.xp-system{background:var(--color-card);border-radius:var(--border-radius-large);padding:var(--spacing-lg);box-shadow:var(--shadow-medium);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.1);margin-bottom:var(--spacing-lg);width:100%;position:relative;overflow:hidden}.xp-level{margin-bottom:var(--spacing-md)}.level-badge,.xp-level{display:flex;align-items:center}.level-badge{width:50px;height:50px;border-radius:var(--border-radius-circle);background:var(--gradient-accent);justify-content:center;margin-right:var(--spacing-md);box-shadow:var(--shadow-small),0 0 10px rgba(179,136,255,.5);transition:transform .3s ease,box-shadow .3s ease}.level-badge.level-up{transform:scale(1.2);box-shadow:var(--shadow-medium),0 0 20px rgba(179,136,255,.8);animation:pulse 1.5s infinite}@keyframes pulse{0%{box-shadow:var(--shadow-small),0 0 10px rgba(179,136,255,.5)}50%{box-shadow:var(--shadow-medium),0 0 20px rgba(179,136,255,.8)}to{box-shadow:var(--shadow-small),0 0 10px rgba(179,136,255,.5)}}.level-number{font-family:var(--font-heading);font-size:var(--font-size-lg);font-weight:700;color:var(--color-text-primary)}.level-info{flex:1}.level-info h3{font-family:var(--font-heading);font-size:var(--font-size-md);color:var(--color-text-primary)}.level-info h3,.user-rank{margin-bottom:var(--spacing-xs)}.user-rank{font-size:var(--font-size-sm);color:var(--color-accent);font-weight:600}.level-info p{margin:0;font-size:.9rem;color:rgba(255,255,255,.7)}.xp-remaining{font-size:.8rem;color:rgba(255,255,255,.6);font-style:italic;margin:.25rem 0 0;display:flex;align-items:center;flex-wrap:wrap;gap:.5rem}.xp-multiplier{color:#4CAF50;font-weight:600;background:rgba(76,175,80,.1);padding:2px 6px;border-radius:4px;font-style:normal;animation:glow 1.5s infinite alternate;white-space:nowrap}.xp-progress-container{width:100%}.xp-progress-bar{height:10px;background:rgba(255,255,255,.1)}.xp-progress,.xp-progress-bar{border-radius:var(--border-radius-small);overflow:hidden;position:relative}.xp-progress{height:100%;background:var(--gradient-accent);transition:width .5s ease-out}.xp-progress.level-up-progress{animation:progressPulse 1.5s infinite}@keyframes progressPulse{0%{opacity:.7}50%{opacity:1}to{opacity:.7}}.xp-progress:after{content:"";position:absolute;top:0;left:0;right:0;bottom:0;background:linear-gradient(90deg,rgba(255,255,255,0),rgba(255,255,255,.2) 50%,rgba(255,255,255,0));animation:shimmer 2s infinite}@keyframes shimmer{0%{transform:translateX(-100%)}to{transform:translateX(100%)}}.level-up-animation{position:absolute;top:0;left:0;right:0;bottom:0;background:rgba(0,0,0,.7);display:flex;flex-direction:column;align-items:center;justify-content:center;z-index:10;animation:fadeIn .3s ease-in;border-radius:var(--border-radius-large)}.level-up-text{font-family:var(--font-heading);font-size:var(--font-size-xl);font-weight:700;color:var(--color-accent);margin-bottom:var(--spacing-md);text-shadow:0 0 10px rgba(179,136,255,.8);animation:scaleIn .5s ease-out}.level-up-details{font-size:var(--font-size-md);color:var(--color-text-primary);animation:slideUp .5s ease-out .2s both}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes scaleIn{0%{transform:scale(.5);opacity:0}to{transform:scale(1);opacity:1}}@keyframes slideUp{0%{transform:translateY(20px);opacity:0}to{transform:translateY(0);opacity:1}}@media (max-width:768px){.xp-system{padding:var(--spacing-md)}.level-badge{width:40px;height:40px}.level-number{font-size:var(--font-size-md)}}.topic-page{max-width:1200px;margin:0 auto;padding:var(--spacing-xl);color:var(--color-text-primary);position:relative;overflow:hidden}.topic-page:before{content:"";position:absolute;top:0;left:0;right:0;bottom:0;background-image:radial-gradient(1px 1px at 25% 30%,rgba(255,255,255,.6) 0,rgba(255,255,255,0) 100%),radial-gradient(1px 1px at 50% 50%,rgba(255,255,255,.4) 0,rgba(255,255,255,0) 100%),radial-gradient(1px 1px at 75% 10%,rgba(255,255,255,.5) 0,rgba(255,255,255,0) 100%),radial-gradient(2px 2px at 10% 80%,rgba(255,255,255,.3) 0,rgba(255,255,255,0) 100%),radial-gradient(2px 2px at 90% 70%,rgba(255,255,255,.5) 0,rgba(255,255,255,0) 100%);opacity:.15;z-index:-1;pointer-events:none}.topic-header{margin-top:100px;display:flex;justify-content:space-between;align-items:center;margin-bottom:var(--spacing-xl);flex-wrap:wrap;gap:var(--spacing-lg);position:relative}.topic-header h1{font-family:var(--font-heading);font-size:var(--font-size-xxl);background:linear-gradient(90deg,var(--color-accent-light),var(--color-secondary-light));-webkit-background-clip:text;-webkit-text-fill-color:transparent;margin:0;text-shadow:0 0 15px rgba(179,136,255,.3);position:relative}.topic-header h1:after{content:"";position:absolute;bottom:-8px;left:0;width:60%;height:2px;background:var(--gradient-accent);border-radius:var(--border-radius-small)}.completion-badge{display:flex;align-items:center;gap:var(--spacing-xs);background:var(--gradient-accent);padding:var(--spacing-xs) var(--spacing-md);border-radius:var(--border-radius-large);margin-bottom:var(--spacing-lg);width:fit-content;box-shadow:var(--shadow-medium),0 0 15px rgba(98,0,234,.5);animation:pulse 3s infinite alternate}.completion-icon{font-size:var(--font-size-lg)}.completion-text{font-weight:600}.topic-progress-container{margin-bottom:var(--spacing-lg);background:var(--color-card);border-radius:var(--border-radius-large);padding:var(--spacing-md);box-shadow:var(--shadow-small);border:1px solid rgba(255,255,255,.1);backdrop-filter:blur(5px)}.topic-progress-label{display:flex;justify-content:space-between;margin-bottom:var(--spacing-xs);font-size:var(--font-size-sm);color:var(--color-text-secondary)}.topic-progress-bar{height:10px;background:rgba(255,255,255,.1);border-radius:var(--border-radius-small);overflow:hidden}.topic-progress-fill{height:100%;background:var(--gradient-accent);border-radius:var(--border-radius-small);transition:width .5s ease-out;box-shadow:0 0 10px rgba(98,0,234,.5)}.level-up-notification{position:fixed;top:20px;right:20px;background:var(--color-card);border-radius:var(--border-radius-large);padding:var(--spacing-md);box-shadow:var(--shadow-large);border:2px solid var(--color-accent);z-index:1000;animation:slideIn .5s ease-out,glow 2s infinite alternate;max-width:300px;backdrop-filter:blur(10px)}.level-up-content{text-align:center}.level-up-content h3{font-family:var(--font-heading);font-size:var(--font-size-lg);color:var(--color-accent-light);margin-bottom:var(--spacing-xs);text-shadow:0 0 10px rgba(179,136,255,.5)}.level-up-content p{margin:var(--spacing-xs) 0}@keyframes slideIn{0%{transform:translateX(100%);opacity:0}to{transform:translateX(0);opacity:1}}@keyframes glow{0%{box-shadow:0 0 10px var(--color-accent)}to{box-shadow:0 0 20px var(--color-accent)}}.topic-content{background:var(--color-card);border-radius:var(--border-radius-large);padding:var(--spacing-xl);box-shadow:var(--shadow-medium);border:1px solid rgba(255,255,255,.1);backdrop-filter:blur(10px);position:relative;overflow:hidden}.topic-content:before{content:"";position:absolute;top:0;right:0;width:100px;height:100px;background:radial-gradient(circle,rgba(179,136,255,.2) 0,rgba(179,136,255,0) 70%);border-radius:50%;z-index:-1}.content-section{margin-bottom:var(--spacing-xxl);position:relative}.content-section h2{font-family:var(--font-heading);font-size:var(--font-size-xl);margin-bottom:var(--spacing-lg);color:var(--color-accent-light);border-bottom:1px solid rgba(255,255,255,.1);padding-bottom:var(--spacing-sm);text-shadow:0 0 10px rgba(179,136,255,.3);display:inline-block}.content-section h2:before{content:"✧";margin-right:var(--spacing-sm);color:var(--color-accent);opacity:.7}.objectives-list{list-style-type:none;padding:0}.objectives-list li{position:relative;padding-left:var(--spacing-xl);margin-bottom:var(--spacing-md);line-height:1.6}.objectives-list li:before{content:"🚀";position:absolute;left:0;top:0}.concept-section{margin-bottom:var(--spacing-xl);background:rgba(255,255,255,.05);border-radius:var(--border-radius-medium);padding:var(--spacing-lg);border:1px solid rgba(255,255,255,.1);transition:transform var(--transition-medium),box-shadow var(--transition-medium);position:relative;overflow:hidden}.concept-section:hover{transform:translateY(-3px);box-shadow:var(--shadow-medium),0 0 15px rgba(98,0,234,.2)}.concept-section:after{content:"";position:absolute;top:0;left:0;width:100%;height:100%;background:linear-gradient(135deg,rgba(255,255,255,.05),rgba(255,255,255,0));pointer-events:none}.concept-section h3{font-size:var(--font-size-lg);margin-bottom:var(--spacing-md);color:var(--color-secondary-light);font-family:var(--font-heading);letter-spacing:.5px}.concept-content p{line-height:1.8;margin-bottom:var(--spacing-md)}.example-box{background:rgba(0,0,0,.2);border-radius:var(--border-radius-medium);padding:var(--spacing-lg);margin:var(--spacing-lg) 0;border-left:4px solid var(--color-accent);box-shadow:var(--shadow-small)}.example-box:before{width:50px;height:50px;background:radial-gradient(circle,rgba(98,0,234,.1) 0,rgba(98,0,234,0) 70%);border-radius:50%;z-index:0}.example-box h4{font-size:var(--font-size-md);margin-bottom:var(--spacing-sm);color:var(--color-accent-light);font-family:var(--font-heading);letter-spacing:.5px}.solution{margin-top:var(--spacing-md);padding-top:var(--spacing-md);border-top:1px dashed rgba(255,255,255,.1);position:relative}.solution h5{font-size:var(--font-size-sm);margin-bottom:var(--spacing-xs);color:var(--color-text-secondary);display:inline-block;background:rgba(0,0,0,.2);padding:2px 8px;border-radius:var(--border-radius-small)}.concept-image{margin:var(--spacing-lg) 0;text-align:center}.concept-image img{max-width:100%;border-radius:var(--border-radius-medium);box-shadow:var(--shadow-medium);border:1px solid rgba(255,255,255,.1)}.quiz-prompt{padding:var(--spacing-lg);background:rgba(255,255,255,.03);border-radius:var(--border-radius-large);margin-bottom:var(--spacing-lg);border:1px solid rgba(255,255,255,.05)}.quiz-options{gap:var(--spacing-xl);margin-top:var(--spacing-lg)}.quiz-btn{background:var(--color-surface);border-radius:var(--border-radius-large);padding:var(--spacing-lg) var(--spacing-xl);color:var(--color-text-primary);font-size:var(--font-size-md);font-weight:600;transition:all var(--transition-medium);box-shadow:var(--shadow-medium);min-width:200px;display:flex;flex-direction:column;align-items:center;gap:var(--spacing-sm);position:relative;overflow:hidden}.quiz-btn:after{content:"";position:absolute;top:-50%;left:-50%;width:200%;height:200%;background:radial-gradient(circle,rgba(255,255,255,.1) 0,rgba(255,255,255,0) 70%);opacity:0;transition:opacity var(--transition-medium);pointer-events:none}.quiz-btn:hover{transform:translateY(-3px);box-shadow:var(--shadow-large)}.quiz-btn:hover:after{opacity:1}.quiz-btn:active{transform:translateY(1px)}.challenge-btn{background:linear-gradient(135deg,#ff5e62,#ff9966)}.casual-btn{background:linear-gradient(135deg,#4facfe,#00f2fe)}.quiz-btn-description{font-size:var(--font-size-sm);display:flex;flex-direction:column;align-items:center;gap:var(--spacing-xs);margin-top:var(--spacing-xs)}.hearts{letter-spacing:2px}.navigation-buttons{display:flex;justify-content:space-between;margin-top:var(--spacing-xxl);flex-wrap:wrap;gap:var(--spacing-md)}.nav-button{background:var(--color-surface);color:var(--color-text-primary);text-decoration:none;padding:var(--spacing-md) var(--spacing-lg);border-radius:var(--border-radius-medium);font-weight:600;box-shadow:var(--shadow-small);border:1px solid rgba(255,255,255,.1);display:inline-block;position:relative;overflow:hidden}.nav-button,.nav-button:after{transition:all var(--transition-medium)}.nav-button:after{content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;background:linear-gradient(90deg,rgba(255,255,255,0),rgba(255,255,255,.1) 50%,rgba(255,255,255,0))}.nav-button:hover{background:var(--color-surface-hover);transform:translateY(-2px);box-shadow:var(--shadow-medium)}.nav-button:hover:after{left:100%}.prev-button:before{content:"←";margin-right:var(--spacing-xs)}.next-button:after{content:"→";margin-left:var(--spacing-xs)}@media (max-width:768px){.topic-header{flex-direction:column;align-items:flex-start}.quiz-options{flex-direction:column;align-items:center}.quiz-btn{width:100%;max-width:300px}.navigation-buttons{flex-direction:column;align-items:center}.nav-button{width:100%;text-align:center}}@media (max-width:480px){.topic-page{padding:var(--spacing-md)}.topic-content{padding:var(--spacing-lg)}.topic-header h1{font-size:var(--font-size-xl)}.content-section h2{font-size:var(--font-size-lg)}}.visual-aid{background:linear-gradient(135deg,#2d1e60,#1a1440);border-radius:12px;padding:20px;margin:20px 0;border:1px solid #7b2ff244;box-shadow:0 4px 16px rgba(123,47,242,.1)}.visual-aid h4{color:#b490ca;margin-bottom:12px;font-size:1.2em}.visual-aid p{color:#b7b7ff;margin-bottom:16px;line-height:1.6}.power-calculator{background:rgba(123,47,242,.1);border-radius:8px;padding:16px;margin-top:12px}.calculator-inputs{display:flex;gap:16px;margin-bottom:16px;flex-wrap:wrap}.calculator-inputs label{display:flex;flex-direction:column;color:#b7b7ff;font-size:.9em}.calculator-inputs input{background:rgba(255,255,255,.1);border:1px solid #7b2ff244;border-radius:6px;padding:8px 12px;color:#fff;font-size:1em;margin-top:4px;width:80px}.calculator-inputs input:focus{outline:none;border-color:#00c6ff;box-shadow:0 0 0 2px rgba(0,198,255,.2)}.calculator-result{display:flex;align-items:center;justify-content:center;gap:12px;margin-bottom:12px;font-size:1.2em}.power-expression{color:#b490ca;font-weight:700;font-size:1.4em}.equals{color:#b7b7ff;font-size:1.2em}.result{font-size:1.4em}.calculation-breakdown{color:#b7b7ff;font-size:.9em;text-align:center;font-style:italic}.diagram-container{display:flex;justify-content:center;margin:16px 0}.diagram-placeholder{background:rgba(255,255,255,.05);border-radius:8px;padding:20px;border:1px solid #7b2ff244}.division-visual{display:flex;flex-direction:column;align-items:center;gap:8px;color:#b7b7ff;font-size:1.2em}.denominator,.numerator{color:#b490ca;font-weight:700}.division-line{color:#7b2ff2;font-size:1.4em}.arrow{color:#00c6ff;font-size:1.2em}.result{color:#00c6ff;font-weight:700}.real-world-example{background:linear-gradient(135deg,#1a1440,#2d1e60);border-radius:12px;padding:20px;margin:20px 0;border-left:4px solid #00c6ff}.real-world-example h4{color:#00c6ff;margin-bottom:12px;font-size:1.1em}.real-world-example p{color:#b7b7ff;margin-bottom:12px;line-height:1.6}.calculation-box{background:rgba(0,198,255,.1);border-radius:6px;padding:12px;color:#b7b7ff;font-family:Courier New,monospace;font-size:.9em}.interactive-example{background:linear-gradient(135deg,#2d1e60,#1a1440);border-radius:12px;padding:20px;margin:20px 0;border-left:4px solid #b490ca}.interactive-example h4{color:#b490ca;margin-bottom:16px;font-size:1.1em}.practice-problems{display:flex;flex-direction:column;gap:12px}.practice-problem{background:rgba(180,144,202,.1);border-radius:8px;padding:12px;border:1px solid #b490ca44}.problem-statement{color:#b7b7ff;font-size:1em;margin-bottom:8px}.problem-answer{color:#00c6ff;font-weight:700;font-size:.9em}.step-by-step{margin-top:16px}.step-toggle-btn{background:linear-gradient(90deg,#7b2ff2,#00c6ff);color:#fff;border:none;border-radius:6px;padding:8px 16px;font-size:.9em;cursor:pointer;transition:all .2s}.step-toggle-btn:hover{transform:translateY(-1px);box-shadow:0 4px 12px rgba(123,47,242,.3)}.steps-list{margin-top:12px;background:rgba(255,255,255,.05);border-radius:8px;padding:16px}.step-item{display:flex;align-items:flex-start;gap:12px;margin-bottom:8px;padding:8px 0;border-bottom:1px solid rgba(255,255,255,.1)}.step-item:last-child{border-bottom:none;margin-bottom:0}.step-number{background:linear-gradient(90deg,#7b2ff2,#00c6ff);color:#fff;border-radius:50%;width:24px;height:24px;display:flex;align-items:center;justify-content:center;font-size:.8em;font-weight:700;flex-shrink:0}.step-text{color:#b7b7ff;line-height:1.5;flex:1}.difficulty-badge{margin-top:16px}.difficulty-basic{background:linear-gradient(90deg,#4caf50,#45a049)}.difficulty-basic,.difficulty-intermediate{color:#fff;padding:4px 12px;border-radius:12px;font-size:.8em;font-weight:700}.difficulty-intermediate{background:linear-gradient(90deg,#ff9800,#f57c00)}.difficulty-advanced{background:linear-gradient(90deg,#f44336,#d32f2f);color:#fff;padding:4px 12px;border-radius:12px;font-size:.8em;font-weight:700}.tips-section{background:rgba(255,193,7,.1);border-radius:8px;padding:16px;margin-top:16px;border-left:4px solid #ffc107}.tips-section h4{color:#ffc107;margin-bottom:12px;font-size:1em}.tips-list{color:#b7b7ff;padding-left:20px}.tips-list li{margin-bottom:6px;line-height:1.5}.mistakes-list{display:flex;flex-direction:column;gap:16px}.mistake-item{background:linear-gradient(135deg,#1a1440,#2d1e60);border-radius:12px;padding:16px;border:1px solid #f4433644}.mistake-header{color:#f44336}.mistake-correction,.mistake-header{display:flex;align-items:center;gap:8px;margin-bottom:8px;font-weight:700}.mistake-correction{color:#4caf50}.mistake-example{color:#b7b7ff;font-size:.9em;font-family:Courier New,monospace;background:rgba(255,255,255,.05);padding:8px;border-radius:4px;margin-top:8px}.resources-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:16px;margin-top:16px}.resource-item{background:linear-gradient(135deg,#2d1e60,#1a1440);border-radius:12px;padding:16px;border:1px solid #7b2ff244;display:flex;align-items:flex-start;gap:12px;transition:transform .2s}.resource-item:hover{transform:translateY(-2px)}.resource-icon{font-size:1.5em;flex-shrink:0}.resource-content h4{color:#b490ca;margin-bottom:8px;font-size:1em}.resource-content p{color:#b7b7ff;font-size:.9em;line-height:1.4;margin-bottom:4px}.duration{color:#7b2ff2;font-size:.8em;font-weight:700}.quiz-prompt{text-align:center;padding:24px;background:linear-gradient(135deg,#2d1e60,#1a1440);border-radius:12px;margin:20px 0}.quiz-prompt p{color:#b7b7ff;font-size:1.1em;margin-bottom:20px}.quiz-options{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}.quiz-btn{background:linear-gradient(135deg,#7b2ff2,#00c6ff);color:#fff;border:none;border-radius:8px;padding:16px 24px;font-size:1em;font-weight:700;cursor:pointer;transition:all .2s;min-width:160px}.quiz-btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(123,47,242,.3)}.challenge-btn{background:linear-gradient(135deg,#f44336,#d32f2f)}.casual-btn{background:linear-gradient(135deg,#4caf50,#45a049)}.quiz-btn-description{font-size:.8em;font-weight:400;margin-top:4px;opacity:.9}@media (max-width:768px){.calculator-inputs{flex-direction:column;gap:12px}.calculator-inputs input{width:100%}.resources-grid{grid-template-columns:1fr}.quiz-options{flex-direction:column;align-items:center}.quiz-btn{width:100%;max-width:280px}.steps-list{padding:12px}.step-item{flex-direction:column;gap:8px}.step-number{align-self:flex-start}}.interactive-example,.mistake-item,.real-world-example,.resource-item,.visual-aid{animation:fadeInUp .6s ease-out}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.example-box{background:linear-gradient(135deg,#1a1440,#2d1e60);border-radius:12px;padding:20px;margin:20px 0;border:1px solid #7b2ff244;position:relative;overflow:hidden}.example-box:before{content:"";position:absolute;top:0;left:0;right:0;height:3px;background:linear-gradient(90deg,#7b2ff2,#00c6ff)}.example-box h4{color:#b490ca;margin-bottom:12px;font-size:1.1em}.example-box p{color:#b7b7ff;margin-bottom:12px;line-height:1.6}.solution{background:rgba(123,47,242,.1);border-radius:8px;padding:16px;margin-top:12px}.solution h5{color:#00c6ff;margin-bottom:8px;font-size:1em}.solution p{color:#b7b7ff;line-height:1.6;margin-bottom:0}