:root{--navy-950:#0a1228;--navy-900:#0e1a38;--navy-800:#16244c;--navy-700:#1f3263;--navy-100:#dde4f2;--accent:#3b82f6;--accent-hover:#2563eb;--white:#fff;--gray-50:#f6f8fb;--gray-100:#eef1f6;--gray-200:#dfe4ec;--gray-500:#64748b;--gray-700:#334155;--error:#b91c1c;--error-bg:#fee2e2;--radius-lg:16px;--radius-md:12px;--shadow-card:0 1px 2px #0a12280f, 0 8px 24px #0a122814}*{box-sizing:border-box;margin:0;padding:0}html{-webkit-text-size-adjust:100%}body{background:var(--gray-50);color:var(--gray-700);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;line-height:1.6}.page{flex-direction:column;min-height:100vh;display:flex}.topbar{background:var(--navy-950);border-bottom:1px solid #ffffff14}.topbar-inner{justify-content:space-between;align-items:center;max-width:1160px;margin:0 auto;padding:16px 24px;display:flex}.brand{align-items:center;gap:12px;display:flex}.brand-mark{background:linear-gradient(135deg, var(--accent), #1d4ed8);width:36px;height:36px;color:var(--white);letter-spacing:.02em;border-radius:8px;justify-content:center;align-items:center;font-size:.85rem;font-weight:700;display:inline-flex}.brand-name{color:var(--white);letter-spacing:.01em;font-size:1rem;font-weight:600}.poc-badge{color:var(--navy-100);letter-spacing:.06em;text-transform:uppercase;background:#ffffff14;border:1px solid #ffffff29;border-radius:999px;padding:4px 14px;font-size:.75rem;font-weight:600}.main{flex:1;width:100%}.hero{background:linear-gradient(180deg, var(--navy-950) 0%, var(--navy-900) 100%);color:var(--white);text-align:center;padding:64px 24px 120px}.hero-eyebrow{color:#93b4f5;letter-spacing:.14em;text-transform:uppercase;margin-bottom:14px;font-size:.8rem;font-weight:700}.hero-title{letter-spacing:-.02em;max-width:760px;margin:0 auto 16px;font-size:clamp(1.9rem,4vw,2.8rem);font-weight:700;line-height:1.15}.hero-subtitle{color:var(--navy-100);max-width:640px;margin:0 auto;font-size:1.08rem}.overview-card{background:var(--white);border:1px solid var(--gray-200);border-radius:var(--radius-lg);max-width:1160px;box-shadow:var(--shadow-card);width:calc(100% - 48px);margin:-72px auto 0;padding:28px 32px}.overview-grid{grid-template-columns:repeat(4,1fr);gap:24px;display:grid}.overview-item{flex-direction:column;gap:4px;display:flex}.overview-label{letter-spacing:.1em;text-transform:uppercase;color:var(--gray-500);font-size:.72rem;font-weight:700}.overview-value{color:var(--navy-900);font-size:.95rem;font-weight:600}.disclaimer{background:var(--gray-100);border-left:3px solid var(--gray-500);color:var(--gray-700);border-radius:6px;margin-top:22px;padding:12px 16px;font-size:.85rem}.classroom{grid-template-columns:minmax(0,2.1fr) minmax(280px,1fr);align-items:start;gap:24px;max-width:1160px;margin:32px auto 56px;padding:0 24px;display:grid}.video-card{background:var(--navy-900);border-radius:var(--radius-lg);box-shadow:var(--shadow-card);aspect-ratio:16/10;flex-direction:column;min-height:420px;display:flex;overflow:hidden}.video-frame-wrap{flex:1;min-height:0;position:relative}.video-frame{border:0;width:100%;height:100%;position:absolute;inset:0}.video-toolbar{background:var(--navy-950);border-top:1px solid #ffffff14;justify-content:space-between;align-items:center;gap:16px;padding:12px 18px;display:flex}.live-indicator{color:var(--navy-100);align-items:center;gap:8px;font-size:.85rem;font-weight:500;display:inline-flex}.live-dot{background:#ef4444;border-radius:50%;width:8px;height:8px;animation:1.6s ease-in-out infinite pulse}@keyframes pulse{0%,to{opacity:1}50%{opacity:.35}}.end-button{appearance:none;cursor:pointer;color:var(--white);background:0 0;border:1px solid #ffffff4d;border-radius:8px;padding:8px 20px;font-size:.88rem;font-weight:600;transition:background-color .15s,border-color .15s}.end-button:hover{background:#dc2626;border-color:#dc2626}.video-placeholder{text-align:center;color:var(--navy-100);flex-direction:column;flex:1;justify-content:center;align-items:center;padding:40px 32px;display:flex}.placeholder-icon{color:#7fa8f0;background:#3b82f629;border-radius:50%;justify-content:center;align-items:center;width:64px;height:64px;margin-bottom:20px;display:inline-flex}.placeholder-title{color:var(--white);margin-bottom:8px;font-size:1.35rem;font-weight:600}.placeholder-text{max-width:420px;margin-bottom:24px;font-size:.95rem}.placeholder-status{color:var(--white);margin-top:18px;font-size:1rem;font-weight:500}.placeholder-hint{color:#dde4f2a6;margin-top:16px;font-size:.8rem}.start-button{appearance:none;cursor:pointer;background:var(--accent);color:var(--white);border:0;border-radius:10px;padding:14px 40px;font-size:1rem;font-weight:600;transition:background-color .15s,transform .1s}.start-button:hover{background:var(--accent-hover)}.start-button:active{transform:scale(.98)}.error-message{background:var(--error-bg);color:var(--error);border-radius:8px;max-width:420px;margin-bottom:20px;padding:10px 16px;font-size:.88rem;font-weight:500}.error-detail{opacity:.85;word-break:break-word;margin-top:6px;font-size:.78rem;font-weight:400}.spinner{border:3px solid #ffffff2e;border-top-color:var(--accent);border-radius:50%;width:40px;height:40px;animation:.9s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}.lesson-panel{flex-direction:column;gap:20px;display:flex;position:sticky;top:24px}.panel-card{background:var(--white);border:1px solid var(--gray-200);border-radius:var(--radius-md);box-shadow:var(--shadow-card);padding:24px}.panel-heading{color:var(--navy-900);margin-bottom:6px;font-size:1.1rem;font-weight:700}.panel-subheading{color:var(--gray-500);margin-bottom:18px;font-size:.88rem}.panel-section-title{letter-spacing:.08em;text-transform:uppercase;color:var(--gray-500);margin-bottom:12px;font-size:.78rem;font-weight:700}.checklist{flex-direction:column;gap:12px;list-style:none;display:flex}.checklist-item{color:var(--gray-700);align-items:flex-start;gap:12px;font-size:.92rem;display:flex}.checklist-number{background:var(--navy-900);width:24px;height:24px;color:var(--white);border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;margin-top:2px;font-size:.75rem;font-weight:700;display:inline-flex}.question-list{flex-direction:column;gap:10px;list-style:none;display:flex}.question-item{background:var(--gray-100);border:1px solid var(--gray-200);color:var(--navy-800);border-radius:8px;padding:10px 14px;font-size:.88rem;font-style:italic}.footer{background:var(--navy-950);color:var(--navy-100);text-align:center;padding:22px 24px;font-size:.85rem}@media (max-width:900px){.overview-grid{grid-template-columns:repeat(2,1fr)}.classroom{grid-template-columns:1fr}.lesson-panel{position:static}.video-card{min-height:360px}}@media (max-width:560px){.hero{padding:48px 20px 104px}.overview-grid{grid-template-columns:1fr;gap:18px}.overview-card{width:calc(100% - 32px);padding:22px}.classroom{margin-top:24px;padding:0 16px}.video-card{aspect-ratio:auto;min-height:420px}.video-card.is-active{min-height:min(72vh,640px)}.topbar-inner{padding:14px 16px}.brand-name{font-size:.9rem}}