/* ==========================================================================
   GOOGLE MATERIAL DESIGN 3 / GOOGLE CLOUD AESTHETIC DESIGN SYSTEM
   Clean, Minimalist Blue & White Theme for Semantic Harness
   ========================================================================== */

:root {
  /* Google Material 3 Core Tokens */
  --md-primary: #1a73e8;
  --md-primary-hover: #0b57d0;
  --md-primary-container: #e8f0fe;
  --md-on-primary-container: #041e49;
  
  --md-surface: #ffffff;
  --md-surface-subtle: #f8fafd;
  --md-surface-container: #f1f3f4;
  --md-surface-inset: #e8eaed;
  
  --md-outline: #dadce0;
  --md-outline-variant: #e0e3e7;
  
  --md-text-primary: #1f1f1f;
  --md-text-secondary: #444746;
  --md-text-tertiary: #747775;
  
  --md-green: #1e8e3e;
  --md-green-container: #e6f4ea;
  --md-red: #d93025;
  --md-red-container: #fce8e6;
  --md-warn: #e37400;
  --md-warn-container: #fef7e0;
  
  --code-bg: #1e1e24;
  --code-text: #e8eaed;

  /* Typography */
  --font-heading: 'Google Sans', 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'Fira Code', 'Google Sans Code', monospace;

  /* Elevations */
  --shadow-1: 0 1px 2px 0 rgba(60, 64, 67, 0.2), 0 1px 3px 1px rgba(60, 64, 67, 0.1);
  --shadow-2: 0 1px 3px 0 rgba(60, 64, 67, 0.3), 0 4px 8px 3px rgba(60, 64, 67, 0.12);
  --shadow-3: 0 4px 12px rgba(26, 115, 232, 0.15);
  
  /* Radii */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 9999px;

  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
}

/* Dark Theme Tokens */
body.dark-theme {
  --md-surface: #131316;
  --md-surface-subtle: #191a1e;
  --md-surface-container: #222328;
  --md-surface-inset: #2c2d33;
  
  --md-outline: #38393e;
  --md-outline-variant: #2e3036;
  
  --md-text-primary: #e3e3e3;
  --md-text-secondary: #c4c7c5;
  --md-text-tertiary: #8e918f;
  
  --md-primary-container: rgba(26, 115, 232, 0.2);
  --md-green-container: rgba(30, 142, 62, 0.2);
  --md-red-container: rgba(217, 48, 37, 0.2);
  --md-warn-container: rgba(227, 116, 0, 0.2);
  
  --code-bg: #0f1013;
  --shadow-1: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-2: 0 4px 12px rgba(0, 0, 0, 0.5);
  --shadow-3: 0 4px 16px rgba(0, 0, 0, 0.6);
}

/* Base Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background-color: var(--md-surface);
  color: var(--md-text-primary);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--md-text-primary);
  font-weight: 700;
  letter-spacing: -0.02em;
}

p {
  color: var(--md-text-secondary);
}

a {
  color: var(--md-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--md-primary-hover);
}

/* NAVBAR */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--md-outline-variant);
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

body.dark-theme .navbar {
  background-color: rgba(19, 19, 22, 0.9);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-logo {
  width: 34px;
  height: 34px;
  background-color: var(--md-primary);
  color: #fff;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  box-shadow: 0 2px 6px rgba(26, 115, 232, 0.3);
}

.small-logo {
  width: 26px;
  height: 26px;
  font-size: 0.8rem;
}

.brand-name {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  color: var(--md-text-primary);
  display: flex;
  align-items: center;
  gap: 6px;
}

.brand-name strong {
  color: var(--md-primary);
}

.version-tag {
  font-size: 0.72rem;
  font-weight: 600;
  background-color: var(--md-primary-container);
  color: var(--md-primary);
  padding: 2px 8px;
  border-radius: var(--radius-pill);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-item {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--md-text-secondary);
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  transition: all var(--transition-fast);
}

.nav-item:hover {
  color: var(--md-primary);
  background-color: var(--md-primary-container);
}

.nav-item.active {
  color: var(--md-primary);
  font-weight: 600;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  font-size: 0.82rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  border: 1px solid var(--md-outline);
  color: var(--md-text-primary);
  background-color: var(--md-surface);
  transition: all var(--transition-fast);
}

.chip:hover {
  border-color: var(--md-primary);
  color: var(--md-primary);
  box-shadow: var(--shadow-1);
}

.chip-pypi {
  background-color: var(--md-primary-container);
  border-color: transparent;
  color: var(--md-primary);
}

.theme-toggle-btn {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--md-outline);
  background: var(--md-surface);
  color: var(--md-text-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

.theme-toggle-btn:hover {
  background-color: var(--md-surface-container);
  color: var(--md-primary);
}

/* BUTTONS */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-size: 0.92rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  background-color: var(--md-primary);
  color: #fff;
  border: none;
  cursor: pointer;
  box-shadow: 0 1px 3px rgba(26, 115, 232, 0.3);
  transition: all var(--transition-fast);
}

.btn-primary:hover {
  background-color: var(--md-primary-hover);
  color: #fff;
  box-shadow: 0 4px 10px rgba(26, 115, 232, 0.4);
  transform: translateY(-1px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-size: 0.92rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  background-color: var(--md-surface);
  color: var(--md-text-primary);
  border: 1px solid var(--md-outline);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-secondary:hover {
  border-color: var(--md-primary);
  color: var(--md-primary);
  background-color: var(--md-surface-subtle);
}

/* HERO SECTION */
.hero {
  padding: 60px 0 40px;
  background: radial-gradient(circle at 50% 10%, var(--md-primary-container) 0%, transparent 65%);
  text-align: center;
}

.pill-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 20px;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline);
  box-shadow: var(--shadow-1);
}

.pill-blue {
  background-color: var(--md-primary-container);
  border-color: transparent;
  color: var(--md-primary);
}

.pill-green {
  background-color: var(--md-green-container);
  border-color: transparent;
  color: var(--md-green);
}

.hero-heading {
  font-size: 3rem;
  line-height: 1.15;
  margin-bottom: 18px;
  font-weight: 700;
}

.blue-gradient {
  background: linear-gradient(135deg, var(--md-primary) 0%, #1557b0 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-description {
  font-size: 1.15rem;
  max-width: 780px;
  margin: 0 auto 32px;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 40px;
}

.terminal-pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background-color: var(--code-bg);
  color: #fff;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  box-shadow: var(--shadow-1);
}

.term-prefix {
  color: var(--md-primary);
  font-weight: 700;
}

.icon-copy-btn {
  background: transparent;
  border: none;
  color: #9aa0a6;
  cursor: pointer;
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

.icon-copy-btn:hover {
  color: #fff;
}

/* STATS ROW */
.stats-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 10px;
  text-align: left;
}

.stat-card {
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  box-shadow: var(--shadow-1);
}

.stat-num {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
  margin-bottom: 6px;
}

.stat-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--md-text-primary);
  margin-bottom: 2px;
}

.stat-subtitle {
  font-size: 0.78rem;
  color: var(--md-text-secondary);
}

.text-blue { color: var(--md-primary); }
.text-accent { color: #1967d2; }
.text-green { color: var(--md-green); }
.text-error { color: var(--md-red); }

/* SECTIONS */
.section {
  padding: 70px 0;
}

.bg-subtle {
  background-color: var(--md-surface-subtle);
}

.section-title-box {
  margin-bottom: 40px;
}

.subheading {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--md-primary);
  background-color: var(--md-primary-container);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  display: inline-block;
  margin-bottom: 10px;
}

.section-title-box h2 {
  font-size: 2.1rem;
  margin-bottom: 10px;
}

.section-title-box p {
  font-size: 1rem;
  max-width: 680px;
  margin: 0 auto;
}

/* ==========================================================================
   INTERACTIVE SIMULATOR (CLEAN & INTUITIVE)
   ========================================================================== */
.interactive-card {
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-2);
  overflow: hidden;
}

/* SCENARIO CHIPS ROW */
.scenario-chips-row {
  padding: 12px 20px;
  background-color: var(--md-surface);
  border-bottom: 1px solid var(--md-outline-variant);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.chips-label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--md-text-primary);
  margin-right: 4px;
}

.scenario-chip {
  display: inline-flex;
  align-items: center;
  padding: 6px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  font-family: var(--font-body);
  border-radius: var(--radius-pill);
  border: 1px solid var(--md-outline);
  background-color: var(--md-surface-subtle);
  color: var(--md-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.scenario-chip:hover {
  border-color: var(--md-primary);
  color: var(--md-primary);
  background-color: var(--md-primary-container);
}

.scenario-chip.active {
  background-color: var(--md-primary);
  color: #fff;
  border-color: var(--md-primary);
  box-shadow: 0 1px 3px rgba(26, 115, 232, 0.3);
}

/* CONTROLS BAR */
.sim-controls-bar {
  padding: 16px 20px;
  background-color: var(--md-surface-container);
  border-bottom: 1px solid var(--md-outline-variant);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
}

.control-group {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
}

.control-group label {
  font-size: 0.85rem;
  font-weight: 600;
  white-space: nowrap;
  color: var(--md-text-primary);
}

.control-group select {
  width: 100%;
  padding: 8px 12px;
  font-size: 0.88rem;
  font-family: var(--font-body);
  border-radius: var(--radius-sm);
  border: 1px solid var(--md-outline);
  background-color: var(--md-surface);
  color: var(--md-text-primary);
  cursor: pointer;
}

.sim-run-btn {
  padding: 8px 18px;
}

.custom-prompt-row {
  padding: 12px 20px;
  background-color: var(--md-surface-subtle);
  border-bottom: 1px solid var(--md-outline-variant);
  display: flex;
  gap: 12px;
}

.custom-prompt-row input {
  flex: 1;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--md-outline);
  font-family: var(--font-body);
  font-size: 0.9rem;
  background: var(--md-surface);
  color: var(--md-text-primary);
}

/* ANIMATED STEP PIPELINE */
.sim-pipeline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  background-color: var(--md-surface);
  border-bottom: 1px solid var(--md-outline-variant);
  overflow-x: auto;
}

.pipe-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  min-width: 110px;
  opacity: 0.4;
  transition: all var(--transition-normal);
}

.pipe-step.active-step {
  opacity: 1;
}

.pipe-step.active-step .step-circle {
  background-color: var(--md-primary);
  color: #fff;
  transform: scale(1.1);
  box-shadow: 0 0 12px rgba(26, 115, 232, 0.4);
}

.step-circle {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-pill);
  background-color: var(--md-surface-container);
  color: var(--md-text-secondary);
  font-size: 0.8rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

.step-label {
  font-size: 0.75rem;
  font-weight: 600;
  text-align: center;
}

.pipe-line {
  flex: 1;
  height: 2px;
  background-color: var(--md-outline-variant);
  margin: 0 8px;
  margin-bottom: 22px;
}

/* COMPARISON DASHBOARD */
.sim-dashboard {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
  padding: 24px;
}

.system-col {
  background-color: var(--md-surface-subtle);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--radius-md);
  padding: 18px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.col-highlight {
  border: 2px solid var(--md-primary);
  background-color: var(--md-primary-container);
  box-shadow: var(--shadow-3);
}

.system-col-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.sys-title {
  font-size: 0.95rem;
  font-weight: 700;
  font-family: var(--font-heading);
}

.sys-badge {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
}

.bg-bad { background: var(--md-red-container); color: var(--md-red); }
.bg-warn { background: var(--md-warn-container); color: var(--md-warn); }
.bg-blue { background: var(--md-primary); color: #fff; }

.telemetry-box {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 16px;
  font-size: 0.88rem;
}

.tel-item {
  display: flex;
  justify-content: space-between;
  padding-bottom: 4px;
  border-bottom: 1px dashed var(--md-outline-variant);
}

.tel-label {
  color: var(--md-text-secondary);
}

.tel-val {
  font-weight: 600;
  font-family: var(--font-mono);
}

.sys-result-card {
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--radius-sm);
  padding: 12px;
}

.border-error { border-color: var(--md-red); }
.border-green { border-color: var(--md-green); }
.bg-green-subtle { background-color: var(--md-surface); }

.card-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--md-text-tertiary);
  margin-bottom: 2px;
}

.card-val {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.card-status {
  font-size: 0.78rem;
  font-weight: 600;
}

.status-ok { color: var(--md-green); }
.status-error { color: var(--md-red); }

/* TRACE INSPECTOR */
.trace-container {
  background-color: var(--code-bg);
  border-top: 1px solid var(--md-outline);
}

.trace-header {
  padding: 10px 20px;
  background-color: rgba(0, 0, 0, 0.2);
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #9aa0a6;
  font-size: 0.8rem;
}

.badge-pill-small {
  background-color: rgba(26, 115, 232, 0.3);
  color: #8ab4f8;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  font-size: 0.72rem;
  font-weight: 600;
}

.trace-pre {
  padding: 16px 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--code-text);
  line-height: 1.5;
}

/* ==========================================================================
   4 PILLARS GRID
   ========================================================================== */
.pillars-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.pillar-card {
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-1);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

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

.pillar-icon {
  font-size: 1.6rem;
  margin-bottom: 14px;
}

.pillar-card h3 {
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.pillar-card p {
  font-size: 0.9rem;
  line-height: 1.5;
}

/* ==========================================================================
   5-LAYER STACK LIST
   ========================================================================== */
.stack-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-width: 860px;
  margin: 0 auto;
}

.stack-row {
  display: flex;
  align-items: center;
  gap: 16px;
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.stack-row:hover {
  border-color: var(--md-primary);
  box-shadow: var(--shadow-1);
}

.stack-row.active {
  border-color: var(--md-primary);
  background-color: var(--md-primary-container);
}

.stack-num {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--md-primary);
  background-color: var(--md-surface);
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--md-outline-variant);
  white-space: nowrap;
}

.stack-main {
  flex: 1;
}

.stack-main h4 {
  font-size: 0.98rem;
  margin-bottom: 2px;
}

.stack-main p {
  font-size: 0.85rem;
}

.stack-chevron {
  color: var(--md-text-tertiary);
  font-size: 0.85rem;
}

/* ==========================================================================
   BENCHMARK TAB VIEWER
   ========================================================================== */
.tab-card {
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-2);
  max-width: 960px;
  margin: 0 auto;
}

.tab-nav {
  display: flex;
  flex-wrap: wrap;
  background-color: var(--md-surface-container);
  border-bottom: 1px solid var(--md-outline-variant);
  padding: 6px;
  gap: 6px;
}

.tab-btn {
  padding: 8px 16px;
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  border: none;
  background: transparent;
  color: var(--md-text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-fast);
}

.tab-btn:hover {
  color: var(--md-primary);
  background-color: rgba(26, 115, 232, 0.08);
}

.tab-btn.active {
  background-color: var(--md-primary);
  color: #fff;
}

.tab-viewport {
  padding: 24px;
}

.fig-panel {
  display: none;
  text-align: center;
}

.fig-panel.active {
  display: block;
}

.fig-img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--md-outline-variant);
  margin-bottom: 16px;
}

.fig-caption {
  text-align: left;
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--md-text-secondary);
}

.fig-caption strong {
  color: var(--md-text-primary);
}

/* ==========================================================================
   CODE RECIPES
   ========================================================================== */
.code-card {
  background-color: var(--code-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-2);
  max-width: 960px;
  margin: 0 auto;
}

.code-tabs-nav {
  display: flex;
  background-color: rgba(0, 0, 0, 0.3);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  overflow-x: auto;
}

.code-tab-btn {
  padding: 12px 18px;
  font-size: 0.85rem;
  font-weight: 600;
  border: none;
  background: transparent;
  color: #9aa0a6;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: all var(--transition-fast);
}

.code-tab-btn:hover {
  color: #fff;
}

.code-tab-btn.active {
  color: #8ab4f8;
  border-bottom-color: var(--md-primary);
  background-color: rgba(255, 255, 255, 0.04);
}

.code-box {
  display: none;
}

.code-box.active {
  display: block;
}

.code-bar {
  padding: 8px 18px;
  background-color: rgba(0, 0, 0, 0.2);
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #80868b;
  font-size: 0.78rem;
  font-family: var(--font-mono);
}

.copy-btn {
  background: transparent;
  border: none;
  color: #9aa0a6;
  font-size: 0.8rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 4px;
}

.copy-btn:hover {
  color: #fff;
}

.code-box pre {
  padding: 18px 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.55;
  color: var(--code-text);
}

/* ==========================================================================
   PAPER & CITATION
   ========================================================================== */
.paper-layout {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 24px;
  background-color: var(--md-surface);
  border: 1px solid var(--md-outline);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-2);
}

@media (max-width: 860px) {
  .paper-layout {
    grid-template-columns: 1fr;
  }
}

.paper-badge-line {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.paper-h3 {
  font-size: 1.2rem;
  margin-bottom: 10px;
  line-height: 1.35;
}

.paper-meta {
  font-size: 0.88rem;
  margin-bottom: 20px;
}

.paper-btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.bibtex-col {
  background-color: var(--code-bg);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.bibtex-bar {
  padding: 8px 14px;
  background-color: rgba(0, 0, 0, 0.2);
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #9aa0a6;
  font-size: 0.78rem;
  font-weight: 600;
}

.bibtex-code {
  padding: 14px 16px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.45;
  color: var(--code-text);
  overflow-x: auto;
}

/* FOOTER */
.footer {
  border-top: 1px solid var(--md-outline-variant);
  padding: 32px 0;
  background-color: var(--md-surface);
  font-size: 0.85rem;
}

.footer-content {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.footer-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-center {
  display: flex;
  gap: 16px;
}

.footer-right {
  color: var(--md-text-tertiary);
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .hero-heading { font-size: 2.1rem; }
  .nav-menu { display: none; }
  .hide-mobile { display: none; }
}