/* ── Header ── */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: 68px;
  background: var(--bg-white);
  display: flex;
  align-items: center;
  transition: border-color 0.3s, backdrop-filter 0.3s;
  border-bottom: 1px solid transparent;
}

.site-header.scrolled {
  border-bottom-color: var(--border);
  backdrop-filter: blur(8px);
  background: rgba(255,255,255,0.94);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

/* ── Logo ── */

.header-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}

.header-logo .logo-bar {
  display: block;
  width: 4px;
  height: 32px;
  background: var(--yellow);
  border-radius: 2px;
  flex-shrink: 0;
}

.header-logo .logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1;
  gap: 3px;
}

.header-logo .logo-company {
  font-family: var(--font-ja);
  font-size: 10px;
  font-weight: 500;
  color: var(--text-secondary);
  letter-spacing: 0.08em;
  white-space: nowrap;
}

.header-logo .logo-site {
  font-family: var(--font-ja);
  font-size: 15px;
  font-weight: 700;
  color: var(--navy);
  letter-spacing: 0.03em;
  white-space: nowrap;
}

/* ── Nav ── */

.header-nav {
  display: flex;
  align-items: center;
  gap: 48px;
}

/* ナビリンク：アンダーライン 左→右 伸長 */
.header-nav a.nav-link {
  font-family: var(--font-ja);
  font-size: 16px;
  font-weight: 500;
  color: #0a0a0a;
  position: relative;
  padding-bottom: 3px;
  white-space: nowrap;
  transition: color 0.25s;
}

.header-nav a.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--navy);
  transition: width 0.28s var(--ease);
}

.header-nav a.nav-link:hover { color: var(--navy); }

.header-nav a.nav-link:hover::after { width: 100%; }

/* ナビCTAボタン */
.header-nav .btn-primary--nav {
  padding: 10px 20px;
  font-size: 12px;
  font-family: var(--font-ja);
  letter-spacing: 0.04em;
}

/* 「理念と文化」メガメニュー */

/* ラッパー */
.nav-mega-wrap {
  position: relative;
}

/* 矢印SVGアイコン */
.nav-link .nav-arrow {
  margin-left: 4px;
  vertical-align: middle;
  opacity: 0.6;
  transition: transform 0.25s var(--ease);
}

.nav-mega-wrap:hover .nav-arrow {
  transform: rotate(180deg);
}

/* nav-has-sub は汎用アンダーラインを無効化 */
.header-nav a.nav-link.nav-has-sub::after {
  display: none;
}

/* メガメニュー本体 */
.mega-menu {
  position: absolute;
  top: calc(100% + 16px);
  left: 50%;
  transform: translateX(-50%);
  min-width: 480px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: 0 12px 40px rgba(0,0,0,0.10);
  padding: 32px;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.25s var(--ease), transform 0.25s var(--ease);
  transform: translateX(-50%) translateY(8px);
}

/* ホバー時のブリッジ（メニューとリンク間のギャップを埋める） */
.mega-menu::before {
  content: '';
  position: absolute;
  top: -20px;
  left: 0;
  right: 0;
  height: 20px;
}

.nav-mega-wrap:hover .mega-menu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

/* メガメニュー内部レイアウト */
.mega-menu-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.mega-menu-col {
  padding: 16px;
  border-radius: 8px;
  transition: background 0.2s;
}

.mega-menu-col:hover {
  background: var(--bg-base);
}

.mega-menu-heading {
  font-family: var(--font-en);
  font-size: 13px;
  font-weight: 600;
  color: var(--yellow);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 4px;
}

.mega-menu-desc {
  font-family: var(--font-ja);
  font-size: 11px;
  color: var(--text-hint);
  margin-bottom: 10px;
}

.mega-menu-link {
  font-family: var(--font-ja);
  font-size: 14px;
  font-weight: 500;
  color: var(--navy);
  text-decoration: none;
  line-height: var(--leading-snug);
  display: block;
}

.mega-menu-link:hover {
  color: var(--yellow);
}

@media (max-width: 1200px) {
  .header-nav { gap: 28px; }
  .header-nav a.nav-link { font-size: 14px; }
  .header-nav .btn-primary--nav { padding: 8px 16px; font-size: 12px; }
}

@media (max-width: 1024px) {
  .header-nav { gap: 16px; }
  .header-nav a.nav-link { font-size: 13px; }
  .header-nav .btn-primary--nav { padding: 7px 12px; font-size: 12px; }
}

@media (max-width: 860px) {
  .header-nav .nav-link { display: none; }
  .nav-mega-wrap { display: none; }
}