@font-face {
  font-family: "Geist";
  src: url("fonts/Geist-Variable.woff2") format("woff2");
  font-weight: 100 900;
  font-display: swap;
}

:root {
  --sky-50: #F1F2F4;
  --sky-100: #E3E5E9;
  --sky-200: #C8CCD3;
  --sky-500: #16181C;
  --sky-600: #0A0A0A;
  --ink: #0C1A2E;
  --ink-2: #44536B;
  --ink-3: #5B6A80;
  --surface: #FCFDFE;
  --page: #FFFFFF;
  --hairline: rgba(12, 26, 46, 0.07);
  --shadow: 0 16px 30px -18px rgba(12, 60, 120, 0.45), 0 1px 3px rgba(12, 60, 120, 0.08);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--page);
  color: var(--ink);
  font-family: "Geist", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.55;
}

a { color: var(--sky-600); font-weight: 700; text-decoration: none; }
a:hover { text-decoration: underline; }
p a, li a { text-decoration: underline; text-decoration-thickness: 1.5px; text-underline-offset: 3px; }

.wrap { max-width: 980px; margin: 0 auto; padding: 0 24px; }

header.site {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 28px 0 8px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 22px;
  font-weight: 900;
  letter-spacing: -0.6px;
}
.brand:hover { text-decoration: none; }
.brand img { width: 32px; height: 32px; border-radius: 8px; }
.brand img.wordmark { width: auto; height: 22px; border-radius: 0; }

nav.site { display: flex; gap: 24px; }
nav.site a { color: var(--ink-3); font-size: 15px; font-weight: 700; }
nav.site a[aria-current="page"] { color: var(--ink); font-weight: 800; }

h1 {
  margin: 44px 0 12px;
  font-size: clamp(38px, 7vw, 56px);
  font-weight: 900;
  letter-spacing: -0.045em;
  line-height: 1.02;
}

h2 {
  margin: 34px 0 8px;
  font-size: 20px;
  font-weight: 900;
  letter-spacing: -0.4px;
}

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

.lede { font-size: 18px; color: var(--ink-2); margin: 0 0 30px; }

.topics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: start;
  gap: 18px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: 20px 22px 8px;
}

.card h3 { margin: 0 0 8px; font-size: 18px; font-weight: 900; letter-spacing: -0.3px; }

details { border-top: 1px solid var(--hairline); }
summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  min-height: 44px;
  font-size: 15px;
  font-weight: 650;
  color: var(--ink);
}
summary::-webkit-details-marker { display: none; }
summary::after { content: "›"; color: var(--ink-3); font-size: 20px; transition: transform 0.2s; }
details[open] summary::after { transform: rotate(90deg); }
details p { margin: 0 0 14px; font-size: 15px; }

.help {
  margin: 22px 0 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 18px 18px 22px;
  border-radius: 22px;
  background: var(--sky-50);
}
.help p { margin: 0; color: var(--ink-2); }
.help b { color: var(--ink); }

.button {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0 18px;
  height: 44px;
  border-radius: 22px;
  background: var(--ink);
  color: #FFFFFF;
  font-size: 14px;
  font-weight: 800;
  white-space: nowrap;
}
.button:hover { text-decoration: none; opacity: 0.9; }

.short {
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: 18px 22px 6px;
  margin: 26px 0 10px;
}
.short .label { font-size: 12px; font-weight: 800; letter-spacing: 0.08em; color: var(--ink-3); }
.short ul { padding-left: 18px; }

.updated { color: var(--ink-3); font-size: 15px; margin: 0; }

.legal { max-width: 720px; }
.legal li { margin-bottom: 6px; }

/* A detail that isn't final yet. */
.fill:empty::before,
.fill.todo {
  background: var(--sky-100);
  color: var(--ink);
  border-radius: 5px;
  padding: 0 4px;
  font-weight: 600;
}
.fill:empty::before { content: attr(data-label); }

footer.site {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  margin: 56px 0 0;
  padding: 22px 0 34px;
  border-top: 1px solid var(--hairline);
  font-size: 13.5px;
  color: var(--ink-3);
}
footer.site a { color: var(--ink-3); font-weight: 600; }

@media (max-width: 720px) {
  .topics { grid-template-columns: 1fr; }
  .help { flex-direction: column; align-items: flex-start; }
  nav.site { gap: 16px; }
}