/* ITB Promo — shared styles (mobile-first B2B) */
:root {
  --color-bg: #f7f8fa;
  --color-surface: #ffffff;
  --color-ink: #1a1f2e;
  --color-ink-muted: #4a5168;
  --color-border: #e2e5ee;
  --color-accent: #0b5fff;
  --color-accent-hover: #0847c7;
  --color-accent-soft: #e8f0ff;
  --color-trust: #0d6b4c;
  --color-footer: #12162a;
  --color-footer-muted: #a8b0c8;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(18, 22, 42, 0.06), 0 8px 24px rgba(18, 22, 42, 0.06);
  --max: 1100px;
  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --focus: 0 0 0 3px rgba(11, 95, 255, 0.35);
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--color-ink);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

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

a { color: var(--color-accent); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--color-accent-hover); }
a:focus-visible { outline: none; box-shadow: var(--focus); border-radius: 4px; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--color-accent);
  color: #fff;
  padding: 0.5rem 1rem;
  z-index: 100;
}
.skip-link:focus { left: 0.5rem; top: 0.5rem; }

.wrap {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

/* Header */
.site-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 50;
}
.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.25rem;
  padding: 0.75rem 0;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: var(--color-ink);
}
.brand:hover { color: var(--color-ink); }
.brand img {
  width: 44px;
  height: 44px;
  object-fit: contain;
  border-radius: 6px;
}
.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}
.brand-name { font-weight: 700; font-size: 1.05rem; letter-spacing: -0.01em; }
.brand-tag { font-size: 0.72rem; color: var(--color-ink-muted); font-weight: 500; }

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 0.45rem 0.7rem;
  font: inherit;
  cursor: pointer;
  color: var(--color-ink);
}
.nav-toggle:focus-visible { box-shadow: var(--focus); }

.site-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 1rem;
}
.site-nav a {
  color: var(--color-ink-muted);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  padding: 0.35rem 0;
}
.site-nav a:hover,
.site-nav a[aria-current="page"] { color: var(--color-accent); }

.header-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 0.75rem;
}
.header-phone {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-ink);
  text-decoration: none;
  white-space: nowrap;
}
.header-phone:hover { color: var(--color-accent); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.7rem 1.15rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  min-height: 44px;
  line-height: 1.2;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.btn:focus-visible { outline: none; box-shadow: var(--focus); }
.btn-primary {
  background: var(--color-accent);
  color: #fff;
}
.btn-primary:hover { background: var(--color-accent-hover); color: #fff; }
.btn-secondary {
  background: var(--color-surface);
  color: var(--color-accent);
  border-color: var(--color-accent);
}
.btn-secondary:hover { background: var(--color-accent-soft); color: var(--color-accent-hover); }
.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255,255,255,0.45);
}
.btn-ghost:hover { background: rgba(255,255,255,0.1); color: #fff; }
.btn-on-dark {
  background: #fff;
  color: var(--color-accent);
}
.btn-on-dark:hover { background: var(--color-accent-soft); color: var(--color-accent-hover); }

/* Hero */
.hero {
  background: linear-gradient(160deg, #0e1a3a 0%, #16306a 55%, #0b5fff 140%);
  color: #fff;
  padding: 3rem 0 3.25rem;
}
.hero h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.65rem, 4vw, 2.35rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  max-width: 18ch;
}
.hero-sub {
  margin: 0 0 1.5rem;
  font-size: 1.05rem;
  opacity: 0.92;
  max-width: 58ch;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
}
.hero-micro {
  margin: 0;
  font-size: 0.9rem;
  opacity: 0.8;
  max-width: 50ch;
}

/* Sections */
.section { padding: 3rem 0; }
.section-alt { background: var(--color-surface); border-block: 1px solid var(--color-border); }
.section h2 {
  margin: 0 0 0.5rem;
  font-size: clamp(1.35rem, 2.5vw, 1.7rem);
  letter-spacing: -0.015em;
}
.section-lead {
  margin: 0 0 1.75rem;
  color: var(--color-ink-muted);
  max-width: 60ch;
}

.page-hero {
  padding: 2.25rem 0 1.5rem;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}
.page-hero h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.5rem, 3vw, 2rem);
  letter-spacing: -0.02em;
  line-height: 1.25;
}
.page-hero .lead {
  margin: 0;
  color: var(--color-ink-muted);
  max-width: 65ch;
  font-size: 1.05rem;
}
.breadcrumb {
  margin: 0 0 0.75rem;
  font-size: 0.85rem;
  color: var(--color-ink-muted);
}
.breadcrumb a { color: var(--color-ink-muted); text-decoration: none; }
.breadcrumb a:hover { color: var(--color-accent); }
.breadcrumb span[aria-hidden] { margin: 0 0.35rem; }

/* Cards */
.card-grid {
  display: grid;
  gap: 1.1rem;
  grid-template-columns: 1fr;
}
@media (min-width: 640px) {
  .card-grid { grid-template-columns: 1fr 1fr; }
}
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.35rem 1.4rem;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}
.card h3 {
  margin: 0;
  font-size: 1.1rem;
  letter-spacing: -0.01em;
}
.card h3 a { color: var(--color-ink); text-decoration: none; }
.card h3 a:hover { color: var(--color-accent); }
.card p { margin: 0; color: var(--color-ink-muted); flex: 1; font-size: 0.95rem; }
.card-link {
  font-weight: 600;
  font-size: 0.92rem;
  text-decoration: none;
}
.card-link::after { content: " →"; }

/* Inquiry list */
.inquire-list {
  list-style: none;
  margin: 0 0 1.25rem;
  padding: 0;
  counter-reset: inquire;
  display: grid;
  gap: 0.65rem;
}
.inquire-list li {
  counter-increment: inquire;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 0.85rem 1rem 0.85rem 3rem;
  position: relative;
  font-weight: 500;
}
.inquire-list li::before {
  content: counter(inquire);
  position: absolute;
  left: 0.85rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.5rem;
  height: 1.5rem;
  border-radius: 50%;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  font-size: 0.8rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}
.inquire-note { color: var(--color-ink-muted); margin: 0 0 1.25rem; }
.inquire-close { margin: 0; font-weight: 500; }

/* Trust */
.trust-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.75rem;
}
.trust-list li {
  padding: 0.85rem 1rem;
  background: var(--color-bg);
  border-left: 3px solid var(--color-trust);
  border-radius: 0 8px 8px 0;
}
.trust-disclaimer {
  margin: 1.25rem 0 0;
  font-size: 0.92rem;
  color: var(--color-ink-muted);
  font-style: italic;
}

/* CTA band */
.cta-band {
  background: linear-gradient(120deg, #0b5fff, #16306a);
  color: #fff;
  padding: 2.5rem 0;
  text-align: center;
}
.cta-band h2 { margin: 0 0 0.5rem; color: #fff; }
.cta-band p { margin: 0 0 1.25rem; opacity: 0.92; }
.cta-band a.mailto-inline { color: #fff; font-weight: 700; }

/* Content pages */
.prose { max-width: 70ch; }
.prose h2 {
  margin: 2rem 0 0.65rem;
  font-size: 1.25rem;
}
.prose h2:first-child { margin-top: 0; }
.prose p { margin: 0 0 1rem; color: var(--color-ink-muted); }
.prose p strong, .prose li strong { color: var(--color-ink); }
.prose ul, .prose ol {
  margin: 0 0 1.25rem;
  padding-left: 1.25rem;
  color: var(--color-ink-muted);
}
.prose li { margin-bottom: 0.4rem; }
.prose .steps {
  list-style: none;
  padding: 0;
  counter-reset: step;
}
.prose .steps li {
  counter-increment: step;
  position: relative;
  padding: 0.75rem 0 0.75rem 2.75rem;
  border-bottom: 1px solid var(--color-border);
}
.prose .steps li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0.75rem;
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 50%;
  background: var(--color-accent);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}
.callout {
  background: var(--color-accent-soft);
  border: 1px solid #c5d8ff;
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  margin: 1.5rem 0;
}
.callout p { margin: 0; color: var(--color-ink); }
.callout a { font-weight: 600; }
.notice {
  background: #fff8e8;
  border: 1px solid #f0d9a0;
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  margin: 1.5rem 0;
}
.notice p { margin: 0; color: #5c4a1a; font-size: 0.95rem; }

.contact-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2rem;
  padding: 1.25rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  margin-top: 1.5rem;
}
.contact-strip dt {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  margin: 0 0 0.15rem;
  font-weight: 600;
}
.contact-strip dd { margin: 0; font-weight: 600; }
.contact-strip a { text-decoration: none; color: var(--color-ink); }
.contact-strip a:hover { color: var(--color-accent); }

/* Footer */
.site-footer {
  background: var(--color-footer);
  color: var(--color-footer-muted);
  padding: 2.5rem 0 1.75rem;
  margin-top: auto;
  font-size: 0.92rem;
}
.footer-grid {
  display: grid;
  gap: 1.75rem;
  margin-bottom: 1.75rem;
}
@media (min-width: 720px) {
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
}
.site-footer h2 {
  margin: 0 0 0.65rem;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #fff;
  font-weight: 600;
}
.site-footer .company-name {
  margin: 0 0 0.5rem;
  color: #fff;
  font-weight: 700;
  font-size: 1.05rem;
}
.site-footer p { margin: 0 0 0.5rem; }
.site-footer a { color: #c9d2ef; text-decoration: none; }
.site-footer a:hover { color: #fff; }
.footer-nav {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.4rem;
}
.footer-remind {
  margin: 0;
  font-size: 0.85rem;
  line-height: 1.5;
}
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 1.25rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.5rem;
  justify-content: space-between;
  align-items: center;
  font-size: 0.82rem;
}
.footer-petroleum {
  opacity: 0.75;
  font-size: 0.82rem;
}
.footer-petroleum a { color: var(--color-footer-muted); }
.footer-petroleum a:hover { color: #fff; }

/* Nav mobile */
@media (max-width: 880px) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    padding: 0.5rem 0 0.75rem;
    border-top: 1px solid var(--color-border);
  }
  .site-nav.is-open { display: flex; }
  .header-cta { width: 100%; }
  .header-cta .btn { flex: 1; }
}

@media (min-width: 881px) {
  .header-inner { flex-wrap: nowrap; }
  .site-nav { flex: 1; justify-content: center; }
}