/* ==========================================================================
   leslieli.dev — Minimalist Modern Design System
   ========================================================================== */

:root {
  /* Color Tokens - Zen Washi Light Mode (Default) */
  --bg: #fafaf8;
  --bg-elevated: #ffffff;
  --bg-card: #f3f3ee;
  --bg-card-hover: #eaeae4;
  --bg-subtle: #f0f0eb;
  
  --ink: #18181b;
  --ink-secondary: #27272a;
  --muted: #71717a;
  --muted-light: #a1a1aa;
  
  --line: rgba(0, 0, 0, 0.06);
  --line-strong: rgba(0, 0, 0, 0.12);
  --line-glow: rgba(180, 83, 9, 0.18);
  
  --accent: #b45309;
  --accent-hover: #92400e;
  --accent-subtle: rgba(180, 83, 9, 0.08);
  --accent-cyan: #0284c7;
  --accent-cyan-subtle: rgba(2, 132, 199, 0.08);
  --success: #15803d;
  --success-subtle: rgba(21, 128, 61, 0.08);
  --accent-green: #16a34a;
  --on-accent: #000000;

  /* Shadows */
  --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.09);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.14);

  /* Typography */
  --font-display: "Space Grotesk", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: "Newsreader", "Iowan Old Style", Palatino, serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", "SFMono-Regular", Menlo, monospace;

  /* Layout & Measurements */
  --measure: 56rem;
  --measure-wide: 64rem;
  --space-unit: clamp(1rem, 2.5vw, 1.5rem);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 250ms cubic-bezier(0.16, 1, 0.3, 1);
}

/* Explicit Light Mode */
[data-theme="light"] {
  --bg: #fafaf8;
  --bg-elevated: #ffffff;
  --bg-card: #f3f3ee;
  --bg-card-hover: #eaeae4;
  --bg-subtle: #f0f0eb;
  
  --ink: #18181b;
  --ink-secondary: #27272a;
  --muted: #71717a;
  --muted-light: #a1a1aa;
  
  --line: rgba(0, 0, 0, 0.06);
  --line-strong: rgba(0, 0, 0, 0.12);
  --line-glow: rgba(180, 83, 9, 0.18);
  
  --accent: #b45309;
  --accent-hover: #92400e;
  --accent-subtle: rgba(180, 83, 9, 0.08);
  --accent-cyan: #0284c7;
  --accent-cyan-subtle: rgba(2, 132, 199, 0.08);
  --success: #15803d;
  --success-subtle: rgba(21, 128, 61, 0.08);
}

/* Dark Mode Overrides (Sumi Ink & Obsidian) */
[data-theme="dark"] {
  --bg: #09090b;
  --bg-elevated: #111114;
  --bg-card: #141418;
  --bg-card-hover: #1b1b22;
  --bg-subtle: #18181e;
  
  --ink: #f4f4f6;
  --ink-secondary: #d4d4d8;
  --muted: #828290;
  --muted-light: #52525b;
  
  --line: rgba(255, 255, 255, 0.06);
  --line-strong: rgba(255, 255, 255, 0.12);
  --line-glow: rgba(217, 119, 6, 0.2);
  
  --accent: #d97706;
  --accent-hover: #f59e0b;
  --accent-subtle: rgba(217, 119, 6, 0.1);
  --accent-cyan: #38bdf8;
  --accent-cyan-subtle: rgba(56, 189, 248, 0.1);
  --success: #10b981;
  --success-subtle: rgba(16, 185, 129, 0.1);
  --accent-green: #22c55e;

  /* Shadows */
  --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.55);
}

/* Base Reset */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  min-height: 100vh;
  background-color: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  letter-spacing: -0.012em;
  transition: background-color var(--transition-smooth), color var(--transition-smooth);
}

/* Scroll Progress Bar */
#scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 2px;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-cyan));
  z-index: 100;
  transition: width 0.1s ease-out;
}

/* Skip link for accessibility */
.skip-link {
  position: absolute;
  top: -3rem;
  left: 1.5rem;
  z-index: 1000;
  padding: 0.5rem 1rem;
  background: var(--ink);
  color: var(--bg);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: top var(--transition-fast);
}
.skip-link:focus {
  top: 1rem;
}

/* Links */
a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  max-width: var(--measure-wide);
  margin: 0 auto;
  padding: 1rem clamp(1rem, 3vw, 2rem);
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.brand-monogram {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.85rem;
  height: 1.85rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.brand:hover .brand-monogram {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
}

.nav a {
  color: var(--muted);
  padding: 0.25rem 0.4rem;
  border-radius: var(--radius-sm);
}

.nav a:hover,
.nav a:focus-visible,
.nav a[aria-current="page"] {
  color: var(--ink);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.status-pill-clock {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.25rem 0.65rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-full);
  background: var(--bg-card);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.02em;
}

.status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 8px var(--success);
  animation: pulse-dot 2.5s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--muted);
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.theme-toggle:hover {
  color: var(--ink);
  border-color: var(--line-strong);
  background: var(--bg-card-hover);
}

.theme-toggle svg {
  width: 1rem;
  height: 1rem;
  fill: currentColor;
}

/* ==========================================================================
   Main Layout & Sections
   ========================================================================== */
main {
  width: 100%;
  max-width: var(--measure);
  margin: 0 auto;
  padding: 0 clamp(1rem, 3vw, 2rem) 6rem;
}

/* Hero Section */
.hero {
  padding: clamp(3.5rem, 8vw, 6.5rem) 0 clamp(2.5rem, 6vw, 4rem);
  border-bottom: 1px solid var(--line);
}

.hero-status {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  padding: 0.45rem 0.9rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-full);
  background: var(--bg-card);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ink-secondary);
}

.hero-status-lines {
  line-height: 1.4;
}

.hero h1 {
  margin: 0 0 1.25rem;
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 6.5vw, 4.4rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.04em;
  color: var(--ink);
}

.hero h1 .highlight {
  color: var(--accent);
}

.hero-lede {
  max-width: 42rem;
  margin: 0 0 2rem;
  font-family: var(--font-serif);
  font-size: clamp(1.15rem, 2vw, 1.35rem);
  line-height: 1.65;
  color: var(--muted);
}

.hero-meta-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
}

.button {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 1rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
}

.button:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}

.button-primary {
  background: var(--ink);
  color: var(--bg);
  border-color: var(--ink);
}

.button-primary:hover {
  background: var(--accent);
  color: var(--on-accent);
  border-color: var(--accent);
}

.meta-link {
  color: var(--muted);
  text-decoration: underline;
  text-underline-offset: 0.25em;
}
.meta-link:hover {
  color: var(--ink);
}

/* ==========================================================================
   Section Headers & Grid Layout
   ========================================================================== */
.section {
  padding-top: clamp(3.5rem, 7vw, 5rem);
}

.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 2rem;
  gap: 1rem;
}

.eyebrow {
  margin: 0 0 0.4rem;
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.section-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.15;
}

.section-desc {
  margin: 0.5rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
  max-width: 36rem;
}

/* ==========================================================================
   Work / Research Tracks (Minimalist Grid)
   ========================================================================== */
.track-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
}

.track-card {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 1.5rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--bg-card);
  transition: border-color var(--transition-smooth), background-color var(--transition-smooth), transform var(--transition-smooth), box-shadow var(--transition-smooth);
}

.track-card:hover {
  border-color: var(--line-strong);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.track-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.track-index {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-full);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.badge-active {
  background: var(--success-subtle);
  color: var(--success);
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.badge-lab {
  background: var(--accent-cyan-subtle);
  color: var(--accent-cyan);
  border: 1px solid rgba(56, 189, 248, 0.2);
}

.badge-writing {
  background: var(--accent-subtle);
  color: var(--accent);
  border: 1px solid rgba(245, 158, 11, 0.2);
}

.track-title {
  margin: 0 0 0.65rem;
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.track-desc {
  margin: 0 0 1.25rem;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.55;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.tags li {
  padding: 0.15rem 0.45rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  background: var(--bg);
}

/* ==========================================================================
   Notes / Log List (Minimalist Editorial Feed)
   ========================================================================== */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.filter-btn {
  padding: 0.35rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-full);
  background: transparent;
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.filter-btn:hover,
.filter-btn.active {
  color: var(--ink);
  border-color: var(--line-strong);
  background: var(--bg-card);
}

.note-feed {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.note-feed-item {
  border-bottom: 1px solid var(--line);
  transition: background-color var(--transition-fast);
}

.note-feed-link {
  display: grid;
  grid-template-columns: 8.5rem 1fr auto;
  align-items: baseline;
  gap: 1.25rem;
  padding: 1.25rem 0.5rem;
  text-decoration: none;
  border-radius: var(--radius-sm);
}

.note-feed-item:hover {
  background: var(--bg-card);
}

.note-feed-item:hover .note-feed-title {
  color: var(--accent);
}

.note-feed-date {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
  white-space: nowrap;
}

.note-feed-main {
  min-width: 0;
}

.note-feed-title {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 500;
  letter-spacing: -0.015em;
  color: var(--ink);
  transition: color var(--transition-fast);
}

.note-feed-desc {
  margin: 0;
  font-size: 0.88rem;
  color: var(--muted);
  line-height: 1.5;
}

.note-feed-meta {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted-light);
}

.arrow-icon {
  font-family: var(--font-mono);
  color: var(--muted);
  transition: transform var(--transition-fast), color var(--transition-fast);
}

.note-feed-item:hover .arrow-icon {
  color: var(--accent);
  transform: translateX(4px);
}

.note-feed-item.is-revealed {
  animation: noteFadeIn 0.35s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes noteFadeIn {
  from {
    opacity: 0;
    transform: translateY(6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.notes-expand-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 1.5rem;
  padding-top: 1rem;
  border-top: 1px dashed var(--line);
}

.button-view-more {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.25rem;
  background: var(--bg-card);
  color: var(--ink);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast);
}

.button-view-more:hover {
  background: var(--ink);
  color: var(--bg);
  border-color: var(--ink);
  transform: translateY(-1px);
}

.button-view-more svg {
  transition: transform var(--transition-fast);
}

.button-view-more.is-expanded svg {
  transform: rotate(180deg);
}

@media (max-width: 640px) {
  .notes-expand-bar {
    flex-direction: column;
    align-items: stretch;
    text-align: center;
    gap: 0.85rem;
  }
  .button-view-more {
    justify-content: center;
  }
}

/* ==========================================================================
   Specs / Hardware Rig Table
   ========================================================================== */
.spec-box {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
  padding: 1.5rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--bg-card);
}

.spec-column h4 {
  margin: 0 0 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.spec-list {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 0.88rem;
  color: var(--ink-secondary);
}

.spec-list li {
  display: flex;
  justify-content: space-between;
  padding: 0.4rem 0;
  border-bottom: 1px dashed var(--line);
}

.spec-list li:last-child {
  border-bottom: none;
}

.spec-label {
  color: var(--muted);
}

.spec-val {
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

/* ==========================================================================
   About & Contact
   ========================================================================== */
.about-card {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  padding: 2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--bg-card);
}

.about-card p {
  margin: 0 0 1rem;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.65;
}

.about-card p:last-child {
  margin-bottom: 0;
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

/* Toast feedback for email copy */
#toast {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 1000;
  padding: 0.65rem 1.15rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--bg-elevated);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: opacity var(--transition-smooth), transform var(--transition-smooth);
}

#toast.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   Article / Note Template Pages
   ========================================================================== */
.article-container {
  max-width: 44rem;
  margin: 0 auto;
  padding-top: clamp(2.5rem, 6vw, 4rem);
}

.article-breadcrumb {
  margin-bottom: 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
}

.article-breadcrumb a:hover {
  color: var(--accent);
}

.article-header {
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 2rem;
}

.article-header h1 {
  margin: 0 0 1.25rem;
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.03em;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
}

.article-body {
  font-size: 1.06rem;
  line-height: 1.75;
  color: var(--ink-secondary);
}

.article-body p {
  margin: 0 0 1.4rem;
}

.article-body h2 {
  margin: 2.5rem 0 1rem;
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.article-body h3 {
  margin: 2rem 0 0.75rem;
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.article-body ul, 
.article-body ol {
  margin: 0 0 1.5rem;
  padding-left: 1.4rem;
}

.article-body li {
  margin-bottom: 0.75rem;
}

.article-body strong {
  color: var(--ink);
  font-weight: 600;
}

.article-body code {
  padding: 0.2rem 0.4rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.88em;
}

.article-body pre {
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--bg-card);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.6;
}

.article-body pre code {
  padding: 0;
  border: none;
  background: transparent;
  color: var(--ink);
}

.article-body blockquote {
  margin: 1.5rem 0;
  padding: 0.9rem 1.35rem;
  border-left: 2px solid var(--accent);
  background: var(--bg-card);
  color: var(--muted);
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-style: italic;
}

.article-body figure {
  margin: 2rem 0;
  padding: 0;
}

.article-body figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
}

.article-body figcaption {
  margin-top: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--muted);
  text-align: center;
}

.article-body table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.article-body th,
.article-body td {
  text-align: left;
  vertical-align: top;
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--line);
}

.article-body th {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  background: var(--bg-subtle);
}

.article-body td:first-child {
  font-weight: 600;
  width: 32%;
  color: var(--ink);
}

.rl-glossary {
  display: grid;
  gap: 0.75rem;
  margin: 1rem 0 2rem;
}

.rl-glossary-item {
  margin: 0;
  padding: 1rem 1.15rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg-elevated);
}

.rl-glossary-item dt {
  font-family: var(--font-mono);
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.rl-glossary-item dd {
  margin: 0.4rem 0 0;
  font-size: 0.92rem;
  line-height: 1.55;
  color: var(--ink-secondary);
}

.rl-glossary-item dd span {
  display: block;
  margin-top: 0.45rem;
  padding-top: 0.45rem;
  border-top: 1px dashed var(--line-strong);
  font-size: 0.86rem;
  color: var(--muted);
}

.rl-glossary-item dd span::before {
  content: "In LLM terms — ";
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
}

.article-footer {
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.article-share {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding-bottom: 2rem;
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--line);
}

.article-share-label {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--muted);
}

.share-btn-linkedin {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.95rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  text-decoration: none;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
}

.share-btn-linkedin:hover {
  background: var(--bg-card-hover);
  border-color: #0a66c2;
  color: #0a66c2;
  transform: translateY(-1px);
}

.share-btn-linkedin svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
}

/* ==========================================================================
   Site Footer
   ========================================================================== */
.site-footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  max-width: var(--measure);
  margin: 0 auto;
  padding: 2rem clamp(1rem, 3vw, 2rem) 3rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.78rem;
}

.site-footer a:hover {
  color: var(--ink);
}

.footer-nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */
@media (max-width: 768px) {
  .site-header {
    gap: 0.75rem;
  }
  
  .status-pill-clock {
    display: none;
  }
  
  .nav {
    gap: 0.75rem;
    font-size: 0.75rem;
  }
  
  .note-feed-link {
    grid-template-columns: 1fr;
    gap: 0.4rem;
  }
  
  .note-feed-meta {
    margin-top: 0.25rem;
  }
  
  .arrow-icon {
    display: none;
  }
  
  .about-card {
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 1.5rem;
  }
}

/* ==========================================================================
   Interactive Simulation & Visualizer Deck
   ========================================================================== */
.sim-container {
  margin: 2.5rem 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transition: border-color var(--transition-fast);
}

.sim-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--line);
}

.sim-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--ink);
}

.sim-modes {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.sim-mode-btn {
  padding: 0.35rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.sim-mode-btn:hover {
  color: var(--ink);
  border-color: var(--line-strong);
  background: var(--bg-card-hover);
}

.sim-mode-btn.active {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-subtle);
  font-weight: 600;
}

.sim-canvas-wrap {
  position: relative;
  width: 100%;
  height: 480px;
  background: #020205;
  overflow: hidden;
}

.sim-canvas-wrap canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.sim-overlay-hint {
  position: absolute;
  top: 1rem;
  right: 1rem;
  padding: 0.3rem 0.6rem;
  border-radius: var(--radius-sm);
  background: rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: #a1a1aa;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  pointer-events: none;
}

.sim-hud {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 0.5rem;
  padding: 1rem 1.25rem;
  background: var(--bg-elevated);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.sim-hud-tile {
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  border: 1px solid var(--line);
}

.sim-hud-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.2rem;
}

.sim-hud-value {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
}

.sim-hud-value.status-safe {
  color: var(--success);
}

.sim-hud-value.status-warning {
  color: var(--accent);
}

.sim-hud-value.status-danger {
  color: #ef4444;
}

.sim-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: var(--bg-card);
}

.sim-slider-group {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 1;
  min-width: 240px;
}

.sim-slider-group label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
  white-space: nowrap;
}

.sim-slider {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  border-radius: 3px;
  background: var(--line-strong);
  outline: none;
}

.sim-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  box-shadow: 0 0 8px var(--accent);
  transition: transform 0.1s;
}

.sim-slider::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

.sim-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.sim-commentary {
  padding: 1.25rem;
  background: var(--bg-subtle);
  border-top: 1px solid var(--line);
  font-size: 0.92rem;
  line-height: 1.6;
}

.sim-commentary-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.4rem;
}

.sim-commentary p {
  margin: 0;
  color: var(--ink-secondary);
}

/* ==========================================================================
   Newsletter & Subscription Component Design System
   ========================================================================== */

.newsletter-card {
  background: var(--bg-card);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  padding: clamp(1.75rem, 4vw, 2.75rem);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-smooth), box-shadow var(--transition-smooth);
}

.newsletter-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent-cyan), transparent);
  opacity: 0.8;
}

.newsletter-card:hover {
  border-color: var(--line-glow);
  box-shadow: var(--shadow-md);
}

.newsletter-header {
  margin-bottom: 1.5rem;
}

.newsletter-title {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3vw, 1.85rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0.35rem 0 0.5rem;
  color: var(--ink);
}

.newsletter-desc {
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.6;
  max-width: 38rem;
  margin: 0;
}

.newsletter-form {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-top: 1.25rem;
}

.newsletter-input-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.newsletter-input {
  flex: 1 1 240px;
  background: var(--bg-elevated);
  border: 1px solid var(--line-strong);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.92rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.newsletter-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-subtle);
}

.newsletter-input::placeholder {
  color: var(--muted-light);
  font-family: var(--font-body);
}

.newsletter-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background: var(--accent);
  color: #ffffff;
  border: none;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.92rem;
  padding: 0.75rem 1.4rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--transition-fast), transform var(--transition-fast);
}

.newsletter-btn:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.newsletter-btn:active {
  transform: translateY(0);
}

.newsletter-btn:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  transform: none;
}

.newsletter-spinner {
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: #ffffff;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.newsletter-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-top: 0.75rem;
  font-size: 0.82rem;
  color: var(--muted);
}

.newsletter-meta span {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.newsletter-rss-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  text-decoration: none;
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-sm);
  background: var(--accent-subtle);
  transition: background var(--transition-fast);
}

.newsletter-rss-link:hover {
  background: var(--line-glow);
  text-decoration: none;
}

.newsletter-feedback {
  display: none;
  margin-top: 1rem;
  padding: 0.85rem 1.1rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  line-height: 1.5;
  animation: fadeIn 0.25s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

.newsletter-feedback.is-success {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  background: var(--success-subtle);
  border: 1px solid var(--success);
  color: var(--ink);
}

.newsletter-feedback.is-error {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  background: rgba(220, 38, 38, 0.08);
  border: 1px solid #dc2626;
  color: #dc2626;
}

/* Article Footer Callout */
.article-newsletter {
  margin-top: 3.5rem;
  margin-bottom: 2.5rem;
}

/* Dedicated Subscribe Page */
.subscribe-hero {
  padding-top: clamp(2.5rem, 6vw, 4rem);
  margin-bottom: 2.5rem;
}

.subscribe-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
  margin: 2.5rem 0;
}

.subscribe-pillar-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  transition: border-color var(--transition-smooth), transform var(--transition-smooth);
}

.subscribe-pillar-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.subscribe-pillar-icon {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
}

.subscribe-pillar-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  margin: 0 0 0.4rem;
  color: var(--ink);
}

.subscribe-pillar-desc {
  font-size: 0.88rem;
  color: var(--muted);
  line-height: 1.55;
  margin: 0;
}

/* ==========================================================================
   16. Bookshelf & Reading Pipeline
   ========================================================================== */

.bookshelf-stats-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1rem;
  margin: 2rem 0;
}

.b-stat-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-smooth), transform var(--transition-smooth);
}

.b-stat-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.b-stat-number {
  font-family: var(--font-display);
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1;
  color: var(--ink);
}

.b-stat-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--muted);
}

.bookshelf-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 2rem;
  margin: 2.5rem 0;
}

.book-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-smooth), transform var(--transition-smooth), box-shadow var(--transition-smooth);
  position: relative;
}

.book-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}

.book-cover-wrap {
  position: relative;
  width: 100%;
  aspect-ratio: 2 / 3;
  overflow: hidden;
  background: var(--bg-elevated);
}

.book-cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform var(--transition-smooth);
}

.book-card:hover .book-cover-img {
  transform: scale(1.03);
}

.book-spine-sheen {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 24px;
  background: linear-gradient(90deg, rgba(0, 0, 0, 0.25) 0%, rgba(255, 255, 255, 0.15) 30%, transparent 100%);
  pointer-events: none;
}

.book-status-badge {
  position: absolute;
  top: 12px;
  right: 12px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-full);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow-lg);
}

.status-reading {
  background: rgba(22, 163, 74, 0.9);
  color: #ffffff;
}

.status-completed {
  background: rgba(37, 99, 235, 0.9);
  color: #ffffff;
}

.book-info {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.book-meta-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.6rem;
}

.book-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-subtle);
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-full);
}

.book-year {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
}

.book-title {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--ink);
  margin: 0 0 0.35rem;
}

.book-author {
  font-size: 0.88rem;
  color: var(--ink-secondary);
  margin: 0 0 1.25rem;
}

.book-progress-box {
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 0.75rem;
  margin-bottom: 1.25rem;
}

.book-progress-track {
  height: 6px;
  background: var(--line-strong);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 0.4rem;
}

.book-progress-fill {
  height: 100%;
  background: var(--accent-green, #16a34a);
  border-radius: var(--radius-full);
  transition: width 0.8s ease-in-out;
}

.book-progress-fill.completed {
  background: var(--accent);
}

.book-progress-labels {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
}

.book-progress-percent {
  font-weight: 600;
  color: var(--accent-green, #16a34a);
}

.book-takeaway {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 0.92rem;
  line-height: 1.55;
  color: var(--muted);
  margin: 0;
  padding-top: 0.75rem;
  border-top: 1px solid var(--line);
}

/* Homepage Compact Desk Bookshelf Layout */
.desk-books-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.25rem;
  margin: 1.75rem 0;
}

.desk-book-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 1rem 1.15rem;
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 1.15rem;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-smooth), transform var(--transition-smooth), box-shadow var(--transition-smooth);
  position: relative;
}

.desk-book-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.desk-cover-wrap {
  position: relative;
  width: 88px;
  min-width: 88px;
  max-width: 88px;
  height: 132px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background: var(--bg-elevated);
  flex-shrink: 0;
}

.desk-cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform var(--transition-smooth);
}

.desk-book-card:hover .desk-cover-img {
  transform: scale(1.04);
}

.desk-book-info {
  display: flex;
  flex-direction: column;
  flex-grow: 1;
  min-width: 0;
}

.desk-meta-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.35rem;
}

.desk-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-subtle);
  padding: 0.15rem 0.45rem;
  border-radius: var(--radius-full);
}

.desk-title {
  font-family: var(--font-display);
  font-size: 0.98rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--ink);
  margin: 0 0 0.2rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.desk-author {
  font-size: 0.8rem;
  color: var(--muted);
  margin: 0 0 0.65rem;
}

.desk-progress-box {
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 0.45rem 0.6rem;
  margin-top: 0.25rem;
}

.desk-progress-track {
  height: 4px;
  background: var(--line-strong);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 0.25rem;
}

.desk-progress-fill {
  height: 100%;
  background: var(--accent-green, #16a34a);
  border-radius: var(--radius-full);
}

.desk-progress-fill.completed {
  background: var(--accent);
}

.desk-progress-labels {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--muted);
}