@import url('https://fonts.googleapis.com/css2?family=Quicksand:wght@500;600;700;800&family=Varela+Round&display=swap');
:root{--class-bg:#f7fbff;--class-surface:#fff;--class-text:#10213f;--class-body:#1f2937;--class-muted:#526173;--class-line:#dce6f2;--class-blue:#2563eb;--class-green:#20c878;--class-green-dark:#0d8f5f;--class-orange:#f59e0b;--class-purple:#7c3aed;--class-soft-blue:#eff6ff;--class-soft-green:#ecfdf5;--class-soft-orange:#fff7ed;--class-soft-purple:#f5f3ff;--class-soft-yellow:#fffbea;--class-focus:#fbbf24;--class-shadow:0 8px 18px rgba(15,23,42,.07);--class-shadow-strong:0 18px 44px rgba(15,23,42,.11);--class-radius:22px}*{box-sizing:border-box}html{scroll-behavior:smooth;overflow-x:hidden}.class-page{min-width:320px;margin:0;overflow-x:hidden;background:linear-gradient(180deg,#fff 0%,var(--class-bg) 48%,#fff 100%);color:var(--class-body);font-family:Quicksand,"Varela Round",Arial,sans-serif;font-size:17px;line-height:1.55;letter-spacing:0}.class-page a{color:inherit}.class-container{width:min(1120px,calc(100% - 32px));margin-inline:auto}.class-header{background:rgba(255,255,255,.97);border-bottom:1px solid var(--class-line);box-shadow:0 6px 18px rgba(15,23,42,.04);backdrop-filter:saturate(1.2) blur(10px);position:sticky;top:0;z-index:30}.class-nav{min-height:76px;display:flex;align-items:center;justify-content:space-between;gap:28px}.class-logo{display:inline-flex;align-items:center;gap:10px;color:#111827;font-size:1.08rem;font-weight:800;text-decoration:none;white-space:nowrap}.class-logo-mark{display:grid;width:38px;height:38px;place-items:center;border-radius:14px;background:var(--class-green);color:#fff;box-shadow:inset 0 -3px 0 rgba(0,0,0,.12),0 8px 18px rgba(32,200,120,.24)}.class-links{display:flex;align-items:center;justify-content:flex-end;gap:16px;min-width:0;overflow-x:auto;scrollbar-width:thin;margin-left:auto}.class-links a{display:inline-flex;min-height:48px;align-items:center;justify-content:center;flex:0 0 auto;border-radius:999px;color:#344154;font-size:16px;font-weight:800;text-decoration:none;white-space:nowrap;padding:0 8px}.class-links a:hover,.class-links .active{color:var(--class-green-dark);background:var(--class-soft-green)}.class-btn{min-height:56px;display:inline-flex;align-items:center;justify-content:center;gap:8px;border-radius:18px;padding:0 24px;border:2px solid transparent;font-size:17px;font-weight:800;line-height:1.2;text-align:center;text-decoration:none;white-space:normal;transition:transform .18s ease,box-shadow .18s ease,background .18s ease,border-color .18s ease,color .18s ease}.class-btn:hover{transform:translateY(-2px);box-shadow:0 12px 24px rgba(15,23,42,.11)}.class-btn:focus-visible,.class-page a:focus-visible{outline:4px solid var(--class-focus);outline-offset:4px}.class-btn.primary{background:var(--class-green);border-color:var(--class-green);color:#fff}.class-btn.primary:hover{background:var(--class-green-dark);border-color:var(--class-green-dark);color:#fff}.class-btn.light,.class-btn.soft{background:#fff;border-color:var(--class-green);color:var(--class-green-dark)}.class-btn.soft{background:var(--class-soft-green)}.class-hero{position:relative;padding-block:54px 48px;overflow:hidden;background:linear-gradient(135deg,#fff 0%,#ecfdf5 46%,#eff6ff 100%);border-bottom:1px solid var(--class-line)}.class-hero:after{content:"";position:absolute;left:0;right:0;bottom:0;height:5px;background:linear-gradient(90deg,var(--class-blue),#ef4444,var(--class-green),var(--class-purple))}.class-breadcrumb{display:flex;flex-wrap:wrap;gap:7px;margin:0 0 14px;color:#64748b;font-size:15px;font-weight:800}.class-breadcrumb a{color:inherit;text-decoration:none}.class-breadcrumb a:hover{color:var(--class-green-dark)}.class-hero-grid{display:grid;grid-template-columns:minmax(0,1fr) 360px;gap:42px;align-items:center}.class-eyebrow{display:inline-flex;min-height:36px;align-items:center;gap:9px;margin:0 0 12px;padding:0 14px;border:1px solid #bbf7d0;border-radius:999px;background:var(--class-soft-green);color:var(--class-green-dark);font-size:14px;font-weight:800}.class-eyebrow:before{content:"";width:9px;height:9px;border-radius:50%;background:var(--class-orange)}.class-hero h1{color:var(--class-text);font-size:clamp(30px,4vw,46px);font-weight:800;line-height:1.08;letter-spacing:0;margin:0 0 14px}.class-lead{max-width:760px;margin:0;color:var(--class-muted);font-size:18px;font-weight:600}.class-actions{display:flex;flex-wrap:wrap;gap:18px 22px;margin-top:24px}.class-stat-card{padding:24px;border:2px solid var(--class-line);border-radius:24px;background:#fff;box-shadow:var(--class-shadow-strong)}.class-stat-card h2{margin:0 0 12px;color:var(--class-text);font-size:1.35rem;font-weight:800}.class-mini-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.class-mini{border:1px solid var(--class-line);border-radius:18px;padding:14px;background:#f8fafc}.class-mini strong{display:block;color:#111827;font-size:1.6rem;font-weight:800;line-height:1.1}.class-mini span{font-size:.92rem;color:var(--class-muted);font-weight:800}.class-stat-section{padding:26px 0 34px;background:#fff;border-bottom:1px solid var(--class-line)}.class-stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}.class-top-stat{display:grid;min-height:100px;align-content:center;text-align:center;padding:18px;border:2px solid var(--class-line);border-radius:22px;background:#fff;box-shadow:var(--class-shadow)}.class-top-stat strong{color:#111827;font-size:32px;font-weight:800;line-height:1}.class-top-stat small{color:#475569;font-weight:800}.class-adventure-map{display:block;margin:24px auto 0;padding:24px 28px;border:2px solid rgba(37,99,235,.16);border-radius:22px;background:linear-gradient(135deg,#fff,var(--class-soft-yellow) 38%,var(--class-soft-blue));box-shadow:var(--class-shadow-strong);color:var(--class-text);font-size:17px;font-weight:800;line-height:1.7;text-align:center}.class-grade-section{padding:18px 0;background:#fff;border-bottom:1px solid var(--class-line)}.class-grade-strip{display:flex;flex-wrap:wrap;gap:12px 18px}.class-grade-strip a{display:inline-flex;min-height:48px;align-items:center;justify-content:center;padding:0 16px;border:2px solid #dbe3ef;border-radius:18px;background:#fff;color:#334155;font-size:16px;font-weight:800;text-decoration:none}.class-grade-strip a.active,.class-grade-strip a:hover{background:var(--class-green);border-color:var(--class-green);color:#fff}.class-section{padding:42px 0;background:#fff}.class-section.white{background:var(--class-bg);border-block:1px solid var(--class-line)}.class-section-head{display:flex;align-items:end;justify-content:space-between;gap:18px;margin-bottom:22px}.class-section-head h2{color:var(--class-text);font-size:clamp(24px,2.4vw,28px);font-weight:800;line-height:1.2;letter-spacing:0;margin:0 0 10px}.class-section-head p{margin:0;color:var(--class-muted);font-weight:700;max-width:760px}.class-guide-cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:22px;margin-bottom:24px}.class-guide-card{display:grid;gap:7px;min-height:118px;padding:18px;border:2px solid var(--class-line);border-radius:22px;background:#fff;box-shadow:var(--class-shadow);text-decoration:none}.class-guide-card span{color:var(--class-green-dark);font-size:.78rem;font-weight:900;text-transform:uppercase}.class-guide-card strong{color:#111827;font-size:1.05rem;font-weight:800}.class-guide-card small{color:var(--class-muted);font-weight:700}.lesson-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:22px}.lesson-card{display:flex;flex-direction:column;min-height:270px;background:linear-gradient(180deg,#fff,#fbfdff);border:2px solid var(--class-line);border-radius:22px;padding:24px;box-shadow:var(--class-shadow);transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease,background .18s ease}.lesson-card:nth-child(4n+1){background:linear-gradient(180deg,#fff,var(--class-soft-blue))}.lesson-card:nth-child(4n+2){background:linear-gradient(180deg,#fff,#fff1f2)}.lesson-card:nth-child(4n+3){background:linear-gradient(180deg,#fff,var(--class-soft-green))}.lesson-card:nth-child(4n+4){background:linear-gradient(180deg,#fff,var(--class-soft-purple))}.lesson-card:hover{transform:translateY(-3px);border-color:var(--class-green);box-shadow:var(--class-shadow-strong)}.lesson-top{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:16px}.lesson-icon{width:56px;height:56px;display:grid;place-items:center;border-radius:18px;background:var(--class-soft-blue);color:var(--class-blue);font-size:1.35rem;font-weight:800;border:1px solid rgba(37,99,235,.12)}.lesson-kind{min-height:34px;display:inline-flex;align-items:center;border-radius:999px;padding:0 12px;background:#fff;border:1px solid var(--class-line);color:#475569;font-size:.82rem;font-weight:900}.lesson-card h3{color:var(--class-text);font-size:20px;font-weight:800;line-height:1.25;margin:0 0 8px}.lesson-card p{margin:0;color:var(--class-muted);font-weight:600}.lesson-tags{display:flex;flex-wrap:wrap;gap:10px;margin:16px 0 0}.lesson-tags span{display:inline-flex;min-height:34px;align-items:center;border:1px solid var(--class-line);background:#fff;border-radius:999px;padding:0 12px;font-size:14px;font-weight:800;color:#344154}.lesson-actions{display:grid;grid-template-columns:1fr;gap:10px;margin-top:auto;padding-top:22px}.class-info-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:22px}.info-panel{background:#fff;border:2px solid var(--class-line);border-radius:22px;padding:24px;box-shadow:var(--class-shadow)}.info-panel h2,.info-panel h3{color:var(--class-text);font-weight:800;margin:0 0 10px}.info-panel p{color:var(--class-muted);font-weight:700;margin:0 0 14px}.info-list{display:grid;gap:10px;margin:0;padding:0;list-style:none}.info-list li{display:flex;gap:10px;align-items:flex-start;border:1px solid var(--class-line);border-radius:16px;padding:12px;background:#f8fafc;font-weight:700}.info-list li:before{content:"";width:10px;height:10px;border-radius:50%;background:var(--class-green);margin-top:7px;flex:0 0 auto}.source-links{display:flex;flex-wrap:wrap;gap:10px}.class-footer{background:#fff;color:var(--class-muted);padding:24px 0;border-top:1px solid var(--class-line);font-weight:800}.class-footer p{margin:8px 0 0}.tier-middle .class-eyebrow:before{background:var(--class-blue)}.tier-middle .lesson-icon{background:#f0fdfa;color:#0f766e}.tier-high.class-page{background:#f8fafc}.tier-high .class-hero{background:linear-gradient(135deg,#111827 0%,#1e293b 70%,#0f172a 100%);color:#fff}.tier-high .class-hero h1{color:#fff}.tier-high .class-lead,.tier-high .class-breadcrumb,.tier-high .class-breadcrumb a{color:#cbd5e1}.tier-high .class-eyebrow{background:rgba(59,130,246,.16);border-color:rgba(147,197,253,.35);color:#bfdbfe}.tier-high .class-stat-card{background:#0f172a;border-color:#334155}.tier-high .class-stat-card h2,.tier-high .class-mini strong{color:#fff}.tier-high .class-mini{background:#111827;border-color:#334155}.tier-high .class-mini span{color:#cbd5e1}.tier-high .class-hero:after{background:linear-gradient(90deg,#38bdf8,#818cf8,#f59e0b)}@media(max-width:1080px){.class-hero-grid,.class-info-grid{grid-template-columns:1fr}.class-guide-cards{grid-template-columns:1fr 1fr}.class-links{gap:12px}.class-stat-grid{grid-template-columns:repeat(2,1fr)}}@media(max-width:760px){.class-container{width:min(100% - 24px,1120px)}.class-page{font-size:16px}.class-nav{align-items:flex-start;flex-direction:column;padding-block:14px;gap:12px}.class-links{width:100%;justify-content:flex-start;margin-left:0;padding-bottom:4px}.class-hero{padding-block:36px}.class-hero h1{font-size:28px}.class-actions,.lesson-actions{display:grid}.class-btn{width:100%}.class-mini-grid,.class-stat-grid,.class-guide-cards,.lesson-grid,.class-info-grid{grid-template-columns:1fr}.class-section-head{display:block}.class-grade-strip{overflow-x:auto;flex-wrap:nowrap;padding-bottom:4px}.class-adventure-map{text-align:left;padding:20px;font-size:16px}}