:root{--red:#df252d;--green:#078652;--green2:#0aa069;--ink:#102f27;--muted:#63776f;--line:#c5d9d1;--soft:#f3faf7;--white:#fff;--warn:#fff7e8;--shadow:0 18px 55px rgba(8,70,49,.10)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:#f8fcfa;color:var(--ink);font-family:Arial,Helvetica,sans-serif}.container{width:min(1160px,calc(100% - 36px));margin:auto}.top{background:rgba(248,252,250,.97);border-bottom:1px solid #dce8e3;position:sticky;top:0;z-index:20}.topin{min-height:82px;display:flex;align-items:center;gap:28px}.brand{text-decoration:none;font-weight:900;font-size:27px;letter-spacing:-1.4px;white-space:nowrap}.turbo{color:var(--red)}.uroki{color:var(--green)}.nav{margin-left:auto;display:flex;gap:20px;flex-wrap:wrap}.nav a{text-decoration:none;color:#586d65;font:700 14px ui-monospace,monospace}.nav a:hover,.nav a.active{color:var(--green)}.hero{padding:62px 0 48px;background:linear-gradient(120deg,#fbfdfc,#edf8f3);border-bottom:1px solid #dce8e3}.crumbs{font:13px ui-monospace,monospace;color:#71837c;margin-bottom:22px}.crumbs a{color:var(--green);text-decoration:none}.tag{display:inline-block;padding:7px 11px;background:#e7f5ee;border-left:3px solid var(--green);color:#456c5f;font:13px ui-monospace,monospace}.hero h1{font-size:clamp(40px,6vw,68px);letter-spacing:-2.8px;line-height:1;margin:18px 0}.hero h1 span{color:var(--green)}.hero p{font-size:19px;line-height:1.55;color:#566c64;max-width:850px}.stats{display:flex;gap:10px;flex-wrap:wrap;margin-top:24px}.stat{border:1px solid var(--line);background:white;padding:10px 13px;font:700 13px ui-monospace,monospace}.section{padding:48px 0 76px}.toolbar{display:flex;gap:12px;flex-wrap:wrap;margin-bottom:24px}.toolbar input,.toolbar select{border:1px solid var(--line);background:white;padding:12px 14px;font-size:15px;min-height:44px}.toolbar input{flex:1;min-width:240px}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.card{background:#fff;border:1px solid var(--line);padding:21px;text-decoration:none;color:inherit;min-height:180px;display:flex;flex-direction:column;transition:.18s}.card:hover{transform:translateY(-3px);border-color:var(--green);box-shadow:var(--shadow)}.card .toprow{display:flex;justify-content:space-between;gap:10px;align-items:center;font:700 12px ui-monospace,monospace;color:#789087}.badge{padding:4px 7px;background:#eef7f3;border:1px solid #d1e5dc}.badge.P{background:#fff8e8;border-color:#ecd79b;color:#7b6619}.badge.V{background:#fff0f0;border-color:#efc4c6;color:#9b3036}.card h3{font-size:21px;letter-spacing:-.5px;margin:18px 0 8px}.card p{color:#687b74;line-height:1.45;margin:0 0 18px}.go{margin-top:auto;color:var(--green);font:800 13px ui-monospace,monospace}.notice{margin-top:22px;background:var(--warn);border:1px solid #efd7a5;padding:16px 18px;line-height:1.5}.lesson{padding:46px 0 76px}.lesson-layout{display:grid;grid-template-columns:minmax(0,1fr) 290px;gap:24px}.panel{background:#fff;border:1px solid var(--line);padding:26px;margin-bottom:18px}.panel h2{font-size:27px;letter-spacing:-.8px;margin:0 0 15px}.panel h3{font-size:19px;margin:21px 0 10px}.panel p,.panel li{line-height:1.65;color:#4f665e}.formula{padding:16px 18px;background:#102f27;color:#fff;font:700 17px ui-monospace,monospace;overflow:auto}.steps{counter-reset:s}.steps li{list-style:none;position:relative;padding-left:42px;margin:13px 0}.steps li:before{counter-increment:s;content:counter(s);position:absolute;left:0;top:0;width:27px;height:27px;border:1px solid var(--green);color:var(--green);display:grid;place-items:center;font:800 12px ui-monospace,monospace}.practice{background:#eef8f3;border:1px solid #b8d9ca;padding:20px}.practice input{width:100%;padding:12px;border:1px solid #a9cabc;font-size:16px;margin:10px 0}.btn{border:0;background:var(--green);color:white;padding:12px 16px;font-weight:800;cursor:pointer}.result{font-weight:800;margin-top:10px;min-height:22px}.side{position:sticky;top:104px;align-self:start}.side a{display:block;text-decoration:none;color:#526b61;padding:9px 0;border-bottom:1px solid #e2ece7}.side a:hover{color:var(--green)}.navlesson{display:flex;justify-content:space-between;gap:12px;margin-top:24px}.navlesson a{padding:12px 15px;border:1px solid var(--line);text-decoration:none;color:var(--green);font-weight:800}.footer{border-top:1px solid #dce8e3;padding:30px 0 44px;color:#667871}.footerin{display:flex;justify-content:space-between;gap:20px;align-items:center}@media(max-width:900px){.grid{grid-template-columns:repeat(2,1fr)}.lesson-layout{grid-template-columns:1fr}.side{position:static}.topin{align-items:flex-start;flex-direction:column;padding:16px 0;gap:12px}.nav{margin-left:0}}@media(max-width:580px){.container{width:min(100% - 22px,1160px)}.grid{grid-template-columns:1fr}.hero h1{font-size:42px}.hero p{font-size:17px}.panel{padding:19px}.nav{gap:11px}.footerin{align-items:flex-start;flex-direction:column}}