:root{--bg:#f5f7fb;--paper:#ffffff;--ink:#161b26;--ink-soft:#5c6478;--accent:#2f8fe0;--accent-dark:#1c6dc2;--accent-soft:#e6f2fd;--border:#e3e7ef;--border-strong:#d7dce6;--shadow-xs:0 1px 2px rgba(22,27,38,0.05);--shadow-sm:0 2px 6px rgba(22,27,38,0.05),0 1px 2px rgba(22,27,38,0.04);--shadow-md:0 10px 24px -8px rgba(22,27,38,0.16),0 2px 6px rgba(22,27,38,0.05);--shadow-lg:0 20px 40px -12px rgba(22,27,38,0.2),0 4px 10px rgba(22,27,38,0.06);--shadow-accent:0 16px 32px -10px rgba(47,143,224,0.35)}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}body{margin:0;color:var(--ink);background-color:var(--bg);font-family:var(--font-body),"Segoe UI",sans-serif;font-size:16px;line-height:1.55}h1,h2,h3{font-family:var(--font-display),Georgia,serif;font-weight:600;line-height:1.15;margin:0 0 .5em;letter-spacing:-.01em}a{color:inherit}kbd{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.85em;background:var(--paper);border:solid 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