/* Header (scoped) */
:root {
  --itt-primary: #ff6f3d; /* vibrant accent */
  --itt-secondary: #ffd166; /* playful highlight */
  --itt-text: #1b1e28;
  --itt-bg: #ffffff;
  --focus-ring: 0 0 0 3px rgba(255,111,61,.35), 0 0 0 6px rgba(255,209,102,.25);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--itt-bg);
  color: var(--itt-text);
  border-bottom: 3px solid rgba(255,111,61,0.1);
  box-shadow: 0 2px 10px rgba(0,0,0,.04);
}

.site-header .header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1rem;
}

/* Skip link */
.site-header .skip-link {
  position: absolute;
  left: -9999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
.site-header .skip-link:focus {
  left: 1rem;
  top: 0.5rem;
  width: auto;
  height: auto;
  padding: 0.5rem 0.75rem;
  background: #111;
  color: #fff;
  border-radius: 6px;
  outline: none;
  box-shadow: var(--focus-ring);
  z-index: 1001;
}

/* Branding */
.site-header .brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: "Poppins", system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-weight: 700;
  letter-spacing: 0.2px;
  color: var(--itt-text);
  text-decoration: none;
}
.site-header .brand:focus-visible { box-shadow: var(--focus-ring); border-radius: 8px; }
.site-header .brand-mark {
  width: 28px; height: 28px; border-radius: 8px;
  background: linear-gradient(135deg, var(--itt-primary), var(--itt-secondary));
  box-shadow: 0 4px 10px rgba(255,111,61,.3);
}
.site-header .brand-text { font-size: 1.15rem; }

/* Nav */
.site-header .primary-nav { /* default visible for no-JS */ }
.site-header .nav-list {
  display: flex;
  gap: 0.25rem;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
}
.site-header .nav-link {
  display: inline-block;
  padding: 0.5rem 0.75rem;
  border-radius: 8px;
  text-decoration: none;
  color: var(--itt-text);
  font-family: "Inter", system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-weight: 500;
}
.site-header .nav-link:hover {
  background: rgba(255,111,61,0.08);
}
.site-header .nav-link:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* Toggle */
.site-header .nav-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  background: transparent;
  border: 2px solid rgba(27,30,40,0.1);
  color: var(--itt-text);
  padding: 0.4rem 0.6rem;
  border-radius: 10px;
  cursor: pointer;
}
.site-header .nav-toggle:focus-visible { outline: none; box-shadow: var(--focus-ring); }
.site-header .nav-toggle .hamburger { display: inline-flex; flex-direction: column; gap: 4px; }
.site-header .nav-toggle .hamburger span { width: 20px; height: 2px; background: var(--itt-text); border-radius: 2px; transition: transform .25s ease, opacity .2s ease; }

/* Mobile behavior activated only when JS is present */
@media (max-width: 960px) {
  .js .site-header .nav-toggle { display: inline-flex; }
  .js .site-header .primary-nav { display: none; }
  .js .site-header .primary-nav.is-open { display: block; }

  .site-header .primary-nav {
    position: absolute;
    top: 100%;
    left: 0; right: 0;
    background: var(--itt-bg);
    border-bottom: 3px solid rgba(255,111,61,0.1);
    box-shadow: 0 8px 20px rgba(0,0,0,.06);
  }
  .site-header .nav-list { flex-direction: column; align-items: stretch; gap: 0; }
  .site-header .nav-link { padding: 0.9rem 1rem; border-radius: 0; }
  .site-header .nav-link:hover { background: rgba(255,209,102,0.15); }

  /* Toggle animation when expanded */
  .site-header .nav-toggle[aria-expanded="true"] .hamburger span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
  .site-header .nav-toggle[aria-expanded="true"] .hamburger span:nth-child(2) { opacity: 0; }
  .site-header .nav-toggle[aria-expanded="true"] .hamburger span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }
}

@media (prefers-reduced-motion: reduce) {
  .site-header *, .site-header *::before, .site-header *::after { transition: none !important; animation: none !important; }
}