/*
  BK Kurumsal Web Sitesi — Düzen (Topbar, Header, Mobil Menü, Footer)
*/

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  background: var(--color-white);
  border-bottom: var(--border-width) solid var(--color-border);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-base), padding var(--transition-base);
}

.site-header.is-scrolled {
  box-shadow: var(--shadow-md);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
  min-height: var(--header-height);
  transition: min-height var(--transition-base);
}

.site-header.is-scrolled .site-header__inner {
  min-height: var(--header-height-scrolled);
}

/* Logo yer tutucu: gerçek logo eklendiğinde .brand içeriği bir <img> ile değiştirilebilir */
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-heading);
  font-weight: var(--fw-bold);
  color: var(--color-primary-strong);
  flex-shrink: 0;
  transition: opacity var(--transition-fast);
}

.brand:hover,
.brand:focus-visible {
  opacity: 0.85;
}

.brand__logo {
  display: block;
  height: 40px;
  width: auto;
}

.brand__logo--sm {
  height: 32px;
}

/* ---------- Ana Navigasyon (Masaüstü) ---------- */
.main-nav {
  display: none;
}

.main-nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.main-nav__link {
  position: relative;
  display: inline-block;
  font-size: var(--fs-small);
  font-weight: var(--fw-medium);
  color: var(--color-text);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-pill);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.main-nav__link:hover,
.main-nav__link:focus-visible {
  background: var(--color-orange-100);
  color: var(--color-primary-strong);
}

.main-nav__link.is-active {
  background: var(--color-ink-900);
  color: var(--color-white);
  font-weight: var(--fw-semibold);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.btn--header-cta {
  box-shadow: var(--shadow-sm);
}

@media (min-width: 1024px) {
  .main-nav {
    display: block;
  }
}

/* ---------- Mobil Menü Tetikleyici ---------- */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: transparent;
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius-pill);
  color: var(--color-primary-strong);
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  background: var(--color-orange-100);
  border-color: var(--color-orange-500);
}

.nav-toggle svg {
  width: 20px;
  height: 20px;
}

.nav-toggle .icon-close {
  display: none;
}

.nav-toggle[aria-expanded="true"] .icon-open {
  display: none;
}

.nav-toggle[aria-expanded="true"] .icon-close {
  display: block;
}

@media (min-width: 1024px) {
  .nav-toggle {
    display: none;
  }
}

/* ---------- Mobil Menü Panel ---------- */
.mobile-nav {
  position: fixed;
  inset: 0;
  z-index: var(--z-mobile-menu);
  background: var(--color-white);
  color: var(--color-text);
  transform: translateX(100%);
  transition: transform var(--transition-slow);
  overflow-y: auto;
}

.mobile-nav[data-open="true"] {
  transform: translateX(0);
}

.mobile-nav__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--container-padding);
  min-height: var(--header-height);
  border-bottom: var(--border-width) solid var(--color-border);
}

.mobile-nav__close {
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text);
}

.mobile-nav__close svg {
  width: 18px;
  height: 18px;
}

.mobile-nav__list {
  padding: var(--space-6) var(--container-padding);
  display: flex;
  flex-direction: column;
}

.mobile-nav__link {
  display: block;
  padding: var(--space-4) 0;
  font-family: var(--font-heading);
  font-size: 1.375rem;
  font-weight: var(--fw-semibold);
  color: var(--color-text);
  border-bottom: var(--border-width) solid var(--color-border);
}

.mobile-nav__link.is-active {
  color: var(--color-orange-600);
}

.mobile-nav__cta {
  margin-top: var(--space-6);
}

.mobile-nav__contacts {
  padding: 0 var(--container-padding) var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  font-size: var(--fs-small);
  color: var(--color-text-muted);
}

.mobile-nav__contacts a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
}

body.nav-open {
  overflow: hidden;
}

@media (min-width: 1024px) {
  .mobile-nav {
    display: none;
  }
}

/* ---------- Footer ---------- */
.site-footer {
  background: var(--color-ink-900);
  color: var(--color-text-on-dark-muted);
}

.site-footer a:hover,
.site-footer a:focus-visible {
  color: var(--color-orange-400);
}

.footer-top {
  padding-block: var(--space-10);
  border-bottom: var(--border-width) solid var(--color-border-on-dark);
}

.footer-grid {
  display: grid;
  gap: var(--space-8);
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  }
}

.footer-col__title {
  font-family: var(--font-heading);
  font-size: var(--fs-small);
  font-weight: var(--fw-semibold);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-white);
  margin-bottom: var(--space-4);
}

.footer-col p {
  color: var(--color-text-on-dark-muted);
  font-size: var(--fs-small);
}

.footer-col__list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  font-size: var(--fs-small);
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.footer-bottom {
  padding-block: var(--space-5);
}

.footer-bottom__inner {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  font-size: var(--fs-xsmall);
}

@media (min-width: 768px) {
  .footer-bottom__inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

.footer-legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}