/* =========================================================
   Fadhel Al-Ajmi & Partner — Engineering Consulting Bureau
   Base typography, layout primitives, section rhythm
   ========================================================= */

html { scroll-behavior: smooth; }

body {
  background: var(--color-bg);
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-body);
}

/* ---- Background technical texture: faint drafting grid ---- */
body {
  background-image:
    linear-gradient(90deg, rgba(22,33,43,0.035) 1px, transparent 1px),
    linear-gradient(rgba(22,33,43,0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  background-position: center top;
}

.container {
  width: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

section { position: relative; }

.section {
  padding-block: var(--space-2xl);
}
.section--tight { padding-block: var(--space-xl); }
.section--sunken { background: var(--color-surface-sunken); }
.section--dark {
  background: var(--color-ink);
  color: #EDEBE4;
}
.section--dark .eyebrow { color: var(--color-bronze); }

/* ---- Typography ---- */
h1, h2, h3, h4 { line-height: var(--lh-tight); letter-spacing: -0.01em; }
h1 { font-size: var(--fs-h1); font-weight: 700; }
h2 { font-size: var(--fs-h2); font-weight: 700; }
h3 { font-size: var(--fs-h3); font-weight: 700; }
h4 { font-size: var(--fs-h4); font-weight: 600; }

.display { font-size: var(--fs-display); font-weight: 700; line-height: 0.98; letter-spacing: -0.02em; }

.lead { font-size: var(--fs-lead); line-height: var(--lh-snug); color: var(--color-ink-soft); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  font-size: var(--fs-micro);
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}
.eyebrow::before {
  content: '';
  width: 22px;
  height: 1px;
  background: currentColor;
}

.section-head {
  max-width: 46rem;
  margin-bottom: var(--space-xl);
}
.section-head--center { margin-inline: auto; text-align: center; }

.text-muted { color: var(--color-ink-soft); }
.text-center { text-align: center; }

[dir="rtl"], .rtl { direction: rtl; font-family: var(--font-arabic); text-align: right; }

/* ---- Header ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(247, 246, 241, 0.9);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-line);
}
.site-header__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  height: 88px;
}

.wordmark {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}
.wordmark img {
  height: 56px;
  width: auto;
  display: block;
}

.main-nav { display: flex; align-items: center; gap: var(--space-lg); }
.main-nav__links { display: flex; gap: var(--space-md); }
.main-nav__links a {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--color-ink-soft);
  position: relative;
  padding-block: var(--space-2xs);
}
.main-nav__links a:hover, .main-nav__links a[aria-current="page"] { color: var(--color-ink); }
.main-nav__links a[aria-current="page"]::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -2px;
  height: 2px;
  background: var(--color-accent);
}

.nav-toggle { display: none; }

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2xs);
  padding: 0.85rem 1.6rem;
  font-size: 0.92rem;
  font-weight: 700;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--color-accent); color: #fff; }
.btn-primary:hover { background: var(--color-accent-dark); }
.btn-outline { border-color: var(--color-ink); color: var(--color-ink); }
.btn-outline:hover { background: var(--color-ink); color: #fff; }
.btn-ghost { color: var(--color-ink); }
.btn-ghost:hover { color: var(--color-accent); }
.btn-on-dark { border-color: rgba(237,235,228,0.4); color: #EDEBE4; }
.btn-on-dark:hover { background: #EDEBE4; color: var(--color-ink); border-color: #EDEBE4; }
.btn-sm { padding: 0.6rem 1.1rem; font-size: 0.82rem; }

.btn-row { display: flex; flex-wrap: wrap; gap: var(--space-sm); }

/* ---- Footer ---- */
.site-footer {
  background: var(--color-ink);
  color: #C9CDD1;
  padding-block: var(--space-xl) var(--space-lg);
}
.site-footer a { color: #C9CDD1; }
.site-footer a:hover { color: #fff; }
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: var(--space-lg);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-grid h4 { color: #fff; font-size: 0.85rem; letter-spacing: 0.06em; text-transform: uppercase; margin-bottom: var(--space-sm); }
.footer-grid ul li { margin-bottom: var(--space-2xs); font-size: 0.92rem; }
.footer-wordmark { color: #fff; font-weight: 700; margin-bottom: var(--space-2xs); }
.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
  padding-top: var(--space-lg);
  font-size: var(--fs-micro);
  color: #8892A0;
}

/* ---- Skip link ---- */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-ink);
  color: #fff;
  padding: 0.75rem 1.25rem;
  z-index: 1000;
}
.skip-link:focus { left: var(--space-sm); top: var(--space-sm); }

/* ---- Reveal on scroll ---- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
}
[data-reveal].is-visible { opacity: 1; transform: none; }

/* ---- Focus states ---- */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible, select:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}