@charset "UTF-8";
/* ==========================================================================
   layout.css — 琨霖珠宝 · 全站框架层
   职责：顶部导航 / 页面头部 / 页脚 / 回到顶部
   说明：导航与页脚的 HTML 在每个页面内Hardcode（利于 SEO 与首屏渲染），
         修改时请按注释标记「全站统一」同步到其余页面。
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. 顶部导航
   结构：.site-header > .nav > [.nav__logo | .nav__menu | .nav__toggle]
   行为：滚动超过 60px 加 .is-stuck（加深底色与阴影）
   -------------------------------------------------------------------------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(247, 249, 248, .82);
  backdrop-filter: saturate(150%) blur(12px);
  -webkit-backdrop-filter: saturate(150%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: background .4s var(--ease), border-color .4s var(--ease), box-shadow .4s var(--ease);
}
.site-header.is-stuck {
  background: rgba(247, 249, 248, .96);
  border-bottom-color: var(--c-line-soft);
  box-shadow: 0 2px 20px rgba(62, 90, 84, .05);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  height: 76px;
}

/* —— 导航 LOGO：横版小尺寸 —— */
.nav__logo {
  flex: 0 0 auto;
  display: block;
  line-height: 0;
}
.nav__logo img,
.nav__logo svg {
  height: 38px;
  width: auto;
}
.nav__logo:hover { opacity: .78; }

/* —— 主菜单 —— */
.nav__menu {
  display: flex;
  align-items: center;
  gap: clamp(.75rem, 1.6vw, 1.6rem);
  margin: 0;
  padding: 0;
  list-style: none;
}
.nav__menu li { margin: 0; }
.nav__link {
  position: relative;
  display: block;
  padding: .5rem .15rem;
  font-family: var(--font-serif);
  font-size: .95rem;
  letter-spacing: .1em;
  color: var(--c-ink-soft);
  white-space: nowrap;
  transition: color .3s var(--ease);
}
/* 下划线：hover 展开，当前页常驻 */
.nav__link::after {
  content: "";
  position: absolute;
  left: 50%; bottom: 2px;
  width: 0; height: 1px;
  background: var(--c-gold);
  transform: translateX(-50%);
  transition: width .35s var(--ease);
}
.nav__link:hover { color: var(--c-ink); }
.nav__link:hover::after { width: 100%; }
.nav__link.is-active { color: var(--c-ink); }
.nav__link.is-active::after { width: 100%; }

/* —— 汉堡按钮（仅移动端显示） —— */
.nav__toggle {
  display: none;
  width: 44px; height: 44px;
  position: relative;
  flex: 0 0 auto;
}
.nav__toggle span {
  position: absolute;
  left: 11px;
  width: 22px; height: 1.5px;
  background: var(--c-ink);
  transition: transform .35s var(--ease), opacity .25s var(--ease);
}
.nav__toggle span:nth-child(1) { top: 16px; }
.nav__toggle span:nth-child(2) { top: 21.5px; }
.nav__toggle span:nth-child(3) { top: 27px; }
.nav__toggle.is-open span:nth-child(1) { top: 21.5px; transform: rotate(45deg); }
.nav__toggle.is-open span:nth-child(2) { opacity: 0; }
.nav__toggle.is-open span:nth-child(3) { top: 21.5px; transform: rotate(-45deg); }

/* —— 移动端侧滑面板 —— */
.nav__drawer {
  position: fixed;
  top: 0; right: 0;
  z-index: 99;
  width: min(78vw, 320px);
  height: 100dvh;
  padding: 6rem 2rem 2.5rem;
  background: var(--c-bg);
  border-left: 1px solid var(--c-line-soft);
  box-shadow: var(--shadow-lg);
  transform: translateX(100%);
  transition: transform .45s var(--ease);
  overflow-y: auto;
  display: none;
}
.nav__drawer.is-open { transform: none; }
.nav__drawer ul { list-style: none; margin: 0; padding: 0; }
.nav__drawer li { margin: 0; border-bottom: 1px solid var(--c-line-soft); }
.nav__drawer a {
  display: block;
  padding: 1.05rem .25rem;
  font-family: var(--font-serif);
  font-size: 1.05rem;
  letter-spacing: .12em;
  color: var(--c-ink);
}
.nav__drawer a.is-active { color: var(--c-gold-deep); }
.nav__drawer-foot {
  margin-top: 2.5rem;
  font-size: var(--fs-tiny);
  color: var(--c-ink-mute);
  line-height: 1.9;
}

/* 遮罩 */
.nav__mask {
  position: fixed;
  inset: 0;
  z-index: 98;
  background: rgba(62, 90, 84, .28);
  opacity: 0;
  visibility: hidden;
  transition: opacity .4s var(--ease), visibility .4s var(--ease);
}
.nav__mask.is-open { opacity: 1; visibility: visible; }

/* —— 导航响应式 —— */
@media (max-width: 1080px) {
  .nav__menu { display: none; }
  .nav__toggle { display: block; }
  .nav__drawer { display: block; }
}

/* --------------------------------------------------------------------------
   2. 页面头部（内页通用）
   结构：.page-head > .container > [面包屑 + h1 + 导语 + 装饰]
   -------------------------------------------------------------------------- */
.page-head {
  position: relative;
  margin-top: 76px;                       /* 让开固定导航 */
  padding-block: clamp(2.5rem, 5vw, 4.5rem);
  text-align: center;
  background:
    linear-gradient(180deg, var(--c-bg-soft), var(--c-bg));
  border-bottom: 1px solid var(--c-line-soft);
  overflow: hidden;
}
/* 右侧极淡的远山背景，作为标题区气质铺垫 */
.page-head::after {
  content: "";
  position: absolute;
  right: -4%; bottom: 0;
  width: 46%; height: 100%;
  background: url("../img/deco-mountain-wide.svg") right bottom / contain no-repeat;
  opacity: .35;
  pointer-events: none;
}
.page-head .container { position: relative; z-index: 1; }

.page-head__title {
  margin-bottom: .75rem;
  letter-spacing: .12em;
}
.page-head__en {
  display: block;
  margin-bottom: 1.25rem;
  font-size: var(--fs-en);
  letter-spacing: .34em;
  text-transform: uppercase;
  color: var(--c-ink-mute);
}
.page-head__lead {
  max-width: 44em;
  margin-inline: auto;
  color: var(--c-ink-soft);
  font-size: var(--fs-small);
  line-height: 2;
}

/* 面包屑 */
.crumb {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: .5rem;
  margin-bottom: 1.5rem;
  font-size: var(--fs-tiny);
  letter-spacing: .1em;
  color: var(--c-ink-mute);
}
.crumb a { color: var(--c-ink-mute); }
.crumb a:hover { color: var(--c-ink); }
.crumb span { opacity: .55; }

/* --------------------------------------------------------------------------
   3. 页脚
   -------------------------------------------------------------------------- */
.site-footer {
  position: relative;
  margin-top: var(--section-y);
  padding-block: clamp(3rem, 6vw, 4.5rem) 2rem;
  background: #334A45;                    /* 深青黛加沉一档，压住页面底部 */
  color: rgba(255, 255, 255, .72);
}
.site-footer a { color: rgba(255, 255, 255, .72); }
.site-footer a:hover { color: #D4C29A; }

.footer__top {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: clamp(1.75rem, 4vw, 3rem);
  padding-bottom: clamp(2rem, 4vw, 3rem);
  border-bottom: 1px solid rgba(255, 255, 255, .1);
}
@media (max-width: 900px) {
  .footer__top { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
  .footer__top { grid-template-columns: 1fr; gap: 2rem; }
}

/* 页脚 LOGO：简化单色版 */
.footer__logo {
  display: inline-block;
  margin-bottom: 1.1rem;
  line-height: 0;
}
.footer__logo img,
.footer__logo svg { height: 44px; width: auto; }

.footer__desc {
  max-width: 24em;
  font-size: var(--fs-tiny);
  line-height: 2;
  color: rgba(255, 255, 255, .58);
}

.footer__ttl {
  margin-bottom: 1.1rem;
  font-family: var(--font-serif);
  font-size: .95rem;
  font-weight: 500;
  letter-spacing: .16em;
  color: #fff;
}
.footer__list { list-style: none; margin: 0; padding: 0; }
.footer__list li { margin-bottom: .7rem; font-size: var(--fs-tiny); letter-spacing: .06em; }

.footer__contact li { line-height: 1.85; }
.footer__contact strong {
  display: block;
  font-weight: 500;
  font-size: var(--fs-small);
  color: #D4C29A;
  letter-spacing: .08em;
}

/* 页脚底部 */
.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.75rem;
  font-size: var(--fs-tiny);
  letter-spacing: .08em;
  color: rgba(255, 255, 255, .45);
}
.footer__note { max-width: 46em; line-height: 1.9; }

/* --------------------------------------------------------------------------
   4. 回到顶部
   -------------------------------------------------------------------------- */
.to-top {
  position: fixed;
  right: clamp(1rem, 3vw, 2.25rem);
  bottom: clamp(1rem, 3vw, 2.25rem);
  z-index: 90;
  width: 46px; height: 46px;
  display: grid;
  place-items: center;
  border: 1px solid var(--c-line);
  border-radius: 50%;
  background: rgba(255, 255, 255, .9);
  color: var(--c-ink);
  font-size: .9rem;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all .4s var(--ease);
}
.to-top.is-show { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--c-ink); color: #fff; border-color: var(--c-ink); }