:root{--bg:#F7FAF9;--card:#fff;--ink:#14231F;--mute:#4A5E58;--line:#D3E0DC;--brand:#0F766E;--brandink:#fff;--soft:#E3F2EF}
@media (prefers-color-scheme:dark){:root{--bg:#0E1715;--card:#16231F;--ink:#E8F1EE;--mute:#9DB3AC;--line:#2A3D38;--brand:#4FD1C0;--brandink:#0E1715;--soft:#1B2D29}}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--ink);font:18px/1.6 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif}
header,main,footer{max-width:760px;margin:0 auto;padding:0 20px}
header{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;padding-top:20px;padding-bottom:12px;border-bottom:1px solid var(--line)}
.logo{font-weight:800;font-size:24px;color:var(--ink);text-decoration:none}
nav a{margin-left:16px;color:var(--brand);font-weight:600;text-decoration:none}
nav a:hover,nav a:focus{text-decoration:underline}
a{color:var(--brand)}
h1{font-size:34px;line-height:1.2;margin:32px 0 12px}
h2{font-size:24px;margin:32px 0 8px}
p,li{color:var(--ink)}
.lead{font-size:21px;color:var(--mute)}
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px 20px;margin:16px 0}
.sms{background:var(--soft);border-left:5px solid var(--brand);border-radius:10px;padding:12px 16px;margin:12px 0;font-family:ui-monospace,Menlo,Consolas,monospace;font-size:16px}
.who{font-size:14px;color:var(--mute);font-family:system-ui,sans-serif;margin-bottom:4px}
footer{padding-top:24px;padding-bottom:40px;margin-top:40px;border-top:1px solid var(--line);color:var(--mute);font-size:15px}
footer a{margin-right:14px}
.updated{color:var(--mute);font-size:15px}
:focus-visible{outline:3px solid var(--brand);outline-offset:2px}