:root {
  --brand: #2563eb;
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #1f2328;
  --muted: #6b7280;
  --border: #e5e7eb;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme='light']) {
    --bg: #111318;
    --surface: #1b1e24;
    --text: #e6e8eb;
    --muted: #9aa1ab;
    --border: #2c3038;
    color-scheme: dark;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.6 -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

a {
  color: var(--brand);
  text-decoration: none;
}

.wrap {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 16px;
}

.top {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.top-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  height: 60px;
}

.brand {
  font-weight: 700;
  font-size: 17px;
}

.top nav {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 14px;
}

.btn {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 8px;
  border: 1px solid var(--brand);
  background: var(--brand);
  color: #fff;
  font: inherit;
  font-size: 14px;
  cursor: pointer;
}

.btn-ghost {
  background: transparent;
  color: var(--brand);
}

.hero {
  padding: 64px 0 40px;
}

.hero h1 {
  margin: 0 0 12px;
  font-size: clamp(28px, 5vw, 40px);
  line-height: 1.2;
}

.hero p {
  margin: 0 0 24px;
  color: var(--muted);
  font-size: 17px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero .hint {
  margin-top: 20px;
  font-size: 13px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.grid article,
.embed {
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.grid h2,
.embed h2 {
  margin: 0 0 8px;
  font-size: 16px;
}

.grid p,
.embed p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.embed {
  margin: 24px 0;
}

.embed pre {
  margin: 12px 0 0;
  padding: 12px;
  border-radius: 8px;
  background: var(--bg);
  border: 1px solid var(--border);
  overflow-x: auto;
  font-size: 13px;
}

.foot {
  padding: 24px 16px 96px;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 560px) {
  .top nav a:not(.btn) {
    display: none;
  }
}