.code-editor-wrap{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;background:#1e1e1e}.editor-toolbar{display:flex;align-items:center;justify-content:space-between;padding:8px 12px;background:var(--surface2);border-bottom:1px solid var(--border)}.py-status{display:flex;align-items:center;gap:6px;font-size:.78rem;color:var(--text-muted)}.py-status-dot{width:8px;height:8px;border-radius:50%;background:var(--text-muted)}.status-ready .py-status-dot{background:var(--success)}.status-error .py-status-dot{background:var(--error)}.status-loading .py-status-dot{background:var(--warning);animation:pulse 1.2s infinite}@keyframes pulse{0%,to{opacity:1}50%{opacity:.3}}.run-btn{display:flex;align-items:center;gap:8px;background:var(--accent);color:#fff;border:none;border-radius:6px;padding:6px 14px;font-size:.85rem;font-weight:600;cursor:pointer;transition:background .15s}.run-btn:hover:not(:disabled){background:var(--accent-hover)}.run-btn:disabled{opacity:.5;cursor:not-allowed}.run-shortcut{font-size:.7rem;opacity:.7;font-weight:400}.output-panel{border:1px solid var(--border);border-radius:var(--radius);padding:14px 16px;min-height:80px;font-family:JetBrains Mono,Fira Code,monospace;font-size:.85rem}.output-empty{color:var(--text-muted);display:flex;align-items:center;gap:6px}.output-empty kbd{background:var(--surface2);border:1px solid var(--border);border-radius:4px;padding:1px 6px;font-size:.78rem;font-family:inherit}.output-running{display:flex;align-items:center;gap:8px;color:var(--text-muted)}.output-spinner{width:14px;height:14px;border:2px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .7s linear infinite;display:inline-block}@keyframes spin{to{transform:rotate(360deg)}}.output-ok{border-color:var(--success);background:#22c55e0d}.output-error{border-color:var(--error);background:#ef44440d}.output-label{font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;margin-bottom:8px;color:var(--text-muted)}.output-ok .output-label{color:var(--success)}.output-error .output-label{color:var(--error)}.output-text{white-space:pre-wrap;word-break:break-word;color:var(--text)}.exercise-panel{display:flex;flex-direction:column;gap:16px}.exercise-progress{display:flex;align-items:center;gap:12px}.progress-label{font-size:.78rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;color:var(--text-muted)}.progress-tabs{display:flex;gap:6px}.progress-tab{width:32px;height:32px;border-radius:50%;border:2px solid var(--border);background:var(--surface);color:var(--text-muted);font-size:.8rem;font-weight:600;cursor:pointer;transition:all .15s}.progress-tab.active{border-color:var(--accent);color:var(--accent)}.progress-tab.done{background:var(--success);border-color:var(--success);color:#fff}.progress-count{font-size:.8rem;color:var(--text-muted);margin-left:auto}.exercise-header{display:flex;flex-direction:column;gap:6px}.exercise-title{font-size:1.05rem;font-weight:600}.exercise-desc{color:var(--text-muted);font-size:.9rem;line-height:1.5}.exercise-actions{display:flex;gap:10px;align-items:center}.hint-btn{background:transparent;border:1px solid var(--border);color:var(--text-muted);padding:6px 12px;border-radius:6px;font-size:.82rem;cursor:pointer;transition:all .15s}.hint-btn:hover{border-color:var(--accent);color:var(--accent)}.next-btn{background:var(--success);border:none;color:#fff;padding:6px 16px;border-radius:6px;font-size:.85rem;font-weight:600;cursor:pointer;margin-left:auto;transition:opacity .15s}.next-btn:hover{opacity:.85}.hint-box{background:#f59e0b1a;border:1px solid rgba(245,158,11,.3);border-radius:var(--radius);padding:12px 16px;font-size:.88rem;display:flex;gap:10px;align-items:flex-start;color:var(--text)}.hint-icon{font-size:1rem;flex-shrink:0}.validation-result{display:flex;align-items:center;gap:10px;padding:12px 16px;border-radius:var(--radius);font-size:.88rem;font-weight:500}.result-ok{background:#22c55e1a;border:1px solid rgba(34,197,94,.3);color:var(--success)}.result-fail{background:#ef44441a;border:1px solid rgba(239,68,68,.3);color:var(--error)}.tutor-chat{display:flex;flex-direction:column;height:100%;border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;background:var(--surface)}.tutor-header{display:flex;align-items:center;gap:10px;padding:14px 16px;border-bottom:1px solid var(--border);background:var(--surface2)}.tutor-avatar{width:36px;height:36px;border-radius:50%;background:linear-gradient(135deg,var(--accent),#a78bfa);display:flex;align-items:center;justify-content:center;font-size:.7rem;font-weight:700;color:#fff;flex-shrink:0}.tutor-name{font-weight:600;font-size:.9rem}.tutor-subtitle{font-size:.75rem;color:var(--text-muted)}.tutor-badge{margin-left:auto;font-size:.68rem;font-weight:700;text-transform:uppercase;letter-spacing:.06em;padding:2px 8px;border-radius:99px}.tutor-badge-live{background:#22c55e26;border:1px solid rgba(34,197,94,.3);color:var(--success)}.tutor-messages{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:12px}.message{display:flex;gap:8px;align-items:flex-start}.message-user{flex-direction:row-reverse}.msg-avatar{width:28px;height:28px;border-radius:50%;background:linear-gradient(135deg,var(--accent),#a78bfa);display:flex;align-items:center;justify-content:center;font-size:.6rem;font-weight:700;color:#fff;flex-shrink:0;margin-top:2px}.msg-bubble{max-width:85%;padding:10px 14px;border-radius:12px;font-size:.88rem;line-height:1.5;background:var(--surface2);border:1px solid var(--border)}.message-user .msg-bubble{background:var(--accent);border-color:transparent;color:#fff}.msg-typing{display:flex;gap:4px;align-items:center;padding:14px}.msg-typing span{width:6px;height:6px;border-radius:50%;background:var(--text-muted);animation:typing 1s infinite}.msg-typing span:nth-child(2){animation-delay:.2s}.msg-typing span:nth-child(3){animation-delay:.4s}@keyframes typing{0%,to{opacity:.3;transform:translateY(0)}50%{opacity:1;transform:translateY(-3px)}}.tutor-input-row{display:flex;gap:8px;padding:12px;border-top:1px solid var(--border);background:var(--surface2)}.tutor-input{flex:1;background:var(--surface);border:1px solid var(--border);border-radius:8px;color:var(--text);padding:8px 12px;font-size:.88rem;font-family:inherit;resize:none;line-height:1.4;max-height:120px}.tutor-input:focus{outline:none;border-color:var(--accent)}.tutor-send{width:36px;height:36px;border-radius:8px;background:var(--accent);border:none;color:#fff;font-size:1rem;cursor:pointer;flex-shrink:0;align-self:flex-end;transition:background .15s}.tutor-send:hover:not(:disabled){background:var(--accent-hover)}.tutor-send:disabled{opacity:.4;cursor:not-allowed}.lesson-page{display:grid;grid-template-columns:380px 1fr;height:calc(100vh - 56px);overflow:hidden;width:100%}.lesson-sidebar{border-right:1px solid var(--border);overflow-y:auto;padding:28px 24px;display:flex;flex-direction:column;gap:28px}.lesson-meta{display:flex;flex-direction:column;gap:8px}.lesson-badge{display:inline-flex;background:#6c63ff26;color:var(--accent);border:1px solid rgba(108,99,255,.3);border-radius:99px;padding:2px 10px;font-size:.72rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;width:fit-content}.lesson-title{font-size:1.4rem;font-weight:700;line-height:1.3}.lesson-subtitle{color:var(--text-muted);font-size:.85rem}.lesson-sections{display:flex;flex-direction:column;gap:28px}.lesson-section{display:flex;flex-direction:column;gap:10px}.section-title{font-size:1rem;font-weight:600;color:var(--text)}.section-content{font-size:.88rem;color:var(--text-muted);line-height:1.65;white-space:pre-line}.section-content strong{color:var(--text);font-weight:600}.section-content code{background:var(--surface2);border:1px solid var(--border);border-radius:4px;padding:1px 5px;font-family:JetBrains Mono,monospace;font-size:.82em;color:#c4b5fd}.example-block{background:var(--surface2);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden}.example-label{padding:6px 12px;font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;color:var(--text-muted);border-bottom:1px solid var(--border)}.example-code{padding:12px;font-family:JetBrains Mono,Fira Code,monospace;font-size:.82rem;color:#c4b5fd;white-space:pre-wrap;line-height:1.6;overflow-x:auto}.example-try-btn{display:block;width:100%;background:transparent;border:none;border-top:1px solid var(--border);color:var(--accent);padding:8px 12px;font-size:.8rem;font-weight:600;text-align:left;cursor:pointer;transition:background .15s}.example-try-btn:hover{background:#6c63ff14}.lesson-workspace{display:flex;flex-direction:column;overflow:hidden}.workspace-tabs{display:flex;border-bottom:1px solid var(--border);background:var(--surface);padding:0 16px;gap:0}.workspace-tab{background:transparent;border:none;border-bottom:2px solid transparent;color:var(--text-muted);padding:14px 16px;font-size:.88rem;font-weight:500;cursor:pointer;transition:all .15s;white-space:nowrap}.workspace-tab:hover{color:var(--text)}.workspace-tab.active{color:var(--accent);border-bottom-color:var(--accent)}.workspace-content{flex:1;overflow-y:auto;padding:24px}.tab-sandbox{display:flex;flex-direction:column;gap:16px}.app{display:flex;flex-direction:column;min-height:100vh}.app-header{background:var(--surface);border-bottom:1px solid var(--border);padding:0 24px;height:56px;display:flex;align-items:center;position:sticky;top:0;z-index:100}.app-header-inner{display:flex;align-items:center;gap:24px;width:100%;max-width:1400px;margin:0 auto}.logo{font-size:1.2rem;font-weight:700;letter-spacing:-.5px}.logo-accent{color:var(--accent)}.breadcrumb{display:flex;align-items:center;gap:8px;font-size:.85rem;color:var(--text-muted)}.breadcrumb .sep{opacity:.4}.breadcrumb .current{color:var(--text)}.app-main{flex:1;display:flex;overflow:hidden}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--bg: #0f1117;--surface: #1a1d27;--surface2: #22263a;--border: #2e3350;--accent: #6c63ff;--accent-hover: #5a52e0;--success: #22c55e;--error: #ef4444;--warning: #f59e0b;--text: #e2e8f0;--text-muted: #8892a4;--radius: 10px}body{background:var(--bg);color:var(--text);font-family:Inter,system-ui,-apple-system,sans-serif;font-size:15px;line-height:1.6;min-height:100vh}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:var(--surface)}::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}