* { box-sizing: border-box; }
body { margin: 0; font-family: "Segoe UI", "Hiragino Sans", "Yu Gothic UI", Meiryo, sans-serif; color: #1e293b; line-height: 1.9; background: #f8fafc; }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }
header { background: #fff; border-bottom: 1px solid #e2e8f0; }
header .wrap { height: 60px; display: flex; align-items: center; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: inherit; text-decoration: none; }
.logo { width: 28px; height: 28px; border-radius: 50%; background: #2563eb; color: #fff; display: grid; place-items: center; font-family: Georgia, serif; }
main { background: #fff; margin: 28px auto; padding: 32px 36px; border: 1px solid #e2e8f0; border-radius: 14px; font-size: 15px; }
h1 { font-size: 24px; margin: 0 0 18px; }
h2 { font-size: 17px; margin: 28px 0 6px; padding-left: 10px; border-left: 4px solid #2563eb; }
ol, ul { padding-left: 22px; }
a { color: #2563eb; }
.date { color: #64748b; font-size: 13px; margin: 4px 0; }
.date:first-of-type { margin-top: 30px; }
footer { text-align: center; color: #64748b; font-size: 13px; padding: 10px 20px 40px; }
footer a { color: #64748b; }
@media (max-width: 520px) { main { padding: 22px 18px; margin: 16px 10px; } }