@import"https://fonts.googleapis.com/css2?family=Source+Serif+4:ital,opsz,wght@0,8..60,300..900;1,8..60,300..900&family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap";:root{--c-bg: #fefefe;--c-bg-alt: #f8fafc;--c-bg-interactive: linear-gradient(135deg, #eef2ff 0%, #f0f0ff 50%, #eef6ff 100%);--c-text: #0f172a;--c-text-2: #475569;--c-text-3: #94a3b8;--c-accent: #6366f1;--c-accent-hover: #4f46e5;--c-accent-light: #e0e7ff;--c-accent-glow: rgba(99, 102, 241, .15);--c-border: #e2e8f0;--c-border-interactive: #c7d2fe;--c-exercise-bg: #fffbeb;--c-exercise-border: #f59e0b;--c-exercise-text: #b45309;--c-tooltip-bg: #1e293b;--c-tooltip-text: #e2e8f0;--c-tooltip-arrow: #1e293b;--c-nav-bg: rgba(254, 254, 254, .88);--f-body: "Source Serif 4", Georgia, "Times New Roman", serif;--f-ui: "Inter", system-ui, -apple-system, sans-serif;--f-mono: "JetBrains Mono", "SF Mono", "Fira Code", monospace;--w-content: 720px;--w-wide: 960px;--w-full: 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