/* 理见 · 全站顶栏与模型搜索：首页和各模型页共用 */
:root {
  --bar-h: 44px;
  --site-card: #0c111b;
  --site-line: #2a3446;
  --site-line-soft: #1f2735;
}

/* 顶栏：吸顶，logo 回首页 +「全部模型」+ 可展开的搜索 */
.site-bar { position: sticky; top: 0; z-index: 20; height: var(--bar-h);
  background: rgba(10,14,22,.92); -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--site-line-soft); }
.site-bar-in { position: relative; display: flex; align-items: center; gap: 10px; height: 100%; padding: 0 16px; }
.site-logo { display: flex; align-items: center; gap: 8px; margin-right: auto; color: #e6ebf2; text-decoration: none; white-space: nowrap; }
.site-logo svg { width: 22px; height: 22px; color: #ffc94a; }
.site-logo b { font-size: 16px; letter-spacing: 2px; }
.site-logo span { padding-left: 8px; border-left: 1px solid var(--site-line); font: 12px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  color: #8d99ab; letter-spacing: .5px; }
.site-all, .site-find { display: inline-flex; align-items: center; gap: 6px; height: 30px; padding: 0 12px; font: inherit; font-size: 13px;
  color: #e6ebf2; text-decoration: none; white-space: nowrap; background: var(--site-card);
  border: 1px solid var(--site-line); border-radius: 999px; cursor: pointer; }
.site-all:hover, .site-find:hover { border-color: #ffc94a; }
.site-all b { font: 12px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace; color: #8d99ab; }
.site-find svg { width: 15px; height: 15px; color: #8d99ab; }
.site-find kbd { font: 11px/16px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace; padding: 0 4px; color: #8d99ab;
  border: 1px solid var(--site-line); border-radius: 4px; }
@media (hover: none) { .site-find kbd { display: none; } }
.site-find[hidden] { display: none; }

/* 展开后的搜索框盖在顶栏右侧，窄屏盖满整条 */
.site-bar .site-search { position: absolute; right: 12px; top: 6px; width: min(360px, calc(100% - 24px)); margin: 0; }
.site-bar .site-search input { height: 32px; padding: 0 36px; font-size: 14px; border-radius: 999px; }
.site-bar .site-search > svg { left: 12px; top: 8px; width: 16px; height: 16px; }
.site-search .site-close { position: absolute; right: 4px; top: 4px; width: 24px; height: 24px; padding: 0; font-size: 16px; line-height: 22px;
  color: #8d99ab; background: none; border: none; cursor: pointer; }
.site-search .search-list { max-height: min(70vh, 460px); }
@media (max-width: 600px) {
  .site-bar-in { padding: 0 12px; gap: 8px; }
  .site-logo span { display: none; }
  .site-find span { display: none; }
  .site-find { padding: 0 9px; }
  .site-bar .site-search { left: 8px; right: 8px; width: auto; }
}

/* 搜索框与下拉结果（首页大搜索框与顶栏共用） */
.search { position: relative; z-index: 10; max-width: 32em; }
.search[hidden], .search-list[hidden] { display: none; }
.search > svg { position: absolute; left: 13px; top: 13px; width: 18px; height: 18px; color: #8d99ab; pointer-events: none; }
.search input { width: 100%; height: 44px; padding: 0 40px; font: inherit; color: #e6ebf2; background: var(--site-card);
  border: 1px solid var(--site-line); border-radius: 10px; outline: none; -webkit-appearance: none; appearance: none; transition: border-color .2s; }
.search input::-webkit-search-cancel-button { display: none; }
.search input::placeholder { color: #8d99ab; opacity: .75; }
.search input:focus { border-color: #ffc94a; }
.search kbd { position: absolute; right: 12px; top: 12px; min-width: 20px; padding: 0 5px; font: 12px/20px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  color: #8d99ab; text-align: center; border: 1px solid var(--site-line); border-radius: 5px; pointer-events: none; }
.search input:focus ~ kbd, .search input:not(:placeholder-shown) ~ kbd { display: none; }
@media (hover: none) { .search kbd { display: none; } }

.search-list { position: absolute; top: calc(100% + 6px); left: 0; right: 0; max-height: min(60vh, 460px); overflow-y: auto;
  padding: 6px; background: var(--site-card); border: 1px solid var(--site-line); border-radius: 10px; box-shadow: 0 14px 36px rgba(0,0,0,.55);
  font-size: 14px; line-height: 1.5; }
.search-head, .search-group { display: flex; align-items: center; gap: 6px; padding: 8px 10px 4px; font-size: 12px; color: #8d99ab; }
.search-item + .search-group { border-top: 1px solid var(--site-line-soft); margin-top: 4px; padding-top: 10px; }
.search-group b { font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace; font-weight: normal; }
.search-group i, .search-item i { flex: none; width: 7px; height: 7px; border-radius: 50%; background: var(--c); }
.search-item { display: flex; align-items: center; gap: 10px; padding: 8px 10px; border-radius: 8px; color: #e6ebf2;
  text-decoration: none; font-size: 14px; }
.search-group ~ .search-item { padding-left: 23px; }
.search-item .ti { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.search-item .sub { flex: none; font-size: 12px; color: #8d99ab; }
.search-item mark { background: none; color: #ffc94a; }
.search-item:hover, .search-item.on { background: #151c2a; }
.search-item.on { box-shadow: inset 2px 0 0 var(--c); }
.search-empty { padding: 10px; font-size: 13px; color: #8d99ab; }

/* 学科色（搜索结果的圆点与高亮条） */
.search-list [data-s="physics"]   { --c: #4fc3f7; }
.search-list [data-s="chemistry"] { --c: #c9a7ff; }
.search-list [data-s="biology"]   { --c: #7ee081; }
.search-list [data-s="geography"] { --c: #ffc94a; }