:root {
  color-scheme: light;
  --ink: #17202a;
  --muted: #5d6874;
  --paper: #f7f4ed;
  --surface: #ffffff;
  --line: #d9d3c8;
  --accent: #255957;
  --accent-dark: #173d3b;
  --notice: #e5efe8;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font: 17px/1.65 ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

a {
  color: var(--accent);
  text-underline-offset: 0.18em;
}

a:hover,
a:focus-visible {
  color: var(--accent-dark);
}

.planning-notice {
  padding: 0.55rem 1rem;
  color: var(--accent-dark);
  background: var(--notice);
  border-bottom: 1px solid #c7d8cc;
  font-size: 0.83rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-align: center;
  text-transform: uppercase;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  padding: 1.1rem max(1.25rem, calc((100vw - 1120px) / 2));
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}

.site-brand {
  color: var(--ink);
  font-weight: 800;
  text-decoration: none;
}

.site-header nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.94rem;
  font-weight: 650;
}

.document-shell {
  width: min(860px, calc(100% - 2.5rem));
  margin: 3rem auto 5rem;
  padding: clamp(1.5rem, 4vw, 3.5rem);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: 0 16px 50px rgb(35 37 35 / 7%);
}

.document-shell h1,
.document-shell h2,
.document-shell h3 {
  line-height: 1.2;
  scroll-margin-top: 1rem;
}

.document-shell h1 {
  margin-top: 0;
  font-size: clamp(2rem, 6vw, 3.4rem);
  letter-spacing: -0.035em;
}

.document-shell h2 {
  margin-top: 2.5rem;
  padding-top: 0.5rem;
  border-top: 1px solid var(--line);
}

.document-shell img {
  max-width: 100%;
}

.document-shell code {
  padding: 0.14rem 0.34rem;
  background: #f0eee8;
  border-radius: 4px;
  font-size: 0.9em;
}

.document-shell pre {
  overflow-x: auto;
  padding: 1rem;
  background: #f0eee8;
  border-radius: 8px;
}

.document-shell pre code {
  padding: 0;
}

.document-shell table {
  display: block;
  max-width: 100%;
  overflow-x: auto;
  border-collapse: collapse;
}

.document-shell th,
.document-shell td {
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.site-footer {
  padding: 0 1.25rem 2.5rem;
  color: var(--muted);
  font-size: 0.9rem;
  text-align: center;
}

@media (max-width: 680px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.65rem;
  }

  .document-shell {
    width: min(100% - 1rem, 860px);
    margin-top: 0.5rem;
    border-radius: 10px;
  }
}