:root {
  --ground: #EEF4FB;
  --ground-2: #F7FAFE;
  --card: #FFFFFF;
  --ink: #14202E;
  --muted: #5B6779;
  --line: rgba(20, 32, 46, 0.09);
  --accent: #0A60CC;
  --accent-2: #12B5D6;
  --accent-soft: rgba(10, 96, 204, 0.09);
}
@media (prefers-color-scheme: dark) {
  :root {
    --ground: #0F141D;
    --ground-2: #141B26;
    --card: #1A2230;
    --ink: #E8EDF5;
    --muted: #9AA7BA;
    --line: rgba(255, 255, 255, 0.08);
    --accent: #6EA8FF;
    --accent-2: #4FD1E8;
    --accent-soft: rgba(110, 168, 255, 0.12);
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: linear-gradient(180deg, var(--ground), var(--ground-2) 60%);
  background-attachment: fixed;
  color: var(--ink);
  font-family: "Manrope", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.6;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 860px; margin: 0 auto; padding: 0 20px; }

header.top { padding: 22px 0; }
header.top .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 19px; color: var(--ink); }
.brand img { width: 34px; height: 34px; border-radius: 9px; box-shadow: 0 2px 8px rgba(10, 60, 140, 0.18); }
.brand:hover { text-decoration: none; }
nav.links { display: flex; gap: 18px; font-weight: 600; font-size: 15px; }
nav.links a { color: var(--muted); }
nav.links a.on, nav.links a:hover { color: var(--accent); text-decoration: none; }

.hero { text-align: center; padding: 48px 0 28px; }
.hero img { width: 112px; height: 112px; border-radius: 26px; box-shadow: 0 18px 40px rgba(10, 60, 140, 0.22); }
.hero h1 { font-size: clamp(34px, 6vw, 52px); line-height: 1.08; letter-spacing: -0.02em; margin: 26px 0 12px; }
.hero h1 span { background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero p { color: var(--muted); font-size: 19px; max-width: 560px; margin: 0 auto; }
.pill { display: inline-flex; align-items: center; gap: 8px; margin-top: 26px; padding: 11px 20px; border-radius: 999px; background: var(--accent-soft); color: var(--accent); font-weight: 700; font-size: 15px; }

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 14px; padding: 30px 0 10px; }
.card { background: var(--card); border-radius: 20px; padding: 22px; box-shadow: 0 1px 2px rgba(10, 30, 60, 0.05), 0 10px 26px rgba(10, 40, 90, 0.07); border: 1px solid var(--line); }
.card .ic { width: 40px; height: 40px; border-radius: 12px; background: var(--accent-soft); display: flex; align-items: center; justify-content: center; margin-bottom: 12px; }
.card .ic svg { width: 21px; height: 21px; stroke: var(--accent); fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.55; }

.doc { padding-top: 26px; padding-bottom: 40px; }
.doc h1 { font-size: clamp(30px, 5vw, 40px); letter-spacing: -0.015em; margin: 10px 0 4px; }
.doc .date { color: var(--muted); font-size: 15px; margin-bottom: 26px; }
.doc .card { margin-bottom: 14px; }
.doc h2 { font-size: 20px; margin: 0 0 8px; }
.doc p, .doc li { color: var(--ink); font-size: 16px; }
.doc p { margin: 0 0 10px; }
.doc ul { margin: 0 0 10px; padding-left: 20px; }
.doc li { margin-bottom: 6px; }
.doc .muted { color: var(--muted); }
.callout { background: var(--accent-soft); border-radius: 14px; padding: 14px 16px; margin: 6px 0 12px; font-size: 15.5px; }

details { border-top: 1px solid var(--line); padding: 14px 0; }
details:first-of-type { border-top: 0; padding-top: 2px; }
summary { cursor: pointer; font-weight: 700; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--accent); font-weight: 800; }
details[open] summary::after { content: "–"; }
details p, details ol, details ul { margin: 10px 0 0; color: var(--muted); font-size: 15.5px; }
details ol, details ul { padding-left: 20px; }

footer { padding: 30px 0 46px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px; border-top: 1px solid var(--line); padding-top: 22px; }
footer nav { display: flex; gap: 16px; }
footer a { color: var(--muted); }

@media (max-width: 520px) {
  nav.links { gap: 12px; font-size: 14px; }
  .brand span { display: none; }
}