/* Shared header and course navigation for the four positive-society previews. */
html { scrollbar-gutter: stable; }
body { background: #f8f8f5; -webkit-font-smoothing: antialiased; }
.page-shell { width: min(calc(100% - 32px), 1120px); padding-top: 54px; padding-bottom: 72px; }
.pack-header { margin-bottom: 30px; }
.pack-brand {
  margin: 0 0 6px;
  color: #66625b;
  font-family: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  font-size: 14px;
  letter-spacing: 2px;
}
.pack-header h1 {
  font-family: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  font-size: clamp(22px, 4vw, 28px);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: 1px;
}
.corpus-nav-tabs {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 1fr);
  align-items: stretch;
  width: min(100%, 860px);
  max-width: none;
  margin: 0 auto 30px;
  overflow: hidden;
  border: 1px solid #e0e9e0;
  border-radius: 12px;
  background: #fffefa;
  box-shadow: 0 5px 18px rgba(47, 69, 58, .035);
}
.corpus-nav-tabs .tab-family {
  min-width: 0;
  padding: 0;
  border: 0;
  border-radius: 0;
  background: #f5f8f4;
}
.corpus-nav-tabs .tab-family-label {
  display: grid;
  place-items: center;
  height: 26px;
  padding: 3px 0 0;
  color: #69887a;
  font: 600 11px/1.4 -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  letter-spacing: .12em;
}
.corpus-nav-tabs .tab-family-links { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.corpus-nav-tabs .tab-family-links .main-tab + .main-tab { border-left: 1px solid #dfe9e1; }
.corpus-nav-tabs .main-tab {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 50px;
  margin: 0;
  padding: 7px 8px 10px;
  border: 0;
  color: #5d6961;
  background: transparent;
  font: 600 14px/1.4 -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}
.corpus-nav-tabs .main-tab:hover { background: rgba(85, 122, 112, .06); }
.corpus-nav-tabs .main-tab.is-active { color: #426d5e; background: #eaf2eb; }
.corpus-nav-tabs .main-tab.is-active::after {
  position: absolute;
  right: 16%;
  bottom: 0;
  left: 16%;
  height: 3px;
  border-radius: 3px 3px 0 0;
  background: #4e8067;
  content: "";
}
.corpus-nav-tabs .sample-tab {
  display: grid;
  grid-template-rows: 26px 50px;
  min-height: 76px;
  margin: 0;
  padding: 0;
  border-left: 1px solid #e0e9e0;
  background: #fffefa;
}
.corpus-nav-tabs .sample-tab::before {
  display: grid;
  place-items: center;
  align-self: stretch;
  padding-top: 3px;
  color: #888f88;
  font: 600 11px/1.4 -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  letter-spacing: .12em;
  content: "范文学习";
}
.corpus-nav-tabs .sample-tab.is-active::after { right: 16%; left: 16%; }
@media (max-width: 800px) {
  .page-shell { width: min(calc(100% - 20px), 1120px); padding-top: 34px; }
  .corpus-nav-tabs { margin-bottom: 23px; }
  .corpus-nav-tabs .main-tab { font-size: 12px; }
}