/* ============================================================
   AI 新手导航 · 索引页专属样式（index.html 使用）
   ============================================================ */

.index-hero {
  padding: 34px 28px 26px;
  border-radius: 20px;
  border: 1px solid var(--line);
  background:
    radial-gradient(120% 160% at 100% 0%, var(--accent-soft) 0%, transparent 55%),
    radial-gradient(120% 160% at 0% 0%, var(--brand-soft) 0%, transparent 52%),
    var(--panel);
  box-shadow: var(--shadow-sm);
  margin-bottom: 16px;
}
.index-hero h1 { font-size: 38px; margin: .1em 0 .3em; }
.index-hero .hero-sub { font-size: 19px; color: var(--ink-2); line-height: 1.85; margin: 0 0 18px; }
.index-hero .hero-note { font-size: 14.5px; color: var(--ink-3); margin-top: 14px; }

.quickstart { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); margin: 16px 0 26px; }
.qcard {
  display: block;
  padding: 15px 17px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  box-shadow: var(--shadow-sm);
  transition: transform .12s ease, border-color .12s ease;
}
.qcard:hover { text-decoration: none; transform: translateY(-2px); border-color: var(--brand); }
.qcard .q-icon { font-size: 22px; display: block; margin-bottom: 4px; }
.qcard .q-title { display: block; font-weight: 800; color: var(--ink); font-size: 16.5px; }
.qcard .q-desc { display: block; font-size: 14px; color: var(--ink-3); line-height: 1.7; margin-top: 2px; }

.toolbar {
  position: sticky;
  top: 57px;
  z-index: 30;
  padding: 12px 14px;
  margin: 0 0 8px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: color-mix(in srgb, var(--panel) 92%, transparent);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
}
.search-row { display: flex; gap: 10px; align-items: center; }
.search-row input {
  flex: 1;
  min-width: 0;
  font: inherit;
  font-size: 16px;
  padding: 10px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--panel-2);
  color: var(--ink);
}
.search-row input:focus { outline: 2px solid var(--brand); outline-offset: 1px; }
.search-row .hint { font-size: 13px; color: var(--ink-3); white-space: nowrap; }

.chips { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 10px; }
.chip {
  font: inherit;
  font-size: 14px;
  font-weight: 700;
  padding: 5px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--ink-2);
  cursor: pointer;
}
.chip:hover { border-color: var(--brand); color: var(--brand); }
.chip.active { background: var(--brand); border-color: var(--brand); color: #fff; }

.cat-section { margin: 34px 0 0; scroll-margin-top: 130px; }
.cat-head { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; border-bottom: 2px solid var(--line); padding-bottom: 8px; }
.cat-head h2 { border: 0; padding: 0; margin: 0; font-size: 24px; }
.cat-head .cat-icon { font-size: 24px; }
.cat-head .cat-count { font-size: 13.5px; color: var(--ink-3); font-weight: 700; }
.cat-intro { color: var(--ink-2); font-size: 16px; margin: 8px 0 16px; }

.cards { display: grid; gap: 13px; grid-template-columns: repeat(auto-fill, minmax(272px, 1fr)); }
.icard {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 15px 17px 13px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  box-shadow: var(--shadow-sm);
  transition: transform .12s ease, border-color .12s ease, box-shadow .12s ease;
}
.icard:hover {
  text-decoration: none;
  transform: translateY(-2px);
  border-color: var(--brand);
  box-shadow: var(--shadow);
}
.icard .ic-icon { font-size: 21px; line-height: 1.2; }
.icard .ic-title { font-weight: 800; font-size: 16.5px; color: var(--ink); line-height: 1.55; }
.icard .ic-blurb { font-size: 14.5px; color: var(--ink-2); line-height: 1.75; }
.icard .ic-tags { margin-top: auto; padding-top: 8px; }
.icard .tag { font-size: 11.5px; padding: 1px 9px; margin: 0 5px 0 0; }

.icard .ic-index {
  float: right;
  font-size: 12px;
  font-weight: 800;
  color: var(--ink-3);
  font-family: var(--mono);
}

.hidden { display: none !important; }
.noresult {
  display: none;
  padding: 26px 20px;
  text-align: center;
  color: var(--ink-3);
  border: 1px dashed var(--line);
  border-radius: 14px;
  margin: 24px 0;
}
.noresult.show { display: block; }

.howto { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); margin: 16px 0 6px; }
.howto > div { border: 1px solid var(--line); border-radius: 14px; padding: 15px 17px; background: var(--panel-2); }
.howto h4 { margin: 0 0 5px; font-size: 16px; }
.howto p { margin: .2em 0; font-size: 15px; color: var(--ink-2); }

.site-foot { margin-top: 46px; padding-top: 20px; border-top: 1px solid var(--line); font-size: 14.5px; color: var(--ink-3); line-height: 1.9; }
.site-foot .meta { display: flex; flex-wrap: wrap; gap: 6px 18px; margin-bottom: 8px; }

@media (prefers-color-scheme: dark) {
  .toolbar { background: rgba(27, 30, 39, .92); }
}
@media (max-width: 640px) {
  .index-hero { padding: 24px 19px 20px; }
  .index-hero h1 { font-size: 29px; }
  .toolbar { top: 0; }
  .cards { grid-template-columns: 1fr; }
}
@media print {
  .toolbar, .quickstart { display: none !important; }
  .cards { grid-template-columns: repeat(2, 1fr); }
}