/* 官网顶栏（案例子系统共用，类名全部 cs-chrome-* 避免和子站 .nav 冲突） */
.cs-chrome {
  position: sticky;
  top: 0;
  z-index: 10050;
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", sans-serif;
  color: #111827;
}
.cs-chrome a { color: inherit; text-decoration: none; }
.cs-chrome-promo {
  height: 36px;
  line-height: 36px;
  padding: 0 16px;
  background: #0f2744;
  color: #fff;
  font-size: 13px;
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.cs-chrome-top {
  background: #fff;
  color: #111827;
  padding: 0;
  border-bottom: 1px solid #e5e7eb;
}
.cs-chrome-inner {
  width: min(1200px, calc(100% - 48px));
  margin: 0 auto;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 40px;
  position: relative;
}
.cs-chrome-brand { flex-shrink: 0; display: flex; align-items: center; }
.cs-chrome-brand img { height: 26px; width: auto; display: block; }
.cs-chrome-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 15px;
  font-weight: 500;
}
.cs-chrome-nav > a,
.cs-chrome-drop > span { color: #111827; cursor: pointer; }
.cs-chrome-drop { position: relative; padding: 24px 0; }
.cs-chrome-drop > span.on { color: #c8102e; font-weight: 700; }
.cs-chrome-mega {
  display: none;
  position: absolute;
  left: 0;
  top: 58px;
  width: min(920px, calc(100vw - 48px));
  background: #fff;
  border: 1px solid #e5e7eb;
  box-shadow: 0 16px 40px rgba(15, 23, 42, .12);
  padding: 22px 24px;
  grid-template-columns: repeat(4, minmax(160px, 1fr));
  gap: 8px 20px;
  z-index: 30;
}
.cs-chrome-drop:hover .cs-chrome-mega { display: grid; }
.cs-chrome-mega.prod {
  grid-template-columns: repeat(3, minmax(180px, 1fr));
  width: min(820px, calc(100vw - 48px));
}
.cs-chrome-mega.cases {
  grid-template-columns: minmax(220px, 1fr);
  width: min(520px, calc(100vw - 48px));
}
.cs-chrome-mega.sol {
  width: min(960px, calc(100vw - 48px));
  gap: 0;
  padding: 0;
  overflow: hidden;
}
.cs-chrome-col h5 {
  margin: 0 8px 6px;
  font-size: 12px;
  letter-spacing: .08em;
  color: #6b7280;
  font-weight: 600;
}
.cs-chrome-mega.prod h5 {
  color: #c8102e;
  font-size: 13px;
  letter-spacing: .04em;
  font-weight: 700;
}
.cs-chrome-mega a { display: block; padding: 10px 12px; border-radius: 8px; }
.cs-chrome-mega a:hover { background: #f8fafc; }
.cs-chrome-mega b { display: block; }
.cs-chrome-mega.prod b { color: #c8102e; font-size: 15px; font-weight: 700; }
.cs-chrome-mega small { color: #6b7280; display: block; margin-top: 4px; line-height: 1.45; }
.cs-chrome-mega.prod small { color: #2563eb; font-size: 12px; }
.cs-chrome-note {
  grid-column: 1 / -1;
  margin: 8px 8px 0;
  padding-top: 12px;
  border-top: 1px solid #e5e7eb;
  color: #6b7280;
  font-size: 12px;
  line-height: 1.65;
}
.cs-chrome-mega.sol .cs-chrome-col {
  padding: 22px 20px;
  border-right: 1px solid #e5e7eb;
}
.cs-chrome-mega.sol .cs-chrome-col:last-child {
  border-right: 0;
  background: #f8fafc;
}
.cs-chrome-mega.sol h5 { margin: 0 0 12px; }
.cs-chrome-mega.sol a { padding: 8px 0; border-radius: 0; }
.cs-chrome-mega.sol a:hover { background: transparent; }
.cs-chrome-mega.sol a:hover b { color: #c8102e; }
.cs-chrome-mega.sol a b { font-weight: 500; }
.cs-chrome-cta {
  margin-left: auto;
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: #c8102e;
  color: #fff !important;
  border-radius: 4px;
  padding: 10px 18px;
  font-size: 15px;
  font-weight: 500;
}
.cs-chrome-bang { display: none; }
.cs-chrome-phone { display: none; }
.cs-chrome-menu {
  display: none;
  height: 36px;
  padding: 0 12px;
  border: 1px solid #c8102e;
  background: #c8102e;
  color: #fff;
  border-radius: 4px;
  font: inherit;
  cursor: pointer;
}
@media (max-width: 900px) {
  .cs-chrome-inner { width: calc(100% - 24px); gap: 12px; }
  .cs-chrome-brand img { height: 22px; }
  .cs-chrome-cta { display: none; }
  .cs-chrome-bang {
    display: inline-flex;
    margin-left: auto;
    align-items: center;
    background: #0f2744;
    color: #fff !important;
    border-radius: 4px;
    padding: 8px 12px;
    font-size: 13px;
  }
  .cs-chrome-menu { display: inline-flex; align-items: center; }
  .cs-chrome-phone { display: inline-flex; }
  .cs-chrome-nav {
    display: none;
    margin-left: 0;
    position: absolute;
    left: 0; right: 0; top: 64px;
    background: #fff;
    border-bottom: 1px solid #e5e7eb;
    flex-direction: column;
    align-items: stretch;
    padding: 12px 20px 16px;
    gap: 12px;
    max-height: calc(100vh - 100px);
    overflow: auto;
  }
  .cs-chrome-nav.open { display: flex; }
  .cs-chrome-drop { padding: 8px 0; }
  .cs-chrome-mega {
    position: static;
    transform: none;
    width: auto;
    display: grid;
    box-shadow: none;
    border: 0;
    padding: 8px 0 0;
    grid-template-columns: 1fr 1fr;
  }
  .cs-chrome-mega.sol { padding: 8px 0 0; overflow: visible; }
  .cs-chrome-mega.sol .cs-chrome-col {
    border-right: 0;
    border-bottom: 1px solid #e5e7eb;
    padding: 12px 0;
    background: transparent;
  }
}