:root {
  --bg:      #ffffff;
  --bg-nav:  #f8f8f8;
  --bg-code: #f4f4f4;
  --border:  #cccccc;
  --text:    #000000;
  --dim:     #555555;
  --link:    #0000cc;
  --nav-w:   200px;
  --sans:    Arial, Helvetica, sans-serif;
  --serif:   "Times New Roman", Times, serif;
  --mono:    "Courier New", Courier, monospace;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 15px; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--serif);
  line-height: 1.5;
  display: flex;
  min-height: 100vh;
}

#nav {
  width: var(--nav-w);
  min-height: 100vh;
  background: var(--bg-nav);
  border-right: 1px solid var(--border);
  padding: 1rem 0 3rem;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  flex-shrink: 0;
  font-family: var(--sans);
}

.nav-logo {
  display: block;
  font-size: 0.88rem;
  font-weight: bold;
  color: var(--text);
  padding: 0.5rem 0.85rem 0.75rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0.5rem;
  text-decoration: none;
}

.nav-logo small {
  display: block;
  font-size: 0.68rem;
  font-weight: normal;
  color: var(--dim);
  margin-top: 0.1rem;
}

.nav-section {
  display: block;
  font-size: 0.63rem;
  font-weight: bold;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--dim);
  padding: 0.85rem 0.85rem 0.2rem;
}

#nav ul { list-style: none; }

#nav a {
  display: block;
  color: var(--link);
  text-decoration: none;
  padding: 0.17rem 0.85rem 0.17rem 1rem;
  border-left: 2px solid transparent;
  font-size: 0.77rem;
}

#nav a:hover { text-decoration: underline; }
#nav a.active { border-left-color: #000; color: #000; font-weight: bold; }

#content {
  flex: 1;
  min-width: 0;
  padding: 2rem 3.5rem 5rem;
  max-width: 900px;
}

.breadcrumb {
  font-family: var(--sans);
  font-size: 0.72rem;
  color: var(--dim);
  margin-bottom: 1.5rem;
}
.breadcrumb a { color: var(--link); }

h1 {
  font-family: var(--sans);
  font-size: 1.55rem;
  font-weight: bold;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.3rem;
  margin-bottom: 1rem;
}

h2 {
  font-family: var(--sans);
  font-size: 1.05rem;
  font-weight: bold;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.15rem;
  margin: 2rem 0 0.6rem;
}

h3 {
  font-family: var(--sans);
  font-size: 0.92rem;
  font-weight: bold;
  margin: 1.5rem 0 0.35rem;
}

h4 {
  font-family: var(--sans);
  font-size: 0.85rem;
  font-weight: bold;
  margin: 1.25rem 0 0.3rem;
}

p { margin-bottom: 0.85rem; }
a { color: var(--link); }
ul, ol { margin: 0 0 0.85rem 1.5rem; }
li { margin-bottom: 0.15rem; }
hr { border: none; border-top: 1px solid var(--border); margin: 1.5rem 0; }

code {
  font-family: var(--mono);
  font-size: 0.85em;
  background: var(--bg-code);
  border: 1px solid var(--border);
  padding: 0.05em 0.3em;
}

pre {
  font-family: var(--mono);
  font-size: 0.82rem;
  background: var(--bg-code);
  border: 1px solid var(--border);
  padding: 0.75rem 1rem;
  overflow-x: auto;
  margin: 0 0 1rem;
  line-height: 1.45;
}

pre code { background: none; border: none; padding: 0; }

.table-wrap { overflow-x: auto; margin-bottom: 1.25rem; }

table {
  border-collapse: collapse;
  font-family: var(--sans);
  font-size: 0.8rem;
  width: 100%;
}

th {
  background: #e8e8e8;
  border: 1px solid #999;
  padding: 0.3rem 0.6rem;
  text-align: center;
  font-weight: bold;
}

td {
  border: 1px solid #999;
  padding: 0.28rem 0.6rem;
  vertical-align: top;
}

.done    { font-family: var(--sans); font-size: 0.72rem; padding: 0.1em 0.4em; background: #d4edda; color: #155724; border: 1px solid #c3e6cb; }
.wip     { font-family: var(--sans); font-size: 0.72rem; padding: 0.1em 0.4em; background: #fff3cd; color: #856404; border: 1px solid #ffeeba; }
.planned { font-family: var(--sans); font-size: 0.72rem; padding: 0.1em 0.4em; background: #f8f8f8; color: #555;    border: 1px solid #ccc; }

.note {
  border-left: 3px solid #999;
  padding: 0.5rem 0.85rem;
  background: var(--bg-code);
  margin: 1rem 0;
  font-size: 0.88rem;
  font-family: var(--sans);
}

@media (max-width: 680px) {
  body { flex-direction: column; }
  #nav { width: 100%; height: auto; min-height: unset; position: static; border-right: none; border-bottom: 1px solid var(--border); }
  #content { padding: 1.25rem; }
}