/* ==============================
   Header / Global Navigation
   ============================== */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  padding: var(--sp-5) 0;
  transition: background .3s var(--ease), padding .3s var(--ease), box-shadow .3s var(--ease);
}
.site-header.is-scrolled {
  background: rgba(254, 253, 249, 0.92);
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  padding: var(--sp-4) 0;
  box-shadow: 0 1px 0 var(--c-line);
}
.site-header.is-on-dark { color: #fff; }

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-5);
  max-width: 1440px;
  padding-inline: var(--sp-7);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
}
.brand-mark { display: none; }
.brand-text { width: auto; height: 42px; }
.brand-text.alt { display: none; }
.site-header.is-on-dark .brand-text.default { display: none; }
.site-header.is-on-dark .brand-text.alt { display: block; }

/* タブレット */
@media (max-width: 767px) {
  .brand-text { height: 36px; }
}
/* モバイル */
@media (max-width: 480px) {
  .brand-text { height: 30px; }
}

/* Nav */
.gnav-list {
  display: flex;
  gap: var(--sp-6);
  align-items: center;
}
.gnav-list a {
  font-family: var(--ff-en);
  font-size: var(--fs-body);
  letter-spacing: var(--ls-en-nav);
  font-weight: 500;
  position: relative;
  padding: 6px 2px;
}
.gnav-list a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .35s var(--ease);
}
.gnav-list a:hover::after,
.gnav-list a[aria-current="page"]::after { transform: scaleX(1); }

/* PC専用: ナビを控えめに */
@media (min-width: 768px) {
  .gnav-list { gap: 36px; }
  .gnav-list a { font-size: var(--fs-nav); letter-spacing: var(--ls-en-label); font-weight: 600; color: var(--c-deep); }
}

/* Hamburger */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  position: relative;
  z-index: 110;
}
.nav-toggle span {
  position: absolute;
  left: 10px;
  right: 10px;
  height: 1.5px;
  background: currentColor;
  transition: transform .3s var(--ease), opacity .3s var(--ease), top .3s var(--ease);
}
.nav-toggle span:nth-child(1) { top: 16px; }
.nav-toggle span:nth-child(2) { top: 22px; }
.nav-toggle span:nth-child(3) { top: 28px; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { top: 22px; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { top: 22px; transform: rotate(-45deg); }

@media (max-width: 767px) {
  .header-inner { padding-inline: var(--sp-5); }
  .nav-toggle { display: block; }
  .gnav {
    position: fixed;
    inset: 0;
    background: var(--c-bg-white);
    color: var(--c-text);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity .3s var(--ease);
  }
  .gnav.is-open { opacity: 1; pointer-events: auto; }
  .gnav-list { flex-direction: column; gap: var(--sp-6); }
  .gnav-list a { font-size: var(--fs-body); }

  /* メニュー展開中はヘッダーのbackdrop-filterを無効化
     (fixed子孫の包含ブロックを奪われないようにするため) */
  .site-header:has(.gnav.is-open) {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
}

/* ==============================
   Buttons
   ============================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-4) var(--sp-6);
  border-radius: 999px;
  font-size: var(--fs-body);
  letter-spacing: var(--ls-en);
  font-weight: 500;
  position: relative;
  overflow: hidden;
  isolation: isolate;
  transition: transform .3s var(--ease), color .3s var(--ease), border-color .3s var(--ease);
}

/* E-1: 液体的塗りつぶし — ::before が左から滑り込む */
.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--btn-fill, var(--c-main));
  transform: translateX(-101%);
  transition: transform .45s cubic-bezier(0.25, 0.1, 0.25, 1);
  z-index: -1;
}

.btn .arrow {
  display: inline-block;
  transition: transform .3s var(--ease);
}

.btn-solid {
  background: var(--c-main);
  color: #fff;
  --btn-fill: var(--c-deep);
}

.btn-ghost {
  border: 1px solid rgba(255,255,255,0.55);
  color: #fff;
  --btn-fill: rgba(255,255,255,0.14);
}

.btn-outline {
  border: 1px solid var(--c-main);
  color: var(--c-main);
  --btn-fill: var(--c-main);
}

@media (hover: hover) {
  .btn:hover { transform: translateY(-2px); }
  .btn:hover::before { transform: translateX(0); }
  .btn-outline:hover { color: #fff; }
  .btn-ghost:hover { border-color: #fff; }
}

/* E-5: 矢印 nudge — ホバー1回につき1回だけ揺れて戻る */
@keyframes arrow-nudge {
  0%, 100% { transform: translateX(0); }
  50%      { transform: translateX(6px); }
}
@media (hover: hover) {
  .btn:hover .arrow,
  .text-link:hover .arrow {
    animation: arrow-nudge .6s ease;
  }
}

/* E-2: テキストリンクホバー — 下線が左から伸びる */
.text-link {
  position: relative;
  display: inline-block;
  transition: color .2s cubic-bezier(0.25, 0.1, 0.25, 1);
}
.text-link::after {
  content: "";
  position: absolute;
  left: 0; bottom: -2px;
  width: 100%; height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .3s cubic-bezier(0.25, 0.1, 0.25, 1);
}
@media (hover: hover) {
  .text-link:hover { color: var(--c-main); }
  .text-link:hover::after { transform: scaleX(1); }
}

/* ==============================
   A-1: Section divider (細い波線)
   ============================== */
.section-divider {
  width: 100%;
  height: 16px;
  background-image: url("../assets/wave-divider.svg");
  background-size: 1200px 16px;
  background-repeat: repeat-x;
  background-position: 0 50%;
  opacity: 0.18;
  pointer-events: none;
  animation: section-divider-drift 36s linear infinite;
}
@keyframes section-divider-drift {
  from { background-position-x: 0; }
  to   { background-position-x: -1200px; }
}

/* ==============================
   Footer
   ============================== */
.site-footer {
  background: var(--c-bg-beige-2);
  color: var(--c-text-sub);
  padding: var(--sp-7) 0 var(--sp-6);
  font-size: var(--fs-caption);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-6);
  justify-content: space-between;
  align-items: flex-start;
}
.footer-brand { display: flex; align-items: center; gap: var(--sp-3); color: var(--c-text); }
.footer-brand .brand-mark { height: 32px; width: auto; }
.footer-brand .brand-text { height: 22px; width: auto; }
@media (max-width: 767px) {
  .footer-brand .brand-mark { height: 28px; }
  .footer-brand .brand-text { height: 18px; }
}
.footer-links { display: flex; gap: var(--sp-6); flex-wrap: wrap; }
.footer-links a {
  font-family: var(--ff-en);
  font-size: var(--fs-caption);
  letter-spacing: var(--ls-en-nav);
  position: relative;
  display: inline-block;
  transition: color .2s cubic-bezier(0.25, 0.1, 0.25, 1);
}
.footer-links a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -2px;
  width: 100%; height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .3s cubic-bezier(0.25, 0.1, 0.25, 1);
}
@media (hover: hover) {
  .footer-links a:hover { color: var(--c-main); }
  .footer-links a:hover::after { transform: scaleX(1); }
}
.footer-bottom {
  margin-top: var(--sp-7);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--c-line);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--sp-3);
  font-size: var(--fs-caption);
  letter-spacing: var(--ls-jp);
}

/* ==============================
   Scroll cue (bouncing arrow)
   ============================== */
.scroll-cue {
  position: absolute;
  left: 50%;
  bottom: var(--sp-6);
  transform: translateX(-50%);
  font-family: var(--ff-en);
  font-size: var(--fs-caption);
  letter-spacing: var(--ls-en-label);
  color: var(--c-deep);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-2);
  opacity: 0.85;
}
.scroll-cue .arrow {
  width: 14px; height: 22px;
  display: inline-block;
  position: relative;
  animation: scrollBounce 2s var(--ease) infinite;
}
.scroll-cue .arrow::before,
.scroll-cue .arrow::after {
  content: "";
  position: absolute;
  background: currentColor;
}
.scroll-cue .arrow::before { left: 50%; top: 0; width: 1px; height: 100%; transform: translateX(-50%); }
.scroll-cue .arrow::after {
  left: 50%; bottom: 0;
  width: 8px; height: 8px;
  border-right: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
  background: transparent;
  transform: translateX(-50%) rotate(45deg);
}
@keyframes scrollBounce {
  0%, 100% { transform: translateY(0); opacity: 0.5; }
  50%      { transform: translateY(4px); opacity: 1; }
}