:root{--bg:#f6f7f9;--surface:#fff;--text:#1a1d26;--muted:#667085;--border:#e4e7ec;--primary:#2563eb;--primary-dark:#1d4ed8;--primary-soft:#eff4ff;--accent:#0f9d6a;--accent-soft:#e8f7f1;--danger:#dc2626;--danger-soft:#fef2f2;--warning:#b45309;--warning-soft:#fffbeb;--radius:12px;--shadow:0 1px 2px rgba(16,24,40,.06),0 1px 3px rgba(16,24,40,.1);--shadow-lg:0 12px 32px -8px rgba(16,24,40,.16)}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;font-family:Hiragino Kaku Gothic ProN,Hiragino Sans,Yu Gothic UI,Noto Sans JP,Meiryo,-apple-system,BlinkMacSystemFont,sans-serif;color:var(--text);background:var(--bg);line-height:1.7;font-size:16px}a{color:var(--primary);text-decoration:none}a:hover{text-decoration:underline}.container{max-width:1040px;margin:0 auto;padding:0 20px}.site-header{background:var(--surface);border-bottom:1px solid 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