.lesson-sidebar{width:320px;height:100vh;background-color:var(--color-surface);border-right:1px solid rgba(255,255,255,.1);display:flex;flex-direction:column;position:fixed;left:0;top:0;z-index:45;transform:translate(-100%);transition:transform var(--transition-normal);overflow:hidden}.lesson-sidebar.open{transform:translate(0)}@media (min-width: 1024px){.lesson-sidebar{position:sticky;transform:translate(0);z-index:10}}.sidebar-header{padding:var(--space-6) var(--space-4) var(--space-4);border-bottom:1px solid rgba(255,255,255,.05);position:relative;background-color:var(--color-surface-elevated)}.header-content{display:flex;flex-direction:column;gap:var(--space-4)}.sidebar-title{font-size:var(--text-lg);font-weight:700;color:var(--color-text-primary);margin:0;line-height:var(--leading-tight);padding-right:var(--space-8)}.close-button{position:absolute;top:var(--space-4);right:var(--space-4);width:2rem;height:2rem;background:none;border:none;border-radius:var(--radius-md);cursor:pointer;display:flex;align-items:center;justify-content:center;color:var(--color-text-tertiary);transition:all var(--transition-fast)}.close-button:hover{background-color:#ffffff1a;color:var(--color-text-primary)}.close-button:focus{outline:none;box-shadow:var(--shadow-focus)}.close-icon{font-size:var(--text-sm);line-height:1}@media (min-width: 1024px){.close-button{display:none}}.overall-progress{display:flex;align-items:center;gap:var(--space-3)}.progress-circle{position:relative;width:3rem;height:3rem;flex-shrink:0}.progress-svg{width:100%;height:100%;transform:rotate(-90deg)}.progress-circle-bg{fill:none;stroke:var(--color-surface-elevated);stroke-width:2}.progress-circle-fill{fill:none;stroke:var(--color-primary);stroke-width:2;stroke-linecap:round;transition:stroke-dasharray var(--transition-slow)}.progress-text{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);font-size:var(--text-xs);font-weight:600;color:var(--color-text-primary);font-variant-numeric:tabular-nums}.progress-info{display:flex;flex-direction:column;gap:var(--space-1)}.progress-label{font-size:var(--text-sm);color:var(--color-text-primary);font-weight:500}.lesson-count{font-size:var(--text-xs);color:var(--color-text-tertiary)}.lesson-list{flex:1;overflow-y:auto;padding:var(--space-2) 0;display:flex;flex-direction:column;gap:var(--space-1)}.lesson-item{display:flex;align-items:flex-start;gap:var(--space-3);padding:var(--space-3) var(--space-4);border:none;background:none;text-align:left;cursor:pointer;transition:all var(--transition-fast);position:relative;border-radius:0;width:100%}.lesson-item:hover{background-color:#ffffff0d}.lesson-item:focus{outline:none;background-color:#ffffff1a}.lesson-item.selected{background-color:var(--color-primary-muted);border-right:3px solid var(--color-primary)}.lesson-item.selected:hover{background-color:var(--color-primary-muted)}.lesson-number{display:flex;flex-direction:column;align-items:center;gap:var(--space-1);flex-shrink:0;width:2rem}.status-icon{font-size:var(--text-sm);line-height:1;font-weight:600}.number-text{font-size:var(--text-xs);color:var(--color-text-tertiary);font-weight:500;font-variant-numeric:tabular-nums}.lesson-item.selected .number-text{color:var(--color-primary);font-weight:600}.lesson-content{flex:1;min-width:0;display:flex;flex-direction:column;gap:var(--space-1)}.lesson-title{font-size:var(--text-sm);font-weight:600;color:var(--color-text-primary);margin:0;line-height:var(--leading-tight);word-wrap:break-word}.lesson-item.selected .lesson-title{color:var(--color-primary)}.lesson-subtitle{font-size:var(--text-xs);color:var(--color-text-secondary);margin:0;line-height:var(--leading-normal);word-wrap:break-word}.lesson-item.selected .lesson-subtitle{color:var(--color-text-primary)}.lesson-time{display:flex;align-items:center;gap:var(--space-1);font-size:var(--text-xs);color:var(--color-text-tertiary);margin-top:var(--space-1)}.selection-indicator{position:absolute;left:0;top:50%;transform:translateY(-50%);width:3px;height:60%;background-color:var(--color-primary);border-radius:0 2px 2px 0}.indicator-dot{width:100%;height:100%;background-color:var(--color-primary);border-radius:inherit;animation:pulse-indicator 2s infinite}@keyframes pulse-indicator{0%,to{opacity:1}50%{opacity:.6}}.lesson-item.completed{opacity:.8}.lesson-item.current{background-color:var(--color-primary-muted)}.lesson-item.not-started{opacity:.7}.lesson-item.not-started .lesson-title{color:var(--color-text-secondary)}.sidebar-footer{padding:var(--space-4);border-top:1px solid rgba(255,255,255,.05);background-color:var(--color-surface-elevated)}.completion-message{text-align:center}.completion-celebration,.encouragement{display:flex;align-items:center;justify-content:center;gap:var(--space-2);font-size:var(--text-sm);font-weight:500}.completion-celebration{color:var(--color-success)}.encouragement{color:var(--color-text-secondary)}.celebration-icon,.encouragement-icon{font-size:var(--text-base);line-height:1}[data-focus-mode=true] .lesson-sidebar{background-color:var(--color-surface-focus)}[data-focus-mode=true] .sidebar-header{background-color:var(--color-surface-elevated-focus)}[data-focus-mode=true] .indicator-dot{animation:none}[data-focus-mode=true] .time-icon,[data-focus-mode=true] .celebration-icon,[data-focus-mode=true] .encouragement-icon{display:none}.reduce-motion .lesson-item,.reduce-motion .progress-circle-fill,.reduce-motion .indicator-dot{transition:none!important;animation:none!important}.high-contrast .lesson-sidebar{border-right:2px solid var(--color-text-secondary)}.high-contrast .lesson-item.selected{background-color:var(--color-primary);color:#fff}.high-contrast .lesson-item.selected .lesson-title,.high-contrast .lesson-item.selected .lesson-subtitle{color:#fff}@media (max-width: 640px){.lesson-sidebar{width:280px}.sidebar-header{padding:var(--space-4) var(--space-3)}.sidebar-title{font-size:var(--text-base)}.lesson-item{padding:var(--space-2) var(--space-3)}.lesson-title{font-size:var(--text-xs)}.lesson-subtitle{font-size:10px}}.lesson-list::-webkit-scrollbar{width:4px}.lesson-list::-webkit-scrollbar-track{background:transparent}.lesson-list::-webkit-scrollbar-thumb{background-color:var(--color-surface-elevated);border-radius:2px}.lesson-list::-webkit-scrollbar-thumb:hover{background-color:var(--color-text-tertiary)}@media print{.lesson-sidebar{display:none!important}}.pomodoro-timer{width:450px;max-width:calc(100vw - 2rem);background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-xl);box-shadow:var(--shadow-lg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);overflow:hidden}.pomodoro-header{display:flex;align-items:flex-start;justify-content:space-between;padding:var(--space-4);background-color:#ffffff05;border-bottom:1px solid rgba(255,255,255,.05)}.header-main{display:flex;align-items:flex-start;gap:var(--space-4);flex:1}.mode-info{display:flex;align-items:center;gap:var(--space-3)}.mode-icon{font-size:var(--text-2xl);line-height:1}.mode-text{display:flex;flex-direction:column;gap:var(--space-1)}.mode-label{font-size:var(--text-lg);font-weight:600;color:var(--color-text-primary);margin:0}.mode-description{font-size:var(--text-sm);color:var(--color-text-secondary);margin:0;line-height:var(--leading-tight)}.session-stats{display:flex;gap:var(--space-4)}.stat{display:flex;flex-direction:column;align-items:center;gap:var(--space-1)}.stat-number{font-size:var(--text-xl);font-weight:700;color:var(--color-primary);font-variant-numeric:tabular-nums}.stat-label{font-size:var(--text-xs);color:var(--color-text-tertiary);text-transform:uppercase;letter-spacing:.5px}.timer-display{display:flex;justify-content:center;padding:var(--space-8)}.timer-circle{position:relative;width:200px;height:200px}.progress-ring{width:100%;height:100%;transform:rotate(-90deg)}.progress-ring-bg{opacity:.3}.progress-ring-fill{transition:stroke-dasharray var(--transition-normal)}.timer-time{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);font-size:2.5rem;font-weight:700;color:var(--color-text-primary);font-variant-numeric:tabular-nums;text-align:center;font-family:SF Mono,Monaco,Cascadia Code,Roboto Mono,Consolas,Courier New,monospace}.timer-controls{display:flex;justify-content:center;gap:var(--space-4);padding:var(--space-4) var(--space-6) var(--space-6);flex-wrap:wrap}.control-button{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-4) var(--space-6);border:none;border-radius:var(--radius-lg);font-size:var(--text-base);font-weight:600;cursor:pointer;transition:all var(--transition-fast);min-width:100px;justify-content:center;white-space:nowrap}.control-button.primary:focus{box-shadow:var(--shadow-focus)}.control-button.secondary:focus{border-color:var(--color-primary)}.control-button:disabled{opacity:.5;cursor:not-allowed;transform:none!important}.button-icon{font-size:var(--text-base);line-height:1}.quick-settings{padding:var(--space-5) var(--space-6) var(--space-6);border-top:1px solid rgba(255,255,255,.05);background-color:#ffffff05}.quick-settings h4{font-size:var(--text-base);font-weight:600;color:var(--color-text-primary);margin:0 0 var(--space-4) 0}.settings-grid{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-4)}.setting-item label{display:flex;align-items:center;gap:var(--space-3);font-size:var(--text-sm);color:var(--color-text-secondary);cursor:pointer;padding:var(--space-2);border-radius:var(--radius-md);transition:background-color var(--transition-fast)}.setting-item label:hover{background-color:#ffffff0d}.setting-item input[type=checkbox]{width:1.125rem;height:1.125rem;accent-color:var(--color-primary);cursor:pointer}.pomodoro-minimized{position:fixed;bottom:var(--space-4);right:var(--space-4);background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-lg);padding:var(--space-3);cursor:pointer;transition:all var(--transition-fast);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);box-shadow:var(--shadow-md);z-index:40}.pomodoro-minimized:hover{background-color:var(--color-surface-elevated);transform:translateY(-2px);box-shadow:var(--shadow-lg)}.minimized-content{display:flex;align-items:center;gap:var(--space-2);position:relative}.minimized-icon{font-size:var(--text-lg);line-height:1}.minimized-time{font-size:var(--text-sm);font-weight:600;color:var(--color-text-primary);font-variant-numeric:tabular-nums;font-family:SF Mono,Monaco,Cascadia Code,Roboto Mono,Consolas,Courier New,monospace}.minimized-progress{position:absolute;bottom:0;left:0;height:2px;background-color:var(--color-primary);border-radius:1px;transition:width var(--transition-normal)}@media (max-width: 480px){.pomodoro-timer{width:calc(100vw - 2rem)}.pomodoro-header{padding:var(--space-3)}.header-main{flex-direction:column;gap:var(--space-3)}.session-stats{align-self:stretch;justify-content:space-around}.timer-display{padding:var(--space-6)}.timer-circle{width:160px;height:160px}.timer-time{font-size:2rem}.timer-controls{padding:var(--space-4) var(--space-3) var(--space-4);gap:var(--space-3);flex-direction:column}.control-button{padding:var(--space-3) var(--space-4);min-width:120px;width:100%;max-width:200px;margin:0 auto}.settings-grid{grid-template-columns:1fr;gap:var(--space-3)}.quick-settings{padding:var(--space-4) var(--space-3) var(--space-4)}.pomodoro-minimized{bottom:var(--space-3);right:var(--space-3)}}[data-focus-mode=true] .pomodoro-timer{background-color:var(--color-surface-focus)}[data-focus-mode=true] .mode-icon,[data-focus-mode=true] .button-icon,[data-focus-mode=true] .minimized-icon{display:none}.reduce-motion .progress-ring-fill,.reduce-motion .control-button,.reduce-motion .pomodoro-minimized{transition:none!important;animation:none!important;transform:none!important}.high-contrast .pomodoro-timer{border:2px solid var(--color-text-secondary)}@media print{.pomodoro-timer,.pomodoro-minimized{display:none!important}}.breathing-exercise{width:450px;max-width:calc(100vw - 2rem);background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-xl);box-shadow:var(--shadow-lg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);overflow:hidden}.breathing-header{display:flex;align-items:center;justify-content:space-between;padding:var(--space-4);background-color:#ffffff05;border-bottom:1px solid rgba(255,255,255,.05)}.header-main{flex:1}.exercise-title{font-size:var(--text-lg);font-weight:600;color:var(--color-text-primary);margin:0}.exercise-subtitle{font-size:var(--text-sm);color:var(--color-text-secondary);margin:var(--space-1) 0 0 0}.header-actions{display:flex;gap:var(--space-2)}.action-button{display:flex;align-items:center;justify-content:center;width:2rem;height:2rem;background:none;border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);color:var(--color-text-tertiary);cursor:pointer;transition:all var(--transition-fast);font-size:var(--text-sm)}.action-button:hover{background-color:var(--color-surface-elevated);border-color:#fff3;color:var(--color-text-primary)}.action-button:focus{outline:none;box-shadow:var(--shadow-focus)}.pattern-selection{padding:var(--space-4)}.pattern-selection h4{font-size:var(--text-base);font-weight:600;color:var(--color-text-primary);margin:0 0 var(--space-4) 0}.patterns-grid{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-3)}.pattern-card{display:flex;flex-direction:column;gap:var(--space-2);padding:var(--space-3);background-color:var(--color-surface-elevated);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-lg);cursor:pointer;transition:all var(--transition-fast);text-align:left;position:relative}.pattern-card:hover{background-color:var(--color-surface);border-color:#fff3;transform:translateY(-1px)}.pattern-card.selected{background-color:#ffffff0d;transform:translateY(-1px)}.pattern-selection-border{position:absolute;top:-1px;right:-1px;bottom:-1px;left:-1px;border:2px solid;border-radius:var(--radius-lg);pointer-events:none}.pattern-name{font-size:var(--text-sm);font-weight:600;color:var(--color-text-primary)}.pattern-timing{font-size:var(--text-xs);font-weight:600;font-family:SF Mono,Monaco,Cascadia Code,Roboto Mono,Consolas,Courier New,monospace}.pattern-description{font-size:var(--text-xs);color:var(--color-text-tertiary);line-height:var(--leading-tight)}.breathing-guide{display:flex;flex-direction:column;align-items:center;padding:var(--space-8) var(--space-4);gap:var(--space-8)}.breathing-circle{width:140px;height:140px;border-radius:50%;display:flex;align-items:center;justify-content:center;position:relative;opacity:.8;box-shadow:0 0 30px #ffffff1a}.circle-content{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-2);color:#fff;text-shadow:0 1px 3px rgba(0,0,0,.5);height:100%;width:100%;text-align:center}.phase-timer{font-size:var(--text-4xl);font-weight:700;font-variant-numeric:tabular-nums;font-family:SF Mono,Monaco,Cascadia Code,Roboto Mono,Consolas,Courier New,monospace;line-height:1}.phase-name{font-size:var(--text-sm);text-transform:uppercase;letter-spacing:.05em;font-weight:600;line-height:1;margin-top:var(--space-1)}.breathing-instruction{font-size:var(--text-lg);color:var(--color-text-primary);text-align:center;font-weight:500;max-width:300px;line-height:var(--leading-relaxed)}.breathing-progress{display:flex;flex-direction:column;align-items:center;gap:var(--space-3);padding:0 var(--space-4) var(--space-4)}.progress-dots{display:flex;gap:var(--space-2)}.progress-dot{width:.5rem;height:.5rem;border-radius:50%;background-color:var(--color-surface-elevated);transition:all var(--transition-normal)}.progress-dot.completed{background-color:var(--color-success)}.progress-dot.current{background-color:var(--color-primary);animation:pulse-breathing 2s infinite}@keyframes pulse-breathing{0%,to{opacity:1;transform:scale(1)}50%{opacity:.7;transform:scale(1.2)}}.progress-text{font-size:var(--text-sm);color:var(--color-text-secondary);font-weight:500}.breathing-controls{display:flex;flex-direction:column;align-items:center;gap:var(--space-4);padding:var(--space-4)}.rounds-selector label{display:flex;flex-direction:column;align-items:center;gap:var(--space-2);font-size:var(--text-sm);color:var(--color-text-secondary)}.rounds-selector select{background-color:var(--color-surface-elevated);color:var(--color-text-primary);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);padding:var(--space-2) var(--space-3);font-size:var(--text-sm);cursor:pointer}.rounds-selector select:focus{outline:none;border-color:var(--color-primary);box-shadow:var(--shadow-focus)}.control-button{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-3) var(--space-6);border:none;border-radius:var(--radius-lg);font-size:var(--text-base);font-weight:600;cursor:pointer;transition:all var(--transition-fast);justify-content:center;min-width:150px}.control-button.primary{background-color:var(--color-primary);color:#fff}.control-button.primary:hover{background-color:var(--color-primary-subtle);transform:translateY(-1px);box-shadow:var(--shadow-md)}.control-button.secondary{background-color:var(--color-surface-elevated);color:var(--color-text-primary);border:1px solid rgba(255,255,255,.1)}.control-button.secondary:hover{background-color:var(--color-surface);border-color:#fff3}.control-button:focus{outline:none;box-shadow:var(--shadow-focus)}.button-icon{font-size:var(--text-lg);line-height:1}.completion-message{display:flex;flex-direction:column;align-items:center;gap:var(--space-3);padding:var(--space-6);text-align:center;background-color:#22c55e1a;border-top:1px solid rgba(34,197,94,.2)}.completion-icon{font-size:3rem;line-height:1}.completion-message h4{font-size:var(--text-xl);font-weight:600;color:var(--color-success);margin:0}.completion-message p{font-size:var(--text-base);color:var(--color-text-secondary);margin:0;line-height:var(--leading-relaxed);max-width:300px}.breathing-minimized{position:fixed;bottom:var(--space-4);right:calc(var(--space-4) + 80px);background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-lg);padding:var(--space-3);cursor:pointer;transition:all var(--transition-fast);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);box-shadow:var(--shadow-md);z-index:40}.breathing-minimized:hover{background-color:var(--color-surface-elevated);transform:translateY(-2px);box-shadow:var(--shadow-lg)}.minimized-content{display:flex;align-items:center;gap:var(--space-2)}.breathing-indicator{width:1rem;height:1rem;border-radius:50%;transition:transform 1s ease-in-out}.minimized-text{font-size:var(--text-sm);font-weight:500;color:var(--color-text-primary);white-space:nowrap}@media (max-width: 480px){.breathing-exercise{width:calc(100vw - 2rem)}.breathing-header,.pattern-selection{padding:var(--space-3)}.patterns-grid{grid-template-columns:1fr;gap:var(--space-2)}.pattern-card{padding:var(--space-2)}.breathing-guide{padding:var(--space-6) var(--space-3)}.breathing-circle{width:100px;height:100px}.phase-timer{font-size:var(--text-xl)}.breathing-instruction{font-size:var(--text-base)}.control-button{padding:var(--space-3) var(--space-4);min-width:120px}.breathing-minimized{bottom:var(--space-3);right:calc(var(--space-3) + 60px)}}[data-focus-mode=true] .breathing-exercise{background-color:var(--color-surface-focus)}[data-focus-mode=true] .completion-icon,[data-focus-mode=true] .button-icon{display:none}[data-focus-mode=true] .breathing-circle{box-shadow:none}.reduce-motion .breathing-circle,.reduce-motion .control-button,.reduce-motion .breathing-minimized,.reduce-motion .breathing-indicator{transition:none!important;animation:none!important;transform:none!important}.reduce-motion .progress-dot.current{animation:none!important}.high-contrast .breathing-exercise{border:2px solid var(--color-text-secondary)}.high-contrast .pattern-card.selected{border:2px solid var(--color-primary);background-color:var(--color-surface-elevated)}.high-contrast .pattern-selection-border{border-width:3px}.high-contrast .control-button.primary{background-color:var(--color-primary);border:2px solid var(--color-primary)}.high-contrast .control-button.secondary{border:2px solid var(--color-text-secondary)}@media print{.breathing-exercise,.breathing-minimized{display:none!important}}.wellness-navbar{display:flex;align-items:center;gap:1px;background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-lg);padding:var(--space-2);margin:var(--space-4) 0;position:sticky;top:0;z-index:30;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);box-shadow:var(--shadow-sm)}.wellness-navbar.collapsed{display:flex;justify-content:center;padding:var(--space-2);background-color:#ffffff0d;border:1px solid rgba(255,255,255,.05)}.navbar-group{position:relative;display:flex;align-items:center}.navbar-group:not(:last-child):after{content:"";width:1px;height:2rem;background-color:#ffffff1a;margin:0 var(--space-2)}.navbar-group.navbar-toggle:after{display:none}.navbar-button{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-2) var(--space-3);background:none;border:none;border-radius:var(--radius-md);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-fast);font-size:var(--text-sm);font-weight:500;white-space:nowrap}.navbar-button:hover{background-color:var(--color-surface-elevated);color:var(--color-text-primary)}.navbar-button:focus{outline:none;box-shadow:var(--shadow-focus)}.navbar-button.active{background-color:var(--color-primary-muted);color:var(--color-primary)}.button-icon{font-size:var(--text-base);line-height:1;flex-shrink:0}.button-text{font-size:var(--text-sm);font-weight:500}.dropdown-arrow{font-size:var(--text-xs);transition:transform var(--transition-fast);margin-left:var(--space-1)}.navbar-button.active .dropdown-arrow{transform:rotate(180deg)}.hide-button{opacity:.7}.hide-button:hover{opacity:1}.show-navbar-button{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-2) var(--space-4);background-color:var(--color-surface-elevated);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-fast);font-size:var(--text-sm);font-weight:500}.show-navbar-button:hover{background-color:var(--color-surface);color:var(--color-text-primary);border-color:#fff3}.show-navbar-button:focus{outline:none;box-shadow:var(--shadow-focus)}.show-icon{font-size:var(--text-sm);line-height:1}.show-text{font-size:var(--text-sm)}.dropdown-menu{position:absolute;top:calc(100% + var(--space-2));left:0;min-width:280px;background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-lg);box-shadow:var(--shadow-lg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);padding:var(--space-2);z-index:50;animation:dropdownSlide .2s ease-out}@keyframes dropdownSlide{0%{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:translateY(0)}}.dropdown-menu.text-menu{min-width:320px;padding:var(--space-4)}.dropdown-item{display:flex;align-items:center;gap:var(--space-3);width:100%;padding:var(--space-3);background:none;border:none;border-radius:var(--radius-md);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-fast);text-align:left}.dropdown-item:hover{background-color:var(--color-surface-elevated);color:var(--color-text-primary)}.dropdown-item:focus{outline:none;background-color:var(--color-surface-elevated);box-shadow:var(--shadow-focus)}.dropdown-item.active{background-color:var(--color-primary-muted);color:var(--color-primary)}.item-icon{font-size:var(--text-base);line-height:1;flex-shrink:0}.item-content{display:flex;flex-direction:column;gap:var(--space-1);flex:1;min-width:0}.item-title{font-size:var(--text-sm);font-weight:600;color:inherit}.item-description{font-size:var(--text-xs);color:var(--color-text-tertiary);line-height:var(--leading-tight)}.toggle-item{position:relative}.toggle-indicator{font-size:var(--text-sm);font-weight:600;flex-shrink:0;margin-left:var(--space-2)}.toggle-item.active .item-description{color:var(--color-primary)}.menu-section{margin-bottom:var(--space-4)}.menu-section:last-child{margin-bottom:0}.section-title{font-size:var(--text-xs);font-weight:600;color:var(--color-text-primary);text-transform:uppercase;letter-spacing:.025em;margin-bottom:var(--space-3);padding-bottom:var(--space-2);border-bottom:1px solid rgba(255,255,255,.1)}.button-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--space-2);margin-bottom:var(--space-2)}.grid-button{display:flex;align-items:center;justify-content:center;width:100%;height:2.5rem;background-color:var(--color-surface-elevated);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-fast);font-weight:600}.grid-button:hover{background-color:var(--color-surface);border-color:#fff3;color:var(--color-text-primary)}.grid-button:focus{outline:none;box-shadow:var(--shadow-focus)}.grid-button.active{background-color:var(--color-primary);border-color:var(--color-primary);color:#fff}.size-labels{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--space-2)}.size-label{font-size:var(--text-xs);color:var(--color-text-tertiary);text-align:center;font-weight:500}.size-label.active{color:var(--color-primary);font-weight:600}.line-height-demo{font-size:var(--text-sm);color:currentColor;text-align:center}.font-option{padding:var(--space-2) var(--space-3)}.font-option .item-title{font-size:var(--text-sm)}.wellness-overlay{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%);z-index:60}@media (max-width: 640px){.wellness-overlay{top:0;left:0;right:0;bottom:0;transform:none;display:flex;align-items:center;justify-content:center;background-color:#000c;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px)}}@media (max-width: 768px){.wellness-navbar{flex-wrap:wrap;gap:var(--space-1);padding:var(--space-2)}.navbar-group:not(:last-child):after{display:none}.navbar-button{padding:var(--space-2)}.button-text{display:none}.dropdown-menu{min-width:calc(100vw - 2rem);left:50%;transform:translate(-50%)}.dropdown-menu.text-menu{min-width:calc(100vw - 2rem)}.button-grid,.size-labels{grid-template-columns:repeat(2,1fr)}}@media (max-width: 480px){.wellness-navbar{margin:var(--space-2) 0}.navbar-button{padding:var(--space-1)}.button-icon{font-size:var(--text-sm)}.dropdown-arrow{display:none}}[data-focus-mode=true] .wellness-navbar{background-color:var(--color-surface-focus)}[data-focus-mode=true] .button-icon,[data-focus-mode=true] .item-icon,[data-focus-mode=true] 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1024px){.progress-tracker{padding:var(--space-4) var(--space-6)}}.progress-container{position:relative;display:flex;align-items:center;gap:var(--space-3);margin-bottom:var(--space-3)}.progress-track{flex:1;height:.5rem;background-color:var(--color-surface-elevated);border-radius:var(--radius-md);overflow:hidden;position:relative;border:1px solid rgba(255,255,255,.05)}.progress-fill{height:100%;background:linear-gradient(90deg,var(--color-primary),var(--color-secondary));border-radius:var(--radius-md);transition:width var(--transition-slow) ease-out;position:relative}.progress-fill:after{content:"";position:absolute;top:0;right:0;bottom:0;width:20px;background:linear-gradient(90deg,transparent,rgba(255,255,255,.3));animation:shimmer 2s infinite}@keyframes shimmer{0%{transform:translate(-20px);opacity:0}50%{opacity:1}to{transform:translate(20px);opacity:0}}.progress-text{flex-shrink:0}.progress-percentage{font-size:var(--text-sm);font-weight:600;color:var(--color-text-primary);font-variant-numeric:tabular-nums}.progress-details{display:flex;align-items:center;justify-content:space-between;gap:var(--space-4);flex-wrap:wrap}@media (max-width: 640px){.progress-details{flex-direction:column;align-items:flex-start;gap:var(--space-2)}}.lesson-info{flex:1;min-width:0}.lesson-position{display:flex;align-items:center;gap:var(--space-3);margin-bottom:var(--space-1);flex-wrap:wrap}@media (max-width: 640px){.lesson-position{flex-direction:column;align-items:flex-start;gap:var(--space-1)}}.position-text{font-size:var(--text-sm);color:var(--color-text-secondary);font-weight:500;font-variant-numeric:tabular-nums}.progress-message{display:flex;align-items:center;gap:var(--space-2);font-size:var(--text-sm);color:var(--color-text-tertiary)}.message-emoji{font-size:var(--text-base);line-height:1}.current-lesson-title{font-size:var(--text-sm);color:var(--color-text-primary);font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:300px}@media (max-width: 640px){.current-lesson-title{max-width:100%;white-space:normal;overflow:visible;text-overflow:unset}}.time-remaining{display:flex;align-items:center;gap:var(--space-2);background-color:var(--color-surface-elevated);padding:var(--space-2) var(--space-3);border-radius:var(--radius-md);flex-shrink:0}.time-icon{font-size:var(--text-sm);line-height:1}[data-focus-mode=true] .progress-tracker{background-color:var(--color-surface-focus)}[data-focus-mode=true] .progress-fill:after{display:none}[data-focus-mode=true] .message-emoji,[data-focus-mode=true] .time-icon{display:none}.reduce-motion .progress-fill{transition:none!important}.reduce-motion .progress-fill:after{animation:none!important;display:none}.high-contrast .progress-track{border:2px solid var(--color-text-secondary)}.high-contrast .progress-fill{background:var(--color-primary)}@media (max-width: 480px){.progress-tracker{padding:var(--space-2) var(--space-3)}.progress-container{margin-bottom:var(--space-2)}.progress-track{height:.375rem}.progress-percentage,.position-text,.progress-message,.current-lesson-title{font-size:var(--text-xs)}}.progress-tracker.loading .progress-fill{background:var(--color-surface-elevated);animation:pulse 1.5s ease-in-out infinite}@keyframes pulse{0%,to{opacity:.5}50%{opacity:1}}@media (prefers-reduced-motion: reduce){.progress-fill,.progress-fill:after{animation:none!important;transition:none!important}}@media print{.progress-tracker{background:#fff;color:#000;border-bottom:1px solid #ccc;position:static}.progress-fill:after{display:none}}.lesson-layout{min-height:100vh;background-color:var(--color-background);color:var(--color-text-primary);display:flex;flex-direction:column;font-size:var(--text-base);transition:all var(--transition-normal)}.lesson-layout[data-font-size=small]{font-size:var(--text-sm)}.lesson-layout[data-font-size=large]{font-size:var(--text-lg)}.lesson-layout[data-font-size=xl]{font-size:var(--text-xl)}.lesson-layout.focus-mode{background-color:var(--color-background-focus)}.lesson-layout.focus-mode *{animation-duration:0ms!important;transition-duration:.2s!important}.mobile-header{display:flex;align-items:center;gap:var(--space-4);padding:var(--space-4);background-color:var(--color-surface);border-bottom:1px solid rgba(255,255,255,.1);position:sticky;top:0;z-index:30;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}@media (min-width: 1024px){.mobile-header{display:none}}.sidebar-toggle{display:flex;flex-direction:column;justify-content:center;align-items:center;width:2.5rem;height:2.5rem;background:none;border:none;cursor:pointer;padding:var(--space-2);border-radius:var(--radius-md);transition:background-color var(--transition-fast)}.sidebar-toggle:hover{background-color:var(--color-surface-elevated)}.sidebar-toggle:focus{background-color:var(--color-surface-elevated)}.hamburger-line{width:1.25rem;height:2px;background-color:var(--color-text-secondary);transition:all var(--transition-fast);margin:1px 0}.sidebar-toggle:hover .hamburger-line,.sidebar-toggle:focus .hamburger-line{background-color:var(--color-text-primary)}.header-content{flex:1;min-width:0}.header-title{font-size:var(--text-lg);font-weight:600;margin:0;color:var(--color-text-primary);line-height:var(--leading-tight);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.header-lesson{font-size:var(--text-sm);color:var(--color-text-secondary);margin:var(--space-1) 0 0 0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.layout-container{display:flex;flex:1;position:relative}.sidebar-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background-color:#0009;z-index:40;-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px)}@media (min-width: 1024px){.sidebar-overlay{display:none}}.main-content{flex:1;min-width:0;overflow-y:auto;background-color:var(--color-background)}.content-container{max-width:1200px;margin:0 auto;padding:var(--space-6) var(--space-4)}@media (min-width: 640px){.content-container{padding:var(--space-8) var(--space-6)}}@media (min-width: 1024px){.content-container{padding:var(--space-10) var(--space-8)}}.lesson-loading{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:50vh;text-align:center;gap:var(--space-4)}.loading-spinner{width:2rem;height:2rem;border:3px solid var(--color-surface-elevated);border-top:3px solid var(--color-primary);border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.lesson-welcome{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:60vh;text-align:center;max-width:600px;margin:0 auto;gap:var(--space-4)}.welcome-icon{font-size:4rem;margin-bottom:var(--space-2)}@media (min-width: 640px){.welcome-icon{font-size:5rem}}.welcome-title{font-size:var(--text-3xl);font-weight:700;color:var(--color-text-primary);margin:0;line-height:var(--leading-tight)}@media (min-width: 640px){.welcome-title{font-size:var(--text-4xl)}}.welcome-subtitle{font-size:var(--text-lg);color:var(--color-text-secondary);margin:0;line-height:var(--leading-relaxed)}.welcome-time{display:flex;align-items:center;gap:var(--space-2);font-size:var(--text-sm);color:var(--color-text-tertiary);background-color:var(--color-surface);padding:var(--space-2) var(--space-4);border-radius:var(--radius-md)}.time-icon{font-size:var(--text-base)}.welcome-instruction{font-size:var(--text-base);color:var(--color-text-secondary);margin:var(--space-2) 0;line-height:var(--leading-relaxed)}.lesson-error{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:40vh;text-align:center;gap:var(--space-4)}.error-icon{font-size:3rem;color:var(--color-error)}.lesson-error h3{font-size:var(--text-2xl);font-weight:600;color:var(--color-text-primary);margin:0}.lesson-error p{font-size:var(--text-base);color:var(--color-text-secondary);margin:0}.cta-button{background-color:var(--color-primary);color:#fff;border:none;padding:var(--space-3) var(--space-6);border-radius:var(--radius-md);font-size:var(--text-base);font-weight:500;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:var(--space-2)}.cta-button:hover{background-color:var(--color-primary-subtle);transform:translateY(-1px);box-shadow:var(--shadow-md)}.cta-button:focus{transform:translateY(-1px);box-shadow:var(--shadow-focus)}.cta-button:active{transform:translateY(0)}.secondary-button{background-color:var(--color-surface-elevated);color:var(--color-text-primary);border:1px solid var(--color-text-tertiary);padding:var(--space-2) var(--space-4);border-radius:var(--radius-md);font-size:var(--text-sm);font-weight:500;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:var(--space-2)}.secondary-button:hover{background-color:var(--color-surface);border-color:var(--color-text-secondary)}.secondary-button:focus{border-color:var(--color-primary)}.lesson-content{max-width:100%;width:100%}@media (prefers-reduced-motion: reduce){.lesson-layout,.lesson-layout *{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}@media (prefers-contrast: high){.lesson-layout{--color-background: #000000;--color-surface: #111111;--color-text-primary: #ffffff;--color-text-secondary: #e0e0e0}}.lesson-layout :focus-visible{outline:2px solid var(--color-primary);outline-offset:2px}@media print{.mobile-header,.sidebar-overlay{display:none!important}.main-content{margin:0;padding:0}.lesson-layout{background:#fff;color:#000}}.code-block{background-color:var(--color-surface-elevated);border:1px solid 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640px){.path-text{max-width:120px}}.code-title{font-size:var(--text-sm);color:var(--color-text-primary);font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.language-badge{padding:var(--space-1) var(--space-2);background-color:var(--color-primary-muted);color:var(--color-primary);border-radius:var(--radius-sm);font-size:var(--text-xs);font-weight:600;text-transform:uppercase;letter-spacing:.5px}.copy-button{display:flex;align-items:center;gap:var(--space-1);padding:var(--space-2) var(--space-3);background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-fast);font-size:var(--text-xs);font-weight:500}.copy-button:hover{background-color:var(--color-surface-elevated);border-color:#fff3;color:var(--color-text-primary)}.copy-button:focus{outline:none;box-shadow:var(--shadow-focus)}.copy-button.success{background-color:var(--color-success);border-color:var(--color-success);color:#fff}.copy-icon{font-size:var(--text-xs);line-height:1}.copy-text{white-space:nowrap}@media (max-width: 480px){.copy-text{display:none}}.expand-button:hover{background-color:var(--color-surface);border-color:#fff3;color:var(--color-text-primary)}.code-content{transition:all var(--transition-normal);overflow:hidden}.code-content.collapsed{max-height:0;opacity:0}.code-pre{margin:0;padding:var(--space-4);background:none;color:var(--color-text-primary);font-size:var(--text-sm);line-height:var(--leading-relaxed);overflow-x:auto;white-space:pre;-moz-tab-size:2;tab-size:2}.code-pre:focus{outline:none;box-shadow:inset 0 0 0 2px var(--color-primary)}.code-text{font-family:inherit;font-size:inherit;line-height:inherit}.code-line{display:flex;align-items:flex-start;min-height:1.5em}.code-line.highlighted{background-color:#3b82f61a;margin:0 calc(var(--space-4) * -1);padding:0 var(--space-4)}.line-number{display:inline-block;width:3em;flex-shrink:0;color:var(--color-text-muted);text-align:right;margin-right:var(--space-3);-webkit-user-select:none;user-select:none;font-variant-numeric:tabular-nums}.line-content{flex:1;white-space:pre}.code-pre .keyword{color:#ff7b72;font-weight:600}.code-pre .string{color:#a5d6ff}.code-pre .comment{color:#8b949e;font-style:italic}.code-pre .number{color:#79c0ff}.code-pre .function{color:#d2a8ff}.code-pre .class-name{color:#ffa657}.code-pre .operator{color:#ff7b72}.code-pre .punctuation{color:var(--color-text-secondary)}.code-pre .property{color:#79c0ff}.code-pre .annotation{color:#ffa657}.code-pre.language-kotlin .keyword{color:#ff7b72}.code-pre.language-kotlin .function{color:#d2a8ff}.code-pre.language-kotlin .string{color:#a5d6ff}@media (max-width: 768px){.code-header{padding:var(--space-2) var(--space-3);flex-wrap:wrap}.header-info{order:1;flex:1 1 100%;margin-bottom:var(--space-2)}.header-actions{order:2}.code-pre{padding:var(--space-3);font-size:var(--text-xs)}}@media (max-width: 480px){.code-header{padding:var(--space-2)}.header-info{gap:var(--space-2)}.path-text{max-width:80px}.code-title{display:none}.code-pre{padding:var(--space-2)}}[data-focus-mode=true] .code-block{background-color:var(--color-surface-elevated-focus)}[data-focus-mode=true] .code-header{background-color:var(--color-surface-focus)}[data-focus-mode=true] .path-icon,[data-focus-mode=true] .copy-icon{display:none}[data-focus-mode=true] .language-badge{background-color:var(--color-surface-elevated-focus);color:var(--color-text-secondary)}.reduce-motion .code-content,.reduce-motion .expand-icon,.reduce-motion .copy-button{transition:none!important;animation:none!important}.high-contrast .code-block{border:2px solid var(--color-text-secondary)}.high-contrast .code-header{background-color:var(--color-surface-elevated);border-bottom:2px solid var(--color-text-tertiary)}.high-contrast .code-pre{background-color:var(--color-background)}.high-contrast .code-pre .keyword{color:#fff;font-weight:700}.high-contrast .code-pre .string{color:#0f0}.high-contrast .code-pre .comment{color:#888}.code-pre::-webkit-scrollbar{height:8px}.code-pre::-webkit-scrollbar-track{background:var(--color-surface);border-radius:var(--radius-sm)}.code-pre::-webkit-scrollbar-thumb{background:var(--color-text-muted);border-radius:var(--radius-sm)}.code-pre::-webkit-scrollbar-thumb:hover{background:var(--color-text-tertiary)}@media print{.code-block{background:#fff;border:1px solid #ccc;break-inside:avoid}.code-header{background:#f5f5f5;border-bottom:1px solid #ccc}.copy-button,.expand-button{display:none}.code-content.collapsed{max-height:none;opacity:1}.code-pre{background:#fff;color:#000}.code-pre .keyword{color:#000;font-weight:700}.code-pre .string{color:#555}.code-pre .comment{color:#888}}.lesson-card{background-color:var(--color-surface);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-xl);overflow:hidden;transition:all var(--transition-normal);margin-bottom:var(--space-6);position:relative}.lesson-card:hover{border-color:#fff3;box-shadow:var(--shadow-lg);transform:translateY(-2px)}.lesson-card:focus-within{border-color:var(--color-primary);box-shadow:var(--shadow-focus)}.lesson-card--concept{border-left:4px solid var(--color-primary);background:linear-gradient(135deg,var(--color-primary-muted),var(--color-surface))}.lesson-card--practice{border-left:4px solid var(--color-secondary);background:linear-gradient(135deg,var(--color-secondary-muted),var(--color-surface))}.lesson-card--example{border-left:4px solid var(--color-accent);background:linear-gradient(135deg,var(--color-accent-muted),var(--color-surface))}.lesson-card--important{border-left:4px solid var(--color-warning);background:linear-gradient(135deg,rgba(245,158,11,.1),var(--color-surface))}.lesson-card--warning{border-left:4px solid var(--color-error);background:linear-gradient(135deg,rgba(239,68,68,.1),var(--color-surface))}.lesson-card--success{border-left:4px solid var(--color-success);background:linear-gradient(135deg,rgba(34,197,94,.1),var(--color-surface))}.lesson-card__header{display:flex;align-items:flex-start;justify-content:space-between;gap:var(--space-4);padding:var(--space-5) var(--space-6) var(--space-4);background-color:#ffffff05;border-bottom:1px solid rgba(255,255,255,.05)}.header-main{display:flex;align-items:flex-start;gap:var(--space-4);flex:1;min-width:0}.card-icon{display:flex;align-items:center;justify-content:center;width:3rem;height:3rem;background-color:var(--color-surface-elevated);border-radius:var(--radius-lg);font-size:var(--text-xl);flex-shrink:0;border:1px solid rgba(255,255,255,.1)}.title-section{flex:1;min-width:0}.card-title{font-size:var(--text-xl);font-weight:700;color:var(--color-text-primary);margin:0;line-height:var(--leading-tight);word-wrap:break-word}.card-subtitle{font-size:var(--text-sm);color:var(--color-text-secondary);margin:var(--space-2) 0 0 0;line-height:var(--leading-relaxed);word-wrap:break-word}.header-metadata{display:flex;align-items:center;gap:var(--space-3);flex-shrink:0}.difficulty-indicator{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-1) var(--space-2);background-color:var(--color-surface-elevated);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.1)}.difficulty-dot{width:.375rem;height:.375rem;border-radius:50%;transition:background-color var(--transition-fast)}.difficulty-label{font-size:var(--text-xs);color:var(--color-text-tertiary);font-weight:500;white-space:nowrap}.time-estimate{display:flex;align-items:center;gap:var(--space-1);padding:var(--space-1) var(--space-2);background-color:var(--color-surface-elevated);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.1)}.time-icon{font-size:var(--text-xs);line-height:1}.time-text{font-size:var(--text-xs);color:var(--color-text-tertiary);font-weight:500;white-space:nowrap}.expand-button{display:flex;align-items:center;justify-content:center;width:2rem;height:2rem;background:none;border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);color:var(--color-text-tertiary)}.expand-button:hover{background-color:var(--color-surface-elevated);border-color:#fff3;color:var(--color-text-primary)}.expand-button:focus{outline:none;box-shadow:var(--shadow-focus)}.expand-icon{font-size:var(--text-xs);transition:transform var(--transition-fast);line-height:1}.expand-icon.expanded{transform:rotate(180deg)}.lesson-card__content{transition:all var(--transition-normal);overflow:hidden}.lesson-card__content.collapsed{max-height:0;opacity:0}.content-wrapper{padding:var(--space-5) var(--space-6) var(--space-6)}.lesson-card__content p{color:var(--color-text-secondary);line-height:inherit;margin-bottom:var(--space-4);font-family:inherit}.lesson-card__content p:last-child{margin-bottom:0}.lesson-card__content h4{color:var(--color-text-primary);font-size:var(--text-lg);font-weight:600;margin:var(--space-6) 0 var(--space-3) 0;line-height:var(--leading-tight);font-family:inherit}.lesson-card__content h4:first-child{margin-top:0}.lesson-card__content h5{color:var(--color-text-primary);font-size:var(--text-base);font-weight:600;margin:var(--space-4) 0 var(--space-2) 0;line-height:var(--leading-tight);font-family:inherit}.lesson-card__content ul,.lesson-card__content ol{color:var(--color-text-secondary);line-height:inherit;margin:var(--space-4) 0;padding-left:var(--space-6);font-family:inherit}.lesson-card__content li{margin-bottom:var(--space-2);font-family:inherit;line-height:inherit}.lesson-card__content code{background-color:var(--color-surface-elevated);color:var(--color-accent);padding:var(--space-1) var(--space-2);border-radius:var(--radius-sm);font-size:.9em;font-family:SF Mono,Monaco,Cascadia Code,Roboto Mono,Consolas,Courier New,monospace}.lesson-card__content strong{color:var(--color-text-primary);font-weight:600}.lesson-card__content em{color:var(--color-text-primary);font-style:italic}@media (max-width: 768px){.lesson-card__header{padding:var(--space-4) var(--space-4) var(--space-3)}.content-wrapper{padding:var(--space-4) var(--space-4) var(--space-5)}.card-title{font-size:var(--text-lg)}.card-icon{width:2.5rem;height:2.5rem;font-size:var(--text-lg)}.header-metadata{flex-direction:column;gap:var(--space-2);align-items:flex-end}}@media (max-width: 480px){.lesson-card__header{flex-direction:column;align-items:flex-start;gap:var(--space-3)}.header-metadata{flex-direction:row;align-items:center;align-self:stretch;justify-content:space-between}.difficulty-label{display:none}.time-text{font-size:10px}}[data-focus-mode=true] .lesson-card{background-color:var(--color-surface-focus);border-color:#ffffff0d}[data-focus-mode=true] .lesson-card:hover{transform:none;box-shadow:var(--shadow-md)}[data-focus-mode=true] .lesson-card--concept,[data-focus-mode=true] .lesson-card--practice,[data-focus-mode=true] .lesson-card--example,[data-focus-mode=true] .lesson-card--important,[data-focus-mode=true] .lesson-card--warning,[data-focus-mode=true] .lesson-card--success{background:var(--color-surface-focus)}[data-focus-mode=true] .time-icon{display:none}.reduce-motion .lesson-card,.reduce-motion .expand-icon,.reduce-motion .lesson-card__content{transition:none!important;animation:none!important}.reduce-motion .lesson-card:hover{transform:none}.high-contrast .lesson-card{border:2px solid var(--color-text-secondary)}.high-contrast .lesson-card__header{background-color:var(--color-surface-elevated);border-bottom:2px solid var(--color-text-tertiary)}.high-contrast .card-title{color:var(--color-text-primary)}@media print{.lesson-card{background:#fff;color:#000;border:1px solid #ccc;break-inside:avoid;margin-bottom:1rem}.lesson-card__header{background:#f5f5f5;border-bottom:1px solid #ccc}.expand-button{display:none}.lesson-card__content.collapsed{max-height:none;opacity:1}}