:root{--primary:#0b3a82;--ink:#102c4c;--muted:#53677e;--line:#dae3ed;--soft:#f3f7fc}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:#fbfdff;font-family:Tahoma,"Segoe UI",Arial,sans-serif;font-size:16px;line-height:1.8}a{color:inherit;text-decoration:none}button,input,select,textarea{font:inherit}button,a,input,select,textarea{outline-offset:4px}img{max-width:100%;display:block}.wrap{width:min(1160px,calc(100% - 40px));margin:auto}.top{background:#fff;border-bottom:1px solid var(--line)}.top .wrap{min-height:84px;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:flex;gap:12px;align-items:center;font-weight:800;font-size:20px}.brand img{width:48px;height:48px;object-fit:contain}.actions{display:flex;gap:10px;flex-wrap:wrap;align-items:center}.btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;border-radius:12px;border:1px solid transparent;padding:10px 21px;font-weight:700;cursor:pointer;line-height:1.5}.primary{background:var(--primary);color:#fff}.light{background:#fff;border-color:var(--line);color:var(--primary)}.outline{border-color:#91b2d1;color:#fff;background:transparent}.btn:hover{filter:brightness(.95)}.hero{background:#082747;color:#fff;padding:70px 0}.hero-grid{display:grid;grid-template-columns:1.3fr .7fr;gap:64px;align-items:center}.eyebrow{font-weight:700;color:#9adbdc;margin-bottom:14px;font-size:15px}.hero h1{font-size:clamp(32px,4.6vw,58px);line-height:1.4;letter-spacing:-1px;margin:0 0 20px}.hero p{font-size:18px;line-height:2;color:#d1deee;max-width:650px}.hero .actions{margin-top:26px}.hero .primary{background:#fff;color:#082747}.teacher-card{border:1px solid #65809b;border-radius:24px;padding:28px;background:rgba(8,39,71,.84)}.teacher-card h2{font-size:24px;margin:12px 0 4px}.teacher-card p{font-size:15px;margin:12px 0}.teacher-card .meta{color:#d1deee}.avatar{width:84px;height:84px;border-radius:20px;overflow:hidden;background:#e4f0fb;color:var(--primary);display:grid;place-items:center;font-size:32px;font-weight:800}.avatar img{width:100%;height:100%;object-fit:cover}.section{padding:48px 0}.section-head{margin-bottom:26px;display:flex;align-items:end;justify-content:space-between;gap:20px}.section-head h2{font-size:30px;margin:0}.meta{font-size:14px;color:var(--muted)}.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.course{border:1px solid var(--line);border-radius:20px;background:#fff;overflow:hidden;display:flex;flex-direction:column}.cover{aspect-ratio:16/9;background:#e7eff8;overflow:hidden;display:grid;place-items:center}.cover img{width:100%;height:100%;object-fit:cover}.cover-label{padding:24px;color:var(--primary);font-size:25px;font-weight:700;line-height:1.7;text-align:center}.course-body{padding:24px;display:flex;flex:1;flex-direction:column}.course h3{margin:8px 0;font-size:22px;line-height:1.6}.price{font-weight:800;font-size:26px;color:var(--primary);margin-top:auto;padding-top:12px}.course .btn{margin-top:16px}.tag{border:1px solid var(--line);border-radius:100px;display:inline-block;padding:3px 12px;font-size:14px;background:var(--soft);width:max-content}.footer{border-top:1px solid var(--line);padding:24px 0;color:var(--muted)}.footer .wrap{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}.card{border:1px solid var(--line);border-radius:20px;padding:28px;background:#fff;margin-bottom:24px}.course-layout{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(300px,.7fr);gap:30px;align-items:start}.course-layout h1{font-size:34px;line-height:1.5;margin:12px 0}.course-layout h2{font-size:24px}.course-layout .cover{border-radius:14px;margin-bottom:20px}.description{white-space:pre-line}.notice,.alert{border:1px solid #a9dac0;background:#f0fff6;color:#185c37;padding:16px;border-radius:12px;margin-bottom:20px}.error{background:#fff3f3;border-color:#f0baba;color:#922b2b}.field{margin-bottom:16px}.field label{display:block;font-weight:700;margin-bottom:5px}.input,select,textarea{width:100%;border:1px solid #b9c9d9;border-radius:10px;padding:11px 13px;background:#fff;color:var(--ink)}.unit{border-bottom:1px solid var(--line);padding:20px 0}.unit:last-child{border:0}.unit summary{cursor:pointer;font-size:18px;font-weight:700}.unit ol{padding-inline-start:24px;color:var(--muted);font-size:15px}.unit-buy{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-top:12px}.pay{padding:16px;background:var(--soft);border-radius:12px;white-space:pre-line;overflow-wrap:anywhere}.empty{padding:32px;border:1px dashed var(--line);border-radius:20px}.small-gap{margin-top:16px}.demo-banner{background:#fff2c4;color:#533f0d;text-align:center;padding:12px;font-weight:700}.only-mobile{display:none}@media(max-width:850px){.hero-grid{grid-template-columns:1fr;gap:30px}.hero{padding:40px 0}.hero h1{max-width:700px}.teacher-card{max-width:600px}.grid{grid-template-columns:repeat(2,minmax(0,1fr))}.course-layout{grid-template-columns:1fr}.section-head{align-items:start}.top .wrap{flex-wrap:wrap;padding:16px 0;gap:12px}.top .actions{gap:8px}.top .btn{min-height:42px;padding:9px 14px}.section{padding:32px 0}}@media(max-width:540px){.wrap{width:calc(100% - 28px)}.brand{font-size:18px}.grid{grid-template-columns:1fr}.section-head{display:block}.card{padding:20px}.hero h1{font-size:36px}.hero p{font-size:16px}.course-layout h1{font-size:28px}.top .actions{width:100%}.top .actions .btn{flex:1}.teacher-card{padding:22px}}

.install-bar{text-align:center;padding:0 20px 24px}.install-modal{display:none;position:fixed;inset:0;background:rgba(8,27,49,.75);z-index:100;align-items:center;justify-content:center;padding:24px}.install-modal.show{display:flex}.install-modal .card{max-width:540px}.install-modal p{white-space:pre-line}