@font-face{font-family:Golos;src:url('fonts/golos-text/GolosText-Regular.woff2') format('woff2');font-weight:400;font-display:swap}@font-face{font-family:Golos;src:url('fonts/golos-text/GolosText-Medium.woff2') format('woff2');font-weight:500;font-display:swap}@font-face{font-family:Golos;src:url('fonts/golos-text/GolosText-SemiBold.woff2') format('woff2');font-weight:600;font-display:swap}@font-face{font-family:Golos;src:url('fonts/golos-text/GolosText-Bold.woff2') format('woff2');font-weight:700;font-display:swap}
:root{--font-ui:Golos,system-ui,sans-serif;color-scheme:light;--bg:#f5f5f0;--surface:#fff;--soft:#eaf1ec;--text:#242f2b;--muted:#626f68;--line:#dce2da;--accent:#23675c;--accent-hover:#174c42;--focus:#997630;--warn:#7c5324;--warn-bg:#fbf1df;--shadow:0 12px 40px #233d2b08;--radius:20px}
:root[data-theme=dark]{color-scheme:dark;--bg:#171f1d;--surface:#202b27;--soft:#263b33;--text:#e5ede6;--muted:#a7b8af;--line:#3a4b42;--accent:#a0d4bc;--accent-hover:#c6ead7;--focus:#e3bb6a;--warn:#f0ca94;--warn-bg:#3b3021;--shadow:none}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:var(--bg);color:var(--text);font-family:Golos,system-ui,sans-serif;font-size:16px;line-height:1.65}button,input,select,textarea{font:inherit;color:inherit}button,a,input,select,textarea,summary{-webkit-tap-highlight-color:transparent}a{color:var(--accent);text-underline-offset:4px}a:hover{color:var(--accent-hover)}button,.button{border:1px solid var(--line);background:var(--surface);border-radius:12px;padding:10px 16px;cursor:pointer;line-height:1.4;text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:8px;font-weight:500;min-height:44px}button:hover,.button:hover{border-color:var(--accent);color:var(--accent)}button:disabled{opacity:.6;cursor:default}.primary{background:var(--accent);color:var(--surface);border-color:var(--accent)}.primary:hover{background:var(--accent-hover);color:var(--surface)}:focus-visible{outline:3px solid var(--focus);outline-offset:4px}button:focus-visible,a:focus-visible{position:relative;z-index:2}header{min-height:88px;display:flex;align-items:center;gap:32px;padding:18px 36px;border-bottom:1px solid var(--line);background:var(--surface);position:relative;z-index:5}.brand{display:flex;gap:10px;align-items:center;text-decoration:none;color:var(--text);font-size:23px;line-height:1.2;font-weight:600;flex-shrink:0}.brand svg{width:34px;height:34px;stroke:var(--accent);fill:none;stroke-width:2.3;stroke-linecap:round;stroke-linejoin:round}.brand-caption{display:block;font-size:10px;font-weight:400;color:var(--muted);letter-spacing:.03em;margin-top:4px}.subject{color:var(--muted);font-size:14px;text-decoration:none}.header-actions{display:flex;gap:8px;margin-left:auto;align-items:center}.header-actions button{font-size:13px;padding:9px 12px}.layout{max-width:1480px;margin:auto;display:grid;grid-template-columns:208px 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18px}h3{font-size:19px;margin:0 0 12px}p{margin:12px 0}.eyebrow{font-size:11px;font-weight:600;letter-spacing:.13em;text-transform:uppercase;color:var(--accent)}.lead{font-size:18px;color:var(--muted);max-width:670px;line-height:1.65}.hero{position:relative;overflow:hidden;background:var(--soft);border:1px solid var(--line);border-radius:26px;padding:36px;margin-bottom:28px}.hero p,.hero h1,.hero .actions{position:relative;z-index:1}.hero .lead{max-width:560px}.hero-art{position:absolute;width:260px;height:260px;right:-40px;top:30px;opacity:.13;pointer-events:none;color:var(--accent)}.hero-art line,.hero-art path,.hero-art circle{stroke:currentColor;fill:none;stroke-width:1.5}.hero-art circle{fill:var(--soft);stroke-width:3}.actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}.meta{font-size:12px;color:var(--muted);display:flex;gap:12px;flex-wrap:wrap}.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.card{display:block;color:var(--text);background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:23px;text-decoration:none;box-shadow:var(--shadow);min-width:0}.card:hover{color:var(--text);border-color:var(--accent)}.card .week-number{font-size:12px;color:var(--accent);display:block;margin-bottom:19px}.card h3{font-size:20px;line-height:1.3;letter-spacing:-.02em}.card p{font-size:12px;color:var(--muted);line-height:1.6;margin:0}.card .card-meta{font-size:11px;color:var(--muted);margin-top:22px;display:flex;justify-content:space-between;gap:12px}.row{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}.row h2{margin:0}.section-top{margin:34px 0 20px}.pill{background:var(--soft);color:var(--accent);font-size:11px;padding:5px 9px;border-radius:8px;display:inline-block;line-height:1.5}.muted,.small{color:var(--muted)}.small{font-size:13px}.reading{max-width:780px}.reading>p{line-height:1.85}.lesson-list{display:grid;gap:10px;margin:24px 0}.lesson-link{display:flex;gap:16px;align-items:center;padding:18px 22px;background:var(--surface);border:1px solid var(--line);border-radius:15px;text-decoration:none;color:var(--text)}.lesson-link .index{color:var(--accent);font-size:12px;min-width:25px}.lesson-link .link-main{flex:1;min-width:0}.lesson-link strong{font-size:16px;font-weight:500}.lesson-link small{display:block;font-size:11px;color:var(--muted);margin-top:3px}.lesson-link .status{font-size:12px;color:var(--accent)}.lesson-nav{display:flex;gap:12px;flex-wrap:wrap;margin:20px 0 34px}.lesson-nav a{font-size:12px;text-decoration:none}.definition{background:var(--surface);border-left:3px solid var(--accent);padding:22px 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@media(min-width:1500px){.layout{gap:64px}}@media(max-width:1050px){.topic-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.layout{grid-template-columns:175px minmax(0,1fr);gap:26px;padding:26px}header{padding:16px 26px;gap:24px}.hero{padding:28px}.subject{font-size:12px}}@media(max-width:760px){header{padding:15px 18px;gap:10px;flex-wrap:wrap}.brand{font-size:21px}.subject{order:3;flex-basis:100%;font-size:12px;margin-left:44px}.header-actions{gap:5px}.header-actions button{padding:8px 10px}.layout{display:block;padding:0 18px 30px}aside{position:static;margin:0 -18px 25px;border-bottom:1px solid var(--line);padding:10px 12px;background:var(--surface)}nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:4px}nav a{font-size:12px;gap:7px;padding:9px;justify-content:center}nav a span{font-size:16px;width:auto}.aside-note,.side-progress,.back-platform{display:none}.hero{padding:26px 22px;border-radius:20px}.hero-art{right:-100px;top:60px}.hero h1{font-size:32px;max-width:450px}.lead{font-size:16px}.topic-grid{gap:10px}.card{padding:20px}.card h3{font-size:18px}.card .week-number{margin-bottom:14px}.card .card-meta{margin-top:17px;font-size:10px}h2{font-size:24px}.definition,.example,.practice-card,.exam-task{padding:20px}.definition{padding-left:20px}.formula{padding:20px 12px;font-size:14px}.reading>p,.steps li{line-height:1.85}.lesson-link{padding:16px}.lesson-link strong{font-size:14px}.lesson-link .index{min-width:20px}.lesson-link .status{font-size:10px}footer{padding:22px 18px}#notice{padding:14px 18px}.table-wrap{font-size:12px}.row{gap:10px}}@media(max-width:370px){.topic-grid{grid-template-columns:1fr}.hero h1{font-size:30px}.brand-caption{font-size:9px}.header-actions button{font-size:11px;padding:8px}.brand svg{width:29px}nav a{font-size:11px;padding:9px 5px}.card .week-number{margin-bottom:10px}.card .card-meta{margin-top:14px}.card{padding:20px}.layout{padding-left:14px;padding-right:14px}aside{margin-left:-14px;margin-right:-14px}.exam-task{padding:18px}.timer{font-size:20px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
main:focus-visible{outline:none}
@media(max-width:540px){.topic-grid{grid-template-columns:1fr}.topic-grid>a.card{padding:20px 22px}.topic-grid>a.card .week-number{margin-bottom:9px}.topic-grid>a.card h3{font-size:21px;line-height:1.25}.topic-grid>a.card p{display:none}.topic-grid>a.card .card-meta{margin-top:14px;font-size:11px}.hero-art{right:-145px;opacity:.09}}

.formula-line+.formula-line{margin-top:18px}