:root {
  --bg: #f7f6fc;
  --surface: #ffffff;
  --text: #1b1d29;
  --text-2: #5c6070;
  --muted: #8b8fa3;
  --primary: #6c4ae0;
  --primary-weak: #efeafc;
  --border: #e7e5f2;
  --radius: 16px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}

header.site {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 8px;
}

.logo {
  width: 42px; height: 42px;
  border-radius: 12px;
  display: grid; place-items: center;
  font-size: 22px;
  background: linear-gradient(135deg, #7c5cff, #b491ff);
}

.brand { font-weight: 700; font-size: 18px; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 26px;
  margin-top: 20px;
  box-shadow: 0 1px 2px rgba(20,20,40,.04), 0 8px 30px rgba(20,20,40,.05);
}

h1 { font-size: 26px; margin: 8px 0 2px; }
h2 { font-size: 19px; margin: 28px 0 6px; }
h3 { font-size: 16px; margin: 18px 0 4px; }

.effective { color: var(--muted); font-size: 14px; margin-bottom: 4px; }

p, li { color: var(--text-2); }
strong { color: var(--text); }

ul { padding-left: 20px; }
li { margin: 4px 0; }

.langnav {
  display: inline-flex;
  gap: 4px;
  background: var(--primary-weak);
  border-radius: 999px;
  padding: 4px;
  margin: 12px 0 4px;
}
.langnav a {
  padding: 6px 16px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
}
.langnav a.active { background: var(--primary); color: #fff; }

.nav {
  display: flex;
  gap: 18px;
  margin-top: 10px;
  font-size: 14px;
  font-weight: 600;
}

.divider {
  height: 1px;
  background: var(--border);
  margin: 40px 0;
  border: 0;
}

.callout {
  background: var(--primary-weak);
  border: 1px solid #d9cffb;
  border-radius: 12px;
  padding: 14px 16px;
  margin: 16px 0;
}
.callout p { color: var(--text); margin: 0; }

footer {
  color: var(--muted);
  font-size: 13px;
  text-align: center;
  margin-top: 36px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14121f;
    --surface: #1c1930;
    --text: #edecf5;
    --text-2: #b7b8c9;
    --muted: #8a8ca0;
    --border: #2a2740;
    --primary-weak: #241d43;
  }
  .callout { border-color: #3a3160; }
}