 28px;background:#fff;height:max-content}.course-facts h3{font:700 14px var(--sans);text-transform:uppercase;letter-spacing:.08em}.course-facts dt{font:700 11px var(--sans);color:var(--muted);text-transform:uppercase;margin-top:18px}.course-facts dd{margin:4px 0}.check-list li{margin:8px 0}.lecture-list{border-top:1px solid var(--line)}.lecture-list>a{display:grid;grid-template-columns:72px 1fr 30px;gap:22px;align-items:center;border-bottom:1px solid var(--line);padding:24px 8px}.lecture-list>a:hover{background:#fff;padding-left:18px}.module-no{font:500 23px var(--sans);color:var(--accent)}.lecture-list strong{display:block;font-size:22px}.lecture-list small{display:block;color:var(--muted);font:14px var(--sans);margin-top:5px}.back{display:block;font:13px var(--sans);color:var(--muted);margin-bottom:44px}.lecture-head h1{max-width:1000px}.identity{display:flex;gap:50px;border-top:1px solid var(--line);padding-top:22px;margin-top:28px}.identity div{display:flex;flex-direction:column}.identity span{font:700 10px var(--sans);text-transform:uppercase;letter-spacing:.12em;color:var(--muted)}.identity strong{font:500 14px var(--sans);margin-top:5px}.lecture-actions{margin-top:28px}.btn{display:inline-flex;background:var(--accent);color:#fff;padding:12px 18px;font:700 13px var(--sans);border:0;cursor:pointer}.lecture-layout{display:grid;grid-template-columns:260px minmax(0,900px);gap:54px;padding:55px 0 90px}.toc{position:sticky;top:100px;align-self:start;max-height:calc(100vh - 125px);overflow:auto;border-right:1px solid var(--line);padding-right:24px;font-family:var(--sans)}.toc h3{font:700 11px var(--sans);text-transform:uppercase;letter-spacing:.12em;color:var(--muted)}.toc a{display:block;font-size:13px;padding:7px 0;border-bottom:1px solid #ebe8e3}.toc a:hover{color:var(--accent)}.lecture-body section{margin-bottom:54px;scroll-margin-top:105px}.lecture-body h3{font-size:24px}.lecture-body .intro{font-size:22px;color:var(--muted);border-left:3px solid var(--accent);padding-left:22px}.learning-box{background:linear-gradient(135deg,#fff,#f8f3f5)}.learning-box li{margin:8px 0}.section-note,.section-example,.section-exercise,.section-concept{padding:28px;border-left:4px solid var(--accent);background:#fff}.equation{padding:22px;background:#f4f2ee;text-align:center;margin:20px 0;font-size:20px;overflow:auto}.demo-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}.demo-card{padding:24px;background:#fff;border:1px solid var(--line)}.demo-card>span,.resource-list>li>span{font:700 10px var(--sans);text-transform:uppercase;letter-spacing:.1em;color:var(--accent)}.demo-card h3{margin:10px 0}.demo-card p{color:var(--muted);font-size:15px}.demo-card a{font:700 13px var(--sans);color:var(--accent)}.demo-embed{margin-top:18px;overflow:auto}.summary-box{border-top:4px solid var(--accent)}.resource-list{list-style:none;padding:0}.resource-list li{display:grid;grid-template-columns:90px 1fr auto;gap:18px;border-bottom:1px solid var(--line);padding:18px 0}.resource-list p{margin:3px 0;color:var(--muted);font-size:14px}.resource-list a{font:700 12px var(--sans);color:var(--accent)}footer{border-top:1px solid var(--line);padding:35px 0;background:#fff;font-family:var(--sans)}footer .wrap{display:flex;justify-content:space-between;color:var(--muted);font-size:13px}.error-page{padding:130px 0}.error-page h1{font-size:50px}.error-page p{color:var(--muted)}
@media(max-width:900px){.course-grid{grid-template-columns:1fr}.split,.course-layout{grid-template-columns:1fr}.split .cover{max-width:500px}.lecture-layout{display:block}.toc{position:static;border:1px solid var(--line);padding:20px;margin-bottom:35px;max-height:none}.identity{flex-direction:column;gap:14px}.demo-grid{grid-template-columns:1fr}.hero{padding:75px 0}.wrap{width:min(100% - 28px,1280px)}}

/* Rich academic content: images, tables and equations */
.lecture-body img{max-width:100%;height:auto}.lecture-figure{margin:32px auto;text-align:center}.lecture-figure img{display:block;max-width:100%;height:auto;margin:auto;border:1px solid var(--line);background:#fff}.lecture-figure figcaption{max-width:760px;margin:10px auto 0;color:var(--muted);font:13px/1.55 var(--sans)}.table-scroll{width:100%;overflow-x:auto;margin:24px 0}.lecture-table,.lecture-body table{width:100%;border-collapse:collapse;background:#fff;font:14px/1.5 var(--sans)}.lecture-table th,.lecture-table td,.lecture-body table th,.lecture-body table td{border:1px solid var(--line);padding:10px 12px;vertical-align:top}.lecture-table th,.lecture-body table th{background:var(--soft);font-weight:800}.inline-equation{white-space:nowrap}.lecture-body mjx-container{overflow-x:auto;overflow-y:hidden;max-width:100%}