:root.font-small{font-size:14.5px}:root.font-normal{font-size:16px}:root.font-large{font-size:17.5px}:root.font-larger{font-size:19.5px}:root{transition:font-size .3s ease}*{transition:font-size .3s ease}:root.font-small .skeleton{min-height:8px}:root.font-xl .skeleton{max-height:32px}@media (max-width:768px){:root.font-large{font-size:17px}:root.font-xl{font-size:19px}}@media (max-width:480px){:root.font-large{font-size:16px}:root.font-xl{font-size:18px}}#course-header{height:var(--header-height);background:var(--bg-color);border-bottom:1px solid var(--input-border-color);padding:0 var(--spacing-md);position:sticky;top:0;z-index:110}.header-content{display:flex;align-items:center;justify-content:space-between;height:100%;max-width:100%}.header-controls{display:flex;align-items:center;gap:var(--spacing-md)}.control-buttons{display:flex;align-items:center;gap:.5rem}.control-buttons .bttn-icon{position:relative}.control-buttons .theme-icon{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);transition:transform .3s ease-in-out!important}.control-buttons #theme-toggle{position:relative;display:flex;align-items:center;justify-content:center}.control-buttons #theme-toggle .theme-icon{position:absolute;width:calc(var(--bttn-icon-size) * 1.4);height:calc(var(--bttn-icon-size) * 1.4)}.control-buttons #theme-toggle .theme-icon.sun{transform:translate(-50%,-50%) scale(0)}.control-buttons #theme-toggle .theme-icon.moon{transform:translate(-50%,-50%) scale(1)}[data-theme=dark] .control-buttons #theme-toggle .theme-icon.moon{transform:translate(-50%,-50%) rotate(360deg) scale(0)}[data-theme=dark] .control-buttons #theme-toggle .theme-icon.sun{transform:translate(-50%,-50%) scale(1) rotate(360deg)}#course-header #course-title{margin:0;font-size:clamp(1.125rem, 2.5vw, 1.5rem);color:var(--text-primary);font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:40vw}#course-title:has(.brand-name){font-size:clamp(1rem, 1.6vw, 1.2rem);display:flex;align-items:center}#course-title .brand-name,#course-title .brand-section{text-decoration:none;cursor:pointer}#course-title .brand-name{font-family:Geist,sans-serif;font-weight:600;color:var(--text-primary)}#course-title .brand-divider{margin:0 .5rem;color:var(--text-tertiary-color);font-weight:300}#course-title .brand-section{font-weight:400;color:var(--text-secondary-color);font-size:clamp(1rem, 1.1vw, 1.2rem)}#course-header .header-title-logo{display:flex;align-items:center;gap:var(--spacing-sm);flex:none}@media (max-width:1024px){#course-title{max-width:35vw}}@media (max-width:768px){.header-content{flex-direction:row;justify-content:space-between;align-items:center;gap:var(--spacing-sm);padding:0}#course-header{height:var(--header-height);padding:0 var(--spacing-sm)}.header-controls{gap:var(--spacing-sm);flex-shrink:0}#course-title{max-width:none;flex:1;min-width:0;font-size:1rem}.control-buttons{gap:.25rem;flex-shrink:0}}@media (max-width:520px){#course-header{padding:0 var(--spacing-xs)}.header-controls{gap:var(--spacing-xs)}#course-title{font-size:.9rem}.control-buttons{gap:.125rem}.control-buttons .bttn-icon{width:2rem!important;height:2rem!important}}:root{--primary-color:var(--brand-color);--secondary-color:var(--text-secondary-color);--background-color:var(--bg-color);--bg-muted-color:#fbfbfb;--sidebar-bg:#f8fafc;--sidebar-bg-rgb:248,250,252;--border-color:var(--input-border-color);--text-primary:var(--text-primary-color);--text-secondary:var(--text-secondary-color);--success-color:var(--active-green);--highlight-color:0,191,255;--shadow-border:rgba(0, 0, 0, 0.1);--bttn-radius:999px;--card-shadow:rgba(14, 63, 126, 0.06) 0px 0px 0px 1px,rgba(42, 51, 70, 0.03) 0px 1px 1px -0.5px,rgba(42, 51, 70, 0.04) 0px 2px 2px -1px,rgba(42, 51, 70, 0.04) 0px 3px 3px -1.5px,rgba(42, 51, 70, 0.03) 0px 5px 5px -2.5px,rgba(42, 51, 70, 0.03) 0px 10px 10px -5px,rgba(42, 51, 70, 0.03) 0px 24px 24px -8px;--card-bg:radial-gradient(130% 120% at 100% 0%, #fcfcfc 0%, #f9f9f9 75%);--sq-mult:1;--radius-xs:calc(16px * var(--sq-mult));--radius-sm:calc(20px * var(--sq-mult));--radius-md:calc(24px * var(--sq-mult));--radius-lg:calc(28px * var(--sq-mult));--dur-fast:120ms;--dur-base:200ms;--dur-slow:320ms;--ease-out:cubic-bezier(0.22, 1, 0.36, 1);--ease-out-soft:cubic-bezier(0.16, 1, 0.3, 1);--ease-in-out:cubic-bezier(0.65, 0, 0.35, 1);--header-height:70px;--sidebar-width:300px;--spacing-xs:0.5rem;--spacing-sm:1rem;--spacing-md:1.5rem;--spacing-lg:2rem;--control-bar-height:60px;--scrollbar-thumb:rgba(20, 30, 50, 0.22);--scrollbar-thumb-hover:rgba(20, 30, 50, 0.42);--skeleton-base:#e4eaeb;--skeleton-highlight:#e9ecef;--skeleton-shimmer:#d3dbdb;--skeleton-overlay:rgba(240, 244, 246, 0.8);--content-bg:var(--bg-color);--control-bar-bg:var(--bg-color);--breadcrumb-bg:var(--sidebar-bg);--breadcrumb-bg-rgb:248,250,252;--breadcrumb-text:#64748b;--breadcrumb-text-active:#334155;--breadcrumb-border:var(--border-color);--article-problem-bg:color-mix(in srgb, #f3e8ff 40%, white);--article-problem-text:#6b21a8;--article-problem-border:color-mix(in srgb, #c4b5fd 40%, transparent);--article-problem-accent:#8b5cf6;--article-formula-bg:color-mix(in srgb, #ecfeff 40%, white);--article-formula-text:#155e75;--article-formula-border:color-mix(in srgb, #67e8f9 60%, transparent);--article-formula-accent:#22d3ee;--article-concept-bg:#FFEBA1;--article-concept-text:#464f5d;--article-notice-bg:color-mix(in srgb, var(--brand-color) 4%, transparent);--article-notice-text:var(--brand-color);--article-notice-border:color-mix(in srgb, var(--brand-color) 30%, transparent);--article-notice-accent:var(--brand-color);--progress-ring-stroke:rgb(80, 80, 80);--progress-ring-bg:rgba(160, 160, 160, 0.5)}[data-theme=dark]{--content-bg:var(--bg-color);--sidebar-bg:rgb(25, 25, 25);--sidebar-bg-rgb:25,25,25;--bg-muted-color:#151515;--control-bar-bg:var(--bg-color);--highlight-color:0,191,255;--shadow-border:rgba(255, 255, 255, 0.1);--scrollbar-thumb:rgba(255, 255, 255, 0.18);--scrollbar-thumb-hover:rgba(255, 255, 255, 0.34);--card-shadow:inset 0 0 0 1px rgba(255, 255, 255, 0.06),rgba(0, 0, 0, 0.4) 0px 1px 1px -0.5px,rgba(0, 0, 0, 0.4) 0px 2px 2px -1px,rgba(0, 0, 0, 0.4) 0px 3px 3px -1.5px,rgba(0, 0, 0, 0.35) 0px 5px 5px -2.5px,rgba(0, 0, 0, 0.35) 0px 10px 10px -5px,rgba(0, 0, 0, 0.3) 0px 24px 24px -8px;--card-bg:radial-gradient(130% 120% at 100% 0%, #1f1f1f 0%, #171717 75%);--nav-hover-bg:rgba(255, 255, 255, 0.1);--nav-active-bg:rgba(0, 114, 255, 0.2);--nav-active-border:rgba(0, 114, 255, 0.4);--breadcrumb-bg:var(--sidebar-bg);--breadcrumb-bg-rgb:25,25,25;--breadcrumb-text:#94a3b8;--breadcrumb-text-active:#e2e8f0;--breadcrumb-border:var(--border-color);--article-problem-bg:rgba(139, 92, 246, 0.03);--article-problem-text:#f2efff;--article-formula-bg:rgba(56, 189, 248, 0.03);--article-formula-text:#67e8f9;--article-formula-border:rgba(56, 189, 248, 0.25);--article-concept-bg:#FFEBA1;--article-concept-text:#374151;--article-notice-bg:color-mix(in srgb, var(--brand-color) 3%, transparent);--article-notice-text:color-mix(in srgb, var(--brand-color) 80%, white);--article-notice-border:color-mix(in srgb, var(--brand-color) 60%, transparent);--article-notice-accent:var(--brand-color);--progress-ring-stroke:#ffffff;--progress-ring-bg:rgba(255, 255, 255, 0.2);--skeleton-base:#2a2a2a;--skeleton-highlight:#404040;--skeleton-shimmer:#4a4a4a;--skeleton-overlay:rgba(255, 255, 255, 0.1)}*{margin:0;padding:0;box-sizing:border-box}body,html{height:100%;font-family:system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Oxygen,Ubuntu,Cantarell,'Open Sans','Helvetica Neue',sans-serif;background-color:var(--background-color);overflow:hidden}#course-view-container{height:100%;display:grid;grid-template-rows:var(--header-height) 1fr var(--control-bar-height,60px);grid-template-areas:"header" "main" "controls";overflow:hidden}#main-layout{display:grid;--col-left:var(--sidebar-width);--col-right:var(--sidebar-width);grid-template-columns:var(--col-left) 1fr var(--col-right);grid-template-areas:"left-sidebar content right-sidebar";height:100%;overflow:hidden;position:relative}#main-layout.left-collapsed{--col-left:0}#main-layout.right-collapsed{--col-right:0}#main-layout.sidebar-animating{transition:grid-template-columns .35s var(--ease-in-out, ease-in-out)}#main-layout.content-only{grid-template-columns:1fr!important;grid-template-areas:"content"!important}#main-layout.content-only #left-sidebar,#main-layout.content-only #right-sidebar{display:none!important;width:0!important;min-width:0!important;padding:0!important;margin:0!important;border:none!important}body.content-only-layout #bottom-control-bar{display:none!important}body.content-only-layout #course-view-container{grid-template-rows:var(--header-height) 1fr;grid-template-areas:"header" "main"}body.content-only-layout #main-layout{height:100%}#left-sidebar.collapsed{padding-left:0;padding-right:0;border:none}#content-area{grid-area:content;overflow-y:auto;padding:0;background-color:var(--content-bg);min-width:0;min-height:0;width:100%;margin:0;display:block;position:relative;z-index:1;scroll-behavior:smooth;overscroll-behavior-y:contain}#main-layout.content-only #content-area{width:100%!important;min-width:0!important;margin:0!important}#main-layout.left-collapsed #content-area{margin-left:0}#main-layout.right-collapsed #content-area{margin-right:0}body.resizing{cursor:col-resize!important;-webkit-user-select:none;user-select:none}.sidebar.collapsed .sidebar-resize-handle{display:none}#lesson-content{display:block;max-width:1325px;padding:1.5rem;min-height:200px;width:100%;box-sizing:border-box;margin:0 auto}@media (max-width:1400px){#lesson-content{max-width:1200px}}@media (max-width:1200px){#lesson-content{max-width:1000px}}@media (max-width:1000px){#lesson-content{max-width:900px}}@media (max-width:900px){#lesson-content{max-width:100%;padding:3% 6%}}@media (max-width:768px){#lesson-content{padding:1.5rem}}.lesson-content{max-width:700px;width:100%;display:block}#main-layout.left-collapsed .lesson-content{margin:0 auto!important}.notes-placeholder{color:var(--text-secondary);font-style:italic;text-align:center;padding:calc(var(--spacing-md) + 20px)}.loading{opacity:.6;pointer-events:none}.fade-in{animation:fadeIn .3s ease-in}[data-theme=dark] .image-lightbox img,[data-theme=dark] .lesson-content-container img,[data-theme=dark] .lesson-practice-container img{filter:invert(1) hue-rotate(180deg)}[data-theme=dark] .nav-lesson:hover{background:var(--nav-hover-bg)}[data-theme=dark] .nav-lesson.current{background-color:var(--nav-active-bg);border:1px solid var(--nav-active-border);color:var(--text-primary)}[data-theme=dark] .module-lessons{border-color:rgba(255,255,255,.15)}[data-theme=dark] .toggle-icon{color:var(--text-secondary)}@media (max-width:1024px){#main-layout{grid-template-columns:minmax(200px,250px) 1fr minmax(200px,250px)}#main-layout.left-collapsed{grid-template-columns:0 1fr minmax(200px,250px)}#main-layout.right-collapsed{grid-template-columns:minmax(200px,250px) 1fr 0}#main-layout.left-collapsed.right-collapsed{grid-template-columns:0 1fr 0}}@media (max-width:1024px){#main-layout{grid-template-columns:1fr;grid-template-areas:"content";height:100%;overflow:hidden!important;position:relative}#main-layout.left-collapsed,#main-layout.left-collapsed.right-collapsed,#main-layout.right-collapsed{grid-template-columns:1fr;grid-template-areas:"content"}#content-area{grid-area:content;width:100%!important;min-width:0!important;padding:0;display:block!important;overflow-y:auto!important;overflow-x:hidden!important;overscroll-behavior-y:contain!important;-webkit-overflow-scrolling:touch}#left-sidebar{position:fixed;top:var(--header-height);left:0;height:calc(100vh - var(--header-height) - var(--control-bar-height));width:var(--sidebar-width);min-width:250px;max-width:85vw;z-index:1100;transform:translateX(-100%);box-shadow:2px 0 10px rgba(0,0,0,.2);overflow-y:auto;overflow-x:hidden}#main-layout.sidebar-animating #left-sidebar{transition:transform .35s var(--ease-in-out, ease-in-out)}#left-sidebar:not(.collapsed){transform:translateX(0)}#main-layout.content-only #left-sidebar{transform:none!important;position:static!important;box-shadow:none!important}}@media (max-width:768px){.control-bar-container{padding:0 var(--spacing-sm)}.lesson-controls{gap:var(--spacing-xs)}}@media (max-width:480px){.control-bar-container{padding:0 var(--spacing-xs)}.lesson-controls{gap:.25rem}#complete-lesson-btn{padding:var(--spacing-xs);font-size:.875rem}#complete-lesson-btn .btn-text{display:none}#complete-lesson-btn::after{content:attr(aria-label);position:absolute;top:-2.5rem;left:50%;transform:translateX(-50%);background:var(--text-primary);color:var(--background-color);padding:.25rem .5rem;border-radius:.25rem;font-size:.75rem;white-space:nowrap;opacity:0;pointer-events:none;transition:opacity .2s ease}#complete-lesson-btn:hover::after{opacity:1}}@media (max-width:1200px){#content-area{min-width:0!important;flex:1}}@media (max-width:480px){#content-area{width:100%!important;min-width:0!important;max-width:100%!important}#lesson-content{padding:var(--spacing-sm);max-width:none}}@media (max-width:1024px){#content-area{display:block!important;visibility:visible!important;opacity:1!important;width:100%!important;min-width:0!important;grid-area:content!important}#main-layout{width:100%!important;min-width:100%!important;grid-template-columns:1fr!important;grid-template-areas:"content"!important}#left-sidebar,#right-sidebar{position:fixed!important;z-index:100!important}#main-layout.content-only{grid-template-columns:1fr!important;grid-template-areas:"content"!important}#main-layout.content-only #content-area{display:block!important;width:100%!important}}@keyframes content-fade-in{0%{opacity:0;transform:translateY(10px);filter:blur(6px)}100%{opacity:1;transform:translateY(0);filter:blur(0)}}@keyframes fadeIn{from{opacity:0}to{opacity:1}}#report-error-btn{display:none}@supports (corner-shape:squircle){:root{--sq-mult:2}:root{--bttn-radius:1.6rem}.bttn:not(.bttn-icon){corner-shape:squircle}.bttn.bttn-icon{border-radius:30px;corner-shape:squircle}}.module-view{max-width:960px;margin:0 auto;padding:var(--spacing-lg) var(--spacing-md);overflow-x:hidden;background-color:var(--content-bg)}.module-view .module-view-header{text-align:center;margin-bottom:var(--spacing-md);position:relative}.module-view .module-status{display:inline-block;margin-bottom:var(--spacing-sm)}.module-view .module-status.completed{color:var(--success-color);background-color:rgba(0,205,0,.05);box-shadow:0 0 8px 1px rgba(0,205,0,.1);border-radius:var(--radius-xs);corner-shape:squircle;padding:.1rem .4rem;font-weight:400}.module-view .module-status.in-progress{color:#ff9800;background-color:rgba(255,152,0,.05);box-shadow:0 0 8px 1px rgba(255,152,0,.1);border-radius:var(--radius-xs);corner-shape:squircle;padding:.1rem .4rem;font-weight:400}.module-view .module-status.not-started{color:var(--text-muted-color);font-weight:500}.module-view .module-view-title{margin-bottom:var(--spacing-md);color:var(--text-primary);line-height:2rem;font-size:var(--text-xxl);letter-spacing:var(--ls-base)}.module-view .module-prefix{color:var(--text-muted-color)}.module-view .module-view-description{margin-bottom:var(--spacing-lg);padding:var(--spacing-md);background:var(--sidebar-bg);border-radius:var(--radius-md);corner-shape:squircle;box-shadow:0 2px 4px rgba(0,0,0,.05)}.module-view .module-view-description h2{font-size:1.5rem;font-weight:600;margin-bottom:var(--spacing-sm);color:var(--text-primary);padding-bottom:var(--spacing-xs)}.module-view .module-description-content{line-height:1.7;color:var(--text-secondary);font-size:1rem}.module-view .module-view-actions{display:flex;justify-content:center;gap:10px;margin-bottom:var(--spacing-md);flex-wrap:wrap}.module-view .module-view-actions .bttn{min-height:47px;min-width:47px;padding:.8rem 1rem;font-size:var(--text-base)}.module-view .module-view-actions .restart-module-btn:hover{color:#ff2626;background-color:rgba(255,38,38,.1);border-color:rgba(255,38,38,.2)}.module-view .module-action-buttons{display:flex;gap:var(--spacing-xs)}.module-view .module-view-lessons{margin-top:5rem}.module-view .lessons-section-title{display:block;font-size:var(--text-lg);font-weight:400;margin-bottom:var(--spacing-md);color:var(--text-tertiary-color);letter-spacing:var(--ls-base);text-align:left}.module-view .lessons-list{display:flex;flex-direction:column;gap:var(--spacing-md)}.module-view .module-view-lesson{position:relative;border-radius:var(--radius-md);corner-shape:squircle;padding:var(--spacing-lg) var(--spacing-md);display:grid;grid-template-columns:auto 1fr auto;grid-template-areas:"number content actions";gap:var(--spacing-sm) var(--spacing-md);align-items:center;box-shadow:var(--card-shadow);overflow:hidden;z-index:0}.module-view .module-view-lesson{--lesson-grow:1.35}.module-view .module-view-lesson.completed{--lesson-tint:0,175,0}.module-view .module-view-lesson.started{--lesson-tint:251,191,36}.module-view .module-view-lesson.not-started{--lesson-tint:0,114,255}.module-view .module-view-lesson::before{content:'';position:absolute;inset:0;z-index:-1;background:linear-gradient(120deg,rgba(var(--lesson-tint,0,114,255),.22) 0,transparent 65%);transform-origin:left center;transform:scaleX(1);pointer-events:none}.module-view .module-view-lesson:hover::before{transform:scaleX(var(--lesson-grow))}[data-theme=dark] .module-view .module-view-lesson::before{background:linear-gradient(120deg,rgba(var(--lesson-tint,0,114,255),.16) 0,transparent 65%)}.module-view .lesson-number{grid-area:number;width:42px;height:42px;border-radius:var(--radius-lg);corner-shape:squircle;display:flex;align-items:center;justify-content:center;font-weight:600;font-size:var(--text-lg);color:var(--text-primary-color);flex-shrink:0;align-self:center;background:rgba(255,255,255,.15);backdrop-filter:blur(5px);-webkit-backdrop-filter:blur(5px);border:1px solid var(--shadow-border)}[data-theme=dark] .module-view .lesson-number{background:rgba(255,255,255,.05)}.module-view .lesson-content{grid-area:content;min-width:0;display:flex;flex-direction:column;justify-content:center;gap:.5rem}.module-view .lesson-title{font-size:var(--text-lg);font-weight:500;color:var(--text-primary);line-height:1.6;display:flex;align-items:center;gap:.5rem}.module-view .lesson-title svg{flex-shrink:0;width:var(--text-lg)!important;height:var(--text-lg)!important;scale:1.1}.module-view .lesson-status-label{font-size:var(--text-xs);font-weight:500;letter-spacing:var(--ls-lg);text-transform:uppercase}.module-view .module-view-lesson.completed .lesson-status-label{color:var(--success-color)}.module-view .module-view-lesson.started .lesson-status-label{color:#fb9800}.module-view .lesson-description{line-height:1.6;color:var(--text-tertiary-color);font-size:var(--text-base);margin-bottom:0;transition:color var(--dur-base) var(--ease-out)}.module-view .module-view-lesson:hover .lesson-description{color:var(--text-secondary-color)}.module-view .lesson-actions{grid-area:actions;flex-shrink:0;justify-self:end;align-self:center;display:flex;gap:var(--spacing-xs)}.module-view .lesson-actions .start-lesson-btn{padding-left:1.5rem;padding-right:1.5rem;font-size:var(--text-base)}@media (max-width:768px){.module-view .module-view{padding:var(--spacing-md) var(--spacing-sm)}.module-view .module-view-title{font-size:1.875rem}.module-view .module-view-lesson{grid-template-columns:1fr auto;grid-template-areas:"number number" "content actions"}.module-view .lesson-number{justify-self:start;margin-bottom:var(--spacing-xs)}.module-view .lesson-actions{justify-self:end;align-self:start}}@media (max-width:480px){.module-view .module-view-title{font-size:1.6rem}.module-view .module-view-description{padding:var(--spacing-sm)}.module-view .module-view-description h2{font-size:1.3rem}.module-view .module-description-content{font-size:.95rem}.module-view .module-view-lesson{grid-template-columns:1fr;grid-template-areas:"number" "content" "actions";text-align:left}.module-view .lesson-number{justify-self:center;margin-bottom:var(--spacing-xs)}.module-view .lesson-content{align-items:center;text-align:center}.module-view .lesson-title{justify-content:center}.module-view .lesson-actions{margin-top:var(--spacing-sm);justify-content:center}.module-view .lesson-actions{margin-top:var(--spacing-sm);justify-content:center;align-items:center;width:100%}.module-view .lesson-actions .start-lesson-btn{width:100%}}.module-view-footer{margin-top:var(--spacing-2xl);padding-top:var(--spacing-xl);text-align:center;color:var(--text-secondary)}.module-view-lesson-skeleton{display:flex;align-items:flex-start;gap:var(--spacing-lg);padding:var(--spacing-lg);background:var(--bg-secondary);border-radius:var(--radius-md);corner-shape:squircle;margin-bottom:var(--spacing-md);box-shadow:0 0 0 1px var(--shadow-border)}.module-view-lesson-skeleton .lesson-number{display:flex;align-items:center;justify-content:center;width:42px;height:42px;background:var(--bg-primary);border-radius:var(--radius-lg);corner-shape:squircle;font-weight:600;font-size:var(--font-size-lg);color:var(--text-primary);flex-shrink:0}.module-view-lesson-skeleton .lesson-content{flex:1;display:flex;flex-direction:column}.module-view-lesson-skeleton .skeleton-title{height:24px;width:70%;border-radius:var(--radius-xs)}.module-view-lesson-skeleton .skeleton-description{height:16px;width:100%;border-radius:var(--radius-xs)}.module-view-lesson-skeleton .skeleton-status{height:20px;width:120px;border-radius:var(--radius-xs);margin-top:var(--spacing-xs)}.module-view-lesson-skeleton .lesson-actions{flex-shrink:0}.module-view-lesson-skeleton .skeleton-button{height:40px;width:100px;border-radius:var(--radius-sm)}.skeleton{background:linear-gradient(90deg,var(--skeleton-base,#e0e0e0) 0,var(--skeleton-shine,#f0f0f0) 50%,var(--skeleton-base,#e0e0e0) 100%);background-size:200% 100%;animation:skeleton-shine 1.5s ease-in-out infinite}@keyframes skeleton-shine{0%{background-position:-200% 0}100%{background-position:200% 0}}[data-theme=dark] .skeleton{--skeleton-base:#2a2a2a;--skeleton-shine:#333333}#left-sidebar .nav-module{margin-bottom:1rem}#left-sidebar .nav-module .module-header{display:flex;align-items:center;cursor:pointer}#left-sidebar .nav-module .module-info{flex-grow:1;min-width:0;height:2.5rem}#left-sidebar .nav-module .module-title{font-weight:400;font-size:calc(var(--text-base) * .95);line-height:1.4;margin:0;overflow:hidden;white-space:nowrap;letter-spacing:var(--ls-lg);height:2.5rem;align-content:center;font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Oxygen,Ubuntu,Cantarell,'Open Sans','Helvetica Neue',sans-serif;font-optical-sizing:auto;transition:color var(--dur-base, .2s) var(--ease-out, ease),font-weight var(--dur-base, .2s) var(--ease-out, ease);color:var(--text-secondary)}#left-sidebar .nav-module .module-header:hover .module-title{color:var(--text-primary);font-weight:500}#left-sidebar .nav-module .module-toggle{background:0 0;border:none;padding:0;cursor:pointer;line-height:1;display:flex;align-items:center;flex-shrink:0}#left-sidebar .nav-module .toggle-icon{width:1rem;height:1rem;transition:transform .2s ease;align-self:center}#left-sidebar .nav-module.expanded .toggle-icon{transform:rotate(90deg)}#left-sidebar svg{stroke:currentColor!important;stroke-width:1.8}#left-sidebar .nav-module .module-lessons{display:none!important;padding:0;overflow:hidden;background:var(--lesson-bg);margin-top:var(--spacing-xs)}#left-sidebar .nav-module.expanded .module-lessons{display:block!important}#left-sidebar .module-lessons.expanded{display:block!important}#left-sidebar .nav-lesson{padding:0 .75rem;cursor:pointer;height:2.5rem;display:flex;border-radius:var(--radius-lg);corner-shape:squircle;margin-bottom:var(--spacing-xs);background:0 0;border:1px solid transparent;transition:border-color var(--dur-fast, .15s) var(--ease-out, ease),color var(--dur-fast, .15s) var(--ease-out, ease);position:relative;margin-left:2px;margin-right:2px}#left-sidebar .nav-lesson:hover{border-color:var(--border-color);opacity:1!important}#left-sidebar .nav-lesson.current{border-color:rgba(0,114,255,.5);box-shadow:0 0 1px 0 #0072ff;color:var(--text-primary)}#left-sidebar .nav-lesson.current::before{content:'';position:absolute;right:.5rem;top:50%;transform:translateY(-50%);width:.25rem;height:.25rem;background:var(--active-green);border-radius:50%;animation:pulse-dot 3.5s ease-in-out infinite;z-index:3}@keyframes pulse-dot{0%,100%{opacity:.3;transform:translateY(-50%) scale(1)}50%{opacity:1;transform:translateY(-50%) scale(1.15)}}#left-sidebar .nav-lesson.completed{opacity:.75}#left-sidebar .lesson-title-row{display:flex;align-items:center;width:100%;min-width:0;margin:0}#left-sidebar .lesson-title{font-size:var(--text-md);line-height:normal;color:var(--text-secondary);overflow:hidden;text-overflow:ellipsis;white-space:nowrap;display:flex;align-items:center;flex:1;height:2.25rem;font-optical-sizing:auto}#left-sidebar .lesson-title .marquee-text{padding:.69rem 0;margin:-.69rem 0}#left-sidebar .lesson-title svg,#left-sidebar .module-title svg{width:1.05rem;height:1.05rem;flex-shrink:0;vertical-align:middle;margin-right:7px}#left-sidebar .lesson-progress-indicator{flex-shrink:0;width:1.2rem;height:1.2rem;display:flex;align-items:center;justify-content:center}#left-sidebar .circular-progress-sidebar{position:relative;width:1.2rem;height:1.2rem;display:flex;align-items:center;justify-content:center}#left-sidebar .progress-circle{width:1.2rem;height:1.2rem;transform:rotate(-90deg);position:absolute;top:0;left:0}#left-sidebar .progress-circle-bg{fill:none;stroke:var(--border-color);stroke-width:2;opacity:.6}#left-sidebar .progress-circle-fill{fill:none;stroke:var(--primary-color);stroke-width:2;stroke-linecap:round;transition:stroke-dashoffset .3s ease}#left-sidebar .circular-progress-sidebar[data-progress="0"] .progress-circle-fill{opacity:0}#left-sidebar .title-check-icon,#left-sidebar .title-check-icon svg,#left-sidebar svg.title-check-icon{width:1.2rem;height:1.2rem;color:var(--success-color);stroke-width:2.5;flex-shrink:0}.lessons-loading{padding:var(--spacing-md);text-align:center;color:var(--text-secondary);font-size:var(--font-size-sm)}.lessons-loading.active{display:flex;align-items:center;justify-content:center;gap:var(--spacing-sm)}.lessons-loading .loading-icon{width:16px;height:16px;animation:spin 1s linear infinite}@keyframes spin{0%{transform:rotate(0)}100%{transform:rotate(360deg)}}.lessons-error{padding:var(--spacing-md);text-align:center;color:var(--color-danger);font-size:var(--font-size-sm)}.lessons-error p{margin:0 0 var(--spacing-sm) 0}.lessons-error .retry-btn{padding:var(--spacing-xs) var(--spacing-sm);background:var(--color-danger);color:#fff;border:none;border-radius:var(--radius-sm);corner-shape:squircle;font-size:var(--font-size-xs);cursor:pointer;transition:opacity .2s ease}.lessons-error .retry-btn:hover{opacity:.8}.no-lessons{padding:var(--spacing-md);text-align:center;color:var(--text-secondary);font-size:var(--font-size-sm);font-style:italic}.lesson-practice-container{width:100%;max-width:100%;position:relative;overflow:visible;min-height:400px}.practice-question{width:100%}.question-header-nav{display:flex;align-items:center;justify-content:space-between;margin-bottom:1rem;flex-wrap:wrap;gap:1rem}.question-header-nav h3{margin:0}.question-nav-buttons{display:flex;align-items:center;gap:.75rem}.question-nav-buttons .bttn{display:flex;align-items:center;justify-content:center}.question-nav-buttons .bttn:disabled{opacity:.5;cursor:not-allowed}.question-meta-wrapper{display:inline-flex;align-items:center;gap:.5rem;margin-bottom:1.5rem}.question-meta-wrapper .meta-divider::before{content:"•";color:var(--text-tertiary-color);font-weight:700}.question-meta-wrapper .attempts-count{color:var(--text-tertiary-color);font-size:var(--text-sm)}.question-type-badge{display:inline-flex;align-items:center;justify-content:center;padding:var(--badge-padding-y) var(--badge-padding-x);font-size:var(--text-sm);font-weight:600;letter-spacing:var(--ls-base);border-radius:5px;line-height:normal}.question-type-badge.mcq{background:color-mix(in srgb,var(--brand-color) 15%,transparent);color:var(--brand-color);border:1px solid color-mix(in srgb,var(--brand-color) 25%,transparent)}.question-type-badge.frq{background:color-mix(in srgb,var(--active-green) 15%,transparent);color:var(--active-green);border:1px solid color-mix(in srgb,var(--active-green) 25%,transparent)}.question-type-badge.gq{background:color-mix(in srgb,#ff6b35 15%,transparent);color:#ff6b35;border:1px solid color-mix(in srgb,#ff6b35 25%,transparent)}.practice-content-container.is-switching .practice-question>:not(.question-header-nav){opacity:0;filter:blur(6px)}.practice-question>:not(.question-header-nav){transition:opacity var(--dur-fast) var(--ease-out),filter var(--dur-fast) var(--ease-out)}@media (prefers-reduced-motion:reduce){.practice-content-container.is-switching .practice-question>:not(.question-header-nav){opacity:1;filter:none}}.question-navigation{display:flex;align-items:center;justify-content:space-between;margin-bottom:2rem}.nav-btn{display:flex;align-items:center;gap:.5rem;min-width:100px}.nav-btn:disabled{opacity:.5;cursor:not-allowed}.question-progress{font-size:var(--text-sm);font-weight:500;color:var(--text-secondary-color);letter-spacing:var(--ls-sm)}.question-content{margin-bottom:2rem}[data-theme=dark] .question-images{background:#000;padding:1.5rem;border-radius:var(--radius-md);corner-shape:squircle}.question-text{font-size:var(--text-base);color:var(--text-primary-color);margin-bottom:1.5rem}.choice-images,.part-images,.question-images{display:flex;flex-direction:column;gap:1rem;margin:1.5rem 0}.choice-image,.part-image,.question-image{max-width:100%;height:auto;max-height:400px;border-radius:var(--radius-md);corner-shape:squircle;align-self:center;cursor:zoom-in}.mcq-choices{display:flex;flex-direction:column;gap:.75rem;margin-top:1.5rem;margin-bottom:3rem}.mcq-choice{display:flex;align-items:center;gap:.85rem;padding:.6rem 1.1rem;border:1px solid var(--input-border-color);border-radius:var(--radius-md);corner-shape:squircle;cursor:pointer;transition:border-color var(--dur-fast) var(--ease-out),background-color var(--dur-fast) var(--ease-out),box-shadow var(--dur-fast) var(--ease-out);position:relative}.mcq-choice p{margin:0}.choice-text,.mcq-choice p{line-height:1.5}.mcq-choice .katex-display{margin:0}.mcq-choice:hover{border-color:var(--brand-light);background-color:color-mix(in srgb,var(--brand-color) 4%,transparent)}.mcq-choice:has(.mcq-input:checked){border-color:var(--brand-color);background-color:color-mix(in srgb,var(--brand-color) 8%,transparent);box-shadow:0 0 0 1px var(--brand-color)}.choice-letter{flex-shrink:0;font-weight:600;font-variant-numeric:tabular-nums;color:var(--text-secondary);min-width:1.4em}.mcq-choices.is-single .mcq-input{position:absolute;opacity:0;width:1px;height:1px;pointer-events:none}.mcq-choices.is-multi .mcq-input{flex-shrink:0;margin:0;accent-color:var(--brand-color);width:1.1rem;height:1.1rem;cursor:pointer}.choice-text{font-size:var(--text-base)}.frq-parts{margin:1.5rem 0}.frq-parts.frq-accordion{display:block}.frq-accordion{--frq-radius:var(--radius-md);--frq-duration:0.26s;--frq-ease:linear(
        0 0%, 0.2688 9.91%, 0.3859 15%, 0.4917 20.19%, 0.5865 25.5%,
        0.6705 30.93%, 0.7441 36.51%, 0.8075 42.26%, 0.8593 47.98%,
        0.9022 53.93%, 0.9366 60.13%, 0.963 66.67%, 0.9812 73.4%,
        0.9929 80.76%, 0.9986 88.89%, 1 100%
    );--frq-bounce-duration:1s;--frq-bounce:linear(
        0 0%, 0.5571 7.53%, 0.8252 11.98%, 0.9337 14.38%, 1.0166 16.8%,
        1.0765 19.31%, 1.1146 21.97%, 1.1263 23.47%, 1.1325 25.06%,
        1.133 26.76%, 1.128 28.62%, 1.1094 31.9%, 1.0484 39.77%,
        1.0218 43.85%, 1.0011 48.42%, 0.9895 53.23%, 0.9861 59.8%,
        1 81.27% 100%
    );--frq-detach-margin:0.5rem;--frq-reveal-blur:10px;--frq-reveal-opacity:0.4;--frq-reveal-y:1rem}.frq-part{position:relative;background:var(--card-bg-color,transparent);border:1px solid var(--border-color);border-top-color:transparent;corner-shape:squircle;transition-property:border-radius,margin,border-color,translate;transition-duration:var(--frq-duration);transition-timing-function:var(--frq-ease)}.frq-part:first-of-type{border-top-color:var(--border-color);border-top-left-radius:var(--frq-radius);border-top-right-radius:var(--frq-radius)}.frq-part:last-of-type{border-bottom-left-radius:var(--frq-radius);border-bottom-right-radius:var(--frq-radius)}.frq-part:has(+ .frq-part[open]){border-bottom-left-radius:var(--frq-radius);border-bottom-right-radius:var(--frq-radius)}.frq-part[open]+.frq-part{border-top-color:var(--border-color);border-top-left-radius:var(--frq-radius);border-top-right-radius:var(--frq-radius)}.frq-part[open]{margin-block:var(--frq-detach-margin);border-radius:var(--frq-radius);border-top-color:var(--border-color);z-index:2}.frq-part[open]:first-of-type{margin-block-start:0}.frq-part[open]:last-of-type{margin-block-end:0}.frq-part-summary{display:flex;align-items:center;justify-content:space-between;gap:.5rem;padding:1rem 1.5rem;cursor:pointer;user-select:none;list-style:none}.frq-part-summary::-webkit-details-marker{display:none}.frq-part-summary::marker{content:'';font-size:0}.frq-part-icon{width:18px;height:18px;flex-shrink:0;color:var(--text-muted-color);transition:transform var(--frq-duration) var(--frq-ease),color var(--dur-fast) var(--ease-out)}.frq-part[open] .frq-part-icon{transform:rotate(135deg)}.frq-part-summary:hover .frq-part-icon{color:var(--text-primary-color)}.frq-part-content{padding:0 1.5rem 1.25rem;opacity:var(--frq-reveal-opacity);translate:0 var(--frq-reveal-y);filter:blur(var(--frq-reveal-blur));transition-property:opacity,translate,filter;transition-duration:var(--frq-duration);transition-timing-function:var(--frq-ease)}.frq-part[open] .frq-part-content{opacity:1;translate:0 0;filter:blur(0)}.frq-part::details-content{height:0;overflow:hidden;transition-property:content-visibility,height;transition-behavior:allow-discrete;transition-duration:var(--frq-bounce-duration);transition-timing-function:var(--frq-bounce)}.frq-part[open]::details-content{height:var(--frq-content-height,fit-content)}@supports (interpolate-size:allow-keywords){.frq-accordion{interpolate-size:allow-keywords}.frq-part[open]::details-content{height:fit-content}}@media (prefers-reduced-motion:reduce){.frq-part,.frq-part-content,.frq-part-icon,.frq-part::details-content{transition-duration:1ms}.frq-part-content{opacity:1;translate:0;filter:none}}.frq-meta{display:flex;align-items:center;gap:1rem}.frq-label{font-size:var(--text-base);font-weight:600;color:var(--text-primary-color);letter-spacing:var(--ls-md)}.frq-points{font-size:var(--text-sm);color:var(--text-tertiary-color);background:var(--card-bg-color);padding:.25rem .5rem;border-radius:6px;border:1px solid var(--input-border-color);transition:all .2s ease;letter-spacing:var(--ls-lg)}.part-question{font-size:var(--text-base);line-height:1.6;color:var(--text-primary-color);margin-bottom:1rem}.frq-answer,.gq-answer-input{display:flex;width:100%;min-height:120px;max-height:300px;overflow-y:auto;padding:.75rem .9rem;border:1px solid var(--border-color);border-radius:var(--radius-sm);corner-shape:squircle;font-family:inherit;font-size:var(--text-base);line-height:1.7;color:var(--text-primary-color);background:var(--bg-color);resize:vertical;transition:border-color .25s ease,box-shadow .25s ease,background-color .25s ease}.frq-answer{background:color-mix(in srgb,var(--bg-color) 70%,var(--card-bg-color,transparent))}@supports (field-sizing:content){.frq-answer,.gq-answer-input{field-sizing:content;resize:none}}.frq-answer:focus,.gq-answer-input:focus{outline:0;border-color:var(--brand-light);box-shadow:0 0 0 2px color-mix(in srgb,var(--brand-color) 20%,transparent)}.frq-answer::placeholder,.gq-answer-input::placeholder{color:var(--text-tertiary-color)}.gq-answer{margin:1.5rem 0}.practice-question .incorrect{border-color:#ee1c1c!important;background:linear-gradient(169deg,color-mix(in srgb,#ee1c1c 8%,var(--bg-color)) 0,color-mix(in srgb,#ee1c1c 4%,var(--bg-color)) 55%,transparent 100%)!important;box-shadow:0 0 12px 0 color-mix(in srgb,#ee1c1c 20%,transparent)!important}.practice-question .correct{border-color:var(--active-green)!important;background:linear-gradient(169deg,color-mix(in srgb,var(--active-green) 8%,var(--bg-color)) 0,color-mix(in srgb,var(--active-green) 4%,var(--bg-color)) 55%,transparent 100%)!important;box-shadow:0 0 12px 0 color-mix(in srgb,var(--active-green) 20%,transparent)!important}.practice-question .partial{border-color:#f3a31a!important;background:linear-gradient(169deg,color-mix(in srgb,#f3a31a 8%,var(--bg-color)) 0,color-mix(in srgb,#f3a31a 4%,var(--bg-color)) 55%,transparent 100%)!important;box-shadow:0 0 12px 0 color-mix(in srgb,#f3a31a 20%,transparent)!important}.question-actions{display:flex;align-items:center;justify-content:flex-start;flex-wrap:wrap;gap:1rem}.lesson-practice-container .bttn{min-height:2.5rem;min-width:2.5rem}.bttn .animate-spin{animation:spin 1s linear infinite}.question-feedback{margin:1.5rem 0;padding:1.5rem;border-radius:var(--radius-md);corner-shape:squircle;border:1px solid var(--input-border-color);background:var(--bg-color);font-size:var(--text-base)}.feedback-status{display:flex;align-items:center;gap:.75rem;flex-wrap:wrap}.status-text{font-size:var(--text-base);font-weight:500;letter-spacing:var(--ls-md)}.score-text{font-size:var(--text-sm);color:var(--text-secondary-color);margin-left:auto}.feedback-content{padding-top:1rem;border-top:1px solid var(--input-border-color);margin-top:1rem}.question-explanation{margin-top:2rem}.explanation-content{display:flex;flex-direction:column;gap:1.5rem}.answer-text{border:2px dashed var(--shadow-border);border-radius:var(--radius-md);corner-shape:squircle;padding-left:2rem}.answer-text ol,.answer-text ul{list-style-type:lower-alpha;margin:1rem 0}.collapsible-section{box-shadow:0 0 1px 1px var(--shadow-border);border:.5px solid transparent;border-radius:var(--radius-md);corner-shape:squircle;transition:all .3s cubic-bezier(.4, 0, .2, 1)}.collapsible-section.is-expanded{box-shadow:-.5px .5px 0 .5px var(--shadow-border);border:.5px solid var(--border-color)}.collapsible-section--answer.is-expanded,.collapsible-section--explanation.is-expanded{box-shadow:0 0 1px 1px transparent;border:.5px solid transparent;border-radius:var(--radius-md)!important;corner-shape:squircle;overflow:visible!important}.collapsible-header{display:flex;align-items:center;padding:1rem 1.5rem;justify-content:space-between;flex-wrap:wrap;gap:.5rem;cursor:pointer;transition:all .3s cubic-bezier(.4, 0, .2, 1);user-select:none}.collapse-icon{width:20px;height:20px;color:var(--text-muted-color);transition:transform .3s cubic-bezier(.4, 0, .2, 1),color .2s ease}.collapsible-section:not(.is-expanded) .collapse-icon[data-lucide=chevron-up]{transform:rotate(180deg)}.collapsible-header:hover .collapse-icon{color:var(--text-primary-color)}.collapsible-content{overflow:hidden;transition:max-height .4s cubic-bezier(.4, 0, .2, 1),opacity .3s cubic-bezier(.4, 0, .2, 1),padding .3s cubic-bezier(.4, 0, .2, 1)}.collapsible-content.is-expanded{max-height:fit-content;opacity:1;overflow:visible!important;padding:1.25rem}.collapsible-content.is-collapsed{max-height:0;opacity:0;padding:0;border:none!important}.collapsible-section--answer .collapsible-content.is-expanded,.collapsible-section--explanation .collapsible-content.is-expanded{margin:0;overflow:visible!important;max-width:none!important}.lesson-practice-error{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:3rem 2rem;background:var(--card-bg-color);border-radius:var(--radius-md);corner-shape:squircle;border:1px solid var(--input-border-color);margin:2rem 0}.lesson-practice-error .error-icon{width:48px;height:48px;color:var(--text-tertiary-color);margin-bottom:1rem}.lesson-practice-error h3{font-size:var(--text-lg);font-weight:500;color:var(--text-primary-color);margin-bottom:.5rem;letter-spacing:var(--ls-md)}.lesson-practice-error p{font-size:var(--text-base);color:var(--text-secondary-color);margin-bottom:1.5rem;max-width:400px}.question-explanation{scrollbar-width:thin;scrollbar-color:var(--text-tertiary-color) var(--card-bg-color)}.question-explanation::-webkit-scrollbar{height:8px}.question-explanation::-webkit-scrollbar-track{background:var(--card-bg-color);border-radius:4px}.question-explanation::-webkit-scrollbar-thumb{background:var(--text-tertiary-color);border-radius:4px}.question-explanation::-webkit-scrollbar-thumb:hover{background:var(--text-secondary-color)}.practice-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;min-height:400px;z-index:10}.practice-loading-state[style*="display: none"]{display:none!important;visibility:hidden!important;z-index:-1!important}.practice-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)}}.practice-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)}.practice-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);min-height:400px;z-index:10}.practice-error-state[style*="display: none"]{display:none!important;visibility:hidden!important;z-index:-1!important}.practice-error-state[style*="display: block"]{display:flex!important}.practice-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)}.practice-error-icon i,.practice-error-icon svg{width:22px;height:22px}.practice-error-title{margin:0;font-size:var(--text-lg);font-weight:600;color:var(--text-primary-color);letter-spacing:var(--ls-md)}.practice-error-body{margin:0;max-width:38ch;font-size:var(--text-base);line-height:1.55;color:var(--text-secondary-color)}.practice-error-actions{margin-top:1rem}.practice-error-state.is-rate-limited{border-radius:var(--radius-md);corner-shape:squircle}.practice-error-state.is-rate-limited .practice-error-icon{color:var(--brand-color);background:color-mix(in srgb,var(--brand-color) 12%,transparent)}.practice-content-container{position:relative;width:100%;height:100%;min-height:400px;z-index:1}.explanation-content,.question-explanation{overflow:visible!important}.table-breakout-wrapper{position:relative;margin:0 0 1rem 0;max-width:100%;overflow-x:auto;overflow-y:visible}.table-breakout-wrapper.scrollable{padding:15px 10px 30px 10px}.table-breakout-wrapper table{margin:0 auto;width:100%;max-width:100%}@media (min-width:1100px){.table-breakout-wrapper{margin:0 calc(-1 * min(6rem,12vw)) 1.5rem;max-width:min(1200px,90vw);overflow-x:visible}}@media (max-width:1099px){.table-breakout-wrapper table{min-width:950px}}.table-scroll-indicator{position:absolute;top:0;left:1.5rem;font-size:var(--text-sm);color:var(--text-muted-color);background:0 0;padding:0;line-height:1;opacity:0;transition:opacity .3s ease;pointer-events:none;z-index:10}.table-breakout-wrapper.scrollable:hover .table-scroll-indicator{opacity:.9}.feedback-actions{margin-top:1rem;display:flex;gap:.75rem;align-items:center}.retry-question-btn{background:var(--card-bg-color);border:1px solid var(--input-border-color);color:var(--text-primary-color);transition:all .2s ease}.retry-question-btn:hover{background:var(--card-hover-bg-color);border-color:var(--text-secondary-color);transform:translateY(-1px)}.part-feedback-display{margin-top:1rem;padding-left:1rem;border-left:2px solid var(--text-secondary-color);font-size:var(--text-base);line-height:1.8;color:var(--text-secondary-color)}.part-feedback-display p{margin:0 0 .5rem 0}.part-feedback-display p:last-child{margin-bottom:0}.practice-input-wrapper{position:relative;width:100%}.practice-input-wrapper.drag-over{border-radius:5px;outline:2px dashed rgba(168,85,247,.6);outline-offset:.75rem;background:linear-gradient(120deg,rgba(34,211,238,.08) 0,rgba(168,85,247,.06) 25%,rgba(251,146,60,.05) 50%,rgba(250,204,21,.06) 75%,rgba(34,197,94,.08) 100%);position:relative}.practice-input-wrapper.drag-over::before{content:'';position:absolute;inset:0;background:linear-gradient(120deg,rgba(165,243,252,.25) 0,rgba(196,181,253,.2) 33%,rgba(254,215,170,.15) 66%,rgba(187,247,208,.2) 100%);backdrop-filter:blur(2px);border-radius:10px;pointer-events:none;z-index:5}[data-theme=dark] .practice-input-wrapper.drag-over::before{background:linear-gradient(120deg,rgba(6,182,212,.15) 0,rgba(124,58,237,.12) 33%,rgba(251,146,60,.08) 66%,rgba(52,211,153,.12) 100%)}.practice-input-wrapper.drag-over::after{content:'↓ Drop images here';position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);color:var(--text-primary-color);font-weight:500;font-size:var(--text-lg);letter-spacing:var(--ls-sm);pointer-events:none;z-index:100;padding:.5rem 1rem}.practice-input-wrapper .frq-answer,.practice-input-wrapper .gq-answer-input{padding-bottom:3.5rem;position:relative;z-index:0}.practice-toolbar-floating{position:absolute;bottom:.75rem;left:.75rem;right:.75rem;display:flex;align-items:center;justify-content:space-between;pointer-events:none;z-index:5}.toolbar-word-pill{background:rgba(255,255,255,.25);backdrop-filter:blur(5px);padding:.35rem .75rem;font-size:var(--text-xs);border-radius:50px;font-weight:300;color:var(--text-tertiary-color);box-shadow:0 0 0 1px var(--shadow-border);pointer-events:auto;transition:all .2s ease;transform:scale(.9);opacity:0;align-self:end}.practice-input-wrapper:focus-within .toolbar-word-pill{opacity:1;transform:scale(1)}[data-theme=dark] .toolbar-word-pill{background:rgba(30,30,30,.25)}.toolbar-word-pill.approaching-limit{color:#ef8000;background:rgba(255,180,0,.15);backdrop-filter:blur(8px);border:1px solid #ef8000;box-shadow:none;animation:pulse .5s ease}.toolbar-word-pill.over-limit{color:#ff3e3e;background:rgba(255,62,62,.2);backdrop-filter:blur(8px);border:1px solid #ff3e3e;box-shadow:none;animation:pulse .5s ease}@keyframes pulse{0%,100%{transform:scale(1)}50%{transform:scale(1.05)}}.toolbar-image-section{display:flex;align-items:center;gap:.75rem;pointer-events:auto}.toolbar-image-pills{display:none;gap:.7rem;transition:all .3s ease}.toolbar-image-thumb{position:relative;width:50px;height:50px;border-radius:30%;overflow:visible;cursor:pointer;transition:all .2s ease;flex-shrink:0;box-shadow:0 0 0 1px var(--shadow-border)}.toolbar-image-thumb:hover{transform:scale(1.1)}.toolbar-image-thumb img{width:100%;height:100%;object-fit:cover;border-radius:30%;cursor:zoom-in}.toolbar-remove-btn{position:absolute;top:-4px;right:-4px;width:18px;height:18px;background:#dc2626;color:#fff;border:2px solid #fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:12px;line-height:1;cursor:pointer;opacity:0;transform:scale(.8);transition:all .2s ease}.toolbar-image-thumb:hover .toolbar-remove-btn{opacity:1;transform:scale(1)}.toolbar-upload-btn{width:48px;height:48px;border-radius:50%;min-width:48px;background:rgba(255,255,255,.25)!important;backdrop-filter:blur(5px);border:none!important;box-shadow:0 0 0 1px var(--shadow-border)!important;transition:transform var(--dur-fast) var(--ease-out),background var(--dur-fast) var(--ease-out),box-shadow var(--dur-fast) var(--ease-out)!important;position:relative;overflow:visible}[data-theme=dark] .toolbar-upload-btn{background:rgba(30,30,30,.25)!important}.toolbar-upload-btn:hover{transform:scale(1.1);background:rgba(255,255,255,.35)!important;box-shadow:0 0 0 1px var(--brand-light),0 4px 12px rgba(168,85,247,.2)!important}[data-theme=dark] .toolbar-upload-btn:hover{background:rgba(50,50,50,.35)!important}.toolbar-upload-btn:active{transform:scale(.92);transition:transform var(--dur-fast) var(--ease-out)!important}.toolbar-upload-btn::after{content:'';position:absolute;top:50%;left:50%;width:100%;height:100%;border-radius:50%;background:radial-gradient(circle,rgba(168,85,247,.3) 0,transparent 70%);transform:translate(-50%,-50%) scale(0);opacity:0;transition:transform var(--dur-slow) var(--ease-out),opacity var(--dur-slow) var(--ease-out);pointer-events:none}.toolbar-upload-btn:active::after{transform:translate(-50%,-50%) scale(2);opacity:1;transition:all .3s ease-out}.toolbar-upload-btn svg{width:22px;height:22px;position:relative;z-index:1}@media (max-width:640px){.toolbar-word-pill{font-size:var(--text-xxs)}.toolbar-upload-btn{scale:0.95}.practice-input-wrapper .frq-answer,.practice-input-wrapper .gq-answer-input{padding-bottom:5rem}}.toolbar-upload-btn.uploading{pointer-events:none;opacity:.5;cursor:not-allowed}.toolbar-image-thumb.uploading{pointer-events:none}.toolbar-image-thumb.uploading::before{content:'';position:absolute;top:0;left:0;width:100%;height:100%;background:rgba(255,255,255,.9);border-radius:30%;z-index:5}.toolbar-image-thumb.uploading::after{content:'';position:absolute;top:12px;left:12px;width:20px;height:20px;border:3px solid rgba(0,0,0,.1);border-top:3px solid var(--brand-color);border-radius:50%;animation:spin .8s linear infinite;z-index:10}.toolbar-image-thumb.upload-success{animation:successPulse .5s ease}@keyframes successPulse{0%{transform:scale(1);box-shadow:0 0 0 0 rgba(34,197,94,.4)}50%{transform:scale(1.05);box-shadow:0 0 0 8px rgba(34,197,94,0)}100%{transform:scale(1);box-shadow:0 0 0 0 rgba(34,197,94,0)}}@media (max-width:768px){.feedback-actions{flex-direction:column;align-items:stretch}.retry-question-btn{width:100%;justify-content:center}.question-actions{flex-direction:column;gap:1rem}.question-actions .bttn{width:100%;justify-content:center}.question-header-nav{flex-direction:column;align-items:flex-start;gap:.75rem}.question-nav-buttons{align-self:stretch;justify-content:space-between}}.answer-text img,.explanation-text img{max-width:100%;height:auto;border-radius:var(--radius-md);corner-shape:squircle;display:block;margin:1.5rem auto;cursor:pointer;transition:transform .2s ease;cursor:zoom-in}[data-theme=dark] .answer-text img,[data-theme=dark] .explanation-text img{background:#000;padding:1rem}.sidebar-header{margin:var(--spacing-md) 0}.sidebar-header h3{font-size:var(--text-base);font-weight:500;color:var(--text-primary)}#left-sidebar{grid-area:left-sidebar;border-right:1px solid var(--border-color);transition:padding .35s var(--ease-in-out, ease-in-out),border-color .35s var(--ease-in-out, ease-in-out);position:relative;margin:0;padding:1.5rem 1rem;padding-top:0;background:var(--sidebar-bg);overflow-y:auto;overflow-x:hidden;z-index:10;box-sizing:border-box;-webkit-user-select:none;user-select:none;scrollbar-width:thin;scrollbar-color:transparent transparent}#left-sidebar:hover{scrollbar-color:var(--scrollbar-thumb,rgba(120,120,120,0.35)) transparent}#left-sidebar::-webkit-scrollbar{width:6px}#left-sidebar::-webkit-scrollbar-track{background:0 0}#left-sidebar::-webkit-scrollbar-thumb{background:0 0;border-radius:999px;border:1px solid transparent;background-clip:padding-box;transition:background-color var(--dur-base, .2s) var(--ease-out, ease)}#left-sidebar:hover::-webkit-scrollbar-thumb{background:var(--scrollbar-thumb,rgba(120,120,120,.35));background-clip:padding-box}#left-sidebar::-webkit-scrollbar-thumb:hover{background:var(--scrollbar-thumb-hover,rgba(120,120,120,.6));background-clip:padding-box}#left-sidebar #course-navigation,#left-sidebar .sidebar-header{box-sizing:border-box;transition:opacity .35s var(--ease-in-out, ease-in-out),filter .35s var(--ease-in-out, ease-in-out)}#left-sidebar.collapsed #course-navigation,#left-sidebar.collapsed .sidebar-header{opacity:0;filter:blur(4px)}@media (min-width:1025px){#left-sidebar #course-navigation,#left-sidebar .sidebar-header{width:calc(var(--sidebar-width) - 2rem)}}@media (max-width:1024px){#left-sidebar{width:var(--sidebar-width);min-width:250px;max-width:350px}}@media (max-width:550px){#left-sidebar{width:90vw;min-width:250px;max-width:90vw}}.sidebar-fade-bottom,.sidebar-fade-top{height:0;width:100%;position:sticky;pointer-events:none;z-index:2}.sidebar-fade-top{top:0}.sidebar-fade-top::before{content:'';display:block;height:30px;width:100%;background:radial-gradient(ellipse 100% 50% at center top,rgba(var(--sidebar-bg-rgb),.95) 0,rgba(var(--sidebar-bg-rgb),.8) 30%,rgba(var(--sidebar-bg-rgb),.4) 60%,transparent 100%),linear-gradient(180deg,var(--sidebar-bg) 0,rgba(var(--sidebar-bg-rgb),.6) 70%,transparent 100%)}.sidebar-fade-bottom{bottom:0}.sidebar-fade-bottom::before{content:'';display:block;height:30px;width:100%;background:radial-gradient(ellipse 100% 50% at center bottom,rgba(var(--sidebar-bg-rgb),.95) 0,rgba(var(--sidebar-bg-rgb),.8) 30%,rgba(var(--sidebar-bg-rgb),.4) 60%,transparent 100%),linear-gradient(0deg,var(--sidebar-bg) 0,rgba(var(--sidebar-bg-rgb),.6) 70%,transparent 100%)}#left-sidebar:not(.collapsed){border-right:1px solid var(--border-color)}#bottom-control-bar{grid-area:controls;background-color:var(--control-bar-bg);border-top:1px solid var(--border-color);height:var(--control-bar-height,60px);position:sticky;bottom:0;z-index:110;box-shadow:0 0 -2px 10px rgba(0,0,0,.05);overflow-x:hidden}.control-bar-container{max-width:100%;margin:0 auto;height:100%;display:flex;justify-content:space-between;align-items:center;padding:0 var(--spacing-md)}.lesson-controls{display:flex;align-items:center;gap:var(--spacing-sm)}.lesson-completion-status{font-size:var(--text-md);font-weight:500;line-height:normal;border-radius:var(--bttn-radius);display:inline-flex;align-items:center;gap:.5rem;transition:all .3s ease;cursor:default}.lesson-completion-status.in-progress{color:var(--text-secondary-color)}.lesson-completion-status.completed{color:var(--active-green);border:1px solid rgba(0,210,0,.2);background-color:rgba(0,210,0,.05);padding:.5rem 1rem}.single-course-view{max-width:1200px;margin:0 auto;padding:var(--spacing-lg);overflow-x:hidden;box-sizing:border-box}.single-course-view .single-course-view-header{text-align:center;position:relative}.single-course-view .single-course-view-title{margin-bottom:var(--spacing-md);color:var(--text-primary);line-height:2rem;font-size:var(--text-xxl);letter-spacing:var(--ls-base)}.single-course-view .single-course-view-meta{display:flex;justify-content:center;align-items:center;flex-wrap:wrap;gap:var(--spacing-md);color:var(--text-secondary)}.single-course-view .course-meta-item{display:flex;align-items:center;font-size:var(--text-base);gap:var(--spacing-xs)}.single-course-view .single-course-view-meta .bttn{font-size:var(--text-md)}.single-course-view .course-action-buttons{display:flex;gap:var(--spacing-xs)}.single-course-view .single-course-view-modules{margin-top:3rem}.single-course-view .single-course-view-modules .modules-section-title{display:block;font-size:var(--text-lg);font-weight:400;margin-bottom:var(--spacing-md);color:var(--text-tertiary-color);letter-spacing:var(--ls-base);text-align:left}.single-course-view .modules-list{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--spacing-lg);margin-top:var(--spacing-xl)}.single-course-view .single-course-view-module{background:var(--card-bg);border-radius:var(--radius-md);corner-shape:squircle;display:flex;flex-direction:column;justify-content:space-between;overflow:hidden;position:relative;box-shadow:var(--card-shadow);padding:var(--spacing-md);min-height:150px}.single-course-view .module-number-row{display:flex;align-items:center;gap:.7rem;margin-bottom:1rem}.single-course-view .module-number-badge{background:0 0;border:1.5px solid var(--shadow-border);color:var(--text-primary-color);width:2.5rem;height:2.5rem;border-radius:var(--radius-lg);corner-shape:squircle;display:flex;align-items:center;justify-content:center;flex-shrink:0}.single-course-view .single-course-view-module.completed .module-number-badge{border-color:var(--success-color)}.single-course-view .single-course-view-module.in-progress .module-number-badge{border-color:#fb9800}.single-course-view .single-course-view-module.not-started .module-number-badge{color:var(--text-tertiary-color)}.single-course-view .module-number{font-size:var(--text-lg);font-weight:600;line-height:1}.single-course-view .module-status{font-size:var(--text-xs);font-weight:500;letter-spacing:var(--ls-lg);text-transform:uppercase}.single-course-view .single-course-view-module.completed .module-status{color:var(--success-color)}.single-course-view .single-course-view-module.in-progress .module-status{color:#fb9800}.single-course-view .single-course-view-module .module-meta-line{display:flex;align-items:center;gap:var(--spacing-xs);font-size:var(--text-sm);color:var(--text-tertiary-color);margin-bottom:var(--spacing-md)}.single-course-view-module .module-header{display:flex;flex-direction:column;margin-bottom:auto}.single-course-view .single-course-view-module .module-title{font-size:var(--text-lg);color:var(--text-primary);line-height:1.6;font-weight:500;margin:0;margin-bottom:var(--spacing-xs)}.single-course-view .single-course-view-module .module-actions{display:flex;flex-direction:column;gap:10px;margin-top:var(--spacing-lg)}.single-course-view .single-course-view-module .module-actions .bttn{width:100%}@media (max-width:768px){.single-course-view .modules-list{grid-template-columns:1fr;gap:var(--spacing-md)}.single-course-view{max-width:100%;padding:var(--spacing-md)}.single-course-view .single-course-view-meta{flex-direction:column;gap:var(--spacing-sm)}}@media (max-width:1024px) and (min-width:769px){.single-course-view .modules-list{grid-template-columns:repeat(2,1fr)}}@keyframes shimmer{0%{background-position:-200px 0}100%{background-position:calc(200px + 100%) 0}}.skeleton{background:linear-gradient(90deg,var(--skeleton-base) 25%,var(--skeleton-highlight) 50%,var(--skeleton-base) 75%);background-size:200px 100%;animation:shimmer 1.8s ease-in-out infinite;border-radius:var(--radius-lg);corner-shape:squircle}.module-skeleton{margin-bottom:1.5rem;padding:1rem;background:var(--background-color);border-radius:.75rem;border:1px solid rgba(0,0,0,.06)}.module-skeleton-header{display:flex;align-items:center;gap:.75rem;margin-bottom:1rem}.module-skeleton-icon{width:16px;height:16px;border-radius:50%;flex-shrink:0}.module-skeleton-title{height:18px;width:65%}.module-skeleton-progress{height:6px;width:100%;margin-bottom:.75rem;border-radius:3px}.module-skeleton-lessons{display:flex;flex-direction:column;gap:.5rem}.lesson-skeleton{display:flex;align-items:center;gap:.75rem;padding:.5rem 0}.lesson-skeleton-icon{width:14px;height:14px;border-radius:50%;flex-shrink:0}.lesson-skeleton-title{height:14px;flex:1}.lesson-skeleton-duration{height:12px;width:32px;flex-shrink:0}.nav-skeleton{padding:1rem}.nav-skeleton-search{height:36px;width:100%;margin-bottom:1.5rem}.nav-skeleton-section{margin-bottom:2rem}.nav-skeleton-section:last-child{margin-bottom:0}.nav-skeleton-heading{height:16px;width:50%;margin-bottom:1rem}.nav-skeleton-section .lesson-skeleton:nth-child(n+4){display:none}.content-skeleton{padding:0;margin:0;max-width:800px;width:100%;box-sizing:border-box}#main-layout.left-collapsed .content-skeleton{margin:0 auto!important}.content-skeleton-header{margin-bottom:3.5rem}.content-skeleton-title{height:3rem;width:70%;margin-bottom:1.5rem}.content-skeleton-meta{margin-bottom:1rem;display:flex;gap:8px}.content-skeleton-tag{padding:6px 8px;height:1.8rem;width:90px;border-radius:var(--radius-xs);corner-shape:squircle}.content-skeleton-body{margin-bottom:2rem}.content-skeleton-paragraph{height:2rem;margin-bottom:1.5rem}.content-skeleton-paragraph:last-child{margin-bottom:0}.content-skeleton-image{border-radius:var(--radius-sm);corner-shape:squircle;margin:2.5rem 0!important}.progress-skeleton{display:flex;align-items:center;gap:.75rem}.progress-skeleton-bar{height:8px;width:180px}.progress-skeleton-text{height:14px;width:70px}.skeleton-container{position:relative;overflow:hidden}.skeleton{position:relative}.skeleton::before{content:'Loading...';position:absolute;left:-10000px;top:auto;width:1px;height:1px;overflow:hidden}@media (prefers-reduced-motion:reduce){.skeleton{animation:none;background:var(--skeleton-base)}}.nav-skeleton{padding:0}.nav-module-skeleton{margin-bottom:2.5rem!important}.nav-module-skeleton .module-header{display:flex;align-items:center}.nav-module-skeleton .module-toggle{margin-right:.75rem;display:flex;flex-shrink:0;width:2.2rem;height:2.2rem}.nav-module-skeleton .module-toggle .skeleton{width:2.2rem;height:2.2rem}.nav-module-skeleton .module-info{flex-grow:1;min-width:0}.nav-module-skeleton .module-title{margin:0;min-height:2.2rem}.nav-module-skeleton .module-title .skeleton{width:100%}.nav-module-skeleton .module-lessons{padding-left:20px;display:block!important;overflow:hidden;transition:var(--lesson-transition);background:var(--lesson-bg)}.nav-lesson-skeleton{padding:.69rem;border-radius:var(--radius-lg);corner-shape:squircle;position:relative}.nav-lesson-skeleton .lesson-title-row{display:flex;align-items:center;width:100%;min-width:0;margin:0;gap:.5rem}.nav-lesson-skeleton .lesson-progress-indicator .skeleton{flex-shrink:0;width:1.5rem;height:1.5rem;display:flex;border-radius:50%;align-items:center;justify-content:center;margin-right:1rem}.nav-lesson-skeleton .lesson-title{flex:1;min-height:1.8rem}.nav-lesson-skeleton .lesson-title .skeleton{display:block}.nav-module-skeleton .skeleton{min-height:inherit}.nav-lesson-skeleton .skeleton{min-height:inherit}.content-skeleton-image,.content-skeleton-paragraph,.content-skeleton-tag,.content-skeleton-title,.lesson-progress-skeleton,.lesson-skeleton-duration,.lesson-skeleton-icon,.lesson-skeleton-title,.lesson-title-skeleton,.module-skeleton-icon,.module-skeleton-progress,.module-skeleton-title,.module-title-skeleton,.module-toggle-skeleton,.nav-skeleton-heading,.nav-skeleton-search,.progress-skeleton-bar,.progress-skeleton-text{background:linear-gradient(90deg,var(--skeleton-base) 25%,var(--skeleton-highlight) 50%,var(--skeleton-base) 75%);background-size:200px 100%;animation:shimmer 1.8s ease-in-out infinite}.content-skeleton .skeleton:not(:last-child){margin-bottom:1rem}.content-skeleton-body>.skeleton:not(:last-child){margin-bottom:1rem}.nav-module-lessons-skeleton{padding:0;padding-left:20px}.nav-lesson-skeleton-item{padding:.69rem;margin-bottom:var(--spacing-xs);border-radius:var(--radius-lg);corner-shape:squircle;background:0 0;border:1px solid transparent}.nav-lesson-skeleton-item:last-child{margin-bottom:0}.nav-lesson-skeleton-item .lesson-title-row{display:flex;align-items:center;width:100%;min-width:0}.nav-lesson-skeleton-bar{display:inline-block;height:28px;width:100%;margin-left:0;background:linear-gradient(90deg,var(--skeleton-base) 25%,var(--skeleton-highlight) 50%,var(--skeleton-base) 75%);background-size:200px 100%;animation:shimmer 1.8s ease-in-out infinite;font-size:var(--text-md);line-height:2}.single-course-skeleton{max-width:1200px;margin:0 auto;padding:var(--spacing-lg);overflow-x:hidden;box-sizing:border-box}.single-course-skeleton-header{text-align:center;position:relative;margin-bottom:3rem}.single-course-skeleton-title{height:32px;width:60%;margin:0 auto var(--spacing-md) auto}.single-course-skeleton-meta{display:flex;justify-content:center;align-items:center;flex-wrap:wrap;gap:var(--spacing-md);margin-bottom:1rem}.single-course-skeleton-meta-item{height:16px;width:150px}.single-course-skeleton-actions{display:flex;gap:var(--spacing-xs);justify-content:center}.single-course-skeleton-button{width:40px;height:40px}.single-course-skeleton-modules{margin-top:3rem}.single-course-skeleton-section-title{height:20px;width:45%;margin-bottom:var(--spacing-sm);text-align:left}.single-course-skeleton-modules-list{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--spacing-lg);margin-top:var(--spacing-xl)}.single-course-skeleton-module-card{border-radius:var(--radius-md);corner-shape:squircle;display:flex;flex-direction:column;justify-content:space-between;overflow:hidden;position:relative;box-shadow:0 1px 0 2px var(--shadow-border);padding:var(--spacing-md);min-height:150px;background:var(--background-color)}.single-course-skeleton-module-badge{background:0 0;border:1px solid var(--shadow-border);width:2.2rem;height:2.2rem;border-radius:var(--radius-lg);corner-shape:squircle;margin-bottom:1rem;background:var(--skeleton-base)!important;animation:none!important}.single-course-skeleton-module-header{display:flex;flex-direction:column;margin-bottom:auto}.single-course-skeleton-module-title{height:20px;width:85%;margin-bottom:var(--spacing-sm)}.single-course-skeleton-module-meta{display:flex;align-items:center;gap:var(--spacing-xs);margin-bottom:var(--spacing-sm)}.single-course-skeleton-module-meta-item{height:14px}.single-course-skeleton-module-meta-item:first-child{width:70px}.single-course-skeleton-module-meta-item:nth-child(2){width:8px;height:8px;border-radius:50%}.single-course-skeleton-module-meta-item:last-child{width:80px}.single-course-skeleton-module-actions{display:flex;flex-direction:column;gap:10px;margin-top:var(--spacing-lg)}.single-course-skeleton-action-button{height:40px;width:100%}@media (max-width:768px){.single-course-skeleton{max-width:100%;padding:var(--spacing-md)}.single-course-skeleton-modules-list{grid-template-columns:1fr;gap:var(--spacing-md)}.single-course-skeleton-meta{flex-direction:column;gap:var(--spacing-sm)}}@media (max-width:1024px) and (min-width:769px){.single-course-skeleton-modules-list{grid-template-columns:repeat(2,1fr)}}.module-view-skeleton{max-width:960px;margin:0 auto;padding:var(--spacing-lg) var(--spacing-md);overflow-x:hidden;background-color:var(--content-bg)}.module-view-skeleton-header{text-align:center;margin-bottom:var(--spacing-sm);position:relative}.module-view-skeleton-status{display:inline-block;height:20px;width:100px;margin-bottom:var(--spacing-sm);border-radius:6px}.module-view-skeleton-title{height:2.5rem;width:60%;margin:0 auto var(--spacing-md) auto}.module-view-skeleton-actions{display:flex;justify-content:center;gap:10px;margin-bottom:var(--spacing-sm);flex-wrap:wrap}.module-view-skeleton-primary-btn{height:47px;width:180px}.module-view-skeleton-action-buttons{display:flex;gap:var(--spacing-xs)}.module-view-skeleton-action-btn{width:47px;height:47px}.module-view-skeleton-lessons{margin-top:5rem}.module-view-skeleton-section-title{height:2rem;width:50%;margin-bottom:var(--spacing-sm);text-align:left}.module-view-skeleton-lessons-list{display:flex;flex-direction:column;gap:var(--spacing-md)}.module-view-skeleton-lesson-card{position:relative;border-radius:var(--radius-md);corner-shape:squircle;padding:var(--spacing-md);display:grid;grid-template-columns:auto 1fr auto;grid-template-areas:"number content actions";gap:var(--spacing-sm) var(--spacing-md);align-items:center;border:solid var(--shadow-border);border-width:1px 1px 1px 3px;overflow:hidden;background:var(--background-color)}.module-view-skeleton-lesson-number{grid-area:number;width:38px;height:38px;border-radius:var(--radius-lg);corner-shape:squircle;flex-shrink:0;align-self:center;background:var(--skeleton-base)!important;animation:none!important;box-shadow:0 2px 4px rgba(0,0,0,.1)}.module-view-skeleton-lesson-content{grid-area:content;min-width:0;display:flex;flex-direction:column;justify-content:center}.module-view-skeleton-lesson-status{height:1.5rem;width:120px;margin-bottom:1rem}.module-view-skeleton-lesson-title{height:1.5rem;width:70%;margin-bottom:var(--spacing-sm)}.module-view-skeleton-lesson-description{height:1.25rem;width:90%}.module-view-skeleton-lesson-actions{grid-area:actions;flex-shrink:0;justify-self:end;align-self:center;display:flex;gap:var(--spacing-xs)}.module-view-skeleton-lesson-btn{height:40px;width:80px}@media (max-width:768px){.module-view-skeleton{padding:var(--spacing-md) var(--spacing-sm)}.module-view-skeleton-lesson-card{grid-template-columns:auto 1fr;grid-template-areas:"number content" ". actions"}.module-view-skeleton-lesson-number{align-self:center}.module-view-skeleton-lesson-actions{justify-self:stretch;justify-content:center}.module-view-skeleton-lesson-btn{width:100px}}@media (max-width:480px){.module-view-skeleton-title{width:85%}.module-view-skeleton-lesson-card{grid-template-columns:1fr;grid-template-areas:"number" "content" "actions";text-align:center}.module-view-skeleton-lesson-number{justify-self:center;margin-bottom:var(--spacing-xs)}.module-view-skeleton-lesson-actions{margin-top:var(--spacing-sm);justify-content:center}}.courses-view-skeleton{width:100%;height:100%}.courses-skeleton-container{max-width:1400px;margin:0 auto;width:100%}.courses-skeleton-header{text-align:center}.courses-skeleton-title{height:3.5rem;width:350px;margin:0 auto 1.5rem auto}.courses-skeleton-subtitle{height:2rem;width:90vw;max-width:550px;margin:0 auto}.courses-skeleton-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(275px,1fr));gap:var(--spacing-md);margin-top:3rem}.courses-skeleton-card{background-color:var(--sidebar-background);border-radius:var(--radius-md);corner-shape:squircle;overflow:hidden;display:flex;flex-direction:column;height:100%;min-height:400px;border:1px solid var(--border-color);position:relative;box-shadow:0 2px 8px rgba(0,0,0,.04)}.courses-skeleton-thumbnail{width:100%;height:180px;background-color:var(--border-color);background:var(--border-color)!important;animation:none!important}.courses-skeleton-status-badge{position:absolute;top:var(--spacing-sm);right:var(--spacing-sm);width:70px;height:20px;z-index:2}.courses-skeleton-body{padding:var(--spacing-md);display:flex;flex-direction:column;flex-grow:1}.courses-skeleton-course-title{height:28px;width:85%;margin-bottom:var(--spacing-sm)}.courses-skeleton-meta{display:flex;flex-wrap:wrap;align-items:center;gap:var(--spacing-md);margin-bottom:var(--spacing-sm);font-size:.9375rem}.courses-skeleton-meta-icon{width:24px;height:24px;border-radius:50%;flex-shrink:0}.courses-skeleton-circular-progress{width:24px;height:24px;border-radius:50%;flex-shrink:0}.courses-skeleton-footer{display:flex;flex-direction:column;gap:var(--spacing-sm);margin-top:auto}.courses-skeleton-actions{display:flex;gap:var(--spacing-xs)}.courses-skeleton-action-btn{height:40px;width:100%}@media (max-width:768px){.courses-skeleton-card{max-width:none}.courses-skeleton-header{text-align:left}.courses-skeleton-title{margin-left:0}.courses-skeleton-subtitle{margin-left:0}}h1,h2,h3,h4,h5,h6{font-family:Geist,-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Oxygen,Ubuntu,Cantarell,'Open Sans','Helvetica Neue',sans-serif}body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Oxygen,Ubuntu,Cantarell,'Open Sans','Helvetica Neue',sans-serif;color:var(--text-primary)}h1{font-size:clamp(1.8rem, 4vw, 2.2rem);font-weight:600;letter-spacing:var(--ls-xs);margin-top:.5rem}h2{font-size:clamp(1.5rem, 3.5vw, 1.8rem);font-weight:600;letter-spacing:var(--ls-sm)}h3{font-size:clamp(1.15rem, 2.5vw, 1.3rem);font-weight:600}h4{font-size:clamp(1.05rem, 2.25vw, 1.15rem);font-weight:500;display:flex;align-items:center;gap:1rem}h5{font-size:clamp(1rem, 2vw, 1.1rem);font-weight:500}h6{font-size:clamp(.9rem, 1.8vw, 1rem);font-weight:500;text-transform:uppercase;letter-spacing:.05em}