@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Manrope:wght@400;500;600;700;800&display=swap');
:root{--navy:#10192c;--ink:#192337;--muted:#627087;--accent:#12674e;--mint:#5cf0bd;--line:#dde3e9;--paper:#fff;--bg:#f4f7f9}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.75 'DM Sans',sans-serif}header{height:88px;background:var(--navy);color:white;display:flex;align-items:center;justify-content:space-between;padding:0 40px;position:sticky;top:0;z-index:20}.brand{display:flex;align-items:center;gap:22px;color:white;text-decoration:none}.brand img{width:136px;height:54px;object-fit:cover}.brand span{border-left:1px solid #506078;padding-left:22px;font-size:12px;letter-spacing:.18em}header nav{display:flex;gap:32px}header nav a{color:#dce6f2;text-decoration:none;font-size:15px}header nav a:hover{color:var(--mint)}button,input,textarea,select{font:inherit}button,.button{cursor:pointer;border:1px solid var(--line);background:white;border-radius:8px;padding:11px 18px;color:var(--ink);text-decoration:none;display:inline-block;font-weight:600}button:hover,.button:hover{border-color:var(--accent);background:#effaf5}.primary{background:var(--navy);color:white;border-color:var(--navy)}.primary:hover{background:#263b56;color:white}#menu{display:none}.layout{display:grid;grid-template-columns:310px minmax(0,1fr);max-width:1600px;margin:auto}aside{height:calc(100vh - 88px);overflow:auto;position:sticky;top:88px;border-right:1px solid var(--line);background:#fff}.side-head{padding:30px 24px 22px}.eyebrow{font-size:12px;font-weight:800;letter-spacing:.13em;color:var(--accent)}h1,h2,h3,h4{font-family:Manrope,sans-serif;line-height:1.25;letter-spacing:-.025em}h1{font-size:clamp(32px,3.3vw,52px);margin:16px 0 22px}h2{font-size:27px;margin:40px 0 16px}h3{font-size:21px;margin:30px 0 12px}.side-head h2{font-size:25px;margin:8px 0 0}.side-head p{margin:3px 0 20px;color:var(--muted);font-size:14px}input,textarea,select{width:100%;border:1px solid #c6d1dc;border-radius:6px;padding:10px 12px;background:white;color:var(--ink)}textarea{min-height:130px}small{font-size:12px;color:var(--muted)}.progress-text{display:flex;justify-content:space-between;font-size:12px;margin-top:22px}progress{width:100%;height:6px;accent-color:var(--accent);display:block;margin:8px 0}summary{padding:15px 24px;font-size:14px;font-weight:700;cursor:pointer;background:#f8fafb;border-top:1px solid var(--line)}.lesson-link{display:flex;gap:12px;padding:11px 24px;color:#59677a;font-size:14px;line-height:1.45;text-decoration:none;border-left:3px solid transparent}.lesson-link:hover{background:#f1f7f4}.lesson-link.active{background:#eaf7f0;color:#174a3b;border-left-color:var(--accent);font-weight:700}.lesson-link .num{min-width:22px;font-size:12px;opacity:.8}main{padding:52px 6%;min-width:0;max-width:1160px}.breadcrumb{font-size:13px;color:var(--muted);margin-bottom:28px}.intro{font-size:20px;line-height:1.65;color:#536078;max-width:750px}.meta{display:flex;gap:20px;font-size:13px;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:25px;margin:24px 0}.reading{max-width:830px}.reading p{margin:16px 0}.reading li{margin-bottom:10px}.reading a,a{color:var(--accent)}.callout{background:#eaf7f0;border-left:3px solid var(--accent);padding:18px 24px;margin:28px 0;border-radius:0 8px 8px 0}.callout p:first-child{margin-top:0}.callout p:last-child{margin-bottom:0}.dark-box{background:var(--navy);color:#edf3f9;border-radius:14px;padding:26px 30px;margin:28px 0}.dark-box h3{margin-top:0;color:var(--mint)}pre{position:relative;background:#10192c;color:#d4f6e8;padding:24px;border-radius:10px;overflow:auto;font:14px/1.7 Consolas,monospace;white-space:pre-wrap;overflow-wrap:anywhere}code{font: .88em Consolas,monospace;background:#e8eef1;padding:2px 5px;border-radius:3px}pre code{background:none;padding:0;font:inherit}.code-wrap{position:relative}.copy{position:absolute;right:10px;top:10px;padding:4px 9px;font-size:12px;z-index:1}.code-wrap pre{padding-top:48px}table{border-collapse:collapse;width:100%;font-size:15px;display:block;overflow:auto}td,th{padding:13px 16px;border:1px solid var(--line);text-align:left}th{background:#eef4f6}.exercise{border:1px solid var(--line);border-radius:12px;padding:25px;margin:32px 0;background:white}.exercise h3{margin-top:0}.answer{border:0;background:none}.answer summary{background:#eef4f6;border:0;border-radius:6px}.answer p{padding:8px 15px}.lesson-footer{display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;margin:45px 0 20px;padding-top:28px;border-top:1px solid var(--line)}.quiz label{display:block;padding:9px 14px;border:1px solid var(--line);margin:8px 0;border-radius:6px;cursor:pointer}.quiz input{width:auto;margin-right:12px}.result{font-weight:600}.cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.card{border:1px solid var(--line);background:white;padding:24px;border-radius:12px}.card h3{margin:10px 0}.card p{font-size:15px;color:var(--muted)}.flow{display:flex;flex-wrap:wrap;align-items:center;gap:10px;padding:20px 0}.flow span{background:#fff;border:1px solid #bed3c9;border-radius:8px;padding:10px 16px;font-size:14px}.flow b{color:var(--accent)}.lab-output{white-space:pre-wrap;min-height:90px}.tag{font-size:12px;background:#e9f4ef;color:#27634e;padding:5px 9px;border-radius:4px}.author-sign{font-family:Manrope,sans-serif;font-size:28px;font-weight:800}.skip{position:fixed;top:-80px;left:10px;z-index:100;background:white;padding:10px}.skip:focus{top:10px}button:focus-visible,a:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #26a981;outline-offset:3px}.sr-only{position:absolute;clip:rect(0,0,0,0);width:1px;height:1px;overflow:hidden}#toast{position:fixed;bottom:25px;right:25px;background:var(--navy);color:white;padding:12px 20px;border-radius:8px;display:none;z-index:30}hr{border:0;border-top:1px solid var(--line);margin:30px 0}footer{font-size:13px;color:var(--muted);margin-top:35px}@media(max-width:1000px){main{padding:35px 5%}.layout{grid-template-columns:265px minmax(0,1fr)}header{padding:0 24px}}@media(max-width:760px){header{height:74px;padding:0 18px}.brand img{width:108px}.brand span{display:none}header nav{gap:15px}header nav a{font-size:13px}header nav #courseLink{display:none}#menu{display:block;font-size:12px;padding:7px}.layout{display:block}aside{display:none;position:fixed;top:74px;left:0;width:290px;height:calc(100vh - 74px);z-index:19;box-shadow:20px 0 40px #10192c30}aside.open{display:block}main{padding:30px 22px}.intro{font-size:18px}.cards{grid-template-columns:1fr}.meta{gap:12px;flex-wrap:wrap}h1{font-size:34px}body{font-size:16px}.breadcrumb{margin-bottom:18px}}@media print{header,aside,.lesson-footer,.copy,.quiz button{display:none}.layout{display:block}main{max-width:none;padding:0}pre{background:#eee;color:black}.reading{max-width:none}}