:root {
  --bg: #ffffff;
  --fg: #111418;
  --muted: #5b6370;
  --border: #e5e7eb;
  --accent: #2563eb;
  --accent-fg: #ffffff;
  --code-bg: #0f172a;
  --code-fg: #e2e8f0;
  --max: 760px;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.6;
  font-size: 17px;
}

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }

header.site {
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
  background: #fff;
}
header.site .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
header.site a.logo {
  font-weight: 700;
  font-size: 18px;
  color: var(--fg);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
header.site a.logo svg { width: 22px; height: 22px; }
header.site nav { display: flex; gap: 18px; flex-wrap: wrap; }
header.site nav a { color: var(--muted); text-decoration: none; font-size: 14px; }
header.site nav a:hover { color: var(--accent); }

main { padding: 36px 0 64px; }

h1 { font-size: 32px; line-height: 1.2; margin: 0 0 16px; letter-spacing: -0.01em; }
h2 { font-size: 22px; line-height: 1.3; margin: 32px 0 12px; letter-spacing: -0.01em; }
h3 { font-size: 18px; margin: 24px 0 8px; }
p { margin: 0 0 16px; }
a { color: var(--accent); }
a:hover { text-decoration: underline; }

ul, ol { padding-left: 22px; margin: 0 0 16px; }
li { margin-bottom: 6px; }

.lede { font-size: 19px; color: var(--muted); margin-bottom: 24px; }

.card {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  margin: 16px 0;
  background: #fafbfc;
}

.tool {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0;
  overflow: hidden;
  background: #fff;
  margin: 8px 0 24px;
}
.tool textarea {
  width: 100%;
  min-height: 320px;
  border: 0;
  padding: 16px;
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 14px;
  line-height: 1.55;
  resize: vertical;
  color: var(--fg);
  outline: none;
}
.tool .toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  border-top: 1px solid var(--border);
  background: #f6f7f9;
  font-size: 13px;
  color: var(--muted);
}
.tool .toolbar .stats span { margin-right: 12px; }
.tool .toolbar button {
  background: var(--accent);
  color: var(--accent-fg);
  border: 0;
  border-radius: 6px;
  padding: 7px 12px;
  font-size: 13px;
  cursor: pointer;
  font-weight: 500;
}
.tool .toolbar button.secondary {
  background: #fff;
  color: var(--fg);
  border: 1px solid var(--border);
}
.tool .toolbar button:hover { opacity: 0.9; }

pre, code {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}
pre {
  background: var(--code-bg);
  color: var(--code-fg);
  padding: 14px 16px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 13px;
}
code { background: #f1f3f5; padding: 1px 5px; border-radius: 4px; font-size: 0.92em; }
pre code { background: transparent; padding: 0; }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  margin: 16px 0;
}
.grid a {
  display: block;
  padding: 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  text-decoration: none;
  color: var(--fg);
  background: #fff;
}
.grid a:hover { border-color: var(--accent); }
.grid a strong { display: block; margin-bottom: 4px; }
.grid a span { color: var(--muted); font-size: 13px; }

footer.site {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  color: var(--muted);
  font-size: 13px;
}
footer.site .wrap { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; }
footer.site nav a { color: var(--muted); text-decoration: none; margin-right: 14px; }
footer.site nav a:hover { color: var(--accent); }

.breadcrumb { font-size: 13px; color: var(--muted); margin-bottom: 12px; }
.breadcrumb a { color: var(--muted); }

table { width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 15px; }
th, td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--border); }
th { font-weight: 600; }

.note { background: #fff8e1; border-left: 3px solid #f59e0b; padding: 10px 14px; border-radius: 4px; margin: 14px 0; }

@media (max-width: 600px) {
  h1 { font-size: 26px; }
  .lede { font-size: 17px; }
  body { font-size: 16px; }
}