@import "https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500&family=JetBrains+Mono:wght@400;500;600;700&family=Source+Sans+Pro:wght@400;600;700&display=swap";:root{--bg-primary:#0d1117;--bg-secondary:#161b22;--bg-card:#21262d;--accent-primary:#58a6ff;--accent-secondary:#238636;--accent-warning:#d29922;--accent-error:#f85149;--text-primary:#e6edf3;--text-secondary:#8b949e;--border:#30363d;--font-heading:"JetBrains Mono", monospace;--font-body:"Source Sans Pro", sans-serif;--font-code:"Fira Code", monospace}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font-body);background:var(--bg-primary);color:var(--text-primary);min-height:100vh;line-height:1.6}h1,h2,h3,h4,h5,h6{font-family:var(--font-heading);font-weight:600;line-height:1.3}code,pre{font-family:var(--font-code)}.app-container{flex-direction:column;min-height:100vh;display:flex}.navbar{background:var(--bg-secondary);border-bottom:1px solid var(--border);z-index:1000;justify-content:space-between;align-items:center;height:60px;padding:0 24px;display:flex;position:fixed;top:0;left:0;right:0}.navbar-brand{font-family:var(--font-heading);color:var(--text-primary);align-items:center;gap:12px;font-size:1.25rem;font-weight:700;text-decoration:none;display:flex}.navbar-brand svg{width:32px;height:32px;color:var(--accent-primary)}.navbar-links{gap:8px;display:flex}.nav-link{color:var(--text-secondary);border-radius:6px;padding:8px 16px;font-weight:500;text-decoration:none;transition:all .2s}.nav-link:hover{color:var(--text-primary);background:var(--bg-card)}.nav-link.active{color:var(--accent-primary);background:#58a6ff1a}.navbar-user{align-items:center;gap:12px;display:flex}.user-avatar{background:var(--accent-primary);border-radius:50%;justify-content:center;align-items:center;width:36px;height:36px;font-size:.9rem;font-weight:600;display:flex}.user-name{font-weight:500}.main-layout{min-height:calc(100vh - 60px);margin-top:60px;display:flex}.sidebar{background:var(--bg-secondary);border-right:1px solid var(--border);width:260px;padding:24px 0;position:fixed;top:60px;bottom:0;left:0;overflow-y:auto}.sidebar-section{margin-bottom:24px}.sidebar-title{text-transform:uppercase;letter-spacing:.05em;color:var(--text-secondary);margin-bottom:12px;padding:0 20px;font-size:.75rem;font-weight:600}.sidebar-item{color:var(--text-secondary);cursor:pointer;align-items:center;gap:12px;padding:10px 20px;text-decoration:none;transition:all .2s;display:flex}.sidebar-item:hover{background:var(--bg-card);color:var(--text-primary)}.sidebar-item.active{color:var(--accent-primary);border-right:3px solid var(--accent-primary);background:#58a6ff1a}.sidebar-item .check{border:2px solid var(--border);border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:18px;height:18px;font-size:.7rem;display:flex}.sidebar-item.completed .check{background:var(--accent-secondary);border-color:var(--accent-secondary);color:#fff}.sidebar-item-title{flex:1;font-size:.9rem}.content-area{flex:1;gap:24px;margin-left:260px;padding:32px;display:flex}.lesson-content{flex:1;max-width:60%}.lesson-header{margin-bottom:24px}.lesson-title{margin-bottom:8px;font-size:2rem}.lesson-meta{color:var(--text-secondary);gap:16px;font-size:.9rem;display:flex}.difficulty{gap:2px;display:flex}.star{color:var(--accent-warning)}.star.empty{opacity:.3}.markdown-content{background:var(--bg-secondary);border-radius:12px;padding:24px;line-height:1.8}.markdown-content h1{border-bottom:1px solid var(--border);margin-bottom:16px;padding-bottom:12px;font-size:1.75rem}.markdown-content h2{margin:24px 0 12px;font-size:1.4rem}.markdown-content p{margin-bottom:16px}.markdown-content code{background:var(--bg-card);border-radius:4px;padding:2px 8px;font-size:.9em}.markdown-content pre{background:var(--bg-primary);border:1px solid var(--border);border-radius:8px;margin:16px 0;padding:16px;overflow-x:auto}.markdown-content pre code{background:0 0;padding:0}.editor-section{flex-direction:column;flex:1;gap:16px;display:flex}.exercise-card{background:var(--bg-secondary);border:1px solid var(--border);border-radius:12px;padding:20px}.exercise-title{color:var(--accent-primary);margin-bottom:8px;font-size:1.1rem}.exercise-description{color:var(--text-secondary);margin-bottom:16px;font-size:.95rem}.editor-wrapper{border:1px solid var(--border);border-radius:8px;overflow:hidden}.editor-actions{gap:8px;margin-top:12px;display:flex}.btn{cursor:pointer;border:none;border-radius:6px;padding:10px 20px;font-size:.9rem;font-weight:600;transition:all .2s}.btn-primary{background:var(--accent-primary);color:#fff}.btn-primary:hover{filter:brightness(1.1);transform:translateY(-2px);box-shadow:0 4px 12px #58a6ff4d}.btn-secondary{background:var(--bg-card);color:var(--text-primary);border:1px solid var(--border)}.btn-secondary:hover{background:var(--border)}.btn-success{background:var(--accent-secondary);color:#fff}.console-output{background:var(--bg-primary);border:1px solid var(--border);max-height:200px;font-family:var(--font-code);border-radius:8px;padding:16px;font-size:.85rem;overflow-y:auto}.console-output .log{border-bottom:1px solid var(--border);color:var(--text-primary);padding:4px 0}.console-output .error{color:var(--accent-error)}.console-output .success{color:var(--accent-secondary)}.modal-overlay{z-index:2000;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);background:#000c;justify-content:center;align-items:center;display:flex;position:fixed;inset:0}.modal{background:var(--bg-secondary);border:1px solid var(--border);border-radius:16px;width:100%;max-width:420px;padding:32px;box-shadow:0 24px 48px #0006}.modal-header{text-align:center;margin-bottom:24px}.modal-title{margin-bottom:8px;font-size:1.5rem}.modal-tabs{background:var(--bg-card);border-radius:8px;gap:4px;margin-bottom:24px;padding:4px;display:flex}.modal-tab{color:var(--text-secondary);cursor:pointer;background:0 0;border:none;border-radius:6px;flex:1;padding:10px;font-weight:600;transition:all .2s}.modal-tab.active{background:var(--accent-primary);color:#fff}.form-group{margin-bottom:16px}.form-label{color:var(--text-secondary);margin-bottom:6px;font-size:.9rem;font-weight:500;display:block}.form-input{background:var(--bg-primary);border:1px solid var(--border);width:100%;color:var(--text-primary);border-radius:8px;padding:12px 16px;font-size:1rem;transition:border-color .2s}.form-input:focus{border-color:var(--accent-primary);outline:none}.form-error{color:var(--accent-error);margin-top:6px;font-size:.85rem}.modal-actions{margin-top:24px}.modal-actions .btn{width:100%}.progress-bar{background:var(--bg-card);border-radius:2px;height:4px;margin-top:8px;overflow:hidden}.progress-fill{background:linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));border-radius:2px;height:100%;transition:width .3s}.home-container{flex:1;max-width:1200px;margin:0 auto;padding:48px}.hero{text-align:center;padding:64px 0}.hero-title{background:linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text;margin-bottom:16px;font-size:3rem}.hero-subtitle{color:var(--text-secondary);margin-bottom:32px;font-size:1.25rem}.hero-cta{justify-content:center;gap:16px;display:flex}.features-grid{grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:24px;margin-top:48px;display:grid}.feature-card{background:var(--bg-secondary);border:1px solid var(--border);border-radius:12px;padding:24px;transition:transform .2s}.feature-card:hover{border-color:var(--accent-primary);transform:translateY(-4px)}.feature-icon{background:#58a6ff1a;border-radius:12px;justify-content:center;align-items:center;width:48px;height:48px;margin-bottom:16px;font-size:1.5rem;display:flex}.feature-title{margin-bottom:8px;font-size:1.25rem}.feature-description{color:var(--text-secondary)}.project-requirements{background:var(--bg-card);border-radius:12px;margin-top:24px;padding:24px}.requirements-list{margin-top:16px;list-style:none}.requirements-list li{border-bottom:1px solid var(--border);align-items:center;gap:12px;padding:12px;display:flex}.requirements-list li:last-child{border-bottom:none}.requirement-check{border:2px solid var(--border);border-radius:50%;justify-content:center;align-items:center;width:20px;height:20px;display:flex}@media (width<=1024px){.sidebar{display:none}.content-area{flex-direction:column;margin-left:0}.lesson-content{max-width:100%}}@media (width<=768px){.navbar-links{display:none}.hero-title{font-size:2rem}.content-area{padding:16px}}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.fade-in{animation:.3s forwards fadeIn}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--bg-primary)}::-webkit-scrollbar-thumb{background:var(--border);border-radius:4px}::-webkit-scrollbar-thumb:hover{background:var(--text-secondary)}