/* Chaptered website — Apple-style system look, light & dark. */
:root {
  --bg: #f2f2f7; --surface: #ffffff; --fill: rgba(118,118,128,.12);
  --label: #000000; --secondary: rgba(60,60,67,.6); --tertiary: rgba(60,60,67,.3);
  --separator: rgba(60,60,67,.18); --accent: #5856d6; --pink: #ff2d55; --orange: #ff9500; --green: #34c759;
  --radius: 22px; --shadow: 0 1px 2px rgba(0,0,0,.04), 0 8px 24px rgba(0,0,0,.06);
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #000000; --surface: #1c1c1e; --fill: rgba(118,118,128,.24);
    --label: #ffffff; --secondary: rgba(235,235,245,.6); --tertiary: rgba(235,235,245,.3);
    --separator: rgba(84,84,88,.6); --accent: #5e5ce6; --pink: #ff375f; --shadow: none;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--label);
  font: 17px/1.47 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }
.nav { position: sticky; top: 0; z-index: 10; backdrop-filter: saturate(180%) blur(20px); -webkit-backdrop-filter: saturate(180%) blur(20px);
  background: color-mix(in srgb, var(--bg) 72%, transparent); border-bottom: .5px solid var(--separator); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 52px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--label); font-weight: 600; font-size: 17px; }
.brand:hover { text-decoration: none; }
.brand img { width: 30px; height: 30px; border-radius: 7px; }
.nav-links a { margin-left: 18px; font-size: 14px; color: var(--secondary); }
h1 { font-size: 40px; line-height: 1.1; letter-spacing: -.02em; margin: 0 0 12px; font-weight: 700; }
h2 { font-size: 24px; letter-spacing: -.01em; margin: 36px 0 10px; font-weight: 700; }
h3 { font-size: 19px; margin: 24px 0 6px; font-weight: 600; }
p, li { color: var(--label); }
.muted { color: var(--secondary); }
.card { background: var(--surface); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
.button { display: inline-flex; align-items: center; gap: 8px; border: 0; border-radius: 999px; padding: 12px 22px;
  background: var(--accent); color: #fff; font: 600 17px/1 -apple-system, sans-serif; cursor: pointer; }
.button:hover { text-decoration: none; filter: brightness(1.06); }
.button.secondary { background: var(--fill); color: var(--accent); }
.footer { padding: 36px 0 48px; color: var(--secondary); font-size: 13px; }
.footer a { color: var(--secondary); margin-right: 16px; }
.legal h2 { font-size: 20px; }
.legal p, .legal li { font-size: 16px; }
@media (max-width: 600px) { h1 { font-size: 32px; } .nav-links a { margin-left: 12px; } }