/* ============================================================
   PEPTIDE MAG — Guide Page Template v2
   Advanced layout: progress bar, sticky TOC, deep content
   ============================================================ */

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg-primary: #f8f9fb;
  --bg-secondary: #f0f2f5;
  --bg-card: #ffffff;
  --bg-card-hover: #f6f7f9;
  --bg-input: #f2f3f6;
  --accent: #2563eb;
  --accent-bright: #3b82f6;
  --accent-dim: rgba(37, 99, 235, 0.08);
  --accent-glow: rgba(37, 99, 235, 0.18);
  --text-primary: #1a1a1a;
  --text-secondary: #4a4a4a;
  --text-muted: #8a8a8a;
  --border: rgba(0, 0, 0, 0.08);
  --border-accent: rgba(37, 99, 235, 0.3);
  --glass-bg: rgba(250, 249, 247, 0.88);
  --glass-border: rgba(0, 0, 0, 0.06);
  --radius: 8px;
  --radius-lg: 16px;
  --font-display: 'Instrument Serif', Georgia, serif;
  --font-body: 'IBM Plex Sans', system-ui, sans-serif;
  --font-mono: 'IBM Plex Mono', monospace;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  opacity: 0.018;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 200px 200px;
}

a { color: var(--accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-bright); }

img { max-width: 100%; display: block; }

h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 400; line-height: 1.15; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem;
}

/* --- Reading Progress Bar --- */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-bright));
  z-index: 10001;
  transition: width 0.1s linear;
}

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 1rem 0;
  transition: background var(--transition), backdrop-filter var(--transition), box-shadow var(--transition);
}

.nav.scrolled {
  background: var(--glass-bg);
  backdrop-filter: blur(20px) saturate(1.2);
  -webkit-backdrop-filter: blur(20px) saturate(1.2);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  color: var(--text-primary);
}

.nav-logo-icon { width: 28px; height: 28px; color: var(--accent); }

.nav-logo-text {
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--text-secondary);
  letter-spacing: 0.04em;
  transition: color var(--transition);
  text-decoration: none;
}

.nav-links a:hover { color: var(--text-primary); }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 0.5rem;
}

/* --- Breadcrumb --- */
.breadcrumb {
  padding: 6.5rem 0 0;
}

.breadcrumb-inner {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.breadcrumb-inner a {
  color: var(--text-muted);
  transition: color var(--transition);
}

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

.breadcrumb-sep {
  color: var(--text-muted);
  opacity: 0.5;
  font-size: 0.7rem;
}

.breadcrumb-current {
  color: var(--text-secondary);
  font-weight: 500;
}

/* --- Guide Hero --- */
.guide-hero {
  padding: 2rem 0 3rem;
}

.guide-hero-content {
  max-width: 800px;
}

.guide-category-badge {
  display: inline-block;
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.3rem 0.85rem;
  border-radius: 100px;
  margin-bottom: 1.25rem;
}

.badge-weight-loss { background: rgba(37, 99, 235, 0.08); color: #2563eb; border: 1px solid rgba(37, 99, 235, 0.2); }
.badge-recovery { background: rgba(37, 99, 186, 0.08); color: #2563ba; border: 1px solid rgba(37, 99, 186, 0.2); }
.badge-anti-aging { background: rgba(190, 60, 120, 0.08); color: #be3c78; border: 1px solid rgba(190, 60, 120, 0.2); }
.badge-performance { background: rgba(124, 58, 237, 0.08); color: #7c3aed; border: 1px solid rgba(124, 58, 237, 0.2); }
.badge-nootropic { background: rgba(37, 99, 186, 0.08); color: #2563ba; border: 1px solid rgba(37, 99, 186, 0.2); }
.badge-sexual-health { background: rgba(124, 58, 237, 0.08); color: #7c3aed; border: 1px solid rgba(124, 58, 237, 0.2); }
.badge-longevity { background: rgba(190, 60, 120, 0.08); color: #be3c78; border: 1px solid rgba(190, 60, 120, 0.2); }
.badge-supplies { background: rgba(37, 99, 235, 0.08); color: #2563eb; border: 1px solid rgba(37, 99, 235, 0.2); }

.guide-title {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  line-height: 1.1;
}

.guide-tagline {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 640px;
}

/* --- Reading Time / Meta Bar --- */
.guide-meta {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-top: 1.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
}

.guide-meta-item {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.guide-meta-item svg {
  width: 14px;
  height: 14px;
  opacity: 0.6;
}

/* --- Main Layout: Sidebar + Content --- */
.guide-body {
  padding-bottom: 5rem;
}

.guide-layout {
  display: flex;
  gap: 3rem;
  align-items: flex-start;
}

.guide-content {
  flex: 1;
  min-width: 0;
  max-width: 800px;
}

/* --- Sticky TOC Sidebar --- */
.guide-toc {
  width: 240px;
  flex-shrink: 0;
  position: sticky;
  top: 90px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
}

.toc-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.toc-title {
  font-family: var(--font-body);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--accent);
}

.toc-list {
  list-style: none;
  padding: 0;
}

.toc-list li {
  margin-bottom: 0.15rem;
}

.toc-list a {
  display: block;
  font-size: 0.78rem;
  color: var(--text-muted);
  padding: 0.35rem 0.75rem;
  border-left: 2px solid transparent;
  border-radius: 0 4px 4px 0;
  transition: all var(--transition);
  text-decoration: none;
  line-height: 1.4;
}

.toc-list a:hover {
  color: var(--text-secondary);
  background: var(--accent-dim);
  border-left-color: rgba(37, 99, 235, 0.3);
}

.toc-list a.active {
  color: var(--accent);
  background: var(--accent-dim);
  border-left-color: var(--accent);
  font-weight: 500;
}

/* --- Quick Facts Card --- */
.quick-facts {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem 2.5rem;
  margin-bottom: 3rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.quick-facts-title {
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.5rem;
}

.quick-facts-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem 3rem;
}

.quick-fact {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.quick-fact-label {
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.quick-fact-value {
  font-size: 0.95rem;
  color: var(--text-primary);
  line-height: 1.5;
}

/* --- Product Image (overlapping quick-facts box) --- */
.quick-facts {
  position: relative;
  overflow: visible;
}

.product-image-float {
  position: absolute;
  right: -30px;
  top: -40px;
  width: 140px;
  text-align: center;
  z-index: 2;
  pointer-events: auto;
}

.product-vial-img {
  width: 140px;
  max-width: 140px;
  height: auto;
  display: block;
  filter: drop-shadow(0 10px 30px rgba(0, 0, 0, 0.15));
}

/* Shimmer overlay — sits on top of image, blend mode hides it on transparent pixels */
.product-image-float::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 60%;
  height: 100%;
  background: linear-gradient(
    105deg,
    transparent 30%,
    rgba(255, 255, 255, 0.4) 44%,
    rgba(255, 255, 255, 0.7) 50%,
    rgba(255, 255, 255, 0.4) 56%,
    transparent 70%
  );
  transform: skewX(-20deg);
  pointer-events: none;
  mix-blend-mode: overlay;
  opacity: 0;
  transition: none;
}

.product-image-float:hover::after {
  opacity: 1;
  left: 160%;
  transition: left 0.7s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.1s;
}

.product-image-source {
  display: inline-block;
  margin-top: 0.5rem;
  font-family: var(--font-body);
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition);
}

.product-image-source:hover {
  color: var(--accent);
}

@media (max-width: 768px) {
  .product-image-float {
    right: -10px;
    top: -30px;
    width: 110px;
  }
  .product-vial-img {
    width: 110px;
    max-width: 110px;
  }
}

@media (max-width: 480px) {
  .product-image-float {
    position: relative;
    right: auto;
    top: auto;
    width: 100px;
    margin: 0 auto 1rem;
  }
  .product-vial-img {
    width: 100px;
    max-width: 100px;
  }
}

/* --- Content Sections --- */
.guide-section {
  margin-bottom: 3rem;
  scroll-margin-top: 90px;
}

.guide-section-label {
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.guide-section h2 {
  font-size: 1.6rem;
  color: var(--text-primary);
  margin-bottom: 1.25rem;
}

.guide-section h3 {
  font-size: 1.2rem;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  margin-top: 1.5rem;
}

.guide-section p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 1rem;
}

.guide-section p:last-child {
  margin-bottom: 0;
}

.guide-section ul, .guide-section ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.guide-section li {
  font-size: 0.93rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 0.4rem;
}

/* --- Dosing Table --- */
.dosing-table-wrap {
  overflow-x: auto;
  margin-top: 1rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.dosing-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.dosing-table thead th {
  font-family: var(--font-body);
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #ffffff;
  background: var(--accent);
  text-align: left;
  padding: 0.85rem 1rem;
  white-space: nowrap;
}

.dosing-table thead th:first-child {
  border-radius: var(--radius) 0 0 0;
}

.dosing-table thead th:last-child {
  border-radius: 0 var(--radius) 0 0;
}

.dosing-table tbody td {
  padding: 0.85rem 1rem;
  color: var(--text-secondary);
  border-bottom: 1px solid rgba(0, 0, 0, 0.04);
  line-height: 1.5;
  vertical-align: top;
}

.dosing-table tbody tr:hover {
  background: var(--accent-dim);
}

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

/* --- Reconstitution Math Box --- */
.recon-box {
  background: var(--accent-dim);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 1.25rem 1.5rem;
  margin-top: 1rem;
}

.recon-box p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 0.5rem;
}

.recon-box p:last-child { margin-bottom: 0; }

.recon-box code {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
}

/* --- Reconstitution Steps --- */
.recon-steps {
  counter-reset: recon-step;
  list-style: none;
  padding: 0;
  margin-top: 1rem;
}

.recon-steps li {
  counter-increment: recon-step;
  position: relative;
  padding: 1rem 1rem 1rem 3.5rem;
  margin-bottom: 0.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.93rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.recon-steps li::before {
  content: counter(recon-step);
  position: absolute;
  left: 1rem;
  top: 1rem;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  color: #ffffff;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

/* --- Highlight Box (important notes, warnings) --- */
.highlight-box {
  background: var(--accent-dim);
  border: 1px solid rgba(37, 99, 235, 0.15);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  margin: 1.5rem 0;
}

.highlight-box-title {
  font-family: var(--font-body);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.highlight-box p, .highlight-box li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.highlight-box ul {
  padding-left: 1.25rem;
  margin: 0;
}

.highlight-box li {
  margin-bottom: 0.3rem;
}

/* --- Side Effects List --- */
.side-effects-list {
  list-style: none;
  padding: 0;
}

.side-effects-list li {
  position: relative;
  padding: 0.5rem 0 0.5rem 1.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.side-effects-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.95rem;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--border);
}

/* --- Injection Technique / Numbered Steps --- */
.technique-steps {
  counter-reset: technique-step;
  list-style: none;
  padding: 0;
}

.technique-steps li {
  counter-increment: technique-step;
  position: relative;
  padding: 0.75rem 0 0.75rem 2.5rem;
  font-size: 0.93rem;
  color: var(--text-secondary);
  line-height: 1.7;
  border-bottom: 1px solid rgba(0, 0, 0, 0.04);
}

.technique-steps li:last-child {
  border-bottom: none;
}

.technique-steps li::before {
  content: counter(technique-step);
  position: absolute;
  left: 0;
  top: 0.8rem;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 1.5px solid var(--accent);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

/* --- Storage Table --- */
.storage-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
  margin-top: 1rem;
}

.storage-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
}

.storage-item-label {
  font-family: var(--font-body);
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.35rem;
}

.storage-item-value {
  font-size: 0.92rem;
  color: var(--text-primary);
  line-height: 1.5;
}

.storage-item-note {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* --- Supplier Card --- */
.supplier-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem 2.5rem;
  margin-bottom: 3rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
  position: relative;
  overflow: hidden;
}

.supplier-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-bright));
}

.supplier-card-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}

.supplier-card-text {
  flex: 1;
}

.supplier-card-label {
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.supplier-card-text p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.supplier-features {
  list-style: none;
  padding: 0;
  margin: 0.75rem 0 0;
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.supplier-features li {
  font-size: 0.8rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.supplier-features li::before {
  content: '';
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
}

.supplier-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  padding: 0.8rem 1.8rem;
  background: var(--accent);
  color: #ffffff;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
  flex-shrink: 0;
}

.supplier-btn:hover {
  background: var(--accent-bright);
  color: #ffffff;
  transform: translateY(-1px);
  box-shadow: 0 8px 30px rgba(37, 99, 235, 0.2);
}

.supplier-btn svg { width: 14px; height: 14px; }

/* --- Related Peptides --- */
.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 1rem;
}

.related-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  transition: all var(--transition);
  text-decoration: none;
  display: block;
}

.related-card:hover {
  border-color: var(--border-accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.related-card-name {
  font-family: var(--font-display);
  font-size: 1.1rem;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.related-card-desc {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* --- References --- */
.references-list {
  list-style: none;
  padding: 0;
  counter-reset: ref-counter;
}

.references-list li {
  counter-increment: ref-counter;
  position: relative;
  padding: 0.85rem 1rem 0.85rem 2.5rem;
  margin-bottom: 0.5rem;
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.6;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}

.references-list li:hover {
  transform: translateX(2px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.references-list li::before {
  content: counter(ref-counter) '.';
  position: absolute;
  left: 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  font-weight: 500;
}

.references-list li em {
  color: var(--text-secondary);
}

.ref-link {
  display: inline-block;
  margin-left: 0.5rem;
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--accent);
  padding: 0.15rem 0.6rem;
  border: 1px solid var(--border-accent);
  border-radius: 100px;
  transition: all var(--transition);
  text-decoration: none;
  vertical-align: middle;
}

.ref-link:hover {
  background: var(--accent);
  color: #ffffff;
  border-color: var(--accent);
}

/* --- Back to Top --- */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  transform: translateY(10px);
  transition: all var(--transition);
  pointer-events: none;
  z-index: 100;
  color: var(--text-secondary);
}

.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.back-to-top:hover {
  background: var(--accent);
  color: #ffffff;
  border-color: var(--accent);
}

.back-to-top svg {
  width: 18px;
  height: 18px;
}

/* --- Footer --- */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 3rem 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer-left {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.footer-brand {
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-primary);
}

.footer-tagline {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.footer-links a {
  font-size: 0.8rem;
  color: var(--text-muted);
  transition: color var(--transition);
}

.footer-links a:hover { color: var(--text-secondary); }

.footer-social {
  display: flex;
  gap: 1rem;
}

.footer-social a {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  transition: all var(--transition);
}

.footer-social a:hover {
  border-color: var(--border-accent);
  color: var(--accent);
}

.footer-social svg { width: 16px; height: 16px; }

.footer-disclaimer {
  margin-top: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  font-size: 0.72rem;
  color: var(--text-muted);
  line-height: 1.7;
  text-align: center;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.footer-bottom {
  text-align: center;
  margin-top: 1.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .guide-toc {
    display: none;
  }

  .guide-layout {
    display: block;
  }
}

@media (max-width: 768px) {
  .container { padding: 0 1.25rem; }

  .nav-links { display: none; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--glass-border);
    gap: 1.25rem;
  }
  .nav-toggle { display: block; }

  .quick-facts-grid { grid-template-columns: 1fr; gap: 1rem; }
  .quick-facts { padding: 1.5rem; }

  .supplier-card-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .supplier-btn { width: 100%; justify-content: center; }

  .guide-title { font-size: clamp(1.8rem, 7vw, 2.8rem); }

  .dosing-table { font-size: 0.8rem; }
  .dosing-table thead th { padding: 0.6rem 0.6rem; font-size: 0.6rem; }
  .dosing-table tbody td { padding: 0.6rem; }

  .storage-grid { grid-template-columns: 1fr; }

  .related-grid { grid-template-columns: 1fr; }

  .guide-meta { flex-wrap: wrap; gap: 0.75rem; }

  .supplier-features { flex-direction: column; gap: 0.4rem; }

  .footer-inner { flex-direction: column; text-align: center; }
  .footer-links { justify-content: center; }
  .footer-social { justify-content: center; }
}

@media (max-width: 480px) {
  .breadcrumb-inner { font-size: 0.72rem; }
  .guide-hero { padding: 1.5rem 0 2rem; }
}