@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500&display=swap');

  :root {
    --h2-primary: #0066CC;
    --h2-dark: #003D7A;
    --h2-light: #E8F4FD;
    --h2-accent: #00A3E0;
    --propane-primary: #D4520A;
    --propane-dark: #8B3506;
    --propane-light: #FFF3EC;
    --propane-accent: #FF7A2F;
    --strat-primary: #2D6A4F;
    --strat-dark: #1B4332;
    --strat-light: #E8F5EE;
    --eng-primary: #6B21A8;
    --eng-dark: #4C1D95;
    --eng-light: #F3E8FF;
    --semi-primary: #334155;
    --semi-dark: #1e293b;
    --semi-light: #f1f5f9;
    --semi-accent: #475569;
    --text: #1A1A2E;
    --text-secondary: #4A4A6A;
    --bg: #FAFBFC;
    --white: #FFFFFF;
    --border: #E2E8F0;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.10);
  }

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

  body {
    font-family: 'Inter', -apple-system, sans-serif;
    font-size: 10pt;
    line-height: 1.6;
    color: var(--text);
    background: var(--white);
  }

  .page-break { page-break-before: always; }

  /* COVER x Enhanced Hero */
  @keyframes heroFloat1 { 0%,100%{ transform: translate(0,0) scale(1); } 50%{ transform: translate(30px,-20px) scale(1.05); } }
  @keyframes heroFloat2 { 0%,100%{ transform: translate(0,0) scale(1); } 50%{ transform: translate(-25px,15px) scale(0.95); } }
  @keyframes heroFloat3 { 0%,100%{ transform: translate(0,0); } 50%{ transform: translate(15px,25px); } }
  @keyframes particlePulse { 0%,100%{ opacity:.35; } 50%{ opacity:.7; } }
  @keyframes barGrow { from { width:0; } to { width:200px; } }
  @keyframes fadeInUp { from { opacity:0; transform:translateY(24px); } to { opacity:1; transform:translateY(0); } }

  .cover {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, #0a1628 0%, #0f1f3d 20%, #1a2d5a 40%, #162444 55%, #0d2a3f 70%, #0a1628 100%);
    color: white;
    text-align: center;
    padding: 60px 40px;
    position: relative;
    overflow: hidden;
  }
  /* Mesh-style gradient overlay */
  .cover::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
      radial-gradient(ellipse 60% 50% at 20% 30%, rgba(26,115,232,0.22) 0%, transparent 70%),
      radial-gradient(ellipse 50% 60% at 75% 65%, rgba(13,124,62,0.16) 0%, transparent 70%),
      radial-gradient(ellipse 40% 40% at 55% 20%, rgba(45,27,105,0.18) 0%, transparent 70%),
      radial-gradient(ellipse 35% 45% at 85% 35%, rgba(255,146,43,0.08) 0%, transparent 60%);
    z-index: 0;
  }
  /* Particle dots layer */
  .cover::after {
    content: '';
    position: absolute;
    inset: 0;
    background:
      radial-gradient(2px 2px at 10% 15%, rgba(77,171,247,0.7), transparent),
      radial-gradient(2px 2px at 25% 80%, rgba(110,231,183,0.5), transparent),
      radial-gradient(1.5px 1.5px at 45% 10%, rgba(255,146,43,0.6), transparent),
      radial-gradient(2px 2px at 60% 70%, rgba(77,171,247,0.5), transparent),
      radial-gradient(1.5px 1.5px at 80% 25%, rgba(148,163,184,0.5), transparent),
      radial-gradient(2px 2px at 90% 85%, rgba(110,231,183,0.4), transparent),
      radial-gradient(1.5px 1.5px at 35% 45%, rgba(255,146,43,0.4), transparent),
      radial-gradient(2px 2px at 70% 40%, rgba(45,27,105,0.5), transparent),
      radial-gradient(1.5px 1.5px at 15% 55%, rgba(77,171,247,0.35), transparent),
      radial-gradient(2px 2px at 55% 90%, rgba(255,146,43,0.45), transparent);
    animation: particlePulse 6s ease-in-out infinite;
    z-index: 0;
  }

  /* Floating decorative shapes */
  .cover-shape {
    position: absolute;
    border-radius: 50%;
    z-index: 0;
    pointer-events: none;
  }
  .cover-shape.s1 {
    width: 350px; height: 350px;
    background: radial-gradient(circle, rgba(26,115,232,0.12) 0%, transparent 70%);
    top: -80px; left: -100px;
    animation: heroFloat1 18s ease-in-out infinite;
  }
  .cover-shape.s2 {
    width: 280px; height: 280px;
    background: radial-gradient(circle, rgba(13,124,62,0.10) 0%, transparent 70%);
    bottom: -60px; right: -80px;
    animation: heroFloat2 20s ease-in-out infinite;
  }
  .cover-shape.s3 {
    width: 200px; height: 200px;
    background: radial-gradient(circle, rgba(45,27,105,0.12) 0%, transparent 70%);
    top: 40%; right: 10%;
    animation: heroFloat3 16s ease-in-out infinite;
  }
  .cover-shape.s4 {
    width: 160px; height: 160px;
    background: radial-gradient(circle, rgba(255,146,43,0.08) 0%, transparent 70%);
    bottom: 20%; left: 8%;
    animation: heroFloat2 22s ease-in-out infinite;
  }

  .cover-content { position: relative; z-index: 1; display: flex; flex-direction: column; align-items: center; }

  .cover h1 {
    font-size: 44pt;
    font-weight: 900;
    line-height: 1.12;
    letter-spacing: 1.5px;
    margin-bottom: 14px;
  }
  .cover h1 .h2-word { color: #4dabf7; text-shadow: 0 0 30px rgba(77,171,247,0.4), 0 0 60px rgba(77,171,247,0.15); }
  .cover h1 .amp-word { color: #ffffff; }
  .cover h1 .propane-word { color: #ff922b; text-shadow: 0 0 30px rgba(255,146,43,0.35), 0 0 60px rgba(255,146,43,0.1); }

  .cover-subtitle {
    font-size: 11pt;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 4px;
    color: rgba(255,255,255,0.55);
    margin-bottom: 20px;
  }
  .cover-bar {
    width: 200px;
    height: 3px;
    border-radius: 3px;
    background: linear-gradient(90deg, #4dabf7 0%, #ff922b 50%, #0d7c3e 100%);
    margin-bottom: 48px;
    animation: barGrow 1.2s cubic-bezier(.23,1,.32,1) forwards;
    overflow: hidden;
  }


  /* Quick-nav links in hero */
  .cover-quicknav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px;
    margin-top: 28px;
  }
  .cover-quicknav a {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255,255,255,0.10);
    border: 1px solid rgba(255,255,255,0.20);
    border-radius: 8px;
    padding: 12px 24px;
    color: #fff;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 13px;
    font-weight: 600;
    text-decoration: none;
    transition: background 0.3s, box-shadow 0.3s;
  }
  .cover-quicknav a:hover {
    background: rgba(255,255,255,0.20);
    box-shadow: 0 4px 16px rgba(0,0,0,0.25);
  }
  .cover-quicknav a.qn-h2   { border-left: 3px solid #1a73e8; }
  .cover-quicknav a.qn-prop { border-left: 3px solid #e8710a; }
  .cover-quicknav a.qn-eng  { border-left: 3px solid #7b1fa2; }
  .cover-quicknav a.qn-strat{ border-left: 3px solid #0d7c3e; }
  @media(max-width:700px){
    .cover-quicknav { flex-direction: column; align-items: center; }
    .cover-quicknav a { width: 90%; justify-content: center; }
  }
  @media(min-width:701px) and (max-width:960px){
    .cover-quicknav { max-width: 520px; margin-left: auto; margin-right: auto; }
    .cover-quicknav a { flex: 1 1 calc(50% - 16px); justify-content: center; }
  }

  /* CONTAINER */
  .container { max-width: 1000px; margin: 0 auto; padding: 40px 50px; }

  /* TOC - Visual Cards */
  .toc {
    background: var(--bg);
    border-radius: 12px;
    padding: 32px 36px;
    margin-bottom: 40px;
  }
  .toc > h2 {
    font-size: 18pt;
    font-weight: 800;
    margin-bottom: 28px;
    color: var(--text);
    text-align: center;
  }
  .toc-part-banner {
    padding: 10px 20px;
    border-radius: 8px;
    font-size: 11pt;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin: 28px 0 14px 0;
    color: #fff;
  }
  .toc-part-banner:first-of-type { margin-top: 0; }
  .toc-part-banner.pa { background: #1a73e8; }
  .toc-part-banner.pb { background: #e8710a; }
  .toc-part-banner.pc { background: #7b1fa2; }
  .toc-part-banner.pd { background: #0d7c3e; }

  .toc-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 14px;
    margin-bottom: 10px;
  }
  @media (max-width: 900px) { .toc-grid { grid-template-columns: repeat(2, 1fr); } }
  @media (max-width: 540px) { .toc-grid { grid-template-columns: 1fr; } }

  .toc-card {
    display: block;
    text-decoration: none;
    color: inherit;
    background: #fff;
    border-radius: 10px;
    padding: 16px 16px 14px 20px;
    border: 1px solid var(--border);
    border-left: 5px solid #ccc;
    position: relative;
    overflow: hidden;
    transition: box-shadow .2s, transform .2s;
  }
  .toc-card:hover {
    box-shadow: 0 6px 20px rgba(0,0,0,.12);
    transform: translateY(-3px) scale(1.015);
  }
  .toc-card .card-num {
    position: absolute;
    top: 6px; right: 10px;
    font-size: 28pt;
    font-weight: 900;
    opacity: .08;
    line-height: 1;
    pointer-events: none;
  }
  .toc-card .card-emoji {
    font-size: 20pt;
    margin-bottom: 4px;
    line-height: 1.1;
  }
  .toc-card .card-title {
    font-size: 9.5pt;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 3px;
  }
  .toc-card .card-sub {
    font-size: 8pt;
    color: var(--text-secondary);
    line-height: 1.3;
  }
  /* Part colors on cards */
  .toc-card.pa { border-left-color: #1a73e8; background: #e8f0fe; }
  .toc-card.pa .card-num { color: #1a73e8; }
  .toc-card.pb { border-left-color: #e8710a; background: #fef3e8; }
  .toc-card.pb .card-num { color: #e8710a; }
  .toc-card.pc { border-left-color: #7b1fa2; background: #f3e8fe; }
  .toc-card.pc .card-num { color: #7b1fa2; }
  .toc-card.pd { border-left-color: #0d7c3e; background: #e8fef0; }
  .toc-card.pd .card-num { color: #0d7c3e; }

  @media print {
    .toc-card:hover { box-shadow: none; transform: none; }
    .toc-grid { grid-template-columns: repeat(3, 1fr); gap: 8px; }
    .toc-card { break-inside: avoid; }
  }

  /* SECTION HEADERS */
  .section-header {
    padding: 24px 32px;
    border-radius: 10px;
    margin: 40px 0 24px 0;
    position: relative;
  }
  .section-header.h2s {
    background: linear-gradient(135deg, var(--h2-dark), var(--h2-primary));
    color: white;
  }
  .section-header.props {
    background: linear-gradient(135deg, var(--propane-dark), var(--propane-primary));
    color: white;
  }
  .section-header.strats {
    background: linear-gradient(135deg, var(--strat-dark), var(--strat-primary));
    color: white;
  }
  .section-header.engs {
    background: linear-gradient(135deg, var(--eng-dark), var(--eng-primary));
    color: white;
  }
  .section-header.semis {
    background: linear-gradient(135deg, var(--semi-dark), var(--semi-primary));
    color: white;
  }
  .section-header .section-num {
    font-size: 9pt;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    opacity: 0.7;
  }
  .section-header h2 {
    font-size: 20pt;
    font-weight: 800;
    margin-top: 4px;
  }

  /* CONTENT */
  h3 {
    font-size: 14pt;
    font-weight: 700;
    margin: 28px 0 12px 0;
    color: var(--text);
    border-left: 4px solid var(--h2-primary);
    padding-left: 12px;
  }
  h3.prop-h { border-left-color: var(--propane-primary); }
  h3.strat-h { border-left-color: var(--strat-primary); }
  h3.eng-h { border-left-color: var(--eng-primary); }
  h3.semi-h { border-left-color: var(--semi-primary); }

  h4 {
    font-size: 11pt;
    font-weight: 600;
    margin: 20px 0 8px 0;
    color: var(--text);
  }

  p { margin-bottom: 10px; color: var(--text-secondary); }

  ul, ol { margin: 8px 0 12px 20px; color: var(--text-secondary); }
  li { margin-bottom: 4px; }

  /* TABLES */
  table {
    width: 100%;
    border-collapse: collapse;
    margin: 16px 0 20px 0;
    font-size: 8.5pt;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
  }
  thead th {
    background: #1e293b;
    color: white;
    padding: 10px 12px;
    text-align: left;
    font-weight: 600;
    font-size: 8pt;
    text-transform: uppercase;
    letter-spacing: 0.5px;
  }
  tbody td {
    padding: 8px 12px;
    border-bottom: 1px solid var(--border);
    vertical-align: top;
  }
  tbody tr:nth-child(even) { background: #f8fafc; }
  tbody tr:hover { background: #f1f5f9; }

  /* KPIS */
  .kpi-row {
    display: flex;
    gap: 16px;
    margin: 20px 0;
    flex-wrap: wrap;
  }
  .kpi {
    flex: 1;
    min-width: 140px;
    background: var(--bg);
    border-radius: 10px;
    padding: 16px 18px;
    text-align: center;
    border: 1px solid var(--border);
  }
  .kpi .val {
    font-size: 20pt;
    font-weight: 800;
    color: var(--h2-primary);
  }
  .kpi.prop-kpi .val { color: var(--propane-primary); }
  .kpi.strat-kpi .val { color: var(--strat-primary); }
  .kpi.semi-kpi .val { color: var(--semi-primary); }
  .kpi .lbl {
    font-size: 7.5pt;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--text-secondary);
    margin-top: 4px;
  }

  /* INFO BOXES */
  .info-box {
    background: var(--h2-light);
    border-left: 4px solid var(--h2-primary);
    border-radius: 0 8px 8px 0;
    padding: 14px 18px;
    margin: 14px 0;
    font-size: 9pt;
  }
  .info-box.prop-box {
    background: var(--propane-light);
    border-left-color: var(--propane-primary);
  }
  .info-box.eng-box {
    background: var(--eng-light);
    border-left-color: var(--eng-primary);
  }
  .info-box.strat-box {
    background: var(--strat-light);
    border-left-color: var(--strat-primary);
  }
  .info-box.semi-box {
    background: var(--semi-light);
    border-left-color: var(--semi-primary);
  }
  .info-box strong { color: var(--text); }

  /* FORMULA */
  .formula {
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px 20px;
    margin: 12px 0;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10pt;
    text-align: center;
    color: var(--eng-dark);
  }
  .formula .desc {
    font-family: 'Inter', sans-serif;
    font-size: 8pt;
    color: var(--text-secondary);
    margin-top: 6px;
    text-align: left;
  }

  /* STEPS */
  .step-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin: 14px 0;
  }
  .step-card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px 14px;
    font-size: 8.5pt;
  }
  .step-card .step-num {
    display: inline-block;
    background: var(--eng-primary);
    color: white;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    text-align: center;
    line-height: 22px;
    font-size: 8pt;
    font-weight: 700;
    margin-right: 6px;
  }
  .step-card .step-title { font-weight: 600; color: var(--text); }
  .step-card p { font-size: 8pt; margin-top: 4px; }

  /* COMPARISON BANNER */
  .comparison-banner {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin: 24px 0;
  }
  .comp-col {
    border-radius: 12px;
    padding: 20px 24px;
  }
  .comp-col.h2-col {
    background: linear-gradient(135deg, var(--h2-light), #dbeafe);
    border: 2px solid var(--h2-primary);
  }
  .comp-col.prop-col {
    background: linear-gradient(135deg, var(--propane-light), #fed7aa);
    border: 2px solid var(--propane-primary);
  }
  .comp-col h4 { font-size: 13pt; margin-bottom: 10px; }
  .comp-col.h2-col h4 { color: var(--h2-dark); }
  .comp-col.prop-col h4 { color: var(--propane-dark); }

  @media print {
    body { font-size: 9pt; }
    .container { padding: 20px 30px; }
    .cover { min-height: auto; padding: 80px 40px; }
    .kpi-row { gap: 10px; }
    .step-grid { grid-template-columns: 1fr; }
    table { font-size: 7.5pt; }
  }

/* ===== STICKY NAV HEADER ===== */


/* === PART PILLS (under each part banner) === */
.part-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 12px 20px;
  justify-content: center;
  border-radius: 0 0 10px 10px;
  margin-bottom: 24px;
}
.part-pills.pa-pills { background: rgba(26,115,232,0.12); }
.part-pills.pb-pills { background: rgba(232,113,10,0.12); }
.part-pills.pc-pills { background: rgba(123,31,162,0.12); }
.part-pills.pd-pills { background: rgba(13,124,62,0.12); }

.part-pill {
  display: inline-flex;
  align-items: center;
  border-radius: 20px;
  padding: 5px 14px;
  font-size: 12px;
  font-weight: 600;
  color: #fff;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background 0.2s, transform 0.2s;
}
.part-pill:hover { transform: scale(1.05); }
.part-pill strong { margin-right: 4px; }

.part-pill.pp-a { background: rgba(26,115,232,0.25); border: 1px solid rgba(26,115,232,0.4); }
.part-pill.pp-a:hover { background: rgba(26,115,232,0.45); }
.part-pill.pp-b { background: rgba(232,113,10,0.25); border: 1px solid rgba(232,113,10,0.4); }
.part-pill.pp-b:hover { background: rgba(232,113,10,0.45); }
.part-pill.pp-c { background: rgba(123,31,162,0.25); border: 1px solid rgba(123,31,162,0.4); }
.part-pill.pp-c:hover { background: rgba(123,31,162,0.45); }
.part-pill.pp-d { background: rgba(13,124,62,0.25); border: 1px solid rgba(13,124,62,0.4); }
.part-pill.pp-d:hover { background: rgba(13,124,62,0.45); }

@media print { .part-pills { display: none !important; } }


/* === ENHANCED KPI DASHBOARD === */
@keyframes kpiFadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.kpi-dashboard {
  width: 100%;
  max-width: 920px;
  margin-bottom: 44px;
}
.kpi-row-main {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 14px;
}
.kpi-row-secondary {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}
@media (max-width: 760px) {
  .kpi-row-main, .kpi-row-secondary { grid-template-columns: repeat(2, 1fr); }
}

/* Main KPI cards */
.kpi-card-main {
  background: linear-gradient(160deg, transparent 0%, rgba(77,171,247,0.15) 100%);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 16px;
  padding: 20px 24px;
  text-align: center;
  opacity: 0;
  animation: kpiFadeIn 0.7s ease forwards;
  transition: border-color 0.3s, box-shadow 0.3s;
}
.kpi-card-main:hover {
  border-color: rgba(255,255,255,0.35);
  box-shadow: 0 8px 24px rgba(0,0,0,0.25);
}
.kpi-card-main:nth-child(1) { animation-delay: 0.1s; }
.kpi-card-main:nth-child(2) { animation-delay: 0.2s; background: linear-gradient(160deg, transparent 0%, rgba(255,146,43,0.15) 100%); }
.kpi-card-main:nth-child(3) { animation-delay: 0.3s; background: linear-gradient(160deg, transparent 0%, rgba(123,31,162,0.15) 100%); }
.kpi-card-main:nth-child(4) { animation-delay: 0.4s; background: linear-gradient(160deg, transparent 0%, rgba(13,124,62,0.15) 100%); }

.kpi-card-main .kpi-icon { font-size: 28px; margin-bottom: 8px; }
.kpi-card-main .kpi-value { font-size: 36px; font-weight: 800; color: #fff; line-height: 1.1; }
.kpi-card-main .kpi-label { font-size: 12px; text-transform: uppercase; letter-spacing: 1px; color: rgba(255,255,255,0.6); margin-top: 6px; }
.kpi-card-main .kpi-sub { font-size: 11px; color: rgba(255,255,255,0.4); font-style: italic; margin-top: 4px; }

/* Secondary KPI pills */
.kpi-card-sec {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 12px;
  padding: 12px 16px;
  text-align: center;
  opacity: 0;
  animation: kpiFadeIn 0.6s ease forwards;
  transition: border-color 0.3s;
}
.kpi-card-sec:hover { border-color: rgba(255,255,255,0.25); }
.kpi-card-sec:nth-child(1) { animation-delay: 0.5s; }
.kpi-card-sec:nth-child(2) { animation-delay: 0.6s; }
.kpi-card-sec:nth-child(3) { animation-delay: 0.7s; }
.kpi-card-sec:nth-child(4) { animation-delay: 0.8s; }

.kpi-card-sec .kpi-icon-sm { font-size: 16px; }
.kpi-card-sec .kpi-val-sm { font-size: 20px; font-weight: 800; color: #fff; display: inline; margin: 0 4px; }
.kpi-card-sec .kpi-lbl-sm { font-size: 11px; color: rgba(255,255,255,0.55); margin-top: 2px; }

/* Print: static grid, no animations */
@media print {
  .kpi-card-main, .kpi-card-sec { opacity: 1 !important; animation: none !important; }
  .kpi-card-main { border: 1px solid #ccc; }
  .kpi-card-sec { border: 1px solid #ddd; }
  .kpi-card-main .kpi-value, .kpi-card-sec .kpi-val-sm { color: #222 !important; }
  .kpi-card-main .kpi-label, .kpi-card-sec .kpi-lbl-sm { color: #555 !important; }
  .kpi-card-main .kpi-sub { color: #777 !important; }
}