/* ============================================================
   VERTEXHUB BLOG — Shared Stylesheet
   Design tokens match index.html exactly
============================================================ */

:root {
  --brand:           #0471A6;
  --brand-dark:      #035b8a;
  --brand-green:     #00BD4C;
  --brand-green-dark:#00a040;
  --brand-gradient:  linear-gradient(135deg, #0471A6 0%, #00BD4C 100%);
  --brand-glow:      rgba(4, 113, 166, 0.28);
  --brand-glass:     rgba(4, 113, 166, 0.10);
  --brand-glass-border: rgba(4, 113, 166, 0.32);
  --brand-green-glass:  rgba(0, 189, 76, 0.10);
  --brand-green-border: rgba(0, 189, 76, 0.28);

  --bg-base:         #070d1c;
  --bg-surface:      #0b1220;
  --bg-elevated:     #0f1829;

  --glass-bg:         rgba(255, 255, 255, 0.05);
  --glass-bg-hover:   rgba(255, 255, 255, 0.09);
  --glass-border:     rgba(255, 255, 255, 0.09);
  --glass-border-strong: rgba(255, 255, 255, 0.16);
  --glass-blur:       blur(18px);
  --glass-blur-sm:    blur(10px);

  --text-primary:   #edf2ff;
  --text-secondary: rgba(210, 225, 255, 0.65);
  --text-muted:     rgba(175, 195, 230, 0.42);

  --success: #22c55e;
  --error:   #f87171;

  --font-body:    'Inter', system-ui, -apple-system, sans-serif;
  --font-display: 'Manrope', 'Inter', sans-serif;

  --space-1: 0.25rem;  --space-2: 0.5rem;
  --space-3: 0.75rem;  --space-4: 1rem;
  --space-5: 1.25rem;  --space-6: 1.5rem;
  --space-8: 2rem;     --space-10: 2.5rem;
  --space-12: 3rem;    --space-16: 4rem;
  --space-20: 5rem;    --space-24: 6rem;

  --max-width:  1100px;
  --nav-height: 70px;

  --radius-md:   12px;
  --radius-lg:   18px;
  --radius-xl:   24px;
  --radius-full: 9999px;

  --shadow-card: 0 8px 32px rgba(0,0,0,0.45), inset 0 1px 0 rgba(255,255,255,0.05);
  --shadow-nav:  0 4px 24px rgba(0,0,0,0.55);
  --shadow-btn:  0 4px 20px var(--brand-glow), inset 0 1px 0 rgba(255,255,255,0.15);

  --transition-fast: 150ms ease;
  --transition-base: 260ms ease;
}

/* ============================================================
   RESET
============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img  { max-width: 100%; height: auto; display: block; }
a    { color: inherit; text-decoration: none; }
ul   { list-style: none; }
button { cursor: pointer; border: none; background: none; font: inherit; }

/* ============================================================
   AMBIENT BACKGROUND BLOBS
============================================================ */
body::before, body::after {
  content: '';
  position: fixed;
  border-radius: 50%;
  filter: blur(130px);
  pointer-events: none;
  z-index: 0;
}
body::before {
  width: 650px; height: 650px;
  background: radial-gradient(circle, rgba(4,113,166,0.11) 0%, transparent 70%);
  top: -120px; right: -80px;
}
body::after {
  width: 550px; height: 550px;
  background: radial-gradient(circle, rgba(0,189,76,0.08) 0%, transparent 70%);
  bottom: 15%; left: -100px;
}

/* ============================================================
   LAYOUT
============================================================ */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
  position: relative;
  z-index: 1;
}
.container--article {
  width: 100%;
  max-width: 760px;
  margin-inline: auto;
  padding-inline: var(--space-6);
  position: relative;
  z-index: 1;
}

/* ============================================================
   TYPOGRAPHY
============================================================ */
h1 {
  font-family: var(--font-display);
  font-size: clamp(1.875rem, 4.5vw, 3rem);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}
h2 {
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--text-primary);
}
h3 { font-size: 1.0625rem; font-weight: 700; line-height: 1.35; color: var(--text-primary); }
p  { color: var(--text-secondary); line-height: 1.7; }
.eyebrow {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--brand-green);
}

/* ============================================================
   GLASS UTILITIES
============================================================ */
.glass {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-card);
}

/* ============================================================
   BUTTONS
============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.75rem 1.625rem;
  border-radius: var(--radius-md);
  font-size: 0.9375rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  border: 1.5px solid transparent;
  transition: all var(--transition-base);
  white-space: nowrap;
  cursor: pointer;
}
.btn-primary {
  background: var(--brand-gradient);
  color: #fff;
  border-color: transparent;
  box-shadow: var(--shadow-btn);
}
.btn-primary:hover {
  filter: brightness(1.12);
  transform: translateY(-2px);
}
.btn-large { padding: 0.9375rem 2rem; font-size: 1rem; }

/* ============================================================
   HEADER / NAV  (identical to index.html)
============================================================ */
#site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  z-index: 1000;
  transition: all var(--transition-base);
}
#site-header.scrolled {
  background: rgba(7, 13, 28, 0.88);
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: var(--shadow-nav);
}
.nav-container {
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo-img {
  height: 32px;
  width: auto;
  display: block;
  filter: brightness(0) invert(1);
  opacity: 0.92;
  transition: opacity var(--transition-fast);
}
.nav-logo-img:hover { opacity: 1; }
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}
.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}
.nav-links a:hover,
.nav-links a.active { color: var(--text-primary); }
.nav-cta-link {
  background: var(--brand-gradient) !important;
  color: #fff !important;
  padding: 0.5rem 1.125rem !important;
  border-radius: var(--radius-full) !important;
  font-weight: 600 !important;
  font-size: 0.875rem !important;
  box-shadow: 0 2px 14px var(--brand-glow);
  transition: all var(--transition-fast) !important;
}
.nav-cta-link:hover {
  filter: brightness(1.1) !important;
  transform: translateY(-1px);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
}
.nav-toggle span {
  display: block;
  width: 22px; height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}
.nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   FOOTER  (identical to index.html)
============================================================ */
#site-footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--glass-border);
  padding-block: var(--space-16) var(--space-10);
}
.footer-layout {
  display: flex;
  justify-content: space-between;
  gap: var(--space-12);
  flex-wrap: wrap;
}
.footer-logo-img {
  height: 30px;
  width: auto;
  filter: brightness(0) invert(1);
  opacity: 0.70;
  margin-bottom: var(--space-4);
}
.footer-brand p {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: var(--space-2);
  max-width: 260px;
  line-height: 1.6;
}
.footer-brand a { font-size: 0.875rem; color: var(--brand-green); font-weight: 500; }
.footer-nav { display: flex; flex-direction: column; gap: var(--space-3); }
.footer-nav a { font-size: 0.875rem; color: var(--text-muted); transition: color var(--transition-fast); }
.footer-nav a:hover { color: var(--text-primary); }
.footer-bottom {
  border-top: 1px solid var(--glass-border);
  margin-top: var(--space-8);
  padding-top: var(--space-6);
}
.footer-bottom p { font-size: 0.8rem; color: var(--text-muted); }

/* ============================================================
   BLOG INDEX — Post grid
============================================================ */
.blog-hero {
  padding-top: calc(var(--nav-height) + var(--space-16));
  padding-bottom: var(--space-12);
}
.blog-hero h1 { margin-bottom: var(--space-4); }
.blog-hero p  { font-size: 1.0625rem; max-width: 520px; }

.post-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-6);
  padding-bottom: var(--space-20);
}
.post-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  transition: border-color var(--transition-fast), transform var(--transition-base);
}
.post-card:hover {
  border-color: var(--brand-glass-border);
  transform: translateY(-3px);
}
.post-card .post-tag {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--brand-green);
}
.post-card h2 {
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1.35;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  margin: 0;
}
.post-card .post-excerpt {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  flex: 1;
}
.post-card .post-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
}
.post-card .post-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--brand-green);
  transition: gap var(--transition-fast);
}
.post-card:hover .post-link { gap: var(--space-3); }

/* ============================================================
   ARTICLE LAYOUT
============================================================ */
.article-page { padding-top: calc(var(--nav-height) + var(--space-16)); }

.article-hero { padding-bottom: var(--space-10); }
.article-hero h1 { margin-bottom: var(--space-5); }
.article-meta {
  display: flex;
  gap: var(--space-5);
  font-size: 0.8125rem;
  color: var(--text-muted);
  flex-wrap: wrap;
  margin-top: var(--space-4);
}

.article-body { padding-bottom: var(--space-20); }
.article-body h2 { margin: var(--space-10) 0 var(--space-4); }
.article-body h3 { margin: var(--space-6) 0 var(--space-3); }
.article-body p  { margin-bottom: var(--space-5); }
.article-body strong { color: var(--text-primary); }
.article-body ul,
.article-body ol {
  color: var(--text-secondary);
  padding-left: var(--space-6);
  margin-bottom: var(--space-5);
}
.article-body li { margin-bottom: var(--space-2); }

/* Callout box */
.callout {
  background: var(--brand-glass);
  border: 1px solid var(--brand-glass-border);
  border-left: 3px solid var(--brand-green);
  border-radius: var(--radius-md);
  padding: var(--space-5) var(--space-6);
  margin: var(--space-8) 0;
}
.callout p { margin: 0; font-size: 0.9375rem; }

/* Stat row */
.stat-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
  margin: var(--space-8) 0;
}
.stat-card {
  background: var(--bg-elevated);
  border: 1px solid rgba(4,113,166,0.2);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  text-align: center;
}
.stat-card .num {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 900;
  color: var(--brand-green);
  line-height: 1;
  margin-bottom: var(--space-2);
}
.stat-card .label { font-size: 0.8125rem; color: var(--text-muted); line-height: 1.4; }

/* Calc / comparison tables */
.calc-table, .compare-table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-6) 0;
  font-size: 0.9rem;
}
.calc-table th, .compare-table th {
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-weight: 700;
  padding: var(--space-3) var(--space-4);
  text-align: left;
  border-bottom: 1px solid rgba(4,113,166,0.25);
  font-size: 0.8125rem;
}
.calc-table td, .compare-table td {
  padding: var(--space-3) var(--space-4);
  color: var(--text-secondary);
  border-bottom: 1px solid rgba(255,255,255,0.05);
  vertical-align: top;
}
.calc-table tr:last-child td {
  color: var(--text-primary);
  font-weight: 700;
  border-bottom: none;
  background: rgba(0,189,76,0.08);
}
.compare-table .yes   { color: var(--brand-green); font-weight: 700; }
.compare-table .no    { color: rgba(248,113,113,0.85); font-weight: 700; }
.compare-table .partial { color: rgba(251,191,36,0.85); font-weight: 700; }
.compare-table .highlight-col { background: rgba(0,189,76,0.06); }

/* Steps list */
.steps-list { list-style: none; padding: 0; margin: var(--space-6) 0 var(--space-8); }
.steps-list li {
  display: flex;
  gap: var(--space-4);
  margin-bottom: var(--space-5);
  color: var(--text-secondary);
}
.step-num {
  flex-shrink: 0;
  width: 2rem; height: 2rem;
  border-radius: 50%;
  background: var(--brand-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.8125rem;
  color: #fff;
}
.step-content strong { color: var(--text-primary); display: block; margin-bottom: var(--space-2); }

/* Before / after grid */
.before-after {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
  margin: var(--space-6) 0;
}
.ba-card { background: var(--bg-elevated); border-radius: var(--radius-lg); padding: var(--space-5); }
.ba-card .ba-label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: var(--space-3);
}
.ba-card.before .ba-label { color: rgba(248,113,113,0.85); }
.ba-card.after  .ba-label { color: var(--brand-green); }
.ba-card ul { color: var(--text-secondary); padding-left: var(--space-5); font-size: 0.9375rem; }
.ba-card li { margin-bottom: var(--space-2); }

/* Trade grid */
.trade-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-4);
  margin: var(--space-6) 0;
}
.trade-card {
  background: var(--bg-elevated);
  border: 1px solid rgba(4,113,166,0.2);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}
.trade-card .trade-name { font-weight: 700; color: var(--text-primary); margin-bottom: var(--space-2); font-size: 1rem; }
.trade-card .trade-detail { color: var(--text-secondary); font-size: 0.875rem; line-height: 1.5; }
.trade-card .trade-cost  { color: var(--brand-green); font-weight: 700; margin-top: var(--space-3); font-size: 0.9375rem; }

/* FAQ section */
.faq-section { margin-top: var(--space-12); }
.faq-section > h2 { margin-top: 0; }
.faq-item { border-bottom: 1px solid rgba(255,255,255,0.07); padding: var(--space-5) 0; }
.faq-item:last-child { border-bottom: none; }
.faq-q { font-weight: 700; color: var(--text-primary); margin-bottom: var(--space-3); font-size: 1rem; }
.faq-a { color: var(--text-secondary); font-size: 0.9375rem; margin: 0; }

/* CTA block */
.cta-block {
  background: linear-gradient(135deg, rgba(4,113,166,0.15) 0%, rgba(0,189,76,0.10) 100%);
  border: 1px solid var(--brand-glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-12) var(--space-8);
  text-align: center;
  margin: var(--space-12) 0;
}
.cta-block h2 { margin-bottom: var(--space-4); }
.cta-block p  { max-width: 480px; margin-inline: auto; margin-bottom: var(--space-6); }
.cta-note { margin-top: var(--space-4); font-size: 0.8125rem; color: var(--text-muted); }
.cta-note a { color: var(--brand-green); }

/* ============================================================
   RESPONSIVE
============================================================ */
@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0; right: 0;
    background: rgba(7, 13, 28, 0.97);
    backdrop-filter: blur(22px);
    -webkit-backdrop-filter: blur(22px);
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-6);
    gap: var(--space-5);
    border-bottom: 1px solid var(--glass-border);
    box-shadow: var(--shadow-nav);
  }
  .nav-links.nav-open { display: flex; }
  .stat-row { grid-template-columns: 1fr 1fr; }
  .before-after { grid-template-columns: 1fr; }
  .post-grid { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .cta-block { padding: var(--space-8) var(--space-5); }
  .footer-layout { flex-direction: column; gap: var(--space-8); }
  .compare-table { font-size: 0.75rem; }
  .compare-table th, .compare-table td { padding: var(--space-2) var(--space-3); }
}