:root{
  --bg:#f4f7f9;--surface:#fff;--surface2:#f8fbfc;--text:#131821;--muted:#687180;
  --line:#e4eaee;--brand:#0B5FFF;--brand2:#5B9DFF;--dark:#060F22;--warning:#f6a723;
  --radius:22px;--shadow:0 18px 55px rgba(17,38,48,.08);
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",Arial,sans-serif;background:var(--bg);color:var(--text)}
a{text-decoration:none;color:inherit}button,input,select,textarea{font:inherit}.app{min-height:100vh;display:grid;grid-template-columns:238px 1fr;gap:16px;padding:16px}
.sidebar{position:sticky;top:16px;height:calc(100vh - 32px);background:rgba(255,255,255,.88);backdrop-filter:blur(22px);border:1px solid rgba(255,255,255,.8);border-radius:28px;padding:24px 18px;box-shadow:var(--shadow);display:flex;flex-direction:column}
.logo{width:142px;margin:4px 10px 30px}.nav{display:grid;gap:7px}.nav a{display:flex;align-items:center;gap:12px;padding:13px 14px;border-radius:15px;color:#4e5866;font-weight:600;font-size:14px}.nav a:hover,.nav a.active{background:linear-gradient(90deg,rgba(11,95,255,.14),rgba(91,157,255,.12));color:#0A4FE0}.nav .ico{font-size:18px;width:22px;text-align:center}.sidebar-bottom{margin-top:auto;border-top:1px solid var(--line);padding-top:18px}.profile-mini{display:flex;align-items:center;gap:11px}.avatar{width:42px;height:42px;border-radius:50%;background:linear-gradient(135deg,var(--brand),#063BC2);color:white;display:grid;place-items:center;font-weight:800}.main{min-width:0}.topbar{height:72px;background:rgba(255,255,255,.78);backdrop-filter:blur(20px);border:1px solid rgba(255,255,255,.9);border-radius:24px;display:flex;align-items:center;justify-content:space-between;padding:0 24px;margin-bottom:16px}.search{display:flex;align-items:center;gap:10px;background:white;border:1px solid var(--line);border-radius:16px;padding:12px 16px;min-width:360px;color:var(--muted)}.search input{border:0;outline:0;width:100%;background:transparent}.top-actions{display:flex;align-items:center;gap:12px}.pill{border:1px solid var(--line);background:white;border-radius:999px;padding:10px 14px;font-weight:650}.content{background:rgba(255,255,255,.74);border:1px solid rgba(255,255,255,.9);border-radius:28px;box-shadow:var(--shadow);padding:24px}
.hero{min-height:370px;border-radius:26px;overflow:hidden;position:relative;background:linear-gradient(90deg,#081226 0%,rgba(8,18,38,.82) 38%,rgba(8,18,38,.05) 75%),url('../assets/hero-home.jpg') center/cover}.hero .copy{position:absolute;left:54px;top:54px;color:white;max-width:560px}.eyebrow{letter-spacing:.28em;text-transform:uppercase;font-size:12px;color:var(--brand2);font-weight:800}.hero h1{font-size:54px;line-height:1.02;margin:20px 0 15px}.hero p{font-size:18px;line-height:1.55;color:#d8e2e3}.btn{border:0;border-radius:14px;padding:14px 20px;font-weight:750;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;gap:9px}.btn-primary{color:white;background:linear-gradient(135deg,var(--brand),#0847D6);box-shadow:0 10px 26px rgba(11,95,255,.28)}.btn-secondary{background:white;border:1px solid var(--line)}.btn-ghost{background:transparent;border:1px solid rgba(255,255,255,.35);color:white}.section{margin-top:24px}.section-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px}.section h2{font-size:23px;margin:0}.grid{display:grid;gap:16px}.grid-4{grid-template-columns:repeat(4,1fr)}.grid-3{grid-template-columns:repeat(3,1fr)}.card{background:white;border:1px solid var(--line);border-radius:20px;overflow:hidden;box-shadow:0 10px 28px rgba(17,38,48,.05)}.card-body{padding:16px}.course-card img{width:100%;height:165px;object-fit:cover}.tag{display:inline-flex;padding:5px 9px;border-radius:999px;background:#E8F0FF;color:#0A4FE0;font-size:12px;font-weight:800}.course-card h3{font-size:17px;margin:11px 0 7px}.muted{color:var(--muted)}.progress{height:6px;background:#e9eef1;border-radius:99px;overflow:hidden}.progress span{display:block;height:100%;background:linear-gradient(90deg,var(--brand),var(--brand2));border-radius:99px}.stat-row{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}.stat{background:white;border:1px solid var(--line);border-radius:18px;padding:18px;display:flex;gap:13px;align-items:center}.stat b{font-size:22px}.glass{background:linear-gradient(135deg,rgba(255,255,255,.95),rgba(235,242,255,.75));border:1px solid rgba(255,255,255,.9);box-shadow:var(--shadow)}
.page-title{display:flex;align-items:end;justify-content:space-between;margin-bottom:22px}.page-title h1{font-size:34px;margin:0 0 7px}.layout-2{display:grid;grid-template-columns:minmax(0,1fr) 360px;gap:18px}.panel{background:white;border:1px solid var(--line);border-radius:22px;padding:20px}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}.field{display:grid;gap:7px}.field label{font-size:13px;font-weight:700}.field input,.field select,.field textarea{border:1px solid var(--line);border-radius:13px;padding:13px 14px;outline:0;background:#fff}.field input:focus,.field textarea:focus{border-color:var(--brand);box-shadow:0 0 0 3px rgba(11,95,255,.10)}
.tabs{display:flex;gap:8px;border-bottom:1px solid var(--line);margin-bottom:16px}.tab{padding:12px 14px;border-bottom:2px solid transparent;font-weight:700;color:var(--muted)}.tab.active{color:var(--brand);border-color:var(--brand)}
.video{aspect-ratio:16/9;border-radius:22px;background:linear-gradient(90deg,rgba(5,12,26,.74),rgba(5,12,26,.15)),url('../assets/hero-course.jpg') center/cover;position:relative;color:white;overflow:hidden}.video-copy{position:absolute;left:38px;bottom:42px}.play{width:64px;height:64px;border-radius:50%;background:white;color:var(--dark);display:grid;place-items:center;font-size:25px}.lesson-list{display:grid;gap:8px}.lesson{padding:12px;border:1px solid var(--line);border-radius:14px;display:grid;grid-template-columns:44px 1fr auto;gap:10px;align-items:center}.lesson.active{border-color:var(--brand);background:#EEF4FF}.lesson-list .lesson{cursor:pointer;transition:border-color .15s,background .15s}.lesson-list .lesson:hover{border-color:var(--brand)}
.quiz-option{display:flex;align-items:center;gap:14px;border:1px solid var(--line);border-radius:16px;padding:17px;margin:10px 0;cursor:pointer}.quiz-option.selected{border-color:var(--brand);background:#EEF4FF}.letter{width:32px;height:32px;border-radius:50%;border:1px solid var(--line);display:grid;place-items:center;font-weight:800}.selected .letter{background:var(--brand);color:white;border-color:var(--brand)}
.chat{height:650px;display:flex;flex-direction:column}.messages{flex:1;overflow:auto;padding:10px 4px;display:flex;flex-direction:column;gap:12px}.bubble{max-width:74%;padding:14px 16px;border-radius:18px;line-height:1.5}.bubble.ai{align-self:flex-start;background:#f1f5f6}.bubble.user{align-self:flex-end;background:#DFE9FF}.composer{display:flex;gap:10px;border:1px solid var(--line);padding:10px;border-radius:16px}.composer input{flex:1;border:0;outline:0}.article{display:flex;gap:12px;padding:14px;border:1px solid var(--line);border-radius:14px;margin-bottom:10px}.article .doc{width:42px;height:42px;border-radius:12px;background:#E8F0FF;display:grid;place-items:center}
.checkout-steps{display:flex;align-items:center;gap:14px;margin:20px 0}.step{display:flex;align-items:center;gap:8px}.step i{width:30px;height:30px;border-radius:50%;border:1px solid var(--line);display:grid;place-items:center;font-style:normal}.step.active i,.step.done i{background:var(--brand);color:white;border-color:var(--brand)}.step-line{height:1px;background:var(--line);width:100px}.pay-methods{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.pay-method{padding:18px;border:1px solid var(--line);border-radius:16px;cursor:pointer}.pay-method.active{border-color:var(--brand);background:#EEF4FF}.summary-line{display:flex;justify-content:space-between;padding:10px 0;border-bottom:1px solid var(--line)}
.auth{min-height:100vh;display:grid;grid-template-columns:1.05fr .95fr;background:white}.auth-art{background:linear-gradient(135deg,#061024,#0A2350);color:white;padding:60px;position:relative;overflow:hidden}.auth-art:after{content:"";position:absolute;inset:20% -15% -15% 30%;background:radial-gradient(circle at 50% 50%,rgba(11,95,255,.35),transparent 55%)}.auth-form{display:grid;place-items:center;padding:40px}.auth-box{width:min(520px,100%);padding:40px;border:1px solid var(--line);border-radius:26px;box-shadow:var(--shadow)}
.landing{background:white}.landing nav{height:78px;display:flex;align-items:center;justify-content:space-between;max-width:1320px;margin:auto;padding:0 24px}.landing-hero{background:linear-gradient(90deg,#05101F 0%,#0A1E3A 48%,rgba(0,0,0,.05)),url('../assets/hero-course.jpg') center/cover;color:white;min-height:660px}.landing-hero .inner{max-width:1320px;margin:auto;padding:130px 24px}.landing-hero h1{font-size:65px;max-width:690px;line-height:1.02;margin:18px 0}.landing-section{max-width:1320px;margin:auto;padding:80px 24px}.feature-band{background:#081226;color:white}.rank{font-size:72px;line-height:1;-webkit-text-stroke:2px white;color:transparent;margin-right:-15px;z-index:2}
.event-card{padding:18px;display:grid;grid-template-columns:70px 1fr auto;gap:16px;align-items:center}.date-box{background:#EAF1FF;color:var(--brand);border-radius:14px;padding:12px;text-align:center;font-weight:800}
.faq-item{border-bottom:1px solid var(--line);padding:18px 0}.faq-q{display:flex;justify-content:space-between;font-weight:750;cursor:pointer}.faq-a{display:none;color:var(--muted);line-height:1.6;padding-top:10px}.faq-item.open .faq-a{display:block}
.toast{position:fixed;right:24px;bottom:24px;background:#0B1A2E;color:white;padding:14px 18px;border-radius:14px;box-shadow:var(--shadow);display:none;z-index:50}
@media(max-width:1100px){.app{grid-template-columns:88px 1fr}.sidebar{padding:20px 10px}.logo{width:65px;margin:5px auto 24px}.nav a span:not(.ico),.profile-mini>div:last-child{display:none}.nav a{justify-content:center}.grid-4{grid-template-columns:repeat(2,1fr)}.layout-2{grid-template-columns:1fr}.search{min-width:260px}}
@media(max-width:760px){.app{display:block;padding:8px}.sidebar{position:fixed;bottom:8px;left:8px;right:8px;top:auto;height:70px;z-index:20;flex-direction:row;padding:8px 10px}.logo,.sidebar-bottom,.nav a:nth-child(n+6){display:none}.nav{display:flex;width:100%;justify-content:space-around}.nav a{padding:9px}.topbar{height:auto;padding:12px;gap:10px}.search{min-width:0;flex:1}.top-actions .pill{display:none}.content{padding:16px;margin-bottom:78px}.hero{min-height:490px}.hero .copy{left:25px;top:35px;right:25px}.hero h1{font-size:40px}.grid-4,.grid-3,.stat-row,.form-grid,.pay-methods{grid-template-columns:1fr}.layout-2{display:block}.layout-2>*{margin-bottom:14px}.auth{grid-template-columns:1fr}.auth-art{display:none}.landing nav .navlinks{display:none}.landing-hero h1{font-size:44px}.landing-section{padding:50px 18px}}