/* ==========================================================================
   components/header.css  —  Site Header & Navigation
   ========================================================================== */

/* ── Header wrapper ───────────────────────────────────────────────────── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-sticky);
  height: var(--header-height);
  background-color: transparent;
  transition:
    background-color var(--transition-base),
    box-shadow var(--transition-base);
}

/* Scrolled state — added by main.js */
.site-header.is-scrolled {
  background-color: var(--color-white);
  box-shadow: var(--shadow-sm);
}

.site-header.is-scrolled .nav-link {
  color: var(--color-text);
}

.site-header.is-scrolled .logo-text {
  color: var(--color-brand-primary);
}

/* ── Nav Container ────────────────────────────────────────────────────── */
.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: var(--space-8);
}

/* ── Logo ─────────────────────────────────────────────────────────────── */
.nav-logo {
  text-decoration: none;
  flex-shrink: 0;
}

.logo-text {
  font-family: var(--font-serif);
  font-size: var(--text-md);
  font-weight: var(--font-weight-bold);
  color: var(--color-white);
  letter-spacing: -0.01em;
  transition: color var(--transition-fast);
}

/* ── Nav Menu ─────────────────────────────────────────────────────────── */
.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  list-style: none;
}

.nav-link {
  display: block;
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-base);
  font-weight: var(--font-weight-medium);
  color: rgba(255,255,255,0.9);
  border-radius: var(--radius-full);
  text-decoration: none;
  transition:
    color var(--transition-fast),
    background-color var(--transition-fast);
}

.nav-link:hover,
.nav-link.is-active {
  color: var(--color-white);
  background-color: rgba(255,255,255,0.12);
  text-decoration: none;
}

/* CTA Button in nav */
.nav-cta {
  background-color: var(--color-brand-accent);
  color: var(--color-white) !important;
  padding: var(--space-2) var(--space-6);
}

.nav-cta:hover {
  background-color: color-mix(in srgb, var(--color-brand-accent) 85%, black);
}

.site-header.is-scrolled .nav-link {
  color: var(--color-text);
}

.site-header.is-scrolled .nav-link:hover,
.site-header.is-scrolled .nav-link.is-active {
  color: var(--color-brand-primary);
  background-color: var(--color-gray-100);
}

/* ── Hamburger Toggle ─────────────────────────────────────────────────── */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: var(--space-2);
  background: none;
  border: none;
  cursor: pointer;
  z-index: var(--z-modal);
}

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

.site-header.is-scrolled .nav-toggle span {
  background-color: var(--color-text);
}

/* Open state — toggled by main.js */
.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ── Mobile ───────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
  :root { --header-height: var(--header-height-mobile); }

  .nav-toggle {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    inset: 0 0 0 30%;
    flex-direction: column;
    align-items: flex-start;
    padding: calc(var(--header-height-mobile) + var(--space-8)) var(--space-8);
    background-color: var(--color-white);
    box-shadow: var(--shadow-xl);
    transform: translateX(100%);
    transition: transform var(--transition-slow), visibility 0s var(--transition-slow);
    /* header(z-index:200)보다 낮게 → 토글 버튼이 항상 위에 노출됨 */
    z-index: 150;
    gap: var(--space-2);
    pointer-events: none;
    visibility: hidden;
  }

  .nav-menu.is-open {
    transform: translateX(0);
    pointer-events: auto;
    visibility: visible;
    transition: transform var(--transition-slow), visibility 0s 0s;
  }

  .nav-link {
    color: var(--color-text) !important;
    font-size: var(--text-md);
    width: 100%;
    padding: var(--space-3) var(--space-4);
  }

  .nav-cta {
    margin-top: var(--space-4);
    color: var(--color-white) !important;
  }

  /* Backdrop — header(200)보다 낮아야 토글 버튼 터치 가능 */
  .nav-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.35);
    z-index: 100;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-base);
  }

  .nav-backdrop.is-visible {
    opacity: 1;
    pointer-events: auto;
  }
}