:root{--paper:#f7f8f4;--ink:#20332e;--muted:#65746e;--line:#dce3da;--teal:#126856;--mint:#eaf3ed;--orange:#a9512a;--peach:#fff1e5}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:var(--paper);color:var(--ink);font-family:"Yu Gothic UI","Yu Gothic","Hiragino Kaku Gothic ProN",Meiryo,sans-serif;font-size:15px;line-height:1.85}a{color:inherit;text-underline-offset:4px}header{height:78px;display:flex;align-items:center;justify-content:space-between;padding:0 4.5%;border-bottom:1px solid var(--line);background:var(--paper);position:sticky;top:0;z-index:5}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-weight:750;letter-spacing:.05em}.logo{background:var(--teal);color:white;display:grid;place-items:center;width:32px;height:32px;border-radius:9px;font-size:24px}.header-link{font-size:13px;text-decoration:none}.header-link span{margin-left:20px}.layout{max-width:1440px;display:grid;grid-template-columns:240px 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