:root{--bg:#FBFBFD;--ink:#1D1D1F;--mute:#6E6E73;--line:#E8E8ED;--blue:#0071E3}
*{margin:0;padding:0;box-sizing:border-box}
body{background:var(--bg);color:var(--ink);font-family:'Inter',-apple-system,BlinkMacSystemFont,'SF Pro Text','Helvetica Neue',sans-serif;line-height:1.65;-webkit-font-smoothing:antialiased}
a{color:var(--blue);text-decoration:none}a:hover{text-decoration:underline}
nav{position:sticky;top:0;z-index:50;display:flex;align-items:center;justify-content:space-between;padding:0 5vw;height:52px;background:rgba(251,251,253,.8);backdrop-filter:blur(20px) saturate(1.8);border-bottom:1px solid var(--line)}
.logo{font-weight:700;font-size:17px;letter-spacing:-.02em;color:var(--ink);display:flex;align-items:center;gap:8px}
.logo-mark{display:inline-flex;gap:2.5px}.logo-mark i{width:6px;height:9px;border-radius:2px;display:block}
.logo-mark i:nth-child(1){background:#FF453A;transform:rotate(14deg)}.logo-mark i:nth-child(2){background:#FFD60A;transform:rotate(-10deg);margin-top:3px}.logo-mark i:nth-child(3){background:#30D158;transform:rotate(26deg)}
nav a.back{font-size:13.5px;color:var(--mute);font-weight:500}nav a.back:hover{color:var(--ink);text-decoration:none}
main{max-width:720px;margin:0 auto;padding:70px 5vw 90px}
h1{font-size:clamp(34px,5vw,46px);letter-spacing:-.03em;font-weight:800;line-height:1.1;margin-bottom:10px}
.meta{color:var(--mute);font-size:14px;margin-bottom:44px}
h2{font-size:19px;font-weight:700;letter-spacing:-.015em;margin:40px 0 12px}
h3{font-size:15.5px;font-weight:600;margin:22px 0 8px}
p,li{font-size:15.5px;color:#3A3A3C}p{margin-bottom:14px}
ul{margin:0 0 14px 22px}li{margin-bottom:6px}
.callout{background:#F5F5F7;border-radius:14px;padding:18px 22px;margin:18px 0;font-size:14.5px}
footer{border-top:1px solid var(--line);padding:32px 5vw;display:flex;justify-content:space-between;flex-wrap:wrap;gap:14px;font-size:12.5px;color:var(--mute);max-width:1100px;margin:0 auto}
footer .flinks{display:flex;gap:22px}footer a{color:var(--mute)}footer a:hover{color:var(--ink)}
@media(max-width:600px){main{padding:50px 6vw 70px}}