.python-page{font-family:var(--font);background:var(--bg);color:var(--text);line-height:1.75;font-size:15px;-webkit-font-smoothing:antialiased}.python-page .lesson{display:none}.python-page .lesson.show{display:block}:root{--bg: #faf9f6;--surface: #ffffff;--surface-alt: #f5f3ee;--text: #1a1a2e;--text-muted: #6b7280;--text-light: #9ca3af;--accent: #4f46e5;--accent-light: #eef2ff;--accent-dark: #3730a3;--amber: #d97706;--amber-light: #fef3c7;--success: #059669;--success-light: #d1fae5;--error: #dc2626;--error-light: #fee2e2;--border: #e5e7eb;--border-strong: #d1d5db;--code-bg: #1e1e3f;--code-text: #d4d4ff;--radius: 14px;--radius-sm: 8px;--shadow-sm: 0 1px 2px rgba(0,0,0,.05);--shadow: 0 2px 8px rgba(0,0,0,.06);--shadow-lg: 0 8px 30px rgba(0,0,0,.08);--sidebar-w: 290px;--font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", "Segoe UI", sans-serif;--mono: "JetBrains Mono", "SF Mono", "Fira Code", Consolas, 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