*{margin:0;padding:0;box-sizing:border-box}:root{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;font-size:14px;line-height:1.4;color:#333;background:#f0f0f0}body{margin:0;min-height:100vh;overflow:hidden}#root{height:100vh;width:100vw}.app-layout{display:flex;flex-direction:column;height:100vh;width:100vw;overflow:hidden}.app-body{display:flex;flex:1;overflow:hidden}.app-center{flex:1;display:flex;flex-direction:column;position:relative;overflow:hidden}.canvas-container{flex:1;overflow:hidden;position:relative}.schematic-canvas{display:block;width:100%;height:100%}.toolbar{display:flex;align-items:center;gap:4px;padding:4px 8px;background:#fff;border-bottom:1px solid #ddd;height:40px;flex-shrink:0}.toolbar-title{font-weight:700;font-size:14px;color:#1a1a2e;white-space:nowrap}.toolbar-group{display:flex;align-items:center;gap:2px}.toolbar-divider{width:1px;height:24px;background:#ddd;margin:0 4px}.toolbar-spacer{flex:1}.toolbar-btn{padding:4px 10px;border:1px solid #ddd;border-radius:4px;background:#fff;cursor:pointer;font-size:12px;color:#333;white-space:nowrap;transition:all .15s}.toolbar-btn:hover{background:#f0f0f0;border-color:#bbb}.toolbar-btn.active{background:#e3f2fd;border-color:#2196f3;color:#1565c0}.toolbar-btn.danger{color:#d32f2f}.toolbar-btn.danger:hover{background:#ffebee;border-color:#d32f2f}.toolbar-zoom{font-size:11px;color:#666;min-width:36px;text-align:center}.sidebar{width:160px;background:#fff;border-right:1px solid #ddd;overflow-y:auto;flex-shrink:0}.sidebar-header{padding:8px 12px;font-weight:700;font-size:12px;text-transform:uppercase;color:#666;border-bottom:1px solid #eee}.sidebar-category{border-bottom:1px solid #eee}.category-label{padding:6px 12px 2px;font-size:10px;font-weight:600;text-transform:uppercase;color:#999}.component-list{padding:2px 4px 4px}.component-btn{display:flex;align-items:center;gap:6px;width:100%;padding:4px 8px;border:1px solid transparent;border-radius:4px;background:none;cursor:pointer;font-size:12px;color:#333;text-align:left;transition:all .15s}.component-btn:hover{background:#f5f5f5;border-color:#ddd}.component-btn.active{background:#e3f2fd;border-color:#2196f3;color:#1565c0}.component-icon{display:inline-flex;align-items:center;justify-content:center;width:22px;height:22px;border-radius:3px;background:#f0f0f0;font-size:12px;font-weight:600;color:#555;flex-shrink:0}.sidebar-divider{height:1px;background:#ddd;margin:4px 0}.global-values{padding:4px 12px 8px}.global-value-row{display:flex;flex-direction:column;gap:2px;margin-bottom:6px}.global-value-row label{font-size:11px;color:#666}.global-value-row input{width:100%;padding:4px 6px;border:1px solid #ddd;border-radius:3px;font-size:12px;box-sizing:border-box}.global-value-row input:focus{outline:none;border-color:#2196f3}.right-panel-resize-handle{width:5px;cursor:col-resize;background:transparent;flex-shrink:0;position:relative;z-index:10;transition:background .15s}.right-panel-resize-handle:hover,.right-panel-resize-handle:active{background:#2196f3}.right-panel{width:320px;background:#fff;border-left:1px solid #ddd;display:flex;flex-direction:column;overflow-y:auto;flex-shrink:0}.right-panel-tabs{display:flex;border-bottom:1px solid #ddd}.tab-btn{flex:1;padding:6px 4px;border:none;border-bottom:2px solid transparent;background:none;cursor:pointer;font-size:11px;color:#666;transition:all .15s}.tab-btn:hover{background:#f5f5f5}.tab-btn.active{color:#1565c0;border-bottom-color:#2196f3}.property-panel,.simulation-panel,.problem-panel{padding:0;flex:1}.panel-header{padding:8px 12px;font-weight:700;font-size:12px;text-transform:uppercase;color:#666;border-bottom:1px solid #eee}.panel-empty{padding:16px 12px;color:#999;font-size:12px;text-align:center}.property-content,.sim-content,.problem-controls,.problem-content{padding:8px 12px}.property-row,.sim-row{display:flex;flex-direction:column;gap:2px;margin-bottom:8px}.property-row label,.sim-row label{font-size:11px;font-weight:600;color:#666}.property-row input,.property-row select,.sim-row input,.sim-row select{padding:4px 8px;border:1px solid #ddd;border-radius:4px;font-size:12px;background:#fff;color:#333}.property-row input:focus,.sim-row input:focus{outline:none;border-color:#2196f3;box-shadow:0 0 0 2px #2196f326}.property-value{font-size:12px;color:#333;padding:4px 0}.property-divider{height:1px;background:#eee;margin:8px 0}.property-hint{font-size:10px;color:#999;padding:4px 0;line-height:1.4}.sim-run-btn{width:100%;padding:8px;border:none;border-radius:4px;background:#1565c0;color:#fff;font-size:13px;font-weight:600;cursor:pointer;transition:background .15s;margin-top:4px}.sim-run-btn:hover{background:#0d47a1}.sim-run-btn:disabled{background:#90caf9;cursor:not-allowed}.sim-error{margin-top:8px;padding:8px;background:#ffebee;border:1px solid #ffcdd2;border-radius:4px;color:#c62828;font-size:11px;white-space:pre-wrap}.bottom-panel{border-top:2px solid #ddd;background:#fff;display:flex;flex-direction:column;overflow:hidden;position:relative}.bottom-panel-resize-handle{position:absolute;top:-3px;left:0;right:0;height:6px;cursor:row-resize;z-index:10;background:transparent}.bottom-panel-resize-handle:hover{background:#2196f34d}.bottom-panel-header{display:flex;justify-content:space-between;align-items:center;padding:4px 12px;background:#f5f5f5;border-bottom:1px solid #ddd;font-size:12px;font-weight:600}.close-btn{border:none;background:none;cursor:pointer;font-size:16px;color:#666;padding:0 4px}.show-results-btn{position:absolute;bottom:0;left:50%;transform:translate(-50%);padding:4px 16px;border:1px solid #ddd;border-bottom:none;border-radius:4px 4px 0 0;background:#fff;cursor:pointer;font-size:11px;color:#666;z-index:10}.show-results-btn:hover{background:#f5f5f5}.results-panel{display:flex;flex-direction:column;height:100%;overflow:hidden}.scope-display{display:flex;flex-direction:column;height:100%;padding:8px}.scope-empty{color:#999;text-align:center;padding:24px;font-size:12px;line-height:1.6}.scope-screen{flex:1;min-height:0;border-radius:4px;overflow:hidden;background:#0a1a0a}.scope-svg{width:100%;height:100%}.scope-legend{display:flex;gap:16px;padding:6px 0 0;font-size:11px;font-family:monospace}.scope-legend-item{font-weight:600}.results-tabs{display:flex;border-bottom:1px solid #ddd;flex-shrink:0}.results-tab{flex:1;padding:6px 12px;border:none;border-bottom:2px solid transparent;background:none;cursor:pointer;font-size:12px;color:#666}.results-tab:hover{background:#f5f5f5}.results-tab.active{color:#1565c0;border-bottom-color:#2196f3}.results-content{flex:1;overflow-y:auto;padding:8px 12px}.results-empty{padding:20px;color:#999;text-align:center;font-size:12px}.results-section{margin-bottom:12px}.results-section h3{font-size:12px;font-weight:700;color:#555;margin-bottom:4px}.results-table{width:100%;border-collapse:collapse;font-size:12px}.results-table th{text-align:left;padding:4px 8px;background:#f5f5f5;font-weight:600;color:#666;border-bottom:1px solid #ddd}.results-table td{padding:4px 8px;border-bottom:1px solid #eee}.results-info{font-size:11px;color:#666;font-style:italic;margin-top:8px}.steps-view{display:flex;flex-direction:column;gap:8px}.step-card{border:1px solid #e0e0e0;border-radius:6px;overflow:hidden}.step-header{display:flex;align-items:center;gap:8px;padding:8px 12px;background:#f5f5f5;cursor:pointer;-webkit-user-select:none;user-select:none}.step-header:hover{background:#eee}.step-number{font-size:11px;font-weight:700;color:#1565c0;white-space:nowrap}.step-title{flex:1;font-size:12px;font-weight:600;color:#333}.step-toggle{font-size:10px;color:#999}.step-body{padding:8px 12px}.step-line{font-size:12px;color:#555;margin-bottom:2px}.step-equations{margin:8px 0;padding:8px 12px;background:#fafafa;border-left:3px solid #2196F3;border-radius:0 4px 4px 0}.step-equation{font-family:Courier New,monospace;font-size:12px;color:#333;margin-bottom:4px}.step-results{margin-top:8px;padding:8px;background:#e8f5e9;border-radius:4px}.step-result{font-size:12px;color:#2e7d32;margin-bottom:2px}.problem-title{font-size:14px;font-weight:700;color:#333;margin-bottom:4px}.problem-desc{font-size:12px;color:#555;margin-bottom:8px;line-height:1.5}.problem-questions{margin:8px 0}.problem-question{margin-bottom:8px}.problem-question label{display:block;font-size:12px;font-weight:600;color:#333;margin-bottom:4px}.answer-row{display:flex;align-items:center;gap:4px}.answer-row input{flex:1;padding:4px 8px;border:1px solid #ddd;border-radius:4px;font-size:12px}.answer-row input.correct{border-color:#4caf50;background:#e8f5e9}.answer-row input.incorrect{border-color:#f44336;background:#ffebee}.unit-label{font-size:11px;color:#666;min-width:30px}.check-mark{font-size:11px;color:#4caf50;font-weight:600}.wrong-mark{font-size:11px;color:#f44336}.problem-actions{display:flex;gap:4px;margin-top:8px}.problem-actions .sim-run-btn{flex:1}.problem-actions .toolbar-btn{flex:1;text-align:center}.problem-solution{margin-top:12px;padding:12px;background:#fff3e0;border:1px solid #ffe0b2;border-radius:4px}.problem-solution h4{font-size:12px;font-weight:700;color:#e65100;margin-bottom:8px}.hint{font-size:12px;color:#555;margin-bottom:4px}.solution-answers{margin-top:8px}.solution-answer{font-size:12px;color:#333;margin-bottom:4px}.steps-banner{margin-top:8px;padding:8px 12px;background:#e3f2fd;border:1px solid #bbdefb;border-radius:4px;color:#1565c0;font-size:12px;font-weight:600;cursor:pointer;text-align:center;transition:background .15s}.steps-banner:hover{background:#bbdefb}.steps-info{margin-top:8px;padding:8px;font-size:11px;color:#999;font-style:italic}.sim-step-btn{margin-top:4px;background:#2e7d32}.sim-step-btn:hover{background:#1b5e20}.sim-divider{height:1px;background:#eee;margin:12px 0}.sim-section-header{font-size:12px;font-weight:700;color:#666;text-transform:uppercase;margin-bottom:8px}.sim-thev-btn{background:#6a1b9a}.sim-thev-btn:hover{background:#4a148c}.plots-container{width:100%}.tutorial-overlay{position:fixed;inset:0;z-index:10000;pointer-events:auto}.tutorial-backdrop{position:absolute;inset:0}.tutorial-backdrop-solid{width:100%;height:100%;background:#00000080}.tutorial-spotlight-svg{position:absolute;top:0;left:0;pointer-events:none}.tutorial-tooltip{background:#fff;border-radius:12px;box-shadow:0 8px 32px #0003;padding:16px 20px;max-width:360px;min-width:260px;z-index:10001;animation:tutorial-fade-in .2s ease-out}@keyframes tutorial-fade-in{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.tutorial-tooltip-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px}.tutorial-step-indicator{font-size:11px;color:#999;font-weight:600}.tutorial-skip-btn{border:none;background:none;color:#999;font-size:11px;cursor:pointer;padding:2px 6px}.tutorial-skip-btn:hover{color:#666}.tutorial-title{margin:0 0 8px;font-size:16px;font-weight:700;color:#1a1a2e}.tutorial-content{margin:0 0 16px;font-size:13px;line-height:1.5;color:#555}.tutorial-actions{display:flex;gap:8px;justify-content:flex-end}.tutorial-back-btn{padding:6px 16px;border:1px solid #ddd;border-radius:6px;background:#fff;color:#666;font-size:12px;font-weight:600;cursor:pointer}.tutorial-next-btn{padding:6px 20px;border:none;border-radius:6px;background:#1565c0;color:#fff;font-size:12px;font-weight:600;cursor:pointer;transition:background .15s}.tutorial-next-btn:hover{background:#0d47a1}.help-btn{color:#1565c0;font-weight:600}.marker-btn.active{background:#fff3e0;border-color:#ff9800;color:#e65100}.lesson-list-panel{flex:1;overflow-y:auto}.lesson-domain-tabs{display:flex;border-bottom:1px solid #e0e0e0;padding:0 8px;gap:2px}.lesson-domain-tab{flex:1;padding:8px 4px;border:none;background:none;font-size:12px;font-weight:600;color:#888;cursor:pointer;border-bottom:2px solid transparent;transition:all .15s;display:flex;align-items:center;justify-content:center;gap:4px}.lesson-domain-tab:hover{color:#333;background:#f5f5f5}.lesson-domain-tab.active{color:#1565c0;border-bottom-color:#1565c0}.lesson-domain-count{font-size:10px;font-weight:500;color:#aaa;background:#f0f0f0;padding:1px 5px;border-radius:8px}.lesson-domain-tab.active .lesson-domain-count{color:#1565c0;background:#e3f2fd}.lesson-empty-state{padding:24px;text-align:center;color:#999;font-size:12px}.lesson-list{padding:8px;display:flex;flex-direction:column;gap:8px}.lesson-card{border:1px solid #e0e0e0;border-radius:8px;padding:12px;cursor:pointer;transition:all .15s}.lesson-card:hover{border-color:#2196f3;background:#f8fbff}.lesson-card.completed{border-color:#4caf50;background:#f1f8e9}.lesson-card-header{display:flex;align-items:center;gap:8px;margin-bottom:4px}.lesson-number{width:22px;height:22px;border-radius:50%;background:#1565c0;color:#fff;font-size:11px;font-weight:700;display:flex;align-items:center;justify-content:center;flex-shrink:0}.lesson-card.completed .lesson-number{background:#4caf50}.lesson-title{font-size:13px;font-weight:700;color:#333;flex:1}.lesson-badge{font-size:10px;font-weight:600;color:#4caf50;background:#e8f5e9;padding:2px 6px;border-radius:4px}.lesson-desc{font-size:11px;color:#666;margin-bottom:4px}.lesson-meta{font-size:10px;color:#999}.lesson-panel{flex:1;display:flex;flex-direction:column;overflow:hidden}.lesson-panel-header{display:flex;align-items:center;justify-content:space-between;padding:6px 12px;border-bottom:1px solid #eee}.lesson-back-btn{border:none;background:none;color:#1565c0;cursor:pointer;font-size:12px;font-weight:600;padding:2px 4px}.lesson-progress{font-size:11px;color:#999}.lesson-progress-bar{height:3px;background:#eee;flex-shrink:0}.lesson-progress-fill{height:100%;background:#2196f3;transition:width .3s ease;border-radius:2px}.lesson-step-content{flex:1;overflow-y:auto;padding:12px}.lesson-step-title{font-size:15px;font-weight:700;color:#1a1a2e;margin:0 0 8px}.lesson-text{font-size:12px;line-height:1.6;color:#444}.lesson-text p{margin:0 0 10px;white-space:pre-line}.lesson-pop-text{margin:12px 0;padding:10px 14px;background:#e3f2fd;border:1px solid #bbdefb;border-left:4px solid #2196F3;border-radius:4px;font-size:12px;font-weight:600;color:#1565c0;position:relative}.lesson-highlight-hint{font-size:11px;color:#ff9800;font-style:italic;margin-top:8px}.lesson-action-hint{margin:10px 0;padding:8px 12px;background:#fff3e0;border:1px solid #ffe0b2;border-radius:4px;font-size:12px;color:#e65100}.lesson-circuit-loaded{margin-top:8px;font-size:11px;color:#4caf50;font-weight:600}.lesson-quiz{margin-top:12px}.lesson-quiz-question{font-family:Courier New,monospace;font-size:12px;color:#333;background:#f5f5f5;padding:8px 12px;border-radius:4px;margin-bottom:8px}.lesson-quiz-options{display:flex;flex-direction:column;gap:6px}.lesson-quiz-option{padding:8px 12px;border:1px solid #ddd;border-radius:6px;background:#fff;cursor:pointer;font-size:12px;color:#333;text-align:left;transition:all .15s}.lesson-quiz-option:hover:not(:disabled){border-color:#2196f3;background:#f8fbff}.lesson-quiz-option.selected{border-color:#2196f3;background:#e3f2fd}.lesson-quiz-option.correct{border-color:#4caf50;background:#e8f5e9;color:#2e7d32}.lesson-quiz-option.incorrect{border-color:#f44336;background:#ffebee;color:#c62828}.lesson-quiz-feedback{margin-top:8px;font-size:12px;font-weight:600;padding:6px 10px;border-radius:4px}.lesson-quiz-feedback.correct{background:#e8f5e9;color:#2e7d32}.lesson-quiz-feedback.incorrect{background:#ffebee;color:#c62828}.lesson-nav{display:flex;gap:8px;padding:8px 12px;border-top:1px solid #eee;justify-content:flex-end}.lesson-nav-btn{padding:6px 16px;border:1px solid #ddd;border-radius:6px;background:#fff;color:#666;font-size:12px;font-weight:600;cursor:pointer}.lesson-nav-btn.primary{background:#1565c0;color:#fff;border-color:#1565c0}.lesson-nav-btn.primary:hover{background:#0d47a1}.lesson-nav-btn.primary:disabled{background:#90caf9;border-color:#90caf9;cursor:not-allowed}.lesson-back-link{border:none;background:none;color:#1565c0;cursor:pointer;font-size:12px;text-decoration:underline;margin-top:8px}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:#ccc;border-radius:3px}::-webkit-scrollbar-thumb:hover{background:#aaa}.plot-controls{display:flex;align-items:center;gap:6px;padding:6px 8px;border-bottom:1px solid #e0e0e0;background:#fafafa}.plot-controls label{font-size:12px;color:#666;margin-right:4px}.plot-mode-btn{padding:3px 10px;font-size:11px;border:1px solid #ccc;border-radius:3px;background:#fff;cursor:pointer;color:#333}.plot-mode-btn.active{background:#2196f3;color:#fff;border-color:#1976d2}.plot-mode-btn:hover:not(.active){background:#e3f2fd}.thev-info{font-size:12px;color:#555;padding:8px 0;line-height:1.5}.thev-results{margin-top:12px;border:1px solid #4caf50;border-radius:6px;padding:10px;background:#f1f8e9}.thev-result-header{font-weight:600;font-size:13px;color:#2e7d32;margin-bottom:8px}.thev-result-row{display:flex;justify-content:space-between;padding:4px 0;font-size:12px;border-bottom:1px solid #c8e6c9}.thev-result-row:last-of-type{border-bottom:none}.thev-result-row strong{color:#1b5e20}.thev-diagram{margin-top:8px;padding:8px;background:#fff;border-radius:4px;font-family:monospace;font-size:11px;white-space:pre;color:#333}.thev-help{margin-top:12px;font-size:11px;color:#666;line-height:1.5}.thev-help strong{color:#333}.thev-help p{margin:4px 0}.bottom-panel-tabs{display:flex;gap:2px}.bottom-tab-btn{padding:4px 12px;border:none;border-bottom:2px solid transparent;background:none;cursor:pointer;font-size:11px;font-weight:600;color:#666;transition:all .15s}.bottom-tab-btn:hover{color:#333}.bottom-tab-btn.active{color:#1565c0;border-bottom-color:#2196f3}.shortcuts-panel{padding:12px 16px;overflow-y:auto;flex:1}.shortcuts-title{font-size:14px;font-weight:700;color:#333;margin-bottom:12px}.shortcuts-group{margin-bottom:12px}.shortcuts-category{font-size:11px;font-weight:600;text-transform:uppercase;color:#999;margin-bottom:4px}.shortcuts-table{width:100%;border-collapse:collapse}.shortcuts-table td{padding:3px 8px;font-size:12px;border-bottom:1px solid #f0f0f0}.shortcut-key kbd{display:inline-block;padding:2px 6px;background:#f5f5f5;border:1px solid #ddd;border-radius:3px;font-size:11px;font-family:Courier New,monospace;min-width:20px;text-align:center}.shortcut-action{color:#555}.domain-toggle{display:flex;padding:4px;gap:2px;background:#f5f5f5;border-bottom:1px solid #ddd}.domain-btn{flex:1;padding:5px 4px;border:1px solid transparent;border-radius:4px;background:transparent;cursor:pointer;font-size:11px;font-weight:600;color:#888;text-align:center;transition:all .15s}.domain-btn:hover{color:#555;background:#eee}.domain-btn.active{background:#fff;color:#1565c0;border-color:#ddd;box-shadow:0 1px 2px #0000000d}.digital-info,.controls-info{padding:8px 12px;font-size:11px;color:#666;line-height:1.5}.digital-info p,.controls-info p{margin:0 0 4px}.sim-section{margin-top:8px;border-top:1px solid #eee;padding-top:8px}.sim-section-header{font-size:11px;font-weight:600;color:#666;margin-bottom:4px;text-transform:uppercase;letter-spacing:.5px}.sim-input-row{display:flex;align-items:center;gap:8px}.digital-toggle{padding:3px 10px;border:1px solid #ccc;border-radius:4px;cursor:pointer;font-size:11px;font-weight:600;font-family:monospace;transition:all .15s}.digital-toggle.high{background:#2979ff;color:#fff;border-color:#1565c0}.digital-toggle.low{background:#455a64;color:#fff;border-color:#37474f}.digital-results{padding:8px 12px;overflow:auto}.digital-cycle-control{display:flex;align-items:center;gap:8px;padding:6px 0;border-bottom:1px solid #eee;margin-bottom:8px}.digital-cycle-control label{font-size:12px;font-weight:600}.digital-cycle-control input[type=range]{flex:1}.cycle-label{font-size:11px;font-family:monospace;color:#666;min-width:50px}.digital-val{font-family:monospace;font-weight:600;font-size:12px}.digital-val.high{color:#2979ff}.digital-val.low{color:#455a64}.digital-val.unknown{color:#ff9800}.controls-results{padding:8px 12px;overflow:auto}.controls-legend{padding:4px 0;font-family:monospace}.power-btn{font-weight:600!important;padding:4px 12px!important}.power-btn.powered{background:#4caf50!important;color:#fff!important;border-color:#388e3c!important}.power-btn:hover:not(:disabled){background:#e8f5e9!important}.power-btn.powered:hover:not(:disabled){background:#43a047!important}