:root {
  color-scheme: dark;
  --bg: #0a0e14;
  --bg-elevated: #0d1117;
  --panel: #151b23;
  --panel-2: #1c2430;
  --text: #c9d1d9;
  --muted: #8b949e;
  --line: #30363d;
  --purple: #8a2be2;
  --blue: #58a6ff;
  --green: #3fb950;
  --amber: #e5c07b;
  --white: #f0f6fc;
  --sidebar-w: 280px;
  --header-h: 56px;
  --content-max: 820px;
  --radius: 8px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.7 system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
a { color: var(--blue); text-decoration: none; }
a:hover { color: var(--white); text-decoration: underline; }
code, pre { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
.skip { position: absolute; left: -9999px; }
.skip:focus {
  left: 1rem; top: 1rem; z-index: 100;
  padding: .6rem 1rem; background: var(--white); color: var(--bg);
}

/* Top bar */
.topbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  gap: 1rem;
  height: var(--header-h);
  padding: 0 1.25rem;
  border-bottom: 1px solid var(--line);
  background: rgba(10, 14, 20, .92);
  backdrop-filter: blur(14px);
}
.topbar .wordmark {
  color: var(--white);
  font-weight: 750;
  font-size: .95rem;
  text-decoration: none;
  white-space: nowrap;
}
.topbar .wordmark:hover { text-decoration: none; color: var(--white); }
.topbar .tagline {
  color: var(--muted);
  font-size: .8rem;
  display: none;
}
.sidebar-toggle {
  display: none;
  padding: .45rem .7rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--panel);
  color: var(--text);
  font-size: .85rem;
  cursor: pointer;
}
.topbar-actions { margin-left: auto; display: flex; gap: .75rem; align-items: center; }
.topbar-actions a {
  color: var(--muted);
  font-size: .85rem;
  text-decoration: none;
}
.topbar-actions a:hover { color: var(--white); }
.topbar-actions .cta {
  padding: .4rem .75rem;
  border: 1px solid #388bfd;
  border-radius: 6px;
  background: #1f6feb;
  color: white !important;
  font-weight: 600;
}

/* Shell */
.shell {
  display: flex;
  min-height: 100vh;
  padding-top: var(--header-h);
}

/* Sidebar */
.sidebar {
  position: fixed;
  top: var(--header-h);
  left: 0;
  bottom: 0;
  width: var(--sidebar-w);
  overflow-y: auto;
  border-right: 1px solid var(--line);
  background: var(--bg-elevated);
  padding: 1.25rem 0 3rem;
}
.sidebar-inner { padding: 0 .75rem; }
.nav-group { margin-bottom: 1.5rem; }
.nav-group-title {
  margin: 0 0 .5rem .75rem;
  color: var(--muted);
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.sidebar nav a {
  display: block;
  padding: .4rem .75rem;
  border-radius: 6px;
  color: var(--muted);
  font-size: .88rem;
  text-decoration: none;
  line-height: 1.4;
}
.sidebar nav a:hover {
  color: var(--white);
  background: var(--panel);
  text-decoration: none;
}
.sidebar nav a.active {
  color: var(--white);
  background: var(--panel-2);
  font-weight: 600;
}

/* Main content */
.content {
  flex: 1;
  margin-left: var(--sidebar-w);
  min-width: 0;
}
.content-inner {
  max-width: calc(var(--content-max) + 4rem);
  margin: 0 auto;
  padding: 0 2rem 5rem;
}

/* Hero */
.hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: center;
  padding: 3.5rem 0 2.5rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 1rem;
}
.hero img {
  width: 100%;
  max-width: 420px;
  justify-self: end;
}
.kicker, .step {
  margin: 0 0 .5rem;
  color: var(--blue);
  font: 700 .72rem/1.2 ui-monospace, monospace;
  letter-spacing: .14em;
  text-transform: uppercase;
}
h1 {
  margin: 0 0 1rem;
  color: var(--white);
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  line-height: 1.08;
  letter-spacing: -.04em;
}
h2 {
  margin: 0 0 1rem;
  color: var(--white);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.2;
  letter-spacing: -.03em;
}
h3 {
  margin: 2rem 0 .75rem;
  color: var(--white);
  font-size: 1.15rem;
}
h4 {
  margin: 1.5rem 0 .5rem;
  color: var(--white);
  font-size: 1rem;
}
.topic {
  padding: 3rem 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: calc(var(--header-h) + 1rem);
}
.topic > p, .topic > ol, .topic > ul { max-width: var(--content-max); }
.lead { font-size: 1.1rem; color: var(--muted); max-width: 62ch; }

/* Cards & grids */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1px;
  margin: 1.75rem 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--line);
}
.card-grid article {
  display: flex;
  flex-direction: column;
  gap: .4rem;
  padding: 1.15rem;
  background: var(--panel);
}
.card-grid strong { color: var(--white); }
.card-grid span { color: var(--muted); font-size: .9rem; }
.benefits article { border-top: 2px solid var(--purple); }

.paths { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin: 1.5rem 0; }
.paths article {
  min-width: 0;
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
}
.paths article h3 { margin-top: 0; }
.paths pre { margin-bottom: 0; }

/* Timeline journey */
.journey {
  margin: 2rem 0;
  padding-left: 0;
  list-style: none;
  counter-reset: journey;
}
.journey > li {
  position: relative;
  margin: 0 0 1.75rem;
  padding: 0 0 0 3.25rem;
  counter-increment: journey;
}
.journey > li::before {
  content: counter(journey);
  position: absolute;
  left: 0; top: .15rem;
  width: 2.1rem; height: 2.1rem;
  display: grid; place-items: center;
  border-radius: 50%;
  background: linear-gradient(135deg, #1f6feb, var(--purple));
  color: white;
  font-weight: 800;
  font-size: .85rem;
}
.journey > li::after {
  content: "";
  position: absolute;
  left: 1rem; top: 2.5rem; bottom: -1rem;
  width: 2px;
  background: var(--line);
}
.journey > li:last-child::after { display: none; }
.journey strong { color: var(--white); display: block; margin-bottom: .35rem; }
.journey p { margin: 0 0 .5rem; color: var(--muted); }
.journey .you { color: #79c0ff; }
.journey .harness { color: #a371f7; }
.journey .agent { color: #56d364; }

/* Phase pills */
.phases {
  display: grid;
  gap: 1rem;
  margin: 1.75rem 0;
}
.phase {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem 1.25rem;
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
}
.phase-num {
  width: 2.5rem; height: 2.5rem;
  display: grid; place-items: center;
  border-radius: var(--radius);
  background: var(--panel-2);
  color: var(--blue);
  font-weight: 800;
  font-size: .9rem;
}
.phase h3 { margin: 0 0 .35rem; font-size: 1.05rem; }
.phase p { margin: 0; color: var(--muted); font-size: .92rem; }
.phase .who {
  margin-top: .6rem;
  font-size: .8rem;
  color: var(--muted);
}
.phase .who em { color: #79c0ff; font-style: normal; }
.phase .who strong { color: #a371f7; font-weight: 600; }

/* File format blocks */
.format-block {
  margin: 1.5rem 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.format-block header {
  position: static;
  display: block;
  padding: .75rem 1rem;
  border-bottom: 1px solid var(--line);
  background: var(--panel-2);
}
.format-block header strong { color: var(--white); }
.format-block header span { color: var(--muted); font-size: .85rem; margin-left: .5rem; }
.format-block pre { margin: 0; border: 0; border-radius: 0; border-left: 0; }

pre {
  margin: 1.25rem 0;
  overflow-x: auto;
  padding: 1.1rem 1.25rem;
  border: 1px solid var(--line);
  border-left: 3px solid var(--blue);
  border-radius: 6px;
  background: #06080c;
  color: #d6dae0;
  font-size: .82rem;
  line-height: 1.55;
}
:not(pre) > code {
  padding: .12rem .35rem;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--panel-2);
  color: #d6dae0;
  font-size: .88em;
}
.mermaid-wrap {
  margin: 1.5rem 0;
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  overflow: auto;
}
.mermaid-wrap pre.mermaid {
  margin: 0;
  border: 0;
  padding: 0;
  background: transparent;
  overflow: visible;
}
.mermaid-wrap svg {
  display: block;
  max-width: 100%;
  height: auto;
}

.output {
  display: flex;
  flex-wrap: wrap;
  gap: .65rem;
  align-items: center;
  margin: 1rem 0;
}
.output strong {
  color: var(--green);
  font-size: .75rem;
  letter-spacing: .1em;
  text-transform: uppercase;
}
.files, .note, .warning {
  max-width: var(--content-max);
  margin-top: 1.25rem;
  padding: 1rem 1.1rem;
  border-radius: 6px;
  background: var(--panel);
  color: var(--muted);
  font-size: .92rem;
}
.files strong { color: var(--blue); }
.warning { border-left: 3px solid var(--amber); }
.warning strong { color: var(--amber); }
.source {
  overflow-wrap: anywhere;
  padding: 1rem 1.1rem;
  border-left: 3px solid var(--purple);
  background: var(--panel);
  font-size: .92rem;
}
ol, ul { padding-left: 1.35rem; }
li { margin: .45rem 0; }

.checks { display: grid; gap: .7rem; margin-top: 1.5rem; }
.checks article {
  display: grid;
  grid-template-columns: 2.4rem 1fr;
  gap: 1rem;
  align-items: start;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--panel);
}
.checks article > span {
  display: grid; place-items: center;
  width: 2rem; height: 2rem;
  border-radius: 50%;
  background: var(--green);
  color: white;
  font-weight: 800;
}
.checks div { display: grid; gap: .35rem; min-width: 0; }
.checks strong { color: var(--white); }
.checks p { margin: 0; color: var(--muted); }

table {
  width: 100%;
  margin-top: 1.25rem;
  border-collapse: collapse;
  font-size: .92rem;
}
th, td {
  padding: .75rem .9rem;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}
th {
  color: var(--muted);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}
.compact-table td:first-child { width: 26%; }

.links {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--line);
}
.links a {
  display: flex;
  flex-direction: column;
  gap: .3rem;
  padding: 1.15rem;
  background: var(--panel);
  text-decoration: none;
}
.links strong { color: var(--white); }
.links span { color: var(--muted); font-size: .88rem; }

.site-footer {
  margin-left: var(--sidebar-w);
  display: flex;
  justify-content: space-between;
  gap: 2rem;
  padding: 2rem;
  border-top: 1px solid var(--line);
  background: #06080c;
  color: var(--muted);
  font-size: .9rem;
}
.site-footer p { margin: 0; font-family: Georgia, serif; font-style: italic; }

/* Responsive */
@media (min-width: 900px) {
  .topbar .tagline { display: inline; }
}
@media (max-width: 900px) {
  .sidebar-toggle { display: block; }
  .sidebar {
    transform: translateX(-100%);
    transition: transform .2s ease;
    z-index: 50;
  }
  .sidebar.open { transform: translateX(0); }
  .content { margin-left: 0; }
  .site-footer { margin-left: 0; }
  .hero { grid-template-columns: 1fr; padding-top: 2rem; }
  .hero img { justify-self: start; max-width: 320px; }
  .paths, .links { grid-template-columns: 1fr; }
  .card-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 520px) {
  .content-inner { padding: 0 1.1rem 4rem; }
  .card-grid { grid-template-columns: 1fr; }
  th, td { display: block; padding-inline: 0; }
  th { display: none; }
  td { border: 0; }
  td + td { padding-top: 0; border-bottom: 1px solid var(--line); color: var(--muted); }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }