@supports (-webkit-mask:linear-gradient(black,black)){::view-transition-new(root),::view-transition-old(root){animation:none;mix-blend-mode:normal}::view-transition-old(root){z-index:1}::view-transition-new(root){z-index:2;animation:nn-theme-reveal 680ms cubic-bezier(.85,0,.15,1) both}@keyframes nn-theme-reveal{from{clip-path:circle(0% at var(--nn-tx-x,50%) var(--nn-tx-y,50%))}to{clip-path:circle(150vmax at var(--nn-tx-x,50%) var(--nn-tx-y,50%))}}}@media (prefers-reduced-motion:reduce){::view-transition-new(root),::view-transition-old(root){animation:none!important}}.lesson-video-container{width:100%;max-width:100%;margin:2rem 0;background:var(--bg-color,#000);position:relative;border-radius:var(--radius-lg);corner-shape:squircle;overflow:hidden;padding-top:56.25%}.lesson-video-container:has(.video-error-state[style*="display: block"]){padding-top:0;overflow:visible;background:0 0;min-height:220px}.lesson-video-container:has(.video-error-state[style*="display: block"]) .video-error-state{position:static}.video-loading-state{position:absolute;top:0;left:0;right:0;bottom:0;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center}.video-loading-state .loading-spinner{width:24px;height:24px;border:2px solid var(--input-border-color);border-top:2px solid var(--text-primary-color,#fff);border-radius:50%;animation:spin 1s linear infinite;flex-shrink:0;margin:0 auto}@keyframes spin{0%{transform:rotate(0)}100%{transform:rotate(360deg)}}.video-loading-state p{margin:.5rem 0;color:var(--text-tertiary-color);font-size:var(--text-base)!important;font-weight:400;letter-spacing:var(--ls-sm)}.video-error-state{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:.5rem;padding:2.5rem 1.5rem;background:var(--card-bg-color)}.video-error-state[style*="display: block"]{display:flex!important}.video-error-icon{display:grid;place-items:center;width:44px;height:44px;margin-bottom:.75rem;border-radius:50%;color:var(--text-tertiary-color);background:color-mix(in srgb,var(--text-tertiary-color) 10%,transparent)}.video-error-icon i,.video-error-icon svg{width:22px;height:22px}.video-error-title{margin:0;font-size:var(--text-lg);font-weight:600;color:var(--text-primary-color);letter-spacing:var(--ls-md)}.video-error-body{margin:0;max-width:38ch;font-size:var(--text-base);line-height:1.55;color:var(--text-secondary-color)}.video-error-actions{margin-top:1rem}.video-error-state.is-rate-limited{border-radius:var(--radius-md);corner-shape:squircle}.video-error-state.is-rate-limited .video-error-icon{color:var(--brand-color);background:color-mix(in srgb,var(--brand-color) 12%,transparent)}.video-player-container{position:absolute;top:0;left:0;width:100%;height:100%;background:var(--bg-color,#000)}.video-player-container iframe{width:100%;height:100%;border:none;border-radius:var(--radius-lg);corner-shape:squircle;display:block}.video-controls-bar{display:flex;justify-content:center;align-items:center;gap:1rem;border:1px solid var(--input-border-color);border-radius:var(--radius-lg);corner-shape:squircle;padding:.2em;width:fit-content;align-self:center;margin:0 auto}.video-controls-bar .bttn{border-radius:100%}.video-controls-bar svg{width:1.35rem;height:1.35rem}.theater-mode-popup{aspect-ratio:16/9;width:auto!important;height:auto!important;max-width:95vw!important;max-height:82vh!important;padding:0!important;background:var(--bg-color)!important;border-radius:var(--radius-lg)!important;corner-shape:squircle;overflow:hidden}.theater-mode-popup .video-player-container{height:100%}.theater-mode-popup .video-player-container iframe{height:100%;border-radius:var(--radius-lg);corner-shape:squircle}.theater-close-btn{position:absolute!important;top:1rem!important;right:1rem!important;z-index:10!important;border:.5px solid rgba(255,255,255,.25)!important;background:rgba(0,0,0,.25)!important;backdrop-filter:blur(8px)}.theater-close-btn:hover{border-color:rgba(255,255,255,.4)!important}.theater-mode-placeholder{width:100%;height:100%;display:flex;align-items:center;justify-content:center;background:var(--bg-color);color:var(--text-primary-color);border-radius:var(--radius-lg);corner-shape:squircle;padding:2rem;text-align:center}.video-component-container{width:100%}.component-header{margin-bottom:.5rem}.component-title{font-size:var(--text-base);font-weight:500;color:var(--text-primary-color);margin-top:2rem;margin-bottom:.5rem;letter-spacing:var(--ls-md)}.component-instructions{text-align:left;font-size:var(--text-sm);color:var(--text-tertiary-color);padding:0}.timeline-wrapper{display:flex;align-items:center;gap:1rem;padding:2rem .5rem}.timeline-start-icon{flex-shrink:0;color:var(--text-tertiary-color);display:flex;align-items:center}.bookmark-timeline{flex:1;height:50px;display:flex;align-items:center;position:relative}.bookmark-timeline-track{width:100%;height:5px;background:var(--contrast-light-color);border-radius:3px;position:relative;transition:background .3s ease}.timeline-end-timestamp{flex-shrink:0;font-size:var(--text-xs);color:var(--text-tertiary-color);font-weight:500}.stats-content-wrapper{border:dashed var(--input-border-color);border-width:0 0 0 1px;padding:1rem;margin:2rem 0}.stats-content .stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(100px,125px));gap:1rem;padding:0 .75rem}.stats-content .stat-item{display:flex;flex-direction:column;gap:.75rem}.stats-content .stat-label{overflow-wrap:break-word;white-space:normal;color:var(--text-tertiary-color);font-size:var(--text-xs);letter-spacing:var(--ls-sm)}.stats-content .stat-value{color:var(--text-primary-color);font-size:var(--text-2xl);font-weight:600;letter-spacing:var(--ls-md)}.timeline-toggle-btn.active{background:var(--brand-light);color:var(--brand-color);border-color:var(--brand-color)}.stats-toggle-btn.active{background:var(--brand-light);color:var(--brand-color);border-color:var(--brand-color)}.bookmark-dot{position:absolute!important;width:12px;height:12px;background:0 0;border:none;border-radius:50%;top:-4px;transform:translateX(-50%);cursor:pointer;transition:none}.bookmark-dot::before{content:'';position:absolute;top:0;left:0;width:100%;height:100%;background:var(--brand-color);border:1px solid #fff;border-radius:50%;transition:all .2s ease;box-shadow:0 0 20px 2px rgba(0,85,255,.35)}.bookmark-dot:hover::before{transform:scale(1.4);box-shadow:0 0 0 8px rgba(0,114,255,.15),0 2px 4px rgba(0,0,0,.2)}.replay-segment-dot::before{background:#e74c3c;box-shadow:0 0 20px 2px 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ease;color:var(--text-secondary-color)}.bookmark-context-menu .context-menu-item:hover{background:var(--hover-100);color:var(--text-primary-color)}.bookmark-context-menu .context-menu-item i{width:14px;height:14px}@media (max-width:768px){.component-instructions{font-size:calc(var(--text-xs) * .9)}.timeline-wrapper{padding:0 .25rem}}.course-welcome{padding:30px 40px;max-width:900px;margin:20px auto;background-color:var(--color-background-secondary);border-radius:var(--radius-lg);corner-shape:squircle;box-shadow:var(--shadow-medium);color:var(--color-text-primary)}.course-welcome .welcome-header{display:flex;flex-direction:column;align-items:center;text-align:center;margin-bottom:30px;padding-bottom:20px;border-bottom:1px solid var(--color-border-subtle)}.course-welcome .welcome-header h1{font-size:var(--font-size-xxxl);font-weight:var(--font-weight-bold);color:var(--color-text-headings);margin-bottom:15px;line-height:1.2}.course-welcome .course-stats{display:flex;gap:30px;justify-content:center;flex-wrap:wrap}.course-welcome .stat{display:flex;flex-direction:column;align-items:center;min-width:80px}.course-welcome .stat-number{font-size:var(--font-size-xl);font-weight:var(--font-weight-semibold);color:var(--color-primary)}.course-welcome .stat-label{font-size:var(--font-size-sm);color:var(--color-text-secondary);text-transform:uppercase;letter-spacing:.5px}.course-welcome .welcome-content{margin-bottom:30px;font-size:var(--font-size-md);line-height:1.7}.course-welcome .welcome-content p{margin-bottom:1em}.course-welcome .welcome-content h2,.course-welcome .welcome-content h3{margin-top:1.5em;margin-bottom:.5em;color:var(--color-text-headings)}.course-welcome .welcome-actions{display:flex;gap:15px;justify-content:center;align-items:center;flex-wrap:wrap}.course-welcome .welcome-actions .btn{min-width:200px;padding:12px 24px;font-size:var(--font-size-md)}.lesson-content p{line-height:1.8rem;margin:1rem 0}.lesson-content h1{margin-top:1rem;margin-bottom:2rem}.lesson-content h2{margin-bottom:1rem;margin-top:3rem}.lesson-content h3{margin-bottom:.5rem;margin-top:2rem;color:var(--text-secondary)}.lesson-content strong{font-weight:600}.lesson-content a{color:var(--primary-color);background-image:linear-gradient(currentColor,currentColor);background-position:0 100%;background-repeat:no-repeat;background-size:0 1px;line-height:normal;padding-bottom:4px;text-decoration:none;transition:all .25s ease}.lesson-content a:hover{background-size:100% 1px}.lesson-content span[style*="text-decoration: underline"]{text-decoration:none!important;position:relative;display:inline;background:0 0;z-index:10;isolation:isolate;font-weight:500;margin:0 .35rem}.lesson-content span[style*="text-decoration: underline"]::after{content:'';position:absolute;left:-.15rem;right:-.15rem;bottom:-.15rem;height:1.4rem;background:radial-gradient(ellipse 69% 100% at left,rgba(var(--highlight-color),.5) 0,rgba(var(--highlight-color),.4) 50%,rgba(var(--highlight-color),.3) 80%,rgba(var(--highlight-color),.2) 100%);z-index:-1;transform:skew(8deg);border-radius:6px}.lesson-content ol,.lesson-content ul{padding-left:3rem;margin-bottom:1.5rem}.lesson-content ol li:not(:last-child),.lesson-content ul li:not(:last-child){padding-bottom:.8rem}.lesson-content ol li,.lesson-content ul li{margin-left:0;line-height:1.8}.lesson-content ol li li,.lesson-content ol ul li,.lesson-content ul li li,.lesson-content ul ol li{padding:.5rem}.lesson-content figure{margin:0}.lesson-content figcaption{color:var(--text-muted-color);font-size:var(--text-base);line-height:1.4em;text-align:center}.wp-block-details{margin-bottom:1.5em;margin-left:.5em;border:1px solid var(--border-color);border-radius:var(--radius-md);corner-shape:squircle;padding:.75em}.wp-block-details summary{color:var(--primary-color);margin-bottom:.5em;text-decoration:underline;cursor:pointer;font-weight:500}.wp-block-details>:last-child{margin-left:1em}.wp-block-image img{border-radius:var(--radius-sm);corner-shape:squircle;display:block;margin:30px auto;max-width:100%;height:auto;cursor:zoom-in}#lesson-content .wp-block-embed{height:auto;margin:40px auto;width:100%}.wp-block-embed__wrapper{position:relative;padding-bottom:56.25%;height:0;overflow:hidden;border-radius:var(--radius-xs);corner-shape:squircle;box-shadow:0 0 5px 1px rgba(0,0,0,.1);margin:0 1rem}.wp-block-embed__wrapper iframe{position:absolute;top:0;left:0;width:100%;height:100%;border:0;border-radius:var(--radius-xs);corner-shape:squircle}.katex{font-size:1.18em!important;font-weight:500!important}.concept,.formula,.notice,.problem{border-radius:16px!important;margin-top:2em!important;margin-bottom:2em!important;padding:1.5rem;margin:0 1rem;line-height:1.6;font-weight:400!important}.problem{background-color:var(--article-concept-bg)!important;color:var(--article-concept-text)!important;border:1px solid var(--shadow-border);border-radius:6px 6px 16px 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(corner-shape:squircle){.concept,.formula,.notice,.problem{--sq:38px;--sq-tight:10px;corner-shape:squircle}.problem{border-radius:var(--sq-tight) var(--sq-tight) var(--sq) var(--sq)!important}.concept,.formula{border-radius:var(--sq-tight) var(--sq) var(--sq) var(--sq)!important}.notice{border-radius:var(--sq) var(--sq) var(--sq) var(--sq-tight)!important}}.concept li,.concept ul,.formula li,.formula ul,.problem li,.problem ul{list-style-position:inside;margin-bottom:10px!important}.concept li:last-child,.concept ul:last-child,.formula li:last-child,.formula ul:last-child,.problem li:last-child,.problem ul:last-child{margin-bottom:0!important}@media (max-width:768px){.concept,.formula,.notice,.problem{padding:1rem;margin:1.5em 0}}