:root {
  --bg: #ffffff;
  --sidebar-bg: #f7f8fa;
  --text: #1a202c;
  --text-muted: #57606a;
  --border: #e5e7eb;
  --accent: #166e3f;
  --accent-soft: #e8f4ee;
  --green: #166e3f;
  --green-soft: #e8f4ee;
  --amber: #b45309;
  --amber-soft: #fdf3e3;
  --red: #b91c1c;
  --red-soft: #fdeaea;
  --info: #1d4ed8;
  --info-soft: #e8eefc;
  --sidebar-w: 264px;
  --code-bg: #f1f3f5;
}

[data-theme="dark"] {
  --bg: #0f1115;
  --sidebar-bg: #161a1f;
  --text: #e6e9ef;
  --text-muted: #98a1ad;
  --border: #262b33;
  --accent: #3ecf8e;
  --accent-soft: #12261c;
  --green: #3ecf8e;
  --green-soft: #12261c;
  --amber: #f0b455;
  --amber-soft: #2a2113;
  --red: #f87171;
  --red-soft: #2a1414;
  --info: #7ea6f8;
  --info-soft: #131c2c;
  --code-bg: #1c2128;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: "Plus Jakarta Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* Scrollbars — 3px everywhere */
::-webkit-scrollbar { width: 3px; height: 3px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }

/* Layout */
.layout { display: flex; min-height: 100vh; }

/* Sidebar */
.sidebar {
  width: var(--sidebar-w);
  min-width: var(--sidebar-w);
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  padding: 24px 0 40px;
  display: flex;
  flex-direction: column;
}
.sidebar::-webkit-scrollbar { width: 3px; }
.sidebar::-webkit-scrollbar-thumb { background: #d1d5db; border-radius: 2px; }
[data-theme="dark"] .sidebar::-webkit-scrollbar-thumb { background: #333a44; }

.sidebar-brand {
  padding: 0 20px 20px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 12px;
}
.sidebar-brand .logo {
  font-weight: 800;
  font-size: 15px;
  color: var(--text);
  letter-spacing: -0.01em;
}
.sidebar-brand .logo span { color: var(--accent); }
.sidebar-brand .sub {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 2px;
}

.theme-toggle {
  margin: 0 20px 14px;
  padding: 7px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  color: var(--text-muted);
  font-family: inherit;
  font-size: 12.5px;
  font-weight: 600;
  cursor: pointer;
  transition: all .15s;
  display: flex;
  align-items: center;
  gap: 7px;
}
.theme-toggle:hover { color: var(--accent); border-color: var(--accent); }

.nav-group { margin-bottom: 20px; }
.nav-group-title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  font-weight: 700;
  padding: 6px 20px 4px;
}
.nav-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 20px;
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
  line-height: 1.4;
  border-left: 2px solid transparent;
}
.nav-item:hover { background: var(--code-bg); }
.nav-item.active {
  color: var(--accent);
  font-weight: 700;
  border-left-color: var(--accent);
  background: var(--accent-soft);
}
.nav-item .ico { font-size: 14px; width: 16px; text-align: center; }

/* Main content */
.main {
  flex: 1;
  min-width: 0;
  padding: 40px 56px 80px;
  max-width: 920px;
}
.content { width: 100%; }

/* Page title */
.page-title { margin-bottom: 28px; }
.eyebrow {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 6px;
}
h1 {
  font-size: 34px;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 10px;
}
.lede {
  font-size: 17px;
  color: var(--text-muted);
  line-height: 1.6;
  max-width: 720px;
}

h2 {
  font-size: 23px;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 40px 0 14px;
  padding-top: 8px;
}
h2 .hash { color: var(--accent); font-weight: 800; margin-right: 6px; }
h3 {
  font-size: 17px;
  font-weight: 700;
  margin: 26px 0 10px;
}
p { margin-bottom: 14px; }
ul, ol { margin: 0 0 16px 22px; }
li { margin-bottom: 7px; }
li > ul, li > ol { margin-top: 7px; }
strong { font-weight: 700; }

a { color: var(--accent); text-decoration: none; font-weight: 600; }
a:hover { text-decoration: underline; }

/* Callouts — BOLD brand-colored, never subtle gray */
.callout {
  display: flex;
  gap: 12px;
  border-radius: 10px;
  padding: 16px 18px;
  margin: 20px 0;
  border-left: 5px solid;
  font-weight: 600;
}
.callout p { margin-bottom: 6px; }
.callout p:last-child { margin-bottom: 0; }
.callout .ico { font-size: 18px; line-height: 1.5; }
.callout.good { background: var(--green-soft); border-color: var(--green); color: var(--text); }
.callout.good strong { color: var(--green); }
.callout.warn { background: var(--amber-soft); border-color: var(--amber); color: var(--text); }
.callout.warn strong { color: var(--amber); }
.callout.bad { background: var(--red-soft); border-color: var(--red); color: var(--text); }
.callout.bad strong { color: var(--red); }
.callout.info { background: var(--info-soft); border-color: var(--info); color: var(--text); }
.callout.info strong { color: var(--info); }
.callout .callout-title {
  font-weight: 800;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}
.callout.good .callout-title { color: var(--green); }
.callout.warn .callout-title { color: var(--amber); }
.callout.bad .callout-title { color: var(--red); }
.callout.info .callout-title { color: var(--info); }

/* Stat cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
  margin: 22px 0;
}
.card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
  background: var(--bg);
}
.card .label {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 6px;
}
.card .value {
  font-size: 27px;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--accent);
  line-height: 1.1;
}
.card .value.red { color: var(--red); }
.card .value.amber { color: var(--amber); }
.card .hint { font-size: 12.5px; color: var(--text-muted); margin-top: 6px; line-height: 1.45; }

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0 24px;
  font-size: 14.5px;
}
th {
  text-align: left;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  border-bottom: 2px solid var(--border);
  padding: 9px 12px 9px 0;
}
td {
  border-bottom: 1px solid var(--border);
  padding: 10px 12px 10px 0;
  vertical-align: top;
  line-height: 1.5;
}
tr:last-child td { border-bottom: none; }
td strong { font-weight: 800; }
.table-hl td { background: var(--accent-soft); }
.table-hl td:first-child { border-radius: 8px 0 0 8px; }
.table-hl td:last-child { border-radius: 0 8px 8px 0; }

/* Badges */
.badge {
  display: inline-block;
  font-size: 11.5px;
  font-weight: 800;
  padding: 2px 9px;
  border-radius: 999px;
  letter-spacing: 0.02em;
  white-space: nowrap;
}
.badge.green { background: var(--green-soft); color: var(--green); }
.badge.amber { background: var(--amber-soft); color: var(--amber); }
.badge.red { background: var(--red-soft); color: var(--red); }
.badge.gray { background: var(--code-bg); color: var(--text-muted); }

/* Code / formula blocks */
.code {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px 18px;
  font-size: 13.5px;
  line-height: 1.7;
  overflow-x: auto;
  margin: 16px 0 22px;
  white-space: pre;
  font-family: "Plus Jakarta Sans", monospace;
  font-weight: 600;
}

/* Small source notes */
.src {
  font-size: 12.5px;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  padding-top: 10px;
  margin-top: 18px;
}

/* Page footer nav */
.pagenav {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}
.pagenav a {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  max-width: 48%;
}
.pagenav a:hover { border-color: var(--accent); text-decoration: none; background: var(--accent-soft); }
.pagenav .dir { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-muted); }
.pagenav .ttl { font-size: 14px; font-weight: 700; color: var(--accent); }
.pagenav .next { margin-left: auto; text-align: right; }

@media (max-width: 860px) {
  .layout { flex-direction: column; }
  .sidebar { position: static; width: 100%; min-width: 100%; height: auto; padding-bottom: 10px; }
  .main { padding: 28px 20px 60px; max-width: 100%; }
  h1 { font-size: 27px; }
}