:root{
    --color-primary:#0345bf; --color-primary-dark:#02328c; --color-bg:#EBF3FE; --color-footer:#1D2027; --color-text:#182033; --color-muted:#6b7280; --color-card:#ffffff; --color-border:#d9e3f4; --radius:18px; --shadow:0 16px 38px rgba(3,69,191,.12); --font-main:'Inter',system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif; --space:22px;
}
*{box-sizing:border-box} body{margin:0;font-family:var(--font-main);background:var(--color-bg);color:var(--color-text)}
a{text-decoration:none;color:inherit}.topbar{background:var(--color-primary);color:#fff;padding:24px 6%;display:flex;justify-content:space-between;align-items:center}.topbar h1{margin:0;font-size:26px;font-weight:800}.topbar p{margin:5px 0 0;opacity:.9}.mainnav{background:#fff;color:var(--color-primary);display:flex;gap:18px;align-items:center;flex-wrap:wrap;padding:12px 6%;box-shadow:0 8px 24px rgba(29,32,39,.08)}.mainnav a{font-weight:700;padding:9px 12px;border-radius:12px}.mainnav a:hover{background:var(--color-bg)}.mainnav span{margin-left:auto;color:var(--color-muted);font-size:14px}.container{width:min(1180px,92%);margin:28px auto 50px}.footer{background:var(--color-footer);color:#fff;text-align:center;padding:18px;margin-top:40px}.hero-card,.section-card,.stat-card,.lesson-card,.video-side,.login-card{background:var(--color-card);border:1px solid var(--color-border);border-radius:var(--radius);box-shadow:var(--shadow)}.hero-card{display:flex;justify-content:space-between;gap:25px;padding:30px;margin-bottom:24px}.hero-card h2{margin:5px 0;font-size:30px}.eyebrow{font-weight:800;text-transform:uppercase;color:var(--color-primary);font-size:12px;letter-spacing:.08em}.hero-stat{min-width:220px;background:var(--color-bg);border-radius:16px;padding:20px}.hero-stat strong,.stat-card strong{display:block;color:var(--color-primary);font-size:26px}.hero-stat span,.stat-card span{color:var(--color-muted)}.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}.stat-card{padding:24px}.section-card{padding:24px;margin-bottom:22px}.section-title h3,.section-card h2{margin-top:0}.section-title p,.topic-block p,.lesson-card p{color:var(--color-muted);line-height:1.55}.topic-block{border-top:1px solid var(--color-border);padding-top:18px;margin-top:18px}.topic-block h4{font-size:20px;margin:0 0 6px}.lesson-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.lesson-card{padding:18px;display:flex;flex-direction:column;gap:8px}.lesson-card h5{font-size:17px;margin:5px 0}.lesson-card.locked{opacity:.78}.badge{display:inline-flex;align-self:flex-start;padding:5px 10px;border-radius:999px;font-size:12px;font-weight:800}.badge.success{background:#dcfce7;color:#166534}.badge.info{background:#dbeafe;color:#1d4ed8}.badge.muted{background:#eef2f7;color:#64748b}.btn{display:inline-flex;align-items:center;justify-content:center;border:none;border-radius:12px;padding:10px 14px;font-weight:800;cursor:pointer;background:#eef2ff;color:var(--color-primary);font-family:var(--font-main)}.btn.primary{background:var(--color-primary);color:#fff}.btn.secondary{background:#fff;color:var(--color-primary);border:1px solid var(--color-border)}.btn.disabled{cursor:not-allowed;background:#e5e7eb;color:#6b7280}.btn.full{width:100%}.btn.tiny{font-size:12px;padding:7px 9px}.danger-link{background:#fee2e2;color:#991b1b}.alert{padding:13px 15px;border-radius:14px;margin:12px 0;font-weight:700}.alert.danger{background:#fee2e2;color:#991b1b}.alert.success{background:#dcfce7;color:#166534}.empty{color:var(--color-muted);background:#f8fafc;border:1px dashed var(--color-border);border-radius:14px;padding:15px}.login-body{min-height:100vh;display:grid;place-items:center;background:linear-gradient(135deg,#EBF3FE,#fff)}.login-card{width:min(440px,92%);padding:34px}.brand-mark{width:68px;height:68px;background:var(--color-primary);color:#fff;border-radius:20px;display:grid;place-items:center;font-weight:900;font-size:24px;margin-bottom:18px}.login-card h1{margin:0;font-size:25px}.login-card p{color:var(--color-muted)}label{font-weight:700;color:#334155;font-size:14px}input,select,textarea{width:100%;border:1px solid var(--color-border);border-radius:12px;padding:12px;margin-top:7px;margin-bottom:13px;font-family:var(--font-main);background:#fff}textarea{min-height:95px;resize:vertical}.form-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px 18px}.span-2{grid-column:span 2}.inline-form{max-width:480px}table{width:100%;border-collapse:collapse;background:#fff}th,td{text-align:left;padding:12px;border-bottom:1px solid var(--color-border);vertical-align:middle}th{font-size:13px;text-transform:uppercase;color:#64748b;background:#f8fafc}.video-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:22px}.video-main{background:#fff;border-radius:var(--radius);padding:24px;border:1px solid var(--color-border);box-shadow:var(--shadow)}.breadcrumb{color:var(--color-primary);font-weight:800;font-size:13px}.video-frame{position:relative;width:100%;padding-top:56.25%;background:#111827;border-radius:18px;overflow:hidden;margin-top:18px}.video-frame iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.video-side{padding:22px;align-self:start}.check-list{display:grid;gap:10px;margin:18px 0}.check-list label{display:grid;grid-template-columns:24px 1fr;gap:8px;background:#f8fafc;border:1px solid var(--color-border);padding:13px;border-radius:14px}.check-list span{grid-column:2;color:var(--color-muted);font-weight:500;font-size:13px}.check-list input{width:auto;margin:3px 0 0}
@media(max-width:900px){.lesson-grid,.stats-grid{grid-template-columns:1fr 1fr}.video-layout,.hero-card{grid-template-columns:1fr;display:grid}.mainnav span{margin-left:0}.form-grid{grid-template-columns:1fr}.span-2{grid-column:span 1}}
@media(max-width:620px){.lesson-grid,.stats-grid{grid-template-columns:1fr}.topbar,.mainnav{padding-left:4%;padding-right:4%}.container{width:94%}}