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560px){.sales-row{grid-template-columns:1fr 78px 92px}.sales-row>:first-child{display:none}.sales-head>:first-child{display:none}}.control-btn.nav-active{background:var(--accent-soft);color:var(--accent-ink);border-color:color-mix(in srgb,var(--accent) 25%,transparent)}.explore-all-row{display:flex;justify-content:center;margin-top:22px}.explore-all-btn{font-weight:700}.lesson-actions{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-bottom:12px}.lesson-actions .control-btn{font-size:13px;padding:0 12px;min-height:38px}.compose-stage{align-items:center;overflow-y:auto;padding:28px 18px}.compose{width:100%;max-width:660px;margin:auto;text-align:center;display:flex;flex-direction:column;align-items:center}.compose-mark{display:grid;place-items:center;width:58px;height:58px;color:#fff;background:linear-gradient(150deg,var(--accent),var(--accent-ink));border-radius:18px;box-shadow:var(--shadow),inset 0 1px 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.footer{position:fixed;left:0;right:0;bottom:0;z-index:61;padding:10px max(14px,env(safe-area-inset-left)) calc(10px + env(safe-area-inset-bottom));background:color-mix(in srgb,var(--surface) 86%,transparent);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border-top:1px solid var(--border);transition:transform .3s ease,opacity .3s ease}.app[data-immersive=true] .footer .lesson-actions,.app[data-immersive=true] .footer .lesson-meta,.app[data-immersive=true] .footer .legal-links{display:none}.app[data-immersive=true][data-controls=hidden] .footer{transform:translateY(115%);opacity:0;pointer-events:none}.immersive-exit{position:absolute;top:max(12px,env(safe-area-inset-top));right:14px;z-index:62;display:grid;place-items:center;width:40px;height:40px;border-radius:999px;border:1px solid var(--border);background:color-mix(in srgb,var(--surface) 86%,transparent);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);color:var(--ink);cursor:pointer;transition:opacity .3s ease}.app[data-controls=hidden] .immersive-exit{opacity:0;pointer-events:none}.audio-spinner{width:11px;height:11px;border:2px solid currentColor;border-top-color:transparent;border-radius:50%;animation:audio-spin .7s linear infinite}@keyframes audio-spin{to{transform:rotate(360deg)}}@media (prefers-reduced-motion: reduce){.audio-spinner{animation-duration:2s}}.topbar{padding-top:max(10px,env(safe-area-inset-top))}.desktop-nav{display:flex;align-items:center;gap:9px}.drawer-scrim{position:fixed;top:0;right:0;bottom:0;left:0;z-index:45;background:#14121c6b;opacity:0;pointer-events:none;transition:opacity .25s ease}.drawer-scrim.open{opacity:1;pointer-events:auto}.history-drawer{position:fixed;top:0;left:0;bottom:0;z-index:46;width:min(344px,86vw);display:flex;flex-direction:column;background:var(--surface);border-right:1px solid var(--border);box-shadow:var(--shadow-lg);transform:translate(-100%);transition:transform .28s cubic-bezier(.4,0,.2,1);padding-top:env(safe-area-inset-top);padding-bottom:env(safe-area-inset-bottom)}.history-drawer.open{transform:translate(0)}.history-head{display:flex;align-items:center;justify-content:space-between;padding:16px 14px 8px 18px}.history-title{font-family:var(--font-display);font-weight:700;font-size:18px;margin:0}.drawer-close{width:40px;height:40px}.history-search{margin:4px 14px 8px;height:42px;font-family:var(--font);font-size:14px;color:var(--ink);background:var(--surface-2);border:1px solid var(--border);border-radius:var(--radius-sm);padding:0 12px}.history-search:focus{outline:none;border-color:var(--accent);box-shadow:var(--ring)}.history-list{flex:1;overflow-y:auto;-webkit-overflow-scrolling:touch;padding:4px 8px 16px;display:flex;flex-direction:column;gap:2px}.history-empty{padding:28px 18px;font-size:14px;line-height:1.5}.history-section{margin:14px 18px 4px;padding-top:12px;border-top:1px solid var(--line, #e3dccb);font-family:var(--font-display);font-size:13px;font-weight:700;text-transform:uppercase;letter-spacing:.04em;opacity:.7}.history-item{display:flex;align-items:center;gap:11px;width:100%;text-align:left;padding:11px 12px;border:none;background:none;border-radius:var(--radius-sm);color:var(--ink);font:inherit;cursor:pointer;min-height:var(--tap);transition:background .15s ease}.history-item:hover{background:var(--accent-soft)}.history-item-mark{display:grid;place-items:center;width:30px;height:30px;flex:0 0 auto;color:var(--accent-ink);background:var(--accent-soft);border-radius:9px}.history-item-body{display:flex;flex-direction:column;min-width:0;flex:1 1 auto}.history-item-title{font-weight:700;font-size:14.5px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.history-item-meta{font-size:12px}.history-badge{flex:0 0 auto;font-size:10.5px;font-weight:700;text-transform:uppercase;letter-spacing:.03em;padding:3px 7px;border-radius:999px;color:var(--ink);background:var(--line, #e3dccb);opacity:.85}.history-badge-created{color:#1f6b3a;background:#2ea05a29}.history-badge-purchased{color:#8a5a00;background:#d69e2e2e}.history-badge-seen{color:var(--muted, #6b6b6b);background:var(--accent-soft)}.history-more{display:block;width:calc(100% - 24px);margin:8px 12px 4px;padding:10px;border:1px dashed var(--line, #e3dccb);background:none;border-radius:var(--radius-sm);color:var(--accent-ink);font:inherit;font-weight:700;font-size:13.5px;cursor:pointer;transition:background .15s ease}.history-more:hover{background:var(--accent-soft)}.tabbar{display:none}@media (max-width: 768px){.desktop-nav{display:none}.tabbar{display:flex;position:fixed;left:0;right:0;bottom:0;z-index:40;background:var(--surface);border-top:1px solid var(--border);box-shadow:0 -3px 12px #2c283814;padding-bottom:env(safe-area-inset-bottom)}.tab{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;min-height:56px;padding:7px 0 6px;background:none;border:none;color:var(--muted);font-family:var(--font);font-size:11px;font-weight:700;cursor:pointer}.tab svg{width:24px;height:24px}.tab.active{color:var(--accent-ink)}.tab:active{background:var(--accent-soft)}.view-scroll{padding-bottom:calc(66px + env(safe-area-inset-bottom))}.compose-stage{padding-bottom:calc(70px + env(safe-area-inset-bottom))}.footer{padding-bottom:calc(60px + env(safe-area-inset-bottom))}}.ob-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:60;display:grid;place-items:center;padding:24px;padding-top:max(24px,env(safe-area-inset-top));padding-bottom:max(24px,env(safe-area-inset-bottom));background:var(--paper);background-image:radial-gradient(var(--paper-2) 1.4px,transparent 1.4px);background-size:22px 22px}.ob-card{width:100%;max-width:420px;display:flex;flex-direction:column;align-items:center;text-align:center}.ob-mark{display:grid;place-items:center;width:64px;height:64px;color:#fff;background:linear-gradient(150deg,var(--accent),var(--accent-ink));border-radius:20px;box-shadow:var(--shadow),inset 0 1px #ffffff4d;transform:rotate(-4deg);margin-bottom:18px}.ob-title{font-family:var(--font-display);font-weight:800;font-size:clamp(24px,6vw,30px);margin:0 0 8px}.ob-sub{font-size:15.5px;line-height:1.55;color:var(--muted);max-width:360px;margin:0 0 22px}.ob-cta{width:100%;max-width:300px;font-size:16px}.ob-year{width:100%;height:50px;margin-bottom:16px;font-size:16px;text-align:center;max-width:300px}.ob-input{width:100%;max-width:300px;height:50px;margin-bottom:14px;font-family:var(--font);font-size:16px;text-align:center;color:var(--ink);background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--press)}.ob-input:focus{outline:none;border-color:var(--accent);box-shadow:var(--ring)}.ob-skip{margin-top:14px;background:none;border:none;color:var(--muted);font:inherit;font-size:14px;text-decoration:underline;cursor:pointer}.ob-dots{display:flex;gap:7px;margin-top:22px}.ob-dot{width:8px;height:8px;border-radius:50%;background:var(--border-strong)}.ob-dot.on{background:var(--accent);width:22px;border-radius:var(--pill)}.notif-nudge{position:fixed;left:50%;transform:translate(-50%);bottom:calc(16px + env(safe-area-inset-bottom));z-index:50;width:min(440px,calc(100vw - 24px));background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);box-shadow:var(--shadow-lg);padding:16px}@media (max-width: 768px){.notif-nudge{bottom:calc(72px + env(safe-area-inset-bottom))}}.notif-nudge-body{display:flex;gap:12px;align-items:flex-start}.notif-nudge-emoji{font-size:26px;line-height:1}.notif-nudge-body strong{font-family:var(--font-display);font-size:16px}.notif-nudge-body p{margin:3px 0 0;font-size:13.5px;line-height:1.45}.notif-nudge-actions{display:flex;gap:8px;justify-content:flex-end;margin-top:12px}.sso-buttons{display:flex;flex-direction:column;gap:9px;margin:4px 0 6px}.sso-btn{display:flex;align-items:center;justify-content:center;gap:10px;width:100%;min-height:46px;font-family:var(--font);font-weight:700;font-size:15px;color:var(--ink);background:var(--surface);border:1.5px solid var(--border-strong);border-radius:var(--radius);cursor:pointer;transition:background .15s ease,box-shadow .15s ease}.sso-btn:hover{background:var(--surface-2);box-shadow:var(--shadow-sm)}.sso-divider{display:flex;align-items:center;gap:12px;margin:12px 0 6px;color:var(--muted);font-size:13px}.sso-divider:before,.sso-divider:after{content:"";flex:1;height:1px;background:var(--border)}