*{box-sizing:border-box}body{margin:0;background:#f4f8f8;color:#17333b;font:16px/1.75 system-ui,sans-serif}header,main,footer{max-width:850px;margin:auto;padding:24px}header{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}a{color:#087d76;text-underline-offset:3px}main{background:white;border:1px solid #dce8e8;border-radius:18px;padding:clamp(20px,5vw,48px)}h1{line-height:1.2;font-size:clamp(28px,5vw,40px)}h2{font-size:21px;margin-top:30px}nav{display:flex;gap:18px;flex-wrap:wrap}.note{padding:16px;background:#fff7df;border-radius:10px;color:#68520b}footer{font-size:14px}a:focus-visible{outline:3px solid #138b80;outline-offset:4px}