/* ============================================================
   LAYOUT.CSS — Navigation, Footer, Page Grid
   ============================================================ */

/* ----------------------------------------------------------
   1. SITE HEADER / NAV
   ---------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-height);
  background: var(--navy);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  box-shadow: 0 2px 16px rgba(0,0,0,0.18);
}

.site-header .container {
  height: 100%;
  display: flex;
  align-items: center;
  gap: var(--sp-8);
}

/* Logo / site name */
.site-logo {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  text-decoration: none;
  flex-shrink: 0;
}

.site-logo__mark {
  width: 36px;
  height: 36px;
  background: var(--cambridge);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: white;
  letter-spacing: -0.02em;
}

.site-logo__text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.site-logo__name {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: white;
  letter-spacing: 0.01em;
}

.site-logo__sub {
  font-size: var(--text-xs);
  color: rgba(255,255,255,0.55);
  font-weight: 400;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* Main nav */
.main-nav {
  flex: 1;
}

.main-nav__list {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
}

.main-nav__link {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  font-weight: 500;
  color: rgba(255,255,255,0.75);
  text-decoration: none;
  transition: background var(--transition), color var(--transition);
  white-space: nowrap;
}

.main-nav__link:hover,
.main-nav__link.active {
  background: rgba(255,255,255,0.10);
  color: white;
}

/* Topic indicators in nav */
.main-nav__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.main-nav__dot--kq1     { background: var(--kq1); }
.main-nav__dot--kq2     { background: var(--kq2); }
.main-nav__dot--kq3     { background: var(--kq3); }
.main-nav__dot--germany { background: var(--germany); }

/* Nav right — future auth placeholder */
.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-left: auto;
}

/* STUB: login button — hidden until auth is implemented */
.btn-login {
  display: none; /* Remove this line when auth is added */
  padding: var(--sp-2) var(--sp-4);
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  font-weight: 500;
  color: white;
  cursor: pointer;
  transition: background var(--transition);
}

.btn-login:hover {
  background: rgba(255,255,255,0.2);
}

/* Mobile menu toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--sp-2);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: white;
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ----------------------------------------------------------
   2. BREADCRUMB
   ---------------------------------------------------------- */
.breadcrumb {
  padding: var(--sp-3) 0;
  border-bottom: 1px solid var(--border);
  background: var(--white);
}

.breadcrumb ol {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  flex-wrap: wrap;
}

.breadcrumb li {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  font-size: var(--text-sm);
  color: var(--text-muted);
}

.breadcrumb li:not(:last-child)::after {
  content: '›';
  color: var(--border-dark);
}

.breadcrumb a {
  color: var(--cambridge);
}

.breadcrumb li:last-child {
  color: var(--text);
  font-weight: 500;
}

/* ----------------------------------------------------------
   3. PAGE LAYOUTS
   ---------------------------------------------------------- */
.page-main {
  min-height: calc(100vh - var(--nav-height) - 80px);
  padding-bottom: var(--sp-20);
}

/* Hero — used on homepage and section hubs */
.page-hero {
  background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy) 50%, var(--navy-light) 100%);
  padding: var(--sp-16) 0 var(--sp-12);
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(ellipse at 80% 50%, rgba(46,84,150,0.4) 0%, transparent 60%),
    radial-gradient(ellipse at 20% 80%, rgba(28,47,94,0.6) 0%, transparent 50%);
}

.page-hero .container {
  position: relative;
  z-index: 1;
}

.page-hero__label {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: rgba(255,255,255,0.6);
  margin-bottom: var(--sp-4);
}

.page-hero__label-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.page-hero h1 {
  color: white;
  margin-bottom: var(--sp-5);
  text-shadow: 0 2px 12px rgba(0,0,0,0.2);
}

.page-hero__sub {
  font-size: var(--text-lg);
  color: rgba(255,255,255,0.75);
  max-width: 640px;
  line-height: 1.6;
  margin-bottom: var(--sp-8);
}

.page-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-4);
}

.page-hero__tag {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-1) var(--sp-3);
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: var(--radius-xl);
  font-size: var(--text-xs);
  font-weight: 500;
  color: rgba(255,255,255,0.8);
}

/* Content grid (used in content pages) */
.content-grid {
  display: grid;
  grid-template-columns: 1fr var(--sidebar-width);
  gap: var(--sp-8);
  align-items: start;
}

.content-sidebar {
  position: sticky;
  top: calc(var(--nav-height) + var(--sp-6));
}

/* Section layout */
.section {
  padding: var(--sp-12) 0;
}

.section + .section {
  border-top: 1px solid var(--border);
}

.section__header {
  margin-bottom: var(--sp-8);
}

.section__label {
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--cambridge);
  margin-bottom: var(--sp-2);
}

/* ----------------------------------------------------------
   4. TOPIC SECTION HEADER (coloured top stripe)
   ---------------------------------------------------------- */
.topic-header {
  padding: var(--sp-8) 0 var(--sp-6);
  border-bottom: 1px solid var(--border);
  margin-bottom: var(--sp-8);
  position: relative;
}

.topic-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
}

.topic-header--kq1::before     { background: var(--kq1); }
.topic-header--kq2::before     { background: var(--kq2); }
.topic-header--kq3::before     { background: var(--kq3); }
.topic-header--germany::before { background: var(--germany); }

/* ----------------------------------------------------------
   5. SITE FOOTER
   ---------------------------------------------------------- */
.site-footer {
  background: var(--navy-dark);
  color: rgba(255,255,255,0.6);
  padding: var(--sp-8) 0;
  margin-top: auto;
  border-top: 1px solid rgba(255,255,255,0.06);
}

.site-footer .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--sp-4);
}

.site-footer p {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.45);
  margin: 0;
}

.site-footer a {
  color: rgba(255,255,255,0.6);
  transition: color var(--transition);
}

.site-footer a:hover {
  color: white;
}

/* ----------------------------------------------------------
   6. RESPONSIVE — MOBILE NAV
   ---------------------------------------------------------- */
@media (max-width: 900px) {
  .main-nav {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--navy-dark);
    padding: var(--sp-4);
    border-bottom: 1px solid rgba(255,255,255,0.1);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition), opacity var(--transition);
    z-index: 99;
  }

  .main-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .main-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: var(--sp-1);
  }

  .main-nav__link {
    padding: var(--sp-3) var(--sp-4);
    font-size: var(--text-base);
  }

  .nav-toggle {
    display: flex;
  }

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

  .content-sidebar {
    position: static;
    order: -1;
  }
}

@media (max-width: 600px) {
  .container {
    padding-inline: var(--sp-4);
  }

  .page-hero {
    padding: var(--sp-10) 0 var(--sp-8);
  }

  .section {
    padding: var(--sp-8) 0;
  }
}