:root,[data-theme=light]{--bg-darker:#fff;--bg-dark:#fff;--bg-card:#fff;--bg-card-hover:#f9fafb;--bg-input:#fff;--border-color:#e5e7eb;--border-hover:#d1d5db;--border-focus:#da291c;--text-main:#111827;--text-muted:#4b5563;--text-dim:#9ca3af;--primary:#da291c;--primary-hover:#b91c1c;--primary-glow:#da291c26;--primary-tint:#da291c0f;--accent-purple:#da291c;--accent-green:#059669;--accent-green-bg:#0596691a;--accent-red:#da291c;--accent-red-bg:#da291c14;--accent-amber:#d97706;--accent-amber-bg:#d977061a;--btn-accent-bg:#111827;--btn-accent-color:#fff;--btn-accent-hover:#1f2937;--radius-sm:6px;--radius-md:10px;--radius-lg:14px;--shadow:0 4px 20px #0000000f;--shadow-hover:0 8px 26px #0000001a;--font:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;--font-mono:"SF Mono", Menlo, Monaco, Consolas, "Courier New", monospace}[data-theme=dark]{--bg-darker:#0a0b0e;--bg-dark:#111317;--bg-card:#181b22;--bg-card-hover:#222631;--bg-input:#0e1015;--border-color:#282d38;--border-hover:#3e4556;--border-focus:#da291c;--text-main:#fff;--text-muted:#9ca3af;--text-dim:#6b7280;--primary:#da291c;--primary-hover:#b91c1c;--primary-glow:#da291c38;--primary-tint:#da291c14;--accent-purple:#da291c;--accent-green:#10b981;--accent-green-bg:#10b9811f;--accent-red:#da291c;--accent-red-bg:#da291c1f;--accent-amber:#f59e0b;--accent-amber-bg:#f59e0b1f;--btn-accent-bg:#fff;--btn-accent-color:#0a0b0e;--btn-accent-hover:#f3f4f6;--shadow:0 8px 30px #0009;--shadow-hover:0 12px 36px #000000b3}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font);background-color:var(--bg-dark);color:var(--text-main);-webkit-font-smoothing:antialiased;width:100%;min-height:100vh;margin:0;padding:0;transition:background-color .2s,color .2s;overflow-x:hidden}#root{width:100%;min-height:100vh;display:flex}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--bg-darker)}::-webkit-scrollbar-thumb{background:var(--border-color);border-radius:4px}::-webkit-scrollbar-thumb:hover{background:var(--primary)}#app-container,#app-root,.app-container{flex-direction:row;flex:1;width:100%;min-height:100vh;display:flex}#sidebar{background-color:var(--bg-darker);border-right:1px solid var(--border-color);z-index:50;flex-direction:column;flex-shrink:0;width:270px;height:100vh;transition:all .25s;display:flex;position:sticky;top:0}.brand-section{border-bottom:1px solid var(--border-color);padding:24px 20px}.brand-title{color:var(--text-main);letter-spacing:-.02em;align-items:center;gap:12px;font-size:1.18rem;font-weight:800;display:flex}.brand-icon{background:var(--primary);border-radius:var(--radius-sm);color:#fff;letter-spacing:-.05em;flex-shrink:0;justify-content:center;align-items:center;width:34px;height:34px;font-size:1.1rem;font-weight:900;display:flex;box-shadow:0 0 14px #da291c66}.brand-badge{text-transform:uppercase;color:var(--primary);letter-spacing:.04em;background:#da291c14;border:1px solid #da291c4d;border-radius:999px;margin-top:8px;padding:3px 9px;font-size:.72rem;font-weight:700;display:inline-block}.nav-menu{flex:1;padding:16px 12px;list-style:none;overflow-y:auto}.nav-header{text-transform:uppercase;color:var(--text-dim);letter-spacing:.06em;padding:14px 12px 6px;font-size:.72rem;font-weight:800}.nav-item{border-radius:var(--radius-md);color:var(--text-muted);cursor:pointer;border-left:3px solid #0000;align-items:center;gap:12px;margin-bottom:4px;padding:10px 14px;font-size:.92rem;font-weight:600;text-decoration:none;transition:all .15s;display:flex}.nav-item:hover{background-color:var(--bg-card-hover);color:var(--text-main)}.nav-item.active{color:var(--primary);border-left:3px solid var(--primary);background:linear-gradient(90deg,#da291c1f,#0000);font-weight:700}.nav-badge{border-radius:var(--radius-sm);background:var(--border-color);color:var(--text-muted);margin-left:auto;padding:3px 8px;font-size:.72rem;font-weight:700}.sidebar-footer{border-top:1px solid var(--border-color);background-color:var(--bg-darker);padding:16px}.subscription-card{background-color:var(--bg-card);border-radius:var(--radius-md);box-shadow:var(--shadow);border:1px solid #da291c59;padding:14px}.sub-status-row{justify-content:space-between;align-items:center;margin-bottom:6px;display:flex}.sub-plan-badge{text-transform:uppercase;border-radius:999px;padding:3px 8px;font-size:.75rem;font-weight:800}.plan-free{color:var(--text-muted);border:1px solid var(--border-color);background:#9ca3af26}.plan-pro{background:var(--primary);color:#fff;box-shadow:0 0 10px #da291c59}.sub-upgrade-btn{background:var(--primary);color:#fff;border-radius:var(--radius-sm);cursor:pointer;border:none;width:100%;margin-top:10px;padding:9px 12px;font-size:.82rem;font-weight:800;transition:all .2s;box-shadow:0 2px 10px #da291c4d}.sub-upgrade-btn:hover{background:var(--primary-hover);transform:translateY(-1px);box-shadow:0 4px 16px #da291c73}#main-content{background-color:var(--bg-dark);flex-direction:column;flex:1;min-width:0;min-height:100vh;display:flex;overflow-y:auto}#topbar{border-bottom:1px solid var(--border-color);background-color:var(--bg-darker);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);z-index:40;justify-content:space-between;align-items:center;height:64px;padding:0 32px;transition:background-color .2s,border-color .2s;display:flex;position:sticky;top:0}.topbar-left{align-items:center;gap:16px;display:flex}.topbar-title{color:var(--text-main);letter-spacing:-.01em;font-size:1.15rem;font-weight:800}.topbar-right{align-items:center;gap:12px;display:flex}.theme-toggle-container{background-color:var(--bg-card-hover);border:1px solid var(--border-color);border-radius:999px;align-items:center;gap:2px;padding:3px;display:inline-flex}.theme-toggle-btn{color:var(--text-muted);cursor:pointer;-webkit-user-select:none;user-select:none;background:0 0;border:none;border-radius:999px;align-items:center;gap:5px;padding:5px 10px;font-size:.78rem;font-weight:700;transition:all .18s;display:inline-flex}.theme-toggle-btn:hover{color:var(--text-main)}.theme-toggle-btn.active{background-color:var(--primary);color:#fff;box-shadow:0 2px 8px #da291c59}.theme-icon{font-size:.85rem;line-height:1}@media (width<=768px){.theme-label{display:none}.theme-toggle-btn{padding:5px 8px}}.btn{border-radius:var(--radius-md);cursor:pointer;-webkit-user-select:none;user-select:none;border:1px solid #0000;justify-content:center;align-items:center;gap:8px;padding:9px 18px;font-size:.88rem;font-weight:700;transition:all .2s;display:inline-flex}.btn-primary{background-color:var(--primary);color:#fff;border-color:var(--primary);box-shadow:0 2px 8px #da291c40}.btn-primary:hover{background-color:var(--primary-hover);border-color:var(--primary-hover);transform:translateY(-1px);box-shadow:0 4px 16px #da291c66}.btn-secondary{background-color:var(--bg-card);color:var(--text-main);border-color:var(--border-color)}.btn-secondary:hover{background-color:var(--bg-card-hover);border-color:var(--border-hover)}.btn-accent{background-color:var(--btn-accent-bg);color:var(--btn-accent-color);border-color:var(--btn-accent-bg);box-shadow:var(--shadow);font-weight:800}.btn-accent:hover{background-color:var(--btn-accent-hover);border-color:var(--btn-accent-hover);transform:translateY(-1px)}.btn-sm{padding:6px 14px;font-size:.82rem}.btn-danger{background-color:var(--accent-red);color:#fff;border-color:var(--accent-red)}.btn-danger:hover{background-color:#b91c1c;border-color:#b91c1c}.page-view{width:100%;max-width:1200px;margin:0 auto;padding:32px}.stats-grid{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:20px;margin-bottom:32px;display:grid}.stat-card{background-color:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);box-shadow:var(--shadow);flex-direction:column;gap:8px;padding:24px;transition:border-color .2s,transform .2s,box-shadow .2s;display:flex}.stat-card:hover{box-shadow:var(--shadow-hover);border-color:#da291c66;transform:translateY(-2px)}.stat-header{color:var(--text-muted);text-transform:uppercase;letter-spacing:.04em;justify-content:space-between;align-items:center;font-size:.82rem;font-weight:700;display:flex}.stat-value{color:var(--text-main);letter-spacing:-.02em;font-size:2.2rem;font-weight:900}.stat-subtext{color:var(--text-dim);font-size:.8rem}.banner-pro{background:var(--bg-card);border:1px solid var(--border-color);border-left:5px solid var(--primary);border-radius:var(--radius-lg);color:var(--text-main);box-shadow:var(--shadow);justify-content:space-between;align-items:center;gap:24px;margin-bottom:28px;padding:24px 28px;transition:all .2s;display:flex}[data-theme=light] .banner-pro{border-color:#e5e7eb;border-left-color:var(--primary);color:var(--text-main);background:linear-gradient(135deg,#da291c0a,#fff)}[data-theme=dark] .banner-pro{background:linear-gradient(135deg, #da291c14, var(--bg-card));border-color:var(--border-color);border-left-color:var(--primary);color:#fff}.banner-title{color:var(--text-main);align-items:center;gap:10px;margin-bottom:6px;font-size:1.3rem;font-weight:800;display:flex}.banner-desc{color:var(--text-muted);max-width:680px;font-size:.92rem;line-height:1.5}.section-title-row{justify-content:space-between;align-items:center;margin-bottom:20px;display:flex}.section-title{color:var(--text-main);align-items:center;gap:10px;font-size:1.25rem;font-weight:800;display:flex}.cards-grid{grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:20px;margin-bottom:36px;display:grid}.chapter-card{background-color:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);box-shadow:var(--shadow);cursor:pointer;flex-direction:column;gap:14px;padding:24px;transition:transform .2s,border-color .2s,box-shadow .2s;display:flex}.chapter-card:hover{border-color:var(--primary);box-shadow:var(--shadow-hover);transform:translateY(-2px)}.chapter-badge-row{justify-content:space-between;align-items:center;display:flex}.domain-pill{color:var(--primary);letter-spacing:.04em;background:#da291c1a;border:1px solid #da291c40;border-radius:999px;padding:4px 10px;font-size:.75rem;font-weight:800}.weight-badge{color:var(--accent-amber);font-size:.75rem;font-weight:700}.chapter-title{color:var(--text-main);font-size:1.1rem;font-weight:700;line-height:1.4}.chapter-meta{color:var(--text-muted);gap:16px;font-size:.85rem;display:flex}.modal-overlay{-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);z-index:100;background-color:#000000bf;justify-content:center;align-items:center;padding:20px;display:flex;position:fixed;inset:0}.modal-card{background-color:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);width:100%;max-width:580px;max-height:90vh;box-shadow:var(--shadow);color:var(--text-main);padding:32px;overflow-y:auto}.modal-header{justify-content:space-between;align-items:flex-start;margin-bottom:24px;display:flex}.modal-close{color:var(--text-muted);cursor:pointer;background:0 0;border:none;font-size:1.5rem;transition:color 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64px);display:flex}.test-top-bar,.test-header{background-color:var(--bg-darker);border-bottom:1px solid var(--border-color);justify-content:space-between;align-items:center;padding:14px 32px;display:flex}.test-progress-info{align-items:center;gap:20px;display:flex}.timer-box,.timer-badge{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-md);font-family:var(--font-mono);color:var(--text-main);align-items:center;gap:8px;padding:6px 14px;font-size:1rem;font-weight:700;display:flex}.timer-warning{border-color:var(--primary);color:var(--primary);background:#da291c1a}.flag-btn{border:1px solid var(--border-color);color:var(--text-muted);border-radius:var(--radius-md);cursor:pointer;background:0 0;align-items:center;gap:6px;padding:6px 14px;font-size:.85rem;font-weight:600;transition:all .15s;display:flex}.flag-btn:hover{border-color:var(--text-muted);color:var(--text-main)}.flag-btn.flagged{border-color:var(--accent-amber);color:var(--accent-amber);background:var(--accent-amber-bg)}.test-body{flex:1;width:100%;max-width:900px;margin:0 auto;padding:32px}.question-meta-row{color:var(--text-muted);justify-content:space-between;align-items:center;margin-bottom:16px;font-size:.85rem;display:flex}.question-text{color:var(--text-main);margin-bottom:28px;font-size:1.18rem;font-weight:700;line-height:1.6}.options-list{flex-direction:column;gap:12px;margin-bottom:32px;display:flex}.option-item,.option-card{background-color:var(--bg-card);border:2px solid var(--border-color);border-radius:var(--radius-md);cursor:pointer;-webkit-user-select:none;user-select:none;box-shadow:var(--shadow);align-items:flex-start;gap:16px;padding:16px 20px;transition:all .15s;display:flex}.option-item:hover,.option-card:hover{background-color:var(--bg-card-hover);border-color:#da291c73}.option-item.selected,.option-card.selected{border-color:var(--primary);background-color:#da291c0f}.option-item.struck,.option-card.struck{opacity:.45;text-decoration:line-through}.option-marker,.option-radio{border:2px solid var(--border-color);width:28px;height:28px;color:var(--text-muted);border-radius:999px;flex-shrink:0;justify-content:center;align-items:center;font-size:.85rem;font-weight:800;transition:all .15s;display:flex}.option-item.selected .option-marker,.option-card.selected .option-radio{background-color:var(--primary);border-color:var(--primary);color:#fff}.option-item.correct,.option-card.correct{border-color:var(--accent-green)!important;background-color:var(--accent-green-bg)!important}.option-item.incorrect,.option-card.incorrect{border-color:var(--primary)!important;background-color:var(--accent-red-bg)!important}.option-label,.option-text{color:var(--text-main);flex:1;font-size:.98rem;line-height:1.5}.strike-toggle,.strike-btn{border:1px solid var(--border-color);border-radius:var(--radius-sm);color:var(--text-dim);cursor:pointer;background:0 0;padding:3px 8px;font-size:.75rem;transition:all .15s}.strike-toggle:hover,.strike-btn:hover{color:var(--text-main);border-color:var(--text-muted)}.explanation-box,.feedback-card{background-color:var(--bg-card);border:1px solid var(--border-color);border-left:4px solid var(--primary);border-radius:var(--radius-md);box-shadow:var(--shadow);margin-top:24px;padding:20px}.explanation-title,.feedback-title{color:var(--primary);align-items:center;gap:8px;margin-bottom:8px;font-size:.95rem;font-weight:800;display:flex}.explanation-text,.feedback-explanation{color:var(--text-main);margin-bottom:12px;font-size:.92rem;line-height:1.6}.distractor-text,.feedback-distractors{color:var(--text-muted);border-top:1px solid var(--border-color);padding-top:10px;font-size:.85rem;line-height:1.5}.test-bottom-bar,.test-footer{background-color:var(--bg-darker);border-top:1px solid var(--border-color);justify-content:space-between;align-items:center;padding:16px 32px;display:flex}.nav-grid-panel{background-color:var(--bg-card-hover);border-radius:var(--radius-md);grid-template-columns:repeat(auto-fill,minmax(38px,1fr));gap:8px;max-height:240px;margin-bottom:24px;padding:16px;display:grid;overflow-y:auto}.grid-q-btn{aspect-ratio:1;border-radius:var(--radius-sm);background-color:var(--bg-card);border:1px solid var(--border-color);color:var(--text-muted);cursor:pointer;justify-content:center;align-items:center;font-size:.85rem;font-weight:800;transition:all .15s;display:flex}.grid-q-btn:hover{border-color:var(--primary);color:var(--text-main)}.grid-q-btn.answered{background-color:var(--primary);color:#fff;border-color:var(--primary)}.grid-q-btn.flagged{border-color:var(--accent-amber);color:var(--accent-amber);box-shadow:0 0 0 1px var(--accent-amber)}.grid-q-btn.current{border:2px solid var(--text-main);color:var(--text-main)}.scorecard-header{text-align:center;background-color:var(--bg-card);border-radius:var(--radius-lg);border:1px solid var(--border-color);box-shadow:var(--shadow);margin-bottom:32px;padding:40px 20px}.scaled-score-value{letter-spacing:-.03em;margin:12px 0 6px;font-size:4rem;font-weight:900}.pass-badge{text-transform:uppercase;letter-spacing:.05em;border-radius:999px;padding:6px 18px;font-size:1rem;font-weight:800;display:inline-block}.badge-passed{background-color:var(--accent-green-bg);color:var(--accent-green);border:1px solid var(--accent-green)}.badge-failed{background-color:var(--accent-red-bg);color:var(--primary);border:1px solid var(--primary)}.domain-breakdown-list{flex-direction:column;gap:16px;margin-bottom:32px;display:flex}.domain-bar-row{flex-direction:column;gap:6px;display:flex}.progress-track{background-color:var(--border-color);border-radius:999px;width:100%;height:8px;overflow:hidden}.progress-fill{background:var(--primary);border-radius:999px;height:100%}.pbq-interface{background-color:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);box-shadow:var(--shadow);margin-bottom:24px;padding:24px}.cli-terminal{border-radius:var(--radius-md);font-family:var(--font-mono);color:#fff;background-color:#06070a;border:1px solid #282d38;min-height:280px;max-height:380px;margin-bottom:20px;padding:16px;font-size:.9rem;overflow-y:auto}.cli-line{white-space:pre-wrap;word-break:break-all;margin-bottom:4px}.cli-input-row{align-items:center;gap:8px;display:flex}.cli-prompt{color:var(--primary);font-weight:700}.cli-input{color:#fff;font-family:var(--font-mono);background:0 0;border:none;outline:none;flex:1;font-size:.9rem}.acl-table{border-collapse:collapse;width:100%;margin-bottom:20px;font-size:.88rem}.acl-table th,.acl-table td{border:1px solid var(--border-color);text-align:left;padding:8px 10px}.acl-table th{background-color:var(--bg-card-hover);color:var(--text-muted);font-weight:700}.acl-select,.acl-input{background-color:var(--bg-card);border:1px solid var(--border-color);width:100%;color:var(--text-main);border-radius:var(--radius-sm);padding:6px 8px;font-size:.85rem}.drag-bank{background-color:var(--bg-card-hover);border-radius:var(--radius-md);border:1px dashed var(--border-color);flex-wrap:wrap;gap:10px;margin-bottom:24px;padding:16px;display:flex}.drag-item{background-color:var(--bg-card);border:1px solid var(--primary);color:var(--text-main);border-radius:var(--radius-sm);cursor:grab;-webkit-user-select:none;user-select:none;box-shadow:var(--shadow);padding:8px 14px;font-size:.85rem;font-weight:600}.drop-slot{background-color:var(--bg-card-hover);border:2px dashed var(--border-color);border-radius:var(--radius-md);justify-content:space-between;align-items:center;min-height:54px;margin-bottom:10px;padding:12px 16px;display:flex}.drop-slot.filled{border-style:solid;border-color:var(--accent-green);background-color:var(--accent-green-bg)}.pricing-grid{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:20px;margin-bottom:24px;display:grid}.pricing-card{background-color:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);box-shadow:var(--shadow);flex-direction:column;padding:24px;transition:transform .2s,border-color .2s,box-shadow .2s;display:flex;position:relative}.pricing-card:hover{box-shadow:var(--shadow-hover);border-color:#da291c66;transform:translateY(-4px)}.pricing-card.featured{border:2px solid var(--primary);background:linear-gradient(180deg, #da291c0d, var(--bg-card));box-shadow:0 4px 24px #da291c26}.popular-badge{background:var(--primary);color:#fff;text-transform:uppercase;border-radius:999px;padding:3px 10px;font-size:.72rem;font-weight:800;position:absolute;top:-12px;right:20px;box-shadow:0 2px 8px #da291c59}.price-val{color:var(--text-main);margin:12px 0 6px;font-size:2.2rem;font-weight:900}.price-sub{color:var(--text-muted);margin-bottom:20px;font-size:.85rem}.feature-list{flex-direction:column;flex:1;gap:10px;margin-bottom:24px;list-style:none;display:flex}.feature-item{color:var(--text-muted);align-items:center;gap:8px;font-size:.85rem;display:flex}.feature-item.check{color:var(--text-main)}.user-topbar-pill{background-color:var(--bg-card);border:1px solid var(--border-color);cursor:pointer;-webkit-user-select:none;user-select:none;border-radius:999px;align-items:center;gap:10px;padding:4px 10px 4px 5px;transition:all .2s;display:flex}.user-topbar-pill:hover{background-color:var(--bg-card-hover);border-color:var(--primary)}.user-avatar-circle{background:var(--primary);color:#fff;border-radius:999px;flex-shrink:0;justify-content:center;align-items:center;width:30px;height:30px;font-size:.8rem;font-weight:800;display:flex}.user-meta-name{color:var(--text-main);white-space:nowrap;font-size:.85rem;font-weight:700}.user-demo-tag{text-transform:uppercase;border-radius:999px;padding:2px 7px;font-size:.7rem;font-weight:700}.user-demo-tag.available{color:var(--primary);background:#da291c1a;border:1px solid #da291c4d}.user-demo-tag.completed{color:var(--accent-green);background:#10b98126;border:1px solid #10b98159}.demo-stepper{background-color:var(--bg-card);border-radius:var(--radius-md);border:1px solid var(--border-color);box-shadow:var(--shadow);align-items:center;gap:16px;margin-bottom:24px;padding:14px 20px;display:flex}.demo-step-item{color:var(--text-dim);align-items:center;gap:10px;font-size:.9rem;font-weight:700;display:flex}.demo-step-item.active{color:var(--text-main)}.demo-step-item.done{color:var(--accent-green)}.demo-step-num{background:var(--bg-card);border:1px solid var(--border-color);width:26px;height:26px;color:var(--text-muted);border-radius:999px;justify-content:center;align-items:center;font-size:.78rem;display:flex}.demo-step-item.active .demo-step-num{background:var(--primary);color:#fff;border-color:var(--primary)}.demo-step-item.done .demo-step-num{background:var(--accent-green);color:#fff;border-color:var(--accent-green)}.demo-step-divider{background:var(--border-color);flex:1;height:2px}.demo-hero-banner{background:linear-gradient(135deg, #da291c1a, var(--bg-card));border-radius:var(--radius-lg);box-shadow:var(--shadow);border:1px solid #da291c59;margin-bottom:28px;padding:30px;position:relative;overflow:hidden}.demo-opt-item{background-color:var(--bg-card);border:1.5px solid var(--border-color);border-radius:var(--radius-md);cursor:pointer;box-shadow:var(--shadow);align-items:flex-start;gap:14px;margin-bottom:10px;padding:14px 18px;transition:all .2s;display:flex;position:relative}.demo-opt-item:hover{background-color:var(--bg-card-hover);border-color:#da291c73}.demo-opt-item.selected{border-color:var(--primary);background-color:#da291c0f}.demo-opt-item.checked-correct{border-color:var(--accent-green)!important;background-color:#10b9811f!important}.demo-opt-item.checked-wrong{border-color:var(--primary)!important;background-color:#da291c1f!important}.demo-opt-item.checked-true-answer{box-shadow:0 0 0 2px #10b9814d;border-color:var(--accent-green)!important}.demo-explanation-box{background:var(--bg-card);border:1px solid var(--border-color);border-left:4px solid var(--primary);border-radius:var(--radius-md);box-shadow:var(--shadow);margin-top:20px;padding:18px;animation:.3s fadeIn}.demo-explanation-box.correct{border-left-color:var(--accent-green)}.demo-explanation-box.incorrect{border-left-color:var(--primary)}@keyframes fadeIn{0%{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}@media (width<=900px){#sidebar{width:70px}.brand-title span,.nav-item span,.nav-header,.sidebar-footer{display:none}.brand-title{justify-content:center}.nav-item{justify-content:center;padding:12px 0}.page-view{padding:20px}}