:root{color-scheme:light;--primary:#2563eb;--primary-dark:#1e40af;--primary-light:#3b82f6;--secondary:#0891b2;--accent:#059669;--success:#059669;--warning:#d97706;--danger:#dc2626;--gray-50:#f8fafc;--gray-100:#f1f5f9;--gray-200:#e2e8f0;--gray-300:#cbd5e1;--gray-400:#94a3b8;--gray-500:#64748b;--gray-600:#475569;--gray-700:#334155;--gray-800:#1e293b;--gray-900:#0f172a;--spacing-xs:0.25rem;--spacing-sm:0.5rem;--spacing-md:1rem;--spacing-lg:1.5rem;--spacing-xl:2rem;--spacing-2xl:3rem;--radius-sm:0.375rem;--radius-md:0.5rem;--radius-lg:0.75rem;--radius-xl:1rem;--radius-2xl:1.5rem;--radius-full:9999px;--shadow-sm:0 1px 2px 0 rgba(0,0,0,.05);--shadow-md:0 4px 6px -1px rgba(0,0,0,.1),0 2px 4px -2px rgba(0,0,0,.1);--shadow-lg:0 10px 15px -3px rgba(0,0,0,.1),0 4px 6px -4px rgba(0,0,0,.1);--shadow-xl:0 20px 25px -5px rgba(0,0,0,.1),0 8px 10px -6px rgba(0,0,0,.1);--transition-fast:150ms cubic-bezier(0.4,0,0.2,1);--transition-base:200ms cubic-bezier(0.4,0,0.2,1);--transition-slow:300ms 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var(--transition-base)}.course-content{padding:var(--spacing-xl)}.course-content h4{font-size:1.125rem;margin-bottom:var(--spacing-md);color:var(--gray-900);font-weight:600;line-height:1.5;min-height:3.375em}.course-content h4,.course-content p{display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.course-content p{color:var(--gray-600);margin-bottom:var(--spacing-lg);line-height:1.6;font-size:.95rem}.course-meta{justify-content:space-between;padding-top:var(--spacing-md);border-top:1px solid var(--gray-100)}.course-meta,.duration{display:flex;align-items:center}.duration{color:var(--gray-600);font-size:.9rem;font-weight:500;gap:var(--spacing-xs)}.duration:before{content:"⏱️";font-size:1rem}.price{background:var(--gray-900);color:#fff;padding:6px 14px;border-radius:var(--radius-md);font-weight:700;font-size:1rem}.course-category-tag,.price{transition:all 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p{font-size:.9375rem}.courses-section h2{font-size:2rem}.category-card{padding:24px}.course-content{padding:20px}.filter-tab{min-width:100px;font-size:.75rem;padding:7px 10px}.cta-button{padding:12px 28px;font-size:.9375rem}}.breadcrumb-nav{background:#f8f9fa;padding:15px 0;margin-top:70px;border-bottom:1px solid #e1e5e9}.breadcrumb{list-style:none;gap:10px;flex-wrap:wrap}.breadcrumb,.breadcrumb li{display:flex;align-items:center}.breadcrumb li:not(:last-child):after{content:"›";margin-left:10px;color:#666;font-size:1.2rem}.breadcrumb a{color:#3498db;text-decoration:none;transition:color .3s}.breadcrumb a:hover{color:#2980b9;text-decoration:underline}.breadcrumb li:last-child{color:#666}.course-detail-page{min-height:100vh}.course-hero{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:60px 0}.course-hero-content{max-width:900px}.course-badge{display:inline-block;background:hsla(0,0%,100%,.2);color:#fff;padding:8px 20px;border-radius:25px;font-size:.9rem;font-weight:700;margin-bottom:20px}.course-hero h1{font-size:2.5rem;margin-bottom:20px;line-height:1.2}.course-subtitle{font-size:1.2rem;margin-bottom:30px;opacity:.9}.course-meta-info{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));grid-gap:20px;gap:20px;margin-bottom:30px}.meta-item{display:flex;flex-direction:column;gap:5px}.meta-label{font-size:.85rem;opacity:.8;text-transform:uppercase;letter-spacing:.5px}.meta-value{font-size:1.1rem;font-weight:700}.meta-value a{color:#fff;text-decoration:underline}.meta-value a:hover{opacity:.8}.price-highlight{font-size:1.5rem;color:#f1c40f}.course-actions{display:flex;gap:15px;flex-wrap:wrap}.btn-primary,.btn-secondary{padding:15px 30px;border:none;border-radius:5px;font-size:1rem;font-weight:700;cursor:pointer;transition:all 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li:before{content:"✓";position:absolute;left:0;color:#27ae60;font-weight:700;font-size:1.2rem}.features-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));grid-gap:20px;gap:20px;margin-top:20px}.feature-item{padding:20px;background:#f8f9fa;border-radius:8px;border-left:4px solid #3498db}.feature-item h3{font-size:1.1rem;margin-bottom:10px;color:#2c3e50}.feature-item p{font-size:.9rem;color:#666;margin:0}.course-sidebar{position:relative}.sidebar-card{background:#fff;padding:30px;border-radius:10px;box-shadow:0 5px 15px rgba(0,0,0,.1);position:-webkit-sticky;position:sticky;top:90px}.sidebar-card h3{font-size:1.3rem;margin-bottom:20px;color:#2c3e50}.course-info-list{list-style:none;padding:0;margin-bottom:25px}.course-info-list li{padding:12px 0;border-bottom:1px solid #e1e5e9;color:#555}.course-info-list li:last-child{border-bottom:none}.course-info-list strong{color:#2c3e50;margin-right:8px}.course-info-list a{color:#3498db;text-decoration:none}.course-info-list a:hover{text-decoration:underline}.sidebar-price{display:flex;flex-direction:column;align-items:center;padding:20px 0;margin-bottom:20px;border-top:2px solid #e1e5e9;border-bottom:2px solid #e1e5e9}.price-label{font-size:.9rem;color:#666;text-transform:uppercase;letter-spacing:.5px;margin-bottom:5px}.price-amount{font-size:2.5rem;font-weight:700;color:#27ae60}.related-courses-section{padding:60px 0;background:#f8f9fa}.related-courses-section h2{font-size:2rem;margin-bottom:40px;color:#2c3e50}.category-page{min-height:100vh}.category-hero{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:60px 0;text-align:center}.category-hero h1{font-size:2.5rem;margin-bottom:20px}.category-description{font-size:1.2rem;max-width:800px;margin:0 auto 40px;opacity:.9}.category-stats{display:flex;justify-content:center;gap:40px;flex-wrap:wrap}.stat-item{display:flex;flex-direction:column;align-items:center;gap:5px}.stat-number{font-size:2.5rem;font-weight:700}.stat-label{font-size:.9rem;opacity:.8;text-transform:uppercase;letter-spacing:.5px}.category-cta{background:#2c3e50;color:#fff;padding:60px 0;text-align:center}.cta-content h2{font-size:2rem;margin-bottom:15px}.cta-content p{font-size:1.1rem;margin-bottom:30px;opacity:.9}@media (max-width:768px){.course-content-grid{grid-template-columns:1fr}.sidebar-card{position:static}.category-hero h1,.course-hero h1{font-size:2rem}.course-meta-info{grid-template-columns:repeat(2,1fr)}.course-actions{flex-direction:column}.btn-primary,.btn-secondary{width:100%}.features-grid{grid-template-columns:1fr}}.scroll-progress{position:fixed;top:70px;left:0;height:3px;background:linear-gradient(90deg,var(--primary),var(--secondary));z-index:999;transition:width var(--transition-base);box-shadow:0 0 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var(--gray-200)}.no-courses:before{content:"🔍";display:block;font-size:3rem;margin-bottom:var(--spacing-md);opacity:.5}.scroll-top{position:fixed;bottom:var(--spacing-xl);right:var(--spacing-xl);width:50px;height:50px;background:linear-gradient(135deg,var(--primary),var(--secondary));color:#fff;border:none;border-radius:var(--radius-full);cursor:pointer;display:flex;align-items:center;justify-content:center;font-size:1.5rem;box-shadow:var(--shadow-lg);transition:all var(--transition-base);opacity:0;visibility:hidden;z-index:999}.scroll-top.visible{opacity:1;visibility:visible}.scroll-top:hover{transform:translateY(-4px);box-shadow:var(--shadow-xl)}.scroll-top:active{transform:translateY(-2px)}@media (max-width:768px){.hero-content h2{font-size:2.5rem}.courses-section h2{font-size:2rem}.category-card h3{font-size:1.2rem}.search-container:before{transform:translate(calc(-50% + 10px),-50%)}.search-input{padding-left:2.5rem}}@media (max-width:480px){.hero-content h2{font-size:2rem}.courses-section h2{font-size:1.75rem}.cta-button{padding:14px 30px;font-size:1rem}.category-icon{font-size:2.5rem}.filter-tabs{padding:var(--spacing-sm)}.filter-tab{font-size:.85rem;padding:var(--spacing-sm) var(--spacing-md)}}.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border-width:0}a,button{-webkit-tap-highlight-color:transparent}.category-card,.filter-tab,button{user-select:none;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none}a,button,input,select,textarea{transition:all var(--transition-base)}