@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

/* ==========================================================================
   HPC & AI Infra Technical Publication Design System
   Inspired by Anthropic Claude Research, Stripe Press & Linear.app Aesthetics
   Refined typography, warm ivory palette, macOS code blocks, and crisp diagrams
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. Root Variables & Theme Tokens
   -------------------------------------------------------------------------- */
:root {
  /* Brand Accent Tokens */
  --primary-accent: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --terracotta: #cc6644;
  --terracotta-hover: #b35536;
  --terracotta-light: #fbf5f2;
  
  /* Neutral Palette (Warm Anthropic Light) */
  --bg-main: #fafaf7;
  --bg-surface: #ffffff;
  --bg-subtle: #f4f3ef;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --text-strong: #0f172a;
  --border-light: rgba(15, 23, 42, 0.08);
  --border-focus: rgba(37, 99, 235, 0.4);

  /* Elevation Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04), 0 1px 2px rgba(0, 0, 0, 0.02);
  --shadow-md: 0 4px 14px -2px rgba(15, 23, 42, 0.06), 0 2px 6px -1px rgba(15, 23, 42, 0.03);
  --shadow-lg: 0 12px 30px -4px rgba(15, 23, 42, 0.08), 0 4px 12px -2px rgba(15, 23, 42, 0.04);
  --card-radius: 12px;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Inter", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", "Fira Code", Menlo, Monaco, Consolas, monospace;
}

/* Dark Mode Tokens (Deep Space Slate) */
body.quarto-dark {
  --bg-main: #0d1117;
  --bg-surface: #161b22;
  --bg-subtle: #1f242c;
  --text-main: #e2e8f0;
  --text-muted: #94a3b8;
  --text-strong: #f8fafc;
  --border-light: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(96, 165, 250, 0.4);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 12px 36px rgba(0, 0, 0, 0.55);
}

/* --------------------------------------------------------------------------
   2. Global Canvas & Typography
   -------------------------------------------------------------------------- */
html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.78;
  letter-spacing: -0.012em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* Optimal Prose Measure on Large Displays */
main.content {
  max-width: 820px;
  margin-left: auto;
  margin-right: auto;
  padding-top: 1.5rem;
  padding-bottom: 4rem;
}

/* Headings Hierarchy */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-strong);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-top: 2.2rem;
  margin-bottom: 0.75rem;
  line-height: 1.35;
}

h1.title {
  font-size: 2.45rem;
  font-weight: 850;
  letter-spacing: -0.035em;
  line-height: 1.2;
  margin-bottom: 0.45rem;
  background: linear-gradient(135deg, #0f172a 0%, #1e3a8a 55%, #2563eb 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

body.quarto-dark h1.title {
  background: linear-gradient(135deg, #f8fafc 0%, #93c5fd 55%, #60a5fa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

p.subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  font-weight: 500;
  margin-bottom: 1.8rem;
  line-height: 1.5;
}

h2 {
  font-size: 1.58rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border-light);
  margin-top: 2.5rem;
}

h3 {
  font-size: 1.26rem;
  margin-top: 1.8rem;
}

h4 {
  font-size: 1.08rem;
  font-weight: 650;
}

p {
  margin-bottom: 1.25rem;
}

a {
  color: var(--primary-accent);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.15s ease-in-out;
}

a:hover {
  color: var(--primary-hover);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* --------------------------------------------------------------------------
   3. Frosted Glass Navbar & Modern Sidebar
   -------------------------------------------------------------------------- */
.navbar {
  backdrop-filter: blur(16px) !important;
  -webkit-backdrop-filter: blur(16px) !important;
  background-color: #0f172a !important;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12) !important;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.18) !important;
  transition: background-color 0.3s ease;
  z-index: 1030 !important;
}

body.quarto-dark .navbar {
  background-color: #0a0e17 !important;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08) !important;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.5) !important;
}

.navbar .navbar-brand,
.navbar-brand span {
  color: #ffffff !important;
  font-weight: 750 !important;
  letter-spacing: -0.02em;
}

.navbar .nav-link,
.navbar-nav .nav-link {
  color: rgba(241, 245, 249, 0.92) !important;
  font-weight: 550 !important;
  font-size: 0.93rem !important;
  padding: 0.5rem 0.85rem !important;
  transition: color 0.15s ease, background-color 0.15s ease !important;
}

.navbar .nav-link:hover,
.navbar-nav .nav-link:hover,
.navbar .nav-link:focus,
.navbar-nav .nav-link:focus {
  color: #38bdf8 !important;
}

.navbar-nav .dropdown-menu {
  background-color: #0f172a !important;
  border: 1px solid rgba(255, 255, 255, 0.15) !important;
  border-radius: 10px !important;
  box-shadow: 0 12px 36px rgba(0, 0, 0, 0.45) !important;
  padding: 0.5rem 0.4rem !important;
}

.navbar-nav .dropdown-item {
  color: #e2e8f0 !important;
  font-weight: 500 !important;
  border-radius: 6px !important;
  padding: 0.45rem 0.85rem !important;
  font-size: 0.9rem !important;
  transition: all 0.15s ease !important;
}

.navbar-nav .dropdown-item:hover {
  background-color: rgba(56, 189, 248, 0.15) !important;
  color: #38bdf8 !important;
}

.navbar-nav .dropdown-divider {
  border-top-color: rgba(255, 255, 255, 0.12) !important;
}

.navbar .navbar-toggler {
  border-color: rgba(255, 255, 255, 0.25) !important;
}

.navbar .navbar-toggler-icon {
  filter: invert(1) brightness(1.5) !important;
}

#quarto-search .aa-DetachedSearchButton,
.navbar #quarto-search .aa-Autocomplete {
  color: #ffffff !important;
}

.sidebar nav[role="doc-toc"] {
  border-left: 1px solid var(--border-light);
  padding-left: 0.85rem;
}

.sidebar nav[role="doc-toc"] ul > li > a {
  color: var(--text-muted);
  font-size: 0.88rem;
  padding: 0.3rem 0;
  display: block;
  transition: all 0.15s ease;
}

.sidebar nav[role="doc-toc"] ul > li > a:hover {
  color: var(--text-strong);
}

.sidebar nav[role="doc-toc"] ul > li > a.active {
  color: var(--primary-accent) !important;
  font-weight: 650;
  position: relative;
}

/* --------------------------------------------------------------------------
   4. Anthropic / Linear Style Callouts
   -------------------------------------------------------------------------- */
.callout {
  border-radius: var(--card-radius) !important;
  border-left-width: 4px !important;
  border-top-width: 1px !important;
  border-right-width: 1px !important;
  border-bottom-width: 1px !important;
  box-shadow: var(--shadow-sm);
  margin: 1.8rem 0;
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.2s ease;
}

.callout:hover {
  transform: translateY(-1.5px);
  box-shadow: var(--shadow-md);
}

.callout-header {
  font-weight: 650;
  font-size: 0.98rem;
  letter-spacing: -0.01em;
  padding: 0.75rem 1rem;
}

.callout-body {
  font-size: 0.94rem;
  line-height: 1.72;
  padding: 0.5rem 1rem 1rem 1rem;
}

/* Callout Note (Deep Azure) */
.callout-note {
  background-color: #f8fbff !important;
  border-color: #bfdbfe !important;
  border-left-color: #2563eb !important;
}

body.quarto-dark .callout-note {
  background-color: #121e33 !important;
  border-color: #1e3a8a !important;
  border-left-color: #60a5fa !important;
}

/* Callout Tip (Terracotta / Emerald) */
.callout-tip {
  background-color: #fbf8f5 !important;
  border-color: #fed7aa !important;
  border-left-color: var(--terracotta) !important;
}

body.quarto-dark .callout-tip {
  background-color: #251d18 !important;
  border-color: #7c2d12 !important;
  border-left-color: #fb923c !important;
}

/* Callout Important (Golden Amber) */
.callout-important {
  background-color: #fffdf5 !important;
  border-color: #fde68a !important;
  border-left-color: #d97706 !important;
}

body.quarto-dark .callout-important {
  background-color: #241f12 !important;
  border-color: #78350f !important;
  border-left-color: #fcd34d !important;
}

/* Callout Warning */
.callout-warning {
  background-color: #fff8f6 !important;
  border-color: #fecdd3 !important;
  border-left-color: #e11d48 !important;
}

body.quarto-dark .callout-warning {
  background-color: #26141a !important;
  border-color: #881337 !important;
  border-left-color: #fb7185 !important;
}

/* --------------------------------------------------------------------------
   5. macOS Style Code Blocks & Terminal Windows
   -------------------------------------------------------------------------- */
pre, code {
  font-family: var(--font-mono) !important;
}

div.sourceCode {
  position: relative;
  background-color: #f8fafc;
  border-radius: 12px !important;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
  margin: 1.6rem 0;
  overflow: hidden;
}

body.quarto-dark div.sourceCode {
  background-color: #161b22;
  border-color: var(--border-light);
  box-shadow: var(--shadow-md);
}

/* macOS Terminal Top Dots */
div.sourceCode::before {
  content: "";
  display: block;
  height: 28px;
  background-color: #f1f5f9;
  border-bottom: 1px solid var(--border-light);
  background-image: radial-gradient(circle, #ff5f56 5px, transparent 6px),
                    radial-gradient(circle, #ffbd2e 5px, transparent 6px),
                    radial-gradient(circle, #27c93f 5px, transparent 6px);
  background-size: 16px 16px;
  background-position: 12px center, 32px center, 52px center;
  background-repeat: no-repeat;
}

body.quarto-dark div.sourceCode::before {
  background-color: #1f242c;
  border-bottom-color: var(--border-light);
}

div.sourceCode pre {
  padding: 1rem 1.25rem !important;
  margin: 0 !important;
  background: transparent !important;
}

code:not(pre code) {
  padding: 0.18rem 0.45rem;
  border-radius: 6px;
  font-size: 0.88em;
  background-color: #f1f5f9;
  color: #0f172a;
  border: 1px solid #e2e8f0;
  font-weight: 500;
}

body.quarto-dark code:not(pre code) {
  background-color: #1f242c;
  color: #38bdf8;
  border-color: #334155;
}

/* Floating Code Copy Button */
.code-copy-button {
  top: 6px !important;
  right: 10px !important;
  border-radius: 6px !important;
  opacity: 0.7;
  transition: opacity 0.2s ease, transform 0.15s ease;
}

.code-copy-button:hover {
  opacity: 1;
  transform: scale(1.05);
}

/* --------------------------------------------------------------------------
   6. Editorial Grade Minimalist Tables
   -------------------------------------------------------------------------- */
.table-responsive,
div.quarto-table {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 1.8rem 0;
}

table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  border: 1px solid var(--border-light);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  font-size: 0.94rem;
}

thead th {
  background-color: #f8fafc;
  color: var(--text-strong);
  font-weight: 650;
  padding: 0.85rem 1rem;
  border-bottom: 2px solid #e2e8f0;
  text-align: left;
  letter-spacing: -0.01em;
}

body.quarto-dark thead th {
  background-color: #1e242d;
  color: #f8fafc;
  border-bottom-color: #334155;
}

tbody td {
  padding: 0.8rem 1rem;
  border-bottom: 1px solid #f1f5f9;
  font-variant-numeric: tabular-nums;
}

body.quarto-dark tbody td {
  border-bottom-color: #1f242c;
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background-color: rgba(37, 99, 235, 0.02);
}

body.quarto-dark tbody tr:hover {
  background-color: rgba(96, 165, 250, 0.04);
}

/* --------------------------------------------------------------------------
   7. Figure Cards & Image Framing
   -------------------------------------------------------------------------- */
.figure, figure, img {
  border-radius: 10px;
  max-width: 100%;
  height: auto;
}

.img-card {
  background: var(--bg-surface);
  padding: 1rem;
  border-radius: 14px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-light);
  margin: 2.2rem auto;
  text-align: center;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.img-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.img-card img {
  border-radius: 8px;
  display: block;
  margin: 0 auto;
}

.figure-caption, figcaption, p.caption {
  font-size: 0.88rem;
  color: var(--text-muted);
  text-align: center;
  margin-top: 0.75rem;
  margin-bottom: 1.5rem;
  font-weight: 500;
  display: block;
}

/* --------------------------------------------------------------------------
   8. HTML Flow & Sequence Diagrams (scripts/mermaid_to_html.py)
   Boxes size themselves from their text and wrap; nothing is clipped.
   -------------------------------------------------------------------------- */
.fd {
  --fd-bg: #faf9f5;
  --fd-fg: #262626;
  --fd-muted: #6b6259;
  --fd-node-bg: #ffffff;
  --fd-node-border: #d6cbc2;
  --fd-accent: #cc6644;
  --fd-dec-bg: #fff7ed;
  --fd-dec-border: #e3a46f;
  --fd-db-bg: #f1f5f9;
  --fd-db-border: #94a3b8;
  --fd-sg-bg: rgba(204, 102, 68, 0.045);
  --fd-sg-border: rgba(204, 102, 68, 0.38);
  --fd-sg2-bg: rgba(37, 99, 235, 0.04);
  --fd-sg2-border: rgba(37, 99, 235, 0.32);
  --fd-edge: #8c5e45;
  --fd-label-bg: #fffdf9;
  --fd-label-border: #e7d9cc;
  --fd-note-bg: #fbf5f2;
  position: relative;
  isolation: isolate;
  margin: 1.6rem 0 0.4rem;
  padding: 22px 18px;
  background: var(--fd-bg);
  border: 1px solid var(--border-light);
  border-radius: 14px;
  box-shadow: var(--shadow-sm);
  color: var(--fd-fg);
  font-family: var(--font-sans);
  overflow-x: auto;
  overflow-y: hidden;
}

body.quarto-dark .fd {
  --fd-bg: #151b22;
  --fd-fg: #e5e7eb;
  --fd-muted: #9ca3af;
  --fd-node-bg: #1f2630;
  --fd-node-border: #3b4553;
  --fd-accent: #e08a6a;
  --fd-dec-bg: #2a2019;
  --fd-dec-border: #b4774a;
  --fd-db-bg: #1b2430;
  --fd-db-border: #5b6b80;
  --fd-sg-bg: rgba(224, 138, 106, 0.06);
  --fd-sg-border: rgba(224, 138, 106, 0.42);
  --fd-sg2-bg: rgba(96, 165, 250, 0.06);
  --fd-sg2-border: rgba(96, 165, 250, 0.38);
  --fd-edge: #c98b70;
  --fd-label-bg: #1b2129;
  --fd-label-border: #3b4553;
  --fd-note-bg: #241d19;
}

.fd + p.caption { margin-top: 0.6rem; }

/* ---- flowchart layout ---- */
.fd-stack { display: flex; flex-direction: column; align-items: center; gap: 26px; min-width: 0; }
.fd-comp { display: flex; align-items: center; justify-content: center; max-width: 100%; min-width: 0; }
.fd-comp.fd-lr { flex-direction: row; }
.fd-comp.fd-td,
.fd-comp.fd-lr.fd-vert { flex-direction: column; }
.fd-rank { display: flex; align-items: center; justify-content: center; gap: 14px 18px; min-width: 0; }
.fd-lr > .fd-rank { flex-direction: column; flex: 0 1 auto; }
.fd-td > .fd-rank,
.fd-lr.fd-vert > .fd-rank { flex-direction: row; flex-wrap: wrap; max-width: 100%; }
/* up to four siblings stay on one row (boxes narrow, text wraps) so arrows never cross a box */
.fd-td > .fd-rank.fd-few,
.fd-lr.fd-vert > .fd-rank.fd-few { flex-wrap: nowrap; gap: 10px; }
.fd-td > .fd-rank.fd-few > .fd-node,
.fd-lr.fd-vert > .fd-rank.fd-few > .fd-node { flex: 0 1 auto; min-width: 0; }
.fd-td > .fd-rank.fd-few > .fd-sg,
.fd-lr.fd-vert > .fd-rank.fd-few > .fd-sg { flex: 0 1 auto; }
.fd-gap { flex: none; }
.fd-lr > .fd-gap { width: calc(var(--gl, 48px) + var(--grow, 0px)); height: 1px; }
.fd-td > .fd-gap,
.fd-lr.fd-vert > .fd-gap { height: calc(var(--gt, 40px) + var(--grow, 0px)); width: 1px; }
/* without JS there are no arrows: keep the reading order obvious */
.fd-flow:not(.fd-js) .fd-lr > .fd-gap::after { content: "→"; color: var(--fd-edge); }
.fd-flow:not(.fd-js) .fd-td > .fd-gap::after { content: "↓"; color: var(--fd-edge); }

.fd-node {
  position: relative;
  z-index: 2;
  box-sizing: border-box;
  min-width: 88px;
  max-width: 250px;
  padding: 8px 13px;
  background: var(--fd-node-bg);
  border: 1.5px solid var(--fd-node-border);
  border-radius: 9px;
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.05);
  font-size: 13.5px;
  line-height: 1.5;
  text-align: center;
  overflow-wrap: anywhere;
  word-break: normal;
}
.fd-lr:not(.fd-vert) > .fd-rank > .fd-node { width: 100%; }
.fd-node code, .fd-label code, .sd-grid code { font-size: 0.92em; white-space: normal; }
.fd-node.fd-dec { background: var(--fd-dec-bg); border-color: var(--fd-dec-border); border-radius: 16px; font-weight: 550; }
.fd-node.fd-round { border-radius: 999px; padding: 8px 18px; }
.fd-node.fd-soft { border-radius: 14px; }
.fd-node.fd-db { background: var(--fd-db-bg); border-color: var(--fd-db-border); border-radius: 14px / 22px; }
.fd-node.fd-hex, .fd-node.fd-sub { border-style: double; border-width: 3px; }
.fd-node.fd-io { border-left-width: 4px; border-right-width: 4px; }

.fd-sg {
  position: relative;
  box-sizing: border-box;
  max-width: 100%;
  min-width: 0;
  padding: 10px 14px 16px;
  background: var(--fd-sg-bg);
  border: 1.5px dashed var(--fd-sg-border);
  border-radius: 13px;
}
.fd-sg[data-depth="1"], .fd-sg[data-depth="3"] { background: var(--fd-sg2-bg); border-color: var(--fd-sg2-border); }
.fd-sg-title {
  position: relative;
  z-index: 2;
  margin: 0 0 12px;
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--fd-accent);
  text-align: center;
  overflow-wrap: anywhere;
}
.fd-sg[data-depth="1"] > .fd-sg-title, .fd-sg[data-depth="3"] > .fd-sg-title { color: var(--primary-accent); }
.fd-lr:not(.fd-vert) > .fd-rank > .fd-sg { width: 100%; }

.fd-e { display: none; }
.fd-dummy { flex: none; width: 14px; height: 14px; visibility: hidden; }
.fd-svg { position: absolute; left: 0; top: 0; z-index: 1; pointer-events: none; overflow: visible; }
.fd-edge { fill: none; stroke: var(--fd-edge); stroke-width: 1.6; opacity: 0.9; }
.fd-edge-dash { stroke-dasharray: 5 4; }
.fd-edge-thick { stroke-width: 3; }
.fd-head { fill: var(--fd-edge); }
.fd-labels { position: absolute; left: 0; top: 0; z-index: 3; width: 0; height: 0; }
.fd-label {
  position: absolute;
  box-sizing: border-box;
  width: max-content;
  max-width: 190px;
  padding: 2px 8px;
  background: var(--fd-label-bg);
  border: 1px solid var(--fd-label-border);
  border-radius: 6px;
  font-size: 12px;
  line-height: 1.4;
  color: var(--fd-muted);
  text-align: center;
  overflow-wrap: anywhere;
}
.fd-label-tight { opacity: 0.96; box-shadow: 0 1px 4px rgba(0, 0, 0, 0.12); }

/* ---- sequence diagrams ---- */
.sd-grid {
  display: grid;
  grid-template-columns: repeat(var(--n), minmax(118px, 1fr));
  column-gap: 0;
  row-gap: 6px;
  min-width: calc(var(--n) * 118px);
  font-size: 13px;
  line-height: 1.45;
}
.sd-life {
  justify-self: center;
  width: 0;
  border-left: 1.5px dashed var(--fd-node-border);
  z-index: 0;
}
.sd-actor {
  z-index: 1;
  justify-self: center;
  align-self: end;
  box-sizing: border-box;
  max-width: calc(100% - 10px);
  margin-bottom: 8px;
  padding: 8px 10px;
  background: var(--fd-node-bg);
  border: 1.5px solid var(--fd-accent);
  border-radius: 9px;
  font-weight: 650;
  font-size: 13px;
  text-align: center;
  overflow-wrap: break-word;
}
.sd-msg { z-index: 1; position: relative; padding: 2px 0 4px; min-width: 0; }
.sd-text {
  margin: 0 calc(50% / var(--k));
  padding: 0 8px;
  text-align: center;
  overflow-wrap: break-word;
}
.sd-num {
  display: inline-block;
  min-width: 18px;
  height: 18px;
  margin-right: 6px;
  padding: 0 4px;
  border-radius: 9px;
  background: var(--fd-accent);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  line-height: 18px;
  text-align: center;
  vertical-align: 1px;
}
.sd-line { position: relative; height: 0; margin: 4px calc(50% / var(--k)) 0; border-top: 1.6px solid var(--fd-edge); }
.sd-dash .sd-line { border-top-style: dashed; }
.sd-line::after {
  content: "";
  position: absolute;
  top: -5.6px;
  border-top: 5px solid transparent;
  border-bottom: 5px solid transparent;
}
.sd-r .sd-line::after { right: -1px; border-left: 9px solid var(--fd-edge); }
.sd-l .sd-line::after { left: -1px; border-right: 9px solid var(--fd-edge); }
.sd-h-open .sd-line::after { display: none; }
.sd-self .sd-text { margin-right: 0; margin-left: calc(50% / var(--k)); text-align: left; padding-left: 26px; }
.sd-self .sd-loop {
  position: absolute;
  left: calc(50% / var(--k));
  top: 3px;
  width: 18px;
  bottom: 6px;
  border: 1.6px solid var(--fd-edge);
  border-left: none;
  border-radius: 0 8px 8px 0;
}
.sd-self.sd-dash .sd-loop { border-style: dashed; border-left: none; }
.sd-note {
  z-index: 1;
  box-sizing: border-box;
  margin: 3px 6px;
  padding: 6px 10px;
  background: var(--fd-note-bg);
  border: 1px solid var(--fd-sg-border);
  border-radius: 8px;
  font-size: 12.5px;
  color: var(--fd-fg);
  text-align: center;
  overflow-wrap: anywhere;
}
.sd-note-right { margin-left: calc(50% / var(--k) + 8px); }
.sd-note-left { margin-right: calc(50% / var(--k) + 8px); }
.sd-frame, .sd-frame-else {
  z-index: 1;
  margin-top: 4px;
  padding: 3px 8px;
  border-top: 1.5px solid var(--fd-sg-border);
  font-size: 12.5px;
  color: var(--fd-muted);
  overflow-wrap: anywhere;
}
.sd-frame-else { border-top-style: dashed; }
.sd-kw {
  display: inline-block;
  margin-right: 8px;
  padding: 0 6px;
  border-radius: 4px;
  background: var(--fd-sg-border);
  color: #fff;
  font-weight: 700;
  font-size: 11px;
}
.sd-frame-end { z-index: 1; border-top: 1.5px solid var(--fd-sg-border); height: 0; }

@media (max-width: 576px) {
  .fd { padding: 16px 8px; }
  .fd-node { font-size: 13px; padding: 7px 10px; }
  .fd-label { max-width: 150px; font-size: 11.5px; }
  .sd-grid { grid-template-columns: repeat(var(--n), minmax(92px, 1fr)); min-width: calc(var(--n) * 92px); font-size: 12.5px; }
  .sd-actor { padding: 6px 6px; font-size: 12px; }
  .sd-text { padding: 0 4px; }
}

/* --------------------------------------------------------------------------
   9. Native MathML Typography
   -------------------------------------------------------------------------- */
math {
  font-family: "STIX Two Math", "Cambria Math", "Latin Modern Math", KaTeX_Math, "Times New Roman", Times, serif;
  font-size: 1.05em;
  letter-spacing: normal;
  text-rendering: optimizeLegibility;
}

math[display="block"] {
  display: block;
  margin: 1.5rem auto;
  text-align: center;
  overflow-x: auto;
  overflow-y: hidden;
  max-width: 100%;
  padding: 0.6rem 0.2rem;
  scrollbar-width: thin;
}

body.quarto-dark math {
  color: #f1f5f9;
}

/* --------------------------------------------------------------------------
   10. Custom Sleek Scrollbars
   -------------------------------------------------------------------------- */
::-webkit-scrollbar {
  width: 7px;
  height: 7px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: rgba(148, 163, 184, 0.4);
  border-radius: 9999px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(100, 116, 139, 0.7);
}

/* ==========================================================================
   Course Pagination Cards (Previous & Next Lesson Navigation)
   ========================================================================== */
.course-pagination {
  display: flex !important;
  justify-content: space-between !important;
  align-items: stretch !important;
  gap: 1.25rem !important;
  margin: 3.5rem 0 2rem 0 !important;
  padding-top: 2rem !important;
  border-top: 1px solid var(--border-light) !important;
}

.pagination-link {
  flex: 1 1 48% !important;
  display: block !important;
  padding: 1.15rem 1.45rem !important;
  border-radius: var(--card-radius) !important;
  background-color: var(--bg-surface) !important;
  border: 1px solid var(--border-light) !important;
  box-shadow: var(--shadow-sm) !important;
  text-decoration: none !important;
  color: var(--text-main) !important;
  font-size: 0.96rem !important;
  font-weight: 550 !important;
  line-height: 1.5 !important;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s ease, border-color 0.2s ease !important;
}

.pagination-link strong {
  display: block !important;
  font-size: 0.82rem !important;
  font-weight: 700 !important;
  letter-spacing: 0.04em !important;
  color: var(--text-muted) !important;
  margin-bottom: 0.35rem !important;
  transition: color 0.2s ease !important;
}

.pagination-prev {
  text-align: left !important;
}

.pagination-next {
  text-align: right !important;
  margin-left: auto !important;
}

.pagination-link:hover {
  transform: translateY(-2.5px) !important;
  box-shadow: var(--shadow-md) !important;
  border-color: var(--primary-accent) !important;
  color: var(--primary-accent) !important;
}

.pagination-link:hover strong {
  color: var(--primary-accent) !important;
}

body.quarto-dark .pagination-link {
  background-color: var(--bg-surface) !important;
  border-color: var(--border-light) !important;
}

body.quarto-dark .pagination-link:hover {
  border-color: #60a5fa !important;
  color: #60a5fa !important;
}

body.quarto-dark .pagination-link:hover strong {
  color: #60a5fa !important;
}

/* Native Quarto Page Navigation Footer Enhancement */
.page-navigation {
  margin-top: 2rem !important;
  padding-top: 1rem !important;
}

.page-navigation .nav-page {
  font-weight: 600 !important;
}

@media (max-width: 640px) {
  .course-pagination {
    flex-direction: column !important;
    gap: 0.85rem !important;
  }
  .pagination-link {
    width: 100% !important;
    text-align: center !important;
  }
}


/* ==========================================================================
   Anthropic / Stripe Style Interactive Learning Roadmap Component
   ========================================================================== */
.learning-roadmap {
  margin: 2.2rem 0 3rem 0;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.roadmap-stage {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 14px;
  padding: 1.4rem 1.6rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.2s ease;
}

.roadmap-stage:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: rgba(37, 99, 235, 0.3);
}

body.quarto-dark .roadmap-stage {
  background: var(--bg-surface);
  border-color: var(--border-light);
}

body.quarto-dark .roadmap-stage:hover {
  border-color: rgba(96, 165, 250, 0.4);
}

.stage-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #cc6644;
  background: #fbf5f2;
  padding: 0.28rem 0.75rem;
  border-radius: 9999px;
  margin-bottom: 0.75rem;
  border: 1px solid rgba(204, 102, 68, 0.25);
}

body.quarto-dark .stage-badge {
  background: rgba(217, 119, 87, 0.15);
  color: #f09a7d;
  border-color: rgba(217, 119, 87, 0.3);
}

.stage-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-strong);
  margin-bottom: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.stage-courses {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  align-items: center;
}

.course-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: 9px;
  padding: 0.55rem 0.95rem;
  text-decoration: none !important;
  color: var(--text-main) !important;
  font-size: 0.92rem;
  font-weight: 600;
  transition: all 0.2s ease;
}

.course-chip:hover {
  border-color: var(--primary-accent);
  color: var(--primary-accent) !important;
  background: #eff6ff;
  transform: translateY(-1.5px);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.12);
}

body.quarto-dark .course-chip:hover {
  border-color: #38bdf8;
  color: #38bdf8 !important;
  background: rgba(56, 189, 248, 0.12);
}

.course-chip .chip-num {
  background: rgba(0, 0, 0, 0.06);
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 750;
  padding: 0.12rem 0.4rem;
  border-radius: 5px;
}

body.quarto-dark .course-chip .chip-num {
  background: rgba(255, 255, 255, 0.1);
  color: #94a3b8;
}

.stage-arrow {
  color: #94a3b8;
  font-weight: 700;
  font-size: 0.85rem;
  margin: 0 0.1rem;
}

.stage-desc {
  margin-top: 0.85rem;
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.62;
}

.stage-connector {
  display: flex;
  justify-content: center;
  align-items: center;
  margin: -0.4rem 0;
  color: #cc6644;
  font-size: 1.25rem;
  font-weight: 800;
}

/* --------------------------------------------------------------------------
   Interview roadmap (interview/index.qmd): four stage cards, no runtime JS
   -------------------------------------------------------------------------- */
.rm-roadmap {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
  margin: 1.6rem 0 0.8rem;
  counter-reset: none;
}
.rm-stage {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px 14px 14px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-top: 3px solid var(--rm-c, var(--terracotta));
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
  min-width: 0;
}
.rm-stage[data-step="2"] { --rm-c: #2563eb; }
.rm-stage[data-step="3"] { --rm-c: #7c3aed; }
.rm-stage[data-step="4"] { --rm-c: #0f766e; }
.rm-stage:not(:last-child)::after {
  content: "";
  position: absolute;
  top: 50%;
  right: -21px;
  width: 14px;
  height: 14px;
  border-top: 2px solid var(--text-muted);
  border-right: 2px solid var(--text-muted);
  transform: translateY(-50%) rotate(45deg);
  opacity: 0.55;
}
.rm-label {
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--rm-c, var(--terracotta));
}
.rm-title {
  margin: 0 0 2px !important;
  font-size: 15px !important;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text-strong);
  overflow-wrap: anywhere;
}
.rm-mod {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  padding: 9px 10px;
  border-radius: 9px;
  background: var(--bg-subtle);
  color: var(--text-main) !important;
  text-decoration: none !important;
  transition: background 0.15s ease;
}
.rm-mod:hover { background: color-mix(in srgb, var(--rm-c, #cc6644) 10%, var(--bg-subtle)); }
.rm-num {
  flex: none;
  font: 700 12px/1.6 var(--font-mono);
  color: var(--rm-c, var(--terracotta));
}
.rm-body { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.rm-body b { font-size: 13.5px; line-height: 1.45; overflow-wrap: anywhere; }
.rm-body small { font-size: 12px; line-height: 1.5; color: var(--text-muted); overflow-wrap: anywhere; }
@media (max-width: 991px) {
  .rm-roadmap { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .rm-stage:nth-child(2)::after { display: none; }
}
@media (max-width: 575px) {
  .rm-roadmap { grid-template-columns: 1fr; gap: 26px; }
  .rm-stage:not(:last-child)::after {
    display: block;
    top: auto; right: auto; bottom: -19px; left: 50%;
    transform: translateX(-50%) rotate(135deg);
  }
}

/* --------------------------------------------------------------------------
   Figure cards (.vfig): text figures built in Markdown so text stays at body
   size and formulas render as page math. Rules: 2–4 cards, ≤ 3 short lines each.
   -------------------------------------------------------------------------- */
.vfig {
  margin: 1.6rem 0 0.4rem;
  padding: 18px 18px 16px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 14px;
  box-shadow: var(--shadow-sm);
}
.vfig-title {
  margin: 0 0 14px;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-strong);
  text-align: center;
}
.vfig-title p { margin: 0; }
.vfig-grid {
  display: grid;
  grid-template-columns: repeat(var(--cols, 2), minmax(0, 1fr));
  gap: 14px;
}
.vfig-flow { gap: 30px; }
.vfig-card {
  --c: #cc6644;
  position: relative;
  min-width: 0;
  padding: 12px 14px 10px;
  background: color-mix(in srgb, var(--c) 5%, var(--bg-surface));
  border: 1px solid color-mix(in srgb, var(--c) 28%, transparent);
  border-top: 3px solid var(--c);
  border-radius: 10px;
  font-size: 14.5px;
  line-height: 1.6;
  overflow-wrap: anywhere;
}
.vfig-card.c-blue { --c: #2563eb; }
.vfig-card.c-green { --c: #15803d; }
.vfig-card.c-purple { --c: #7c3aed; }
.vfig-card.c-teal { --c: #0f766e; }
.vfig-card.c-orange { --c: #cc6644; }
.vfig-card.c-red { --c: #dc2626; }
.vfig-card.c-slate { --c: #64748b; }
.vfig-card > p:first-child { margin: 0 0 6px; color: var(--c); font-weight: 700; font-size: 15px; }
.vfig-card p { margin: 0 0 6px; }
.vfig-card ul, .vfig-card ol { margin: 0; padding-left: 1.15em; }
.vfig-card li { margin: 0 0 4px; }
.vfig-card li:last-child, .vfig-card p:last-child { margin-bottom: 0; }
.vfig-card .math.display, .vfig-key .math.display { overflow-x: auto; overflow-y: hidden; }
.vfig-card math[display="block"] { margin: 6px 0; font-size: 1em; }
.vfig-flow > .vfig-card:not(:last-child)::after {
  content: "";
  position: absolute;
  top: 50%;
  right: -21px;
  width: 11px;
  height: 11px;
  border-top: 2px solid var(--text-muted);
  border-right: 2px solid var(--text-muted);
  transform: translateY(-50%) rotate(45deg);
  opacity: 0.55;
}
.vfig-key {
  margin-top: 14px;
  padding: 10px 14px;
  background: var(--bg-subtle);
  border-radius: 10px;
  font-size: 14.5px;
  line-height: 1.6;
  text-align: center;
}
.vfig-key p { margin: 0; }
.vfig-key p + p { margin-top: 4px; }
body.quarto-dark .vfig-card { background: color-mix(in srgb, var(--c) 10%, var(--bg-surface)); }
/* chunk table used by the Reduce-Scatter / All-Gather figure */
.vfig-chunks { width: 100%; border-collapse: separate; border-spacing: 4px; font-size: 13.5px; text-align: center; }
.vfig-chunks th { font-weight: 600; color: var(--text-muted); padding: 2px 4px; white-space: nowrap; }
.vfig-chunks td { padding: 5px 4px; border-radius: 6px; background: var(--bg-subtle); white-space: nowrap; }
.vfig-chunks td.k0 { background: #dbeafe; color: #1e3a8a; }
.vfig-chunks td.k1 { background: #dcfce7; color: #14532d; }
.vfig-chunks td.k2 { background: #fef3c7; color: #78350f; }
.vfig-chunks td.k3 { background: #f3e8ff; color: #581c87; }
.vfig-chunks td.free { background: transparent; color: var(--text-muted); border: 1px dashed var(--border-light); }
body.quarto-dark .vfig-chunks td.k0 { background: #1e3a8a; color: #dbeafe; }
body.quarto-dark .vfig-chunks td.k1 { background: #14532d; color: #dcfce7; }
body.quarto-dark .vfig-chunks td.k2 { background: #78350f; color: #fef3c7; }
body.quarto-dark .vfig-chunks td.k3 { background: #581c87; color: #f3e8ff; }
@media (max-width: 767px) {
  .vfig-grid { grid-template-columns: 1fr; }
  .vfig-flow > .vfig-card:not(:last-child)::after {
    top: auto; right: auto; bottom: -21px; left: 50%;
    transform: translateX(-50%) rotate(135deg);
  }
}

/* --------------------------------------------------------------------------
   Excalidraw whiteboards rebuilt as HTML (scripts/excalidraw_to_html.py)
   -------------------------------------------------------------------------- */
.xboard {
  margin: 1.4rem 0 0.4rem;
  padding: 16px;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 14px;
  box-shadow: var(--shadow-sm);
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--text-main);
}
.xboard .xb-row { display: flex; flex-wrap: wrap; gap: 12px; margin: 10px 0; align-items: flex-start; }
.xboard, .xboard .xb-box { container-type: inline-size; }
.xboard .xb-row > .xb-box { flex: 1 1 220px; min-width: 0; }
.xboard .xb-flow { gap: 26px; }
.xboard .xb-flow > .xb-box { position: relative; }
.xboard .xb-flow > .xb-box:not(:last-child)::after {
  content: ""; position: absolute; top: 50%; right: -18px; width: 10px; height: 10px;
  border-top: 2px solid var(--text-muted); border-right: 2px solid var(--text-muted);
  transform: translateY(-50%) rotate(45deg); opacity: 0.55;
}
.xboard .xb-box {
  padding: 10px 12px;
  border: 1px solid color-mix(in srgb, var(--bc) 40%, transparent);
  border-top: 3px solid var(--bc);
  border-radius: 10px;
  background: color-mix(in srgb, var(--bc) 5%, var(--bg-surface));
  overflow-wrap: anywhere;
}
.xboard .xb-box[data-d="2"], .xboard .xb-box[data-d="3"] { border-top-width: 1px; background: var(--bg-surface); }
.xboard .xb-box.xb-dash { border-style: dashed; border-top-style: solid; }
.xboard .xb-box.xb-pill { border-radius: 18px; text-align: center; }
.xboard .xb-h1 { font-size: 17px; font-weight: 700; color: var(--tc, var(--text-strong)); margin: 2px 0 6px; }
.xboard > .xb-h1:first-child { text-align: center; }
.xboard .xb-h2 { font-size: 15px; font-weight: 700; color: var(--tc, var(--text-strong)); margin: 0 0 4px; }
.xboard .xb-t { margin: 0 0 4px; white-space: normal; }
.xboard .xb-t[data-a="c"], .xboard .xb-h2[data-a="c"] { text-align: center; }
.xboard .xb-mono { font-family: var(--font-mono); font-size: 13px; white-space: pre-wrap; text-align: left; }
.xboard .xb-row:first-child { margin-top: 0; }
@media (max-width: 767px) {
  .xboard .xb-row > .xb-box { flex-basis: 100%; }
  .xboard .xb-flow > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); }
}

/* a flow row that cannot fit on one line stacks vertically, and its chevrons point down */
@container (max-width: 465px) { .xboard .xb-flow.n2 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n2 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
@container (max-width: 711px) { .xboard .xb-flow.n3 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n3 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
@container (max-width: 957px) { .xboard .xb-flow.n4 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n4 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
@container (max-width: 1203px) { .xboard .xb-flow.n5 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n5 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
@container (max-width: 1449px) { .xboard .xb-flow.n6 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n6 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
@container (max-width: 1695px) { .xboard .xb-flow.n7 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n7 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
@container (max-width: 1941px) { .xboard .xb-flow.n8 > .xb-box { flex-basis: 100%; } .xboard .xb-flow.n8 > .xb-box:not(:last-child)::after { top: auto; right: auto; bottom: -18px; left: 50%; transform: translateX(-50%) rotate(135deg); } }
/* numbered steps / timeline points rebuilt from small badges */
.xboard .xb-steps > .xb-box { flex: 1 1 160px; }
.xboard .xb-step { position: relative; padding-top: 12px; }
.xboard .xb-num { display: inline-flex; align-items: center; justify-content: center; min-width: 24px; height: 24px; padding: 0 6px; margin: 0 0 6px; border-radius: 12px; background: var(--bc); color: #fff; font-weight: 700; font-size: 13px; }
.xboard .xb-dot { display: block; width: 12px; height: 12px; margin: 0 0 6px; border-radius: 50%; background: var(--bc); }
/* tables inside hand-written boards (scripts/excalidraw_manual.py) */
.xboard .xb-scroll { overflow-x: auto; margin: 6px 0 8px; }
.xboard .xb-table { width: 100%; border-collapse: collapse; font-size: 14px; line-height: 1.5; }
.xboard .xb-table th { text-align: left; font-weight: 700; color: var(--text-strong); background: var(--bg-subtle); padding: 6px 8px; border-bottom: 2px solid var(--border-light); white-space: nowrap; }
.xboard .xb-table td { padding: 6px 8px; border-bottom: 1px solid var(--border-light); vertical-align: top; min-width: 5.5em; }
.xboard .vfig-chunks th:first-child, .xboard .vfig-chunks td:first-child { text-align: left; white-space: nowrap; }
.xboard .xb-timeline td { white-space: normal; min-width: 6.5em; font-size: 13.5px; }
.xboard .xb-key { display: inline-block; padding: 0 6px; border-radius: 4px; font-size: 13px; }
.xboard .xb-key.k1 { background: #dcfce7; color: #14532d; }
.xboard .xb-key.k2 { background: #fef3c7; color: #78350f; }
.xboard .xb-key.k3 { background: #f3e8ff; color: #581c87; }
body.quarto-dark .xboard .xb-key.k1 { background: #14532d; color: #dcfce7; }
body.quarto-dark .xboard .xb-key.k2 { background: #78350f; color: #fef3c7; }
body.quarto-dark .xboard .xb-key.k3 { background: #581c87; color: #f3e8ff; }
.xboard sub, .xboard sup { font-size: 0.9em; }
@media (max-width: 480px) {
  .vfig-chunks { border-spacing: 2px; font-size: 13px; }
  .vfig-chunks th, .vfig-chunks td { white-space: normal; padding: 4px 2px; }
  .vfig-card { overflow-x: auto; }
}