:root{--bg-main:#0b0f19;--bg-panel:#111827;--bg-panel-light:#1f2937;--bg-active:#374151;--text-main:#f3f4f6;--text-muted:#9ca3af;--text-dark:#1f2937;--primary:#6366f1;--primary-hover:#4f46e5;--primary-light:#818cf8;--primary-glow:#6366f126;--success:#10b981;--success-bg:#10b9811a;--success-border:#10b9814d;--warning:#f59e0b;--warning-bg:#f59e0b1a;--warning-border:#f59e0b4d;--error:#ef4444;--error-bg:#ef44441a;--error-border:#ef44444d;--border-color:#1f2937;--border-light:#374151;--sans:"Outfit", "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--mono:"Fira Code", "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--sans);background-color:var(--bg-main);color:var(--text-main);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;min-height:100vh;line-height:1.5;overflow:hidden}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:var(--bg-main)}::-webkit-scrollbar-thumb{background:var(--border-light);border-radius:3px}::-webkit-scrollbar-thumb:hover{background:var(--primary-light)}#root{flex-direction:column;width:100vw;height:100vh;display:flex}.app-container{flex-direction:column;width:100%;height:100vh;display:flex}.app-header{background-color:var(--bg-panel);border-bottom:1px solid var(--border-color);z-index:10;justify-content:space-between;align-items:center;height:60px;padding:0 24px;display:flex;box-shadow:0 4px 20px #00000040}.header-logo{align-items:center;gap:10px;display:flex}.logo-icon{color:var(--primary-light);animation:12s linear infinite spin}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.logo-text{letter-spacing:-.5px;background:linear-gradient(135deg, #fff 30%, var(--primary-light) 100%);-webkit-text-fill-color:transparent;-webkit-background-clip:text;font-size:20px;font-weight:800}.logo-badge{background:var(--primary-glow);color:var(--primary-light);border:1px solid var(--primary-hover);border-radius:9999px;padding:2px 8px;font-size:11px;font-weight:600}.header-progress{align-items:center;gap:16px;display:flex}.progress-label{color:var(--text-muted);font-size:14px}.progress-bar-bg{background-color:var(--bg-panel-light);border:1px solid var(--border-color);border-radius:9999px;width:150px;height:8px;overflow:hidden}.progress-bar-fill{background:linear-gradient(90deg, var(--primary) 0%, var(--primary-light) 100%);height:100%;box-shadow:0 0 10px var(--primary-light);border-radius:9999px;transition:width .4s cubic-bezier(.4,0,.2,1)}.workspace{flex:1;grid-template-columns:1fr 420px;height:calc(100vh - 60px);display:grid;overflow:hidden}@media (width<=1200px){.workspace{grid-template-columns:1fr}}.panel{background-color:var(--bg-panel);border-right:1px solid var(--border-color);flex-direction:column;height:100%;display:flex;overflow:hidden}.panel:last-child{border-right:none}.panel-header{border-bottom:1px solid var(--border-color);background-color:#00000026;justify-content:space-between;align-items:center;height:48px;padding:0 16px;display:flex}.panel-title{text-transform:uppercase;letter-spacing:1px;color:var(--text-muted);align-items:center;gap:8px;font-size:13px;font-weight:700;display:flex}.panel-content{flex:1;padding:20px;overflow-y:auto}.lecture-container{flex-direction:column;gap:20px;display:flex}.lesson-navigation{background:var(--bg-panel-light);border:1px solid var(--border-color);border-radius:8px;justify-content:space-between;align-items:center;padding:8px 12px;display:flex}.nav-btn{color:var(--text-main);cursor:pointer;background:0 0;border:none;border-radius:6px;align-items:center;padding:6px;transition:all .2s;display:flex}.nav-btn:hover:not(:disabled){background-color:var(--bg-active);color:var(--primary-light)}.nav-btn:disabled{opacity:.3;cursor:not-allowed}.lesson-selector-dropdown{background-color:var(--bg-panel);color:var(--text-main);border:1px solid var(--border-light);cursor:pointer;border-radius:6px;outline:none;max-width:180px;padding:6px 12px;font-size:14px;font-weight:600}.lecture-markdown h1{color:#fff;letter-spacing:-.5px;margin-bottom:12px;font-size:22px;font-weight:800}.lecture-markdown h2,.lecture-markdown h3{color:var(--primary-light);margin-top:18px;margin-bottom:8px;font-size:16px;font-weight:700}.lecture-markdown p{color:var(--text-muted);margin-bottom:12px;font-size:14px;line-height:1.6}.lecture-markdown code{font-family:var(--mono);background-color:var(--bg-panel-light);border:1px solid var(--border-color);color:#f43f5e;border-radius:4px;padding:2px 6px;font-size:12px}.lecture-markdown pre{border:1px solid var(--border-color);background-color:#1e1e2e;border-radius:8px;margin:12px 0;padding:12px;overflow-x:auto}.lecture-markdown pre code{color:#cdd6f4;background:0 0;border:none;padding:0;font-size:12px}.task-box{background:linear-gradient(135deg,#6366f114 0%,#818cf805 100%);border:1px solid #6366f140;border-radius:12px;margin-top:10px;padding:16px;box-shadow:inset 0 0 12px #6366f10d}.task-header{color:var(--primary-light);align-items:center;gap:8px;margin-bottom:8px;font-size:14px;font-weight:700;display:flex}.task-body{color:var(--text-main);font-size:13.5px;line-height:1.5}.task-body ul{margin-top:6px;margin-left:20px}.task-body li{margin-bottom:4px}.hints-container{margin-top:8px}.hints-trigger{background-color:var(--bg-panel-light);border:1px solid var(--border-color);width:100%;color:var(--text-muted);cursor:pointer;border-radius:8px;justify-content:space-between;align-items:center;padding:10px 14px;font-size:13px;font-weight:600;transition:all .2s;display:flex}.hints-trigger:hover{background-color:var(--bg-active);color:var(--text-main)}.hints-content{border:1px solid var(--border-color);color:var(--text-muted);background-color:#0000001a;border-top:none;border-radius:0 0 8px 8px;flex-direction:column;gap:10px;padding:14px;font-size:13px;display:flex}.hint-item{gap:8px;display:flex}.hint-number{background-color:var(--primary-glow);color:var(--primary-light);border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:18px;height:18px;font-size:11px;font-weight:700;display:flex}.editor-container{flex-direction:column;height:100%;display:flex}.editor-wrapper{border:1px solid var(--border-color);background-color:#1e1e1e;border-radius:8px;flex:1;overflow:hidden;box-shadow:inset 0 0 20px #00000080}.editor-toolbar{background-color:#1a1a1a;border-bottom:1px solid #2d2d2d;justify-content:space-between;align-items:center;height:42px;padding:0 16px;display:flex}.file-tab{color:#fff;height:42px;font-size:12px;font-family:var(--mono);background-color:#1e1e1e;border-right:1px solid #2d2d2d;align-items:center;gap:8px;padding:0 16px;display:flex}.file-tab-icon{color:#e34c26}.editor-actions{gap:8px;display:flex}.editor-btn{color:#ccc;cursor:pointer;background-color:#2d2d2d;border:1px solid #3d3d3d;border-radius:4px;align-items:center;gap:6px;padding:4px 10px;font-size:12px;font-weight:500;transition:all .2s;display:flex}.editor-btn:hover{color:#fff;background-color:#3d3d3d}.editor-btn.run{background-color:var(--primary);border-color:var(--primary-light);color:#fff}.editor-btn.run:hover{background-color:var(--primary-hover);box-shadow:0 0 8px var(--primary-light)}.preview-panel,.preview-split{flex-direction:column;height:100%;display:flex}.preview-box{background-color:var(--bg-panel-light);border:1px solid var(--border-color);border-radius:8px;flex-direction:column;flex:3;min-height:150px;margin-bottom:16px;display:flex;overflow:hidden}.preview-content{background-image:radial-gradient(#2d3748 1px,#0000 1px);background-size:20px 20px;flex:1;padding:16px;position:relative;overflow:auto}.preview-placeholder{height:100%;color:var(--text-muted);text-align:center;flex-direction:column;justify-content:center;align-items:center;gap:12px;padding:24px;display:flex}.console-box{border:1px solid var(--border-color);min-height:120px;font-family:var(--mono);background-color:#0d0e15;border-radius:8px;flex-direction:column;flex:2;display:flex;overflow:hidden}.console-header{border-bottom:1px solid var(--border-color);background-color:#141520;justify-content:space-between;align-items:center;height:36px;padding:0 12px;display:flex}.console-title{text-transform:uppercase;letter-spacing:.5px;color:var(--text-muted);align-items:center;gap:6px;font-size:11px;font-weight:700;display:flex}.console-clear{color:var(--text-muted);cursor:pointer;background:0 0;border:none;border-radius:4px;align-items:center;padding:2px;display:flex}.console-clear:hover{background-color:var(--bg-active);color:#fff}.console-logs{flex-direction:column;flex:1;gap:6px;padding:12px;font-size:12px;line-height:1.6;display:flex;overflow-y:auto}.console-log-row{border-bottom:1px solid #ffffff08;gap:8px;padding-bottom:4px;display:flex}.console-log-row.error{color:#f87171;background-color:#ef44440d}.console-log-row.warn{color:#fbbf24}.console-log-row.info{color:#60a5fa}.console-log-prefix{color:#4b5563;-webkit-user-select:none;user-select:none}.console-log-text{word-break:break-all;white-space:pre-wrap}.validation-banner{border-radius:12px;flex-direction:column;gap:12px;margin-top:16px;padding:16px;animation:.3s cubic-bezier(.16,1,.3,1) slideUp;display:flex}@keyframes slideUp{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.validation-banner.success{background-color:var(--success-bg);border:1px solid var(--success-border);color:#34d399}.validation-banner.error{background-color:var(--error-bg);border:1px solid var(--error-border);color:#f87171}.validation-title{align-items:center;gap:10px;font-size:15px;font-weight:700;display:flex}.validation-msg{color:var(--text-main);font-size:13px;line-height:1.5}.next-lesson-btn{background-color:var(--success);color:#fff;cursor:pointer;border:none;border-radius:6px;align-self:flex-start;align-items:center;gap:8px;padding:8px 16px;font-size:13px;font-weight:700;transition:all .2s;display:inline-flex;box-shadow:0 4px 12px #10b9814d}.next-lesson-btn:hover{background-color:#059669;transform:translateY(-1px);box-shadow:0 6px 16px #10b98166}.compile-error-box{color:#fca5a5;font-family:var(--mono);background-color:#450a0a;border:1px solid #991b1b;border-radius:8px;height:100%;padding:14px;font-size:12px;overflow:auto}.compile-error-title{color:#ef4444;align-items:center;gap:6px;margin-bottom:8px;font-size:13px;font-weight:700;display:flex}.compile-error-stack{white-space:pre-wrap;line-height:1.5}.lesson-list-container{flex-direction:column;gap:8px;margin-bottom:20px;display:flex}.category-title{color:var(--primary-light);text-transform:uppercase;letter-spacing:1.5px;margin-top:12px;margin-bottom:6px;font-size:11px;font-weight:700}.lesson-list-item{background-color:var(--bg-panel-light);border:1px solid var(--border-color);cursor:pointer;border-radius:8px;justify-content:space-between;align-items:center;padding:10px 14px;transition:all .2s;display:flex}.lesson-list-item:hover{background-color:var(--bg-active);border-color:var(--border-light)}.lesson-list-item.active{background-color:var(--primary-glow);border-color:var(--primary-light)}.lesson-list-item-title{color:var(--text-main);text-overflow:ellipsis;white-space:nowrap;max-width:220px;font-size:13px;font-weight:600;overflow:hidden}.lesson-list-item-title.active{color:#fff;font-weight:700}.lesson-status-icon{justify-content:center;align-items:center;width:18px;height:18px;display:flex}.status-check{color:var(--success)}.status-circle{background-color:var(--border-light);border-radius:50%;width:8px;height:8px}.status-circle.active{background-color:var(--primary-light);box-shadow:0 0 6px var(--primary-light)}.run-floating-btn{z-index:5;position:absolute;bottom:20px;right:20px;box-shadow:0 4px 14px #6366f166}.completion-overlay{-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);z-index:100;text-align:center;background-color:#0b0f19d9;flex-direction:column;justify-content:center;align-items:center;padding:40px;animation:.4s fadeIn;display:flex;position:absolute;inset:0}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.completion-icon{margin-bottom:20px;font-size:64px;animation:1s infinite alternate bounce}@keyframes bounce{0%{transform:translateY(0)}to{transform:translateY(-10px)}}.completion-title{color:#fff;margin-bottom:12px;font-size:28px;font-weight:800}.completion-desc{color:var(--text-muted);max-width:400px;margin-bottom:24px;font-size:15px;line-height:1.6}.completion-reset-btn{background:linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);color:#fff;cursor:pointer;box-shadow:0 4px 15px var(--primary-glow);border:none;border-radius:8px;padding:12px 24px;font-size:15px;font-weight:700;transition:all .2s}.completion-reset-btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px #6366f166}