:root {
  --bg: #07090f;
  --bg-2: #0c1220;
  --panel: #0f1729;
  --panel-2: #131c33;
  --border: #1c2a47;
  --border-bright: #2c4570;
  --text: #d6e4f0;
  --text-dim: #7b8db0;
  --text-faint: #4a5b80;
  --accent: #00e8ff;
  --accent-dim: #007a8c;
  --magenta: #ff3ed6;
  --green: #6cf09b;
  --yellow: #ffd066;
  --orange: #ff9c4a;
  --red: #ff5c7c;
  --purple: #b388ff;
  --wire: #1f3960;
  --wire-bright: #00e8ff;
  --font-mono: 'JetBrains Mono', 'Fira Code', ui-monospace, SFMono-Regular, Menlo, monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Inter, system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.5;
  overflow: hidden;
  -webkit-text-size-adjust: 100%;
}

body {
  display: grid;
  grid-template-columns: 280px 1fr;
  background:
    radial-gradient(ellipse at top left, rgba(0, 232, 255, 0.04), transparent 50%),
    radial-gradient(ellipse at bottom right, rgba(255, 62, 214, 0.03), transparent 50%),
    var(--bg);
}

/* ---------- sidebar ---------- */
.sidebar {
  background: linear-gradient(180deg, var(--panel) 0%, var(--bg-2) 100%);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-height: 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 20px 18px 16px;
  border-bottom: 1px solid var(--border);
}

.brand-text { flex: 1; min-width: 0; }

.brand-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-dim);
  width: 36px;
  height: 36px;
  border-radius: 6px;
  cursor: pointer;
  padding: 0;
  align-items: center;
  justify-content: center;
}

.brand-toggle .hamburger {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
}
.brand-toggle .hamburger::before,
.brand-toggle .hamburger::after {
  content: '';
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
}
.brand-toggle .hamburger::before { top: -5px; }
.brand-toggle .hamburger::after  { top:  5px; }

.logo {
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  border: 1px solid var(--border-bright);
  border-radius: 8px;
  color: var(--accent);
  background: rgba(0, 232, 255, 0.06);
  box-shadow: 0 0 12px rgba(0, 232, 255, 0.15);
  flex: 0 0 auto;
}

.brand h1 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.3px;
  color: #fff;
}

.tagline {
  margin: 2px 0 0;
  font-size: 11px;
  color: var(--text-faint);
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

#pattern-nav {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 12px 8px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-radius: 6px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-dim);
  text-align: left;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 13px;
  transition: background .15s, color .15s, border-color .15s;
}

.nav-item:hover {
  background: rgba(0, 232, 255, 0.04);
  color: var(--text);
}

.nav-item.active {
  background: rgba(0, 232, 255, 0.08);
  border-color: var(--border-bright);
  color: var(--accent);
}

.nav-item .nav-num {
  width: 22px;
  height: 22px;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-faint);
  border: 1px solid var(--border);
  border-radius: 4px;
  flex: 0 0 auto;
}

.nav-item.active .nav-num {
  color: var(--accent);
  border-color: var(--accent-dim);
}

.nav-home .nav-num {
  font-size: 13px;
}

.nav-separator {
  margin: 10px 4px 4px;
  padding: 0 10px;
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.9px;
  text-transform: uppercase;
  color: var(--text-faint);
  border-top: 1px solid var(--border);
  padding-top: 10px;
}

.nav-example .nav-num {
  font-size: 13px;
  color: var(--purple);
  border-color: rgba(179, 136, 255, 0.35);
}

.nav-example {
  color: var(--text-dim);
}

.nav-example:hover {
  background: rgba(179, 136, 255, 0.05);
  color: var(--text);
}

.nav-example.active {
  background: rgba(179, 136, 255, 0.1);
  border-color: rgba(179, 136, 255, 0.45);
  color: var(--purple);
}

.nav-example.active .nav-num {
  color: var(--purple);
  border-color: rgba(179, 136, 255, 0.5);
}

.side-footer {
  padding: 12px 14px 14px;
  border-top: 1px solid var(--border);
  color: var(--text-faint);
  font-size: 11px;
  font-family: var(--font-mono);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.lang-switcher {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 4px;
}

.lang-btn {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.6px;
  padding: 6px 0;
  background: transparent;
  color: var(--text-faint);
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s;
}

.lang-btn:hover {
  color: var(--text);
  border-color: var(--border-bright);
  background: rgba(0, 232, 255, 0.04);
}

.lang-btn.active {
  color: var(--accent);
  border-color: var(--accent-dim);
  background: rgba(0, 232, 255, 0.10);
}

/* ---------- viz ---------- */
.viz {
  display: grid;
  grid-template-rows: auto 1fr auto;
  overflow: hidden;
  min-width: 0;
  min-height: 0;
}

.viz-header {
  padding: 14px 32px 10px;
  border-bottom: 1px solid var(--border);
}

.viz-header h2 {
  margin: 0;
  font-size: 22px;
  color: #fff;
  font-weight: 600;
  letter-spacing: 0.3px;
}

.viz-header p {
  margin: 4px 0 0;
  color: var(--text-dim);
  font-size: 13px;
  max-width: 80ch;
}

#canvas-container {
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(rgba(28, 42, 71, 0.18) 1px, transparent 1px) 0 0 / 40px 40px,
    linear-gradient(90deg, rgba(28, 42, 71, 0.18) 1px, transparent 1px) 0 0 / 40px 40px,
    radial-gradient(ellipse at center, rgba(0, 232, 255, 0.025), transparent 70%),
    var(--bg);
  display: grid;
  place-items: center;
  min-height: 0;
}

#canvas {
  width: 100%;
  height: 100%;
  max-height: 100%;
  display: block;
}

.controls {
  position: absolute;
  top: 14px;
  right: 18px;
  display: flex;
  gap: 6px;
}

.controls button {
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 6px 11px;
  background: rgba(15, 23, 41, 0.85);
  color: var(--text-dim);
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s;
  backdrop-filter: blur(4px);
  min-height: 32px;
}

.controls button:hover {
  color: var(--accent);
  border-color: var(--border-bright);
  background: rgba(0, 232, 255, 0.05);
}

/* ---------- home panel (definitions on landing) ---------- */
.home-panel {
  width: 100%;
  max-width: 760px;
  padding: 28px 32px;
  overflow-y: auto;
  max-height: 100%;
}

.home-panel[hidden] { display: none; }

.home-intro {
  margin: 0 0 22px;
  font-size: 14px;
  color: var(--text);
  line-height: 1.6;
  padding: 14px 18px;
  border-left: 2px solid var(--accent-dim);
  background: rgba(0, 232, 255, 0.04);
  border-radius: 0 6px 6px 0;
}

.def-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.def {
  padding: 16px 18px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: rgba(15, 23, 41, 0.55);
}

.def h3 {
  margin: 0 0 8px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  color: var(--accent);
  font-family: var(--font-mono);
}

.def p {
  margin: 0;
  font-size: 13px;
  color: var(--text);
  line-height: 1.6;
}

.home-source {
  margin: 16px 0 0;
  font-size: 11px;
  color: var(--text-faint);
  font-family: var(--font-mono);
  letter-spacing: 0.3px;
}

.home-source a {
  color: var(--text-dim);
  text-decoration: none;
  border-bottom: 1px dotted var(--text-faint);
  transition: color .15s, border-color .15s;
}

.home-source a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent-dim);
}

.home-pick {
  margin: 18px 0 0;
  font-size: 13px;
  color: var(--text-dim);
  font-style: italic;
}

/* ---------- legend ---------- */
.viz-legend {
  padding: 12px 32px 16px;
  border-top: 1px solid var(--border);
  background: var(--bg-2);
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 24px;
  max-height: 22vh;
  overflow-y: auto;
}

.legend-block h3 {
  margin: 0 0 6px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.7px;
  text-transform: uppercase;
  color: var(--text-faint);
}

#pattern-steps {
  margin: 0;
  padding-left: 22px;
  font-size: 13px;
  color: var(--text);
  line-height: 1.65;
}

#pattern-steps li::marker {
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 11px;
}

#pattern-use {
  margin: 0;
  font-size: 13px;
  color: var(--text-dim);
  line-height: 1.6;
}

/* ---------- SVG nodes ---------- */
.node-bg {
  fill: var(--panel);
  stroke: var(--border-bright);
  stroke-width: 1.4;
  filter: url(#soft-glow);
  transition: stroke .25s, fill .25s;
}

.node text {
  fill: var(--text);
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 500;
  pointer-events: none;
}

.node .node-sub {
  font-family: var(--font-mono);
  font-size: 10px;
  fill: var(--text-faint);
  letter-spacing: 0.5px;
}

.node.active .node-bg {
  fill: rgba(0, 232, 255, 0.12);
  stroke: var(--accent);
  filter: drop-shadow(0 0 8px rgba(0, 232, 255, 0.55));
}

/* node type accents */
.node-user .node-bg,
.node-output .node-bg { stroke: var(--accent); }

.node-llm .node-bg { stroke: var(--magenta); }
.node-llm .node-sub { fill: var(--magenta); }

.node-tool .node-bg { stroke: var(--yellow); }
.node-tool .node-sub { fill: var(--yellow); }

.node-retriever .node-bg { stroke: var(--orange); }
.node-retriever .node-sub { fill: var(--orange); }

.node-db .node-bg { stroke: var(--green); }
.node-db .node-sub { fill: var(--green); }

.node-critic .node-bg { stroke: var(--red); }
.node-critic .node-sub { fill: var(--red); }

.node-planner .node-bg { stroke: var(--purple); }
.node-planner .node-sub { fill: var(--purple); }

.node-router .node-bg { stroke: var(--yellow); }
.node-router .node-sub { fill: var(--yellow); }

/* ---------- SVG wires ---------- */
.wire {
  stroke: var(--wire);
  stroke-width: 1.6;
  fill: none;
  stroke-linecap: round;
}

.wire-dim { stroke: #15243f; stroke-width: 1.2; stroke-dasharray: 4 4; }
.wire-feedback { stroke: #3a1e3f; stroke-dasharray: 5 4; }

/* packet */
.packet { pointer-events: none; }
.packet-dot { filter: url(#glow); }
.packet-label {
  fill: var(--text);
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.3px;
}

.wire-label {
  fill: var(--text-faint);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.4px;
}

.section-label {
  fill: var(--text-faint);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

/* ---------- responsive: tablet (≤ 1024px) ---------- */
@media (max-width: 1024px) {
  body { grid-template-columns: 240px 1fr; }
  .viz-header { padding: 16px 22px 12px; }
  .viz-header h2 { font-size: 19px; }
  .viz-legend { padding: 14px 22px 16px; gap: 20px; }
  .home-panel { padding: 22px 22px; }
}

/* ---------- responsive: mobile (≤ 768px) ---------- */
@media (max-width: 768px) {
  html, body { overflow: auto; height: auto; }
  body {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto;
    height: auto;
    min-height: 100vh;
  }

  .sidebar {
    border-right: none;
    border-bottom: 1px solid var(--border);
    overflow: visible;
    position: sticky;
    top: 0;
    z-index: 20;
    background: var(--panel);
  }

  .brand {
    padding: 12px 14px;
    gap: 10px;
  }

  .logo { width: 34px; height: 34px; }
  .logo svg { width: 22px; height: 22px; }

  .brand h1 { font-size: 14px; }
  .tagline { font-size: 10px; letter-spacing: 0.3px; }

  .brand-toggle { display: inline-flex; flex: 0 0 auto; }

  /* nav collapse on mobile */
  .sidebar.nav-collapsed #pattern-nav,
  .sidebar.nav-collapsed .side-footer { display: none; }

  #pattern-nav {
    flex-direction: column;
    max-height: 50vh;
    padding: 8px 10px;
    border-top: 1px solid var(--border);
  }

  .nav-item {
    padding: 11px 12px;
    font-size: 13.5px;
    min-height: 44px;
  }

  .side-footer {
    padding: 10px 14px 12px;
    flex-direction: row;
    align-items: center;
    gap: 12px;
    border-top: 1px solid var(--border);
    flex-wrap: wrap;
  }

  .lang-switcher {
    flex: 0 0 auto;
    grid-template-columns: repeat(4, auto);
    gap: 6px;
  }

  .lang-btn {
    padding: 7px 12px;
    min-width: 44px;
    min-height: 32px;
  }

  #footer-text {
    flex: 1;
    min-width: 0;
    font-size: 10px;
    text-align: right;
  }

  /* main */
  .viz {
    grid-template-rows: auto auto auto;
    overflow: visible;
  }

  .viz-header {
    padding: 14px 16px 10px;
  }
  .viz-header h2 { font-size: 17px; }
  .viz-header p { font-size: 12.5px; line-height: 1.5; }

  #canvas-container {
    min-height: 320px;
    aspect-ratio: 5 / 3;
    overflow-x: auto;
    overflow-y: hidden;
    place-items: center;
  }

  #canvas {
    min-width: 600px;
    height: 100%;
  }

  .controls {
    top: 8px;
    right: 8px;
    gap: 4px;
  }
  .controls button {
    padding: 6px 9px;
    font-size: 10.5px;
  }

  /* home panel on mobile: stack defs, allow scroll */
  .home-panel {
    padding: 18px 16px 24px;
    max-height: none;
    overflow-y: visible;
    aspect-ratio: auto;
  }

  /* on mobile, the home panel breaks out of the aspect-ratio container */
  #canvas-container:has(.home-panel:not([hidden])) {
    aspect-ratio: auto;
    min-height: 0;
    overflow: visible;
  }

  .home-intro {
    font-size: 13.5px;
    padding: 12px 14px;
  }

  .def-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .def { padding: 14px 16px; }
  .def p { font-size: 13px; }

  .viz-legend {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 14px 16px 20px;
    max-height: none;
  }
}

/* ---------- small phones (≤ 380px) ---------- */
@media (max-width: 380px) {
  .brand { padding: 10px 12px; gap: 8px; }
  .lang-btn { padding: 6px 10px; min-width: 40px; }
  #footer-text { display: none; }
  .viz-header { padding: 12px 14px 8px; }
  .home-panel { padding: 14px 14px 20px; }
  #canvas-container { min-height: 260px; }
  #canvas { min-width: 540px; }
}