/* =========================================================
   layout.css —— 容器、页眉页脚、栅格与断点
   ========================================================= */

.shell {
  inline-size: 100%;
  max-inline-size: var(--shell-max);
  margin-inline: auto;
  padding-inline: var(--shell-pad);
}

.section {
  padding-block: var(--space-2xl);
  position: relative;
}

.section > .shell { position: relative; z-index: 1; }

/* 区块标题组：眉标 + 主标 + 副说明 */
.section-head {
  display: grid;
  gap: var(--space-xs);
  margin-block-end: var(--space-xl);
  max-inline-size: 62ch;
}

.section-head--center {
  margin-inline: auto;
  text-align: center;
  justify-items: center;
}

.section-head--center .eyebrow { justify-content: center; }

.section-head__sub {
  color: var(--ink-600);
  font-size: var(--fs-lead);
  line-height: 1.8;
}

/* ---------- 页眉 ---------- */

.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: var(--z-header);
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(140%) blur(12px);
  border-block-end: 1px solid transparent;
  transition: border-color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}

.site-header.is-stuck {
  background: rgba(255, 255, 255, 0.96);
  border-block-end-color: var(--line-gold);
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  block-size: 84px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: clamp(0.6rem, 1.2vw, 1rem);
  flex: none;
}

.brand__mark {
  block-size: 30px;
  inline-size: auto;
}

/* 雙品牌並列：金色細線分隔，職趣雲標識稍小一號 */
.brand__divider {
  inline-size: 1px;
  block-size: 24px;
  background: var(--line-gold);
}

.brand__mark--partner { block-size: 26px; }

.site-nav { margin-inline-start: auto; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.4vw, 2.25rem);
  list-style: none;
}

.site-nav__list a {
  position: relative;
  display: inline-block;
  padding-block: 0.5rem;
  color: var(--ink-900);
  font-size: var(--fs-small);
  font-weight: 500;
  letter-spacing: 0.04em;
}

/* 当前区块高亮：金色下划线由左向右展开 */
.site-nav__list a::after {
  content: "";
  position: absolute;
  inset-inline-start: 0;
  inset-block-end: 0;
  block-size: 2px;
  inline-size: 100%;
  background: var(--grad-gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur) var(--ease);
}

.site-nav__list a:hover::after,
.site-nav__list a.is-current::after { transform: scaleX(1); }

.site-header__cta { flex: none; }

.nav-toggle {
  display: none;
  inline-size: 46px;
  block-size: 46px;
  padding: 12px;
  border: 1px solid var(--line-gold);
  border-radius: var(--radius-sm);
  background: transparent;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  block-size: 2px;
  inline-size: 100%;
  background: var(--ink-900);
  transition: transform var(--dur-fast) var(--ease), opacity var(--dur-fast) var(--ease);
}

.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); }

/* ---------- 页脚 ---------- */

.site-footer {
  background: var(--ink-900);
  color: rgba(255, 255, 255, 0.78);
  padding-block: var(--space-xl) var(--space-lg);
  border-block-start: 3px solid transparent;
  border-image: var(--grad-gold) 1;
}

.site-footer__inner {
  display: grid;
  gap: var(--space-lg);
  align-items: start;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
}

.site-footer__brands {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex-wrap: wrap;
}

.site-footer__brands img { block-size: 34px; inline-size: auto; }

.site-footer__divider {
  inline-size: 1px;
  block-size: 26px;
  background: rgba(255, 255, 255, 0.22);
}

.site-footer__nav { justify-self: end; }

.site-footer__nav ul {
  display: flex;
  gap: var(--space-md);
  list-style: none;
  flex-wrap: wrap;
}

.site-footer__nav a {
  color: rgba(255, 255, 255, 0.78);
  font-size: var(--fs-small);
}

.site-footer__nav a:hover { color: var(--gold-200); }

.site-footer__meta {
  grid-column: 1 / -1;
  padding-block-start: var(--space-md);
  border-block-start: 1px solid rgba(255, 255, 255, 0.12);
  font-family: var(--font-latin);
  font-size: var(--fs-small);
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.62);
}

/* ---------- 断点 ---------- */

@media (max-width: 1080px) {
  .site-nav__list { gap: 1.25rem; }
}

@media (max-width: 900px) {
  /* 双类名抬高性能度：否则 components.css 里较后的 .btn { display:inline-flex } 会盖掉隐藏规则 */
  .site-header__cta.btn { display: none; }
  .nav-toggle { display: flex; margin-inline-start: auto; }

  /* 抽屉是 header 的子元素：不用 backdrop-filter，避免它变成 fixed 后代的包含块；
     同时改为不透明纸白，否则正文从顶栏下方滚过时会有残影 */
  .site-header,
  .site-header.is-stuck {
    background: var(--paper-0);
    backdrop-filter: none;
  }

  .site-nav {
    position: fixed;
    inset: 0;
    z-index: var(--z-drawer);
    margin: 0;
    padding: 132px var(--shell-pad) var(--space-xl);
    background: var(--grad-panel);
    transform: translateY(-101%);
    transition: transform 420ms var(--ease);
    overflow-y: auto;
  }

  /* 同一层叠上下文内按 z-index 比较：logo 与关闭按钮要压在抽屉之上 */
  .brand,
  .nav-toggle { position: relative; z-index: calc(var(--z-drawer) + 1); }

  .site-nav.is-open { transform: translateY(0); }

  /* 抽屉展开时锁定页面滚动，避免背景与抽屉双重滚动 */
  html.nav-open { overflow: hidden; }

  /* 页眉融入金色抽屉，仅保留 logo 与关闭按钮 */
  html.nav-open .site-header {
    background: transparent;
    border-block-end-color: transparent;
  }

  html.nav-open .nav-toggle { border-color: rgba(20, 17, 12, 0.3); }

  /* 抽屉内文字压在金底上，统一用墨色（对比 6.9:1） */
  .site-nav__list {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-md);
  }

  .site-nav__list a {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--ink-900);
  }

  .site-nav__list a::after { background: var(--ink-900); }
}

@media (max-width: 720px) {
  .section { padding-block: var(--space-xl); }
  .site-footer__inner { grid-template-columns: 1fr; }
  .site-footer__nav { justify-self: start; }
}