:root{color-scheme:light;font-family:system-ui,-apple-system,"Segoe UI","Noto Sans JP",sans-serif;color:#192a39;background:#f6f8fb}*{box-sizing:border-box}body{margin:0}header,main,footer{max-width:820px;margin:auto;padding:28px 24px}header{display:flex;align-items:center;justify-content:space-between;gap:16px;border-bottom:1px solid #d9e1ea}a{color:#155bb5;text-underline-offset:4px}header a:first-child{color:#192a39;font-size:19px;font-weight:700;text-decoration:none}nav{display:flex;gap:18px;font-size:14px}main{padding-top:46px;padding-bottom:42px}h1{font-size:clamp(28px,5vw,38px);line-height:1.35;margin:0 0 20px}h2{font-size:20px;margin:32px 0 10px}p,li{font-size:16px;line-height:1.9}ul{padding-left:24px}.lead{font-size:19px;color:#3c5268}.tag{font-size:13px;font-weight:600;color:#456279;letter-spacing:.04em}.note{padding:16px 20px;border-left:3px solid #2869bc;background:#eaf1fb}footer{border-top:1px solid #d9e1ea;font-size:13px;color:#556b7f}@media(max-width:540px){header{align-items:flex-start;flex-direction:column}main{padding-top:32px}}