/* ==========================================================================
   ZHIJIANG · LAYOUT V3
   工业样本目录式版式层：分区节奏、编号入口、分组导航、产品目录页。
   本文件仅补充与覆盖，不复制任何第三方站点样式。
   ========================================================================== */

:root {
  --v3-navy: #0d1f2d;
  --v3-steel: #164a6e;
  --v3-rule: #c6d5e2;
  --v3-muted: #52677a;
  --v3-panel: #ffffff;
}

/* ---------- 1. 导航：6 项主栏 + 产品分组 ---------- */
.nav {
  gap: 22px;
}

.nav > a {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.nav > a.nav-cta {
  font-weight: 650;
}

.nav-item-drop {
  position: relative;
  display: flex;
  align-items: center;
}

.nav-item-drop > summary {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-2);
  cursor: pointer;
  position: relative;
  transition: color 0.25s var(--ease);
}

.nav-item-drop > summary::-webkit-details-marker {
  display: none;
}

.nav-item-drop > summary::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1.5px;
  background: var(--amber);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.32s var(--ease);
}

.nav-item-drop > summary::after {
  content: "";
  width: 5px;
  height: 5px;
  margin-left: 1px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg) translate(-2px, -2px);
  transition: transform 0.25s var(--ease);
}

.nav-item-drop:hover > summary,
.nav-item-drop[open] > summary {
  color: var(--steel-700);
}

.nav-item-drop:hover > summary::before,
.nav-item-drop[open] > summary::before {
  transform: scaleX(1);
}

.nav-item-drop[open] > summary::after {
  transform: rotate(225deg) translate(-1px, -1px);
}

.nav-drop {
  position: absolute;
  top: calc(100% + 12px);
  left: -16px;
  z-index: 60;
  width: 322px;
  padding: 10px;
  background: var(--v3-panel);
  border: 1px solid var(--line);
  box-shadow: 0 24px 60px rgba(13, 40, 61, 0.14);
  display: grid;
  gap: 2px;
}

.nav-drop a {
  display: grid;
  gap: 3px;
  padding: 10px 12px;
  transition: background 0.2s var(--ease);
}

.nav-drop a:hover,
.nav-drop a:focus-visible {
  background: var(--ice);
}

.nav-drop strong {
  font-size: 13.5px;
  font-weight: 650;
  color: var(--ink);
  letter-spacing: 0.01em;
}

.nav-drop em {
  font-style: normal;
  font-size: 11.5px;
  line-height: 1.5;
  color: var(--v3-muted);
}

.nav-drop .nav-drop-all {
  margin-top: 4px;
  padding-top: 11px;
  border-top: 1px solid var(--line);
}

.nav-drop .nav-drop-all strong {
  color: var(--v3-steel);
}

/* ---------- 2. 首屏主张句 ---------- */
.hero-claim {
  max-width: 15em;
  margin-top: 20px;
  font-family: var(--font-display);
  font-size: clamp(1.95rem, 3.3vw, 2.8rem);
  line-height: 1.22;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--ink);
}

.hero-claim strong {
  font-weight: 800;
  color: var(--steel-700);
}

.hero-lede {
  margin-top: 14px;
  font-size: 14px;
  line-height: 1.8;
}

/* ---------- 3. 三段式入口条 ---------- */
.entry-strip {
  background: var(--v3-panel);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.entry-strip-inner {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.entry-link {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 24px 22px;
  border-right: 1px solid var(--line);
  transition: background 0.25s var(--ease);
}

.entry-link:first-child {
  padding-left: 0;
}

.entry-link:last-child {
  border-right: 0;
}

.entry-link:hover,
.entry-link:focus-visible {
  background: var(--paper);
}

.entry-no {
  flex: none;
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  color: var(--steel-600);
}

.entry-link h3 {
  margin: 0 0 5px;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--ink);
  transition: color 0.2s var(--ease);
}

.entry-link p {
  margin: 0;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--slate);
}

.entry-arrow {
  flex: none;
  margin-left: auto;
  padding-top: 2px;
  color: var(--steel-600);
}

.entry-arrow svg {
  width: 18px;
  height: 18px;
}

.entry-link:hover h3 {
  color: var(--steel-700);
}

/* ---------- 4. 内页页头 ---------- */
.page-intro {
  padding: 22px 0 46px;
  background: linear-gradient(180deg, #fbfcfd 0%, #eef4f9 100%);
  border-bottom: 1px solid var(--line);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-bottom: 30px;
  font-size: 11.5px;
  color: var(--steel-600);
}

.breadcrumb a:hover {
  color: var(--steel-700);
}

.page-intro h1 {
  margin: 10px 0 14px;
  font-size: clamp(2rem, 3.2vw, 2.8rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.page-intro .section-desc {
  max-width: 760px;
  font-size: 13.5px;
}

/* ---------- 5. 产品目录工具栏 ---------- */
.catalogue-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  padding: 20px 0 18px;
  border-bottom: 1px solid var(--line);
}

.filter-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
}

.filter-tabs button {
  height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  background: var(--v3-panel);
  font-size: 12.5px;
  font-weight: 600;
  color: var(--slate);
  transition: background 0.2s var(--ease), color 0.2s var(--ease),
              border-color 0.2s var(--ease);
}

.filter-tabs button:hover {
  border-color: var(--steel-300, #a9c4d8);
  color: var(--steel-700);
}

.filter-tabs button[aria-selected="true"],
.filter-tabs button.is-active {
  background: var(--steel-700);
  border-color: var(--steel-700);
  color: #fff;
}

.search-field {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 250px;
  min-height: 44px;
  padding-bottom: 4px;
  border-bottom: 1px solid var(--v3-rule);
}

.search-field svg {
  width: 16px;
  height: 16px;
  flex: none;
  color: var(--steel-600);
}

.search-field input {
  width: 100%;
  min-width: 0;
  padding: 6px 2px;
  border: 0;
  background: transparent;
  font-size: 13px;
  color: var(--ink);
}

.search-field input::placeholder {
  color: var(--v3-muted);
}

.results-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 0 4px;
  font-size: 11.5px;
  color: var(--steel-600);
}

.catalogue-grid {
  margin-top: 22px;
  row-gap: 40px;
}

.catalogue-note {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 40px;
  padding: 18px 22px;
  background: var(--paper);
  border: 1px solid var(--line);
}

.catalogue-note p {
  margin: 0;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--slate);
}

.note-icon {
  flex: none;
  width: 20px;
  height: 20px;
  border: 1px solid var(--v3-rule);
  border-radius: 50%;
  text-align: center;
  line-height: 18px;
  font-family: Georgia, serif;
  font-size: 11px;
  color: var(--v3-steel);
}

.empty-state {
  padding: 72px 20px;
  text-align: center;
  background: var(--paper);
  border: 1px solid var(--line);
}

.empty-state p {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 650;
  color: var(--ink);
}

.empty-state span {
  font-size: 12.5px;
  color: var(--slate);
}

.product-card.is-hidden {
  display: none;
}

.product-more {
  display: flex;
  margin-top: 22px;
}

.product-grid[hidden],
.empty-state[hidden] {
  display: none;
}

/* ---------- 6. 正文密度与标题权重 ---------- */
.section-desc {
  font-size: 13.5px;
  line-height: 1.8;
}

.product-body p:not(.product-code),
.product-card .product-body > p {
  font-size: 12.5px;
  line-height: 1.75;
}

.section-head h2,
.head-grid h2 {
  font-weight: 800;
  letter-spacing: -0.03em;
}

/* ---------- 7. 移动端 ---------- */
@media (max-width: 1230px) {
  .nav {
    gap: 14px;
  }

  .nav > a,
  .nav-item-drop > summary {
    font-size: 13px;
  }
}

@media (max-width: 1080px) {
  .nav-item-drop {
    display: block;
    width: 100%;
    border-bottom: 1px solid #eef4f9;
  }

  .nav-item-drop > summary {
    padding: 15px 2px;
    font-size: 15px;
    border-bottom: 0;
  }

  .nav-item-drop > summary::before {
    display: none;
  }

  .nav-drop {
    position: static;
    width: auto;
    padding: 0 0 10px 14px;
    background: transparent;
    border: 0;
    box-shadow: none;
  }

  .nav-drop a {
    padding: 9px 2px;
  }

  .nav-drop strong {
    font-size: 13px;
  }

  .nav-drop em {
    font-size: 11px;
  }

  .nav-drop .nav-drop-all {
    border-top: 0;
    padding-top: 9px;
  }

  .entry-strip-inner {
    grid-template-columns: 1fr;
  }

  .entry-link,
  .entry-link:first-child {
    padding: 20px 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .entry-link:last-child {
    border-bottom: 0;
  }

  .hero-claim {
    max-width: 18em;
  }

  .catalogue-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 720px) {
  .page-intro {
    padding: 18px 0 34px;
  }

  .breadcrumb {
    padding-bottom: 22px;
  }

  .catalogue-toolbar {
    align-items: stretch;
    flex-direction: column;
    gap: 16px;
  }

  .search-field {
    width: 100%;
    min-width: 0;
  }

  .catalogue-grid {
    grid-template-columns: 1fr;
    row-gap: 32px;
  }

  .hero-claim {
    font-size: clamp(1.75rem, 8vw, 2.2rem);
  }

  .entry-link h3 {
    font-size: 15.5px;
  }
}