/* ==========================================================================
   宝盈品牌 · 索引台 —— 共享样式表 /assets/site.css
   深海墨蓝基底 / 奶油纸卡面 / 宝盈金编号 / 信号青交互 / 锐利直角 + 精密网格
   ========================================================================== */

/* 1. 基础重置 -------------------------------------------------------------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background-color: var(--ink-900);
  color: var(--text-light);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd, pre { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg, video, canvas { display: block; max-width: 100%; }
a { color: var(--cyan); text-decoration: none; }
button, input, select, textarea { font: inherit; color: inherit; }
table { border-collapse: collapse; width: 100%; }

::selection { background: var(--gold); color: var(--ink-900); }

/* 2. 设计令牌 -------------------------------------------------------------- */
:root {
  /* 色彩 */
  --ink-900: #07141F;
  --ink-700: #0E2233;
  --ink-500: #16344A;
  --line: #2A4A62;
  --paper: #F2E9DB;
  --paper-2: #E2D5C1;
  --gold: #C8A24A;
  --gold-soft: #E3C77E;
  --cyan: #4FD1C5;
  --coral: #E8735A;
  --green: #3FB98A;
  --text-light: #F4EFE6;
  --muted: #9FB0BD;
  --ink-brown: #241C14;

  /* 字体 */
  --font-display: "Barlow Condensed", "Saira Condensed", "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;

  /* 尺度 */
  --shell: 1240px;
  --gutter: clamp(1rem, 4vw, 3rem);
  --header-h: 78px;
  --ease: cubic-bezier(.2, .7, .3, 1);
}

/* 3. 通用工具 -------------------------------------------------------------- */
.container {
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

:focus-visible {
  outline: 2px solid var(--gold-soft);
  outline-offset: 2px;
}

.stack > * + * { margin-top: 1rem; }
.measure { max-width: 38rem; }

/* 4. 排版 ------------------------------------------------------------------ */
.eyebrow {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold);
}

.headline {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2rem, 5vw, 3.5rem);
  line-height: 1.06;
  letter-spacing: .04em;
  color: var(--text-light);
}

.headline--sm {
  font-size: clamp(1.3rem, 2.6vw, 1.75rem);
  letter-spacing: .05em;
}

.lede {
  font-size: clamp(1rem, 1.5vw, 1.125rem);
  line-height: 1.8;
  color: var(--muted);
}

/* 5. 章节外壳与色带 -------------------------------------------------------- */
.section {
  padding-block: clamp(2.5rem, 6vw, 5rem);
}

.section--ink {
  background: var(--ink-700);
}

.section--paper {
  background: var(--paper);
  color: var(--ink-brown);
  --line: #CBB89C;
  --muted: #6B5A45;
  --text-light: var(--ink-brown);
}

.rule {
  display: block;
  height: 8px;
  border: 0;
  background: var(--gold);
}

.rule--cyan { background: var(--cyan); }

.rule--thin {
  height: 1px;
  background: var(--line);
}

/* 6. 按钮 ------------------------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  min-height: 44px;
  padding: .62rem 1.4rem;
  border: 1px solid var(--gold);
  background: var(--gold);
  color: var(--ink-900);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: .1em;
  line-height: 1.2;
  cursor: pointer;
  text-decoration: none;
  transition: background-color .18s var(--ease), color .18s var(--ease),
              border-color .18s var(--ease), box-shadow .18s var(--ease);
}

.btn:hover {
  background: var(--gold-soft);
  border-color: var(--gold-soft);
}

.btn--ghost {
  background: transparent;
  color: var(--gold-soft);
}

.btn--ghost:hover {
  background: rgba(79, 209, 197, .1);
  border-color: var(--cyan);
  color: var(--cyan);
}

.btn--quiet {
  background: var(--ink-500);
  border-color: var(--line);
  color: var(--text-light);
}

.btn--quiet:hover {
  background: var(--ink-700);
  border-color: var(--cyan);
  color: var(--cyan);
}

/* 7. 展览标签 / 说明牌卡面 ------------------------------------------------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .22rem .55rem;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--gold);
  line-height: 1.5;
}

.tag__dot {
  width: 6px;
  height: 6px;
  background: currentColor;
  flex: none;
}

.board {
  position: relative;
  background: var(--paper);
  color: var(--ink-brown);
  border-left: 2px solid var(--gold);
  border-top: 1px solid var(--paper-2);
  padding: clamp(1.1rem, 2.4vw, 1.75rem);
}

.board--ink {
  background: var(--ink-500);
  color: var(--text-light);
  border-left-color: var(--cyan);
  border-top-color: var(--line);
}

.board--ink .lede { color: var(--muted); }

/* 8. 状态 ------------------------------------------------------------------ */
.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: currentColor;
  flex: none;
}

.status-dot--pulse {
  animation: dot-pulse 600ms ease-out 1 both;
}

@keyframes dot-pulse {
  0%   { box-shadow: 0 0 0 0 rgba(79, 209, 197, .55); }
  100% { box-shadow: 0 0 0 10px rgba(79, 209, 197, 0); }
}

.is-error { color: var(--coral); }
.is-ok { color: var(--green); }

/* 9. 栅格 ------------------------------------------------------------------ */
.grid {
  display: grid;
  gap: clamp(1rem, 2.4vw, 1.75rem);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

/* 10. 图片容器（页面阶段插入占位或正式图） --------------------------------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  background: var(--ink-700);
  border: 1px solid var(--line);
}

.media-frame > img,
.media-frame > svg,
.media-frame > picture,
.media-frame > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame--paper {
  background: var(--paper-2);
  border-color: #CBB89C;
}

.media-frame--grid::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(42, 74, 98, .5) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(42, 74, 98, .5) 1px, transparent 1px);
  background-size: 32px 32px;
}

.media-frame--grid > img,
.media-frame--grid > picture { position: relative; z-index: 1; }

.media-frame__tag {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 2;
  padding: .22rem .55rem;
  background: var(--gold);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .12em;
  line-height: 1.5;
}

.media-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  display: flex;
  justify-content: space-between;
  gap: .75rem;
  padding: .5rem .75rem;
  background: rgba(7, 20, 31, .84);
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .06em;
}

/* 11. 面包屑 --------------------------------------------------------------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
  padding-block: 1rem;
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .06em;
  color: var(--muted);
}

.crumbs a { color: var(--muted); }

.crumbs a:hover {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.crumbs__sep { color: var(--line); }

.crumbs [aria-current="page"] { color: var(--gold-soft); }

/* 12. 索引表 --------------------------------------------------------------- */
.index-table {
  width: 100%;
  font-size: .875rem;
  line-height: 1.6;
}

.index-table caption {
  text-align: left;
  padding-bottom: .5rem;
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .14em;
  color: var(--muted);
}

.index-table th,
.index-table td {
  text-align: left;
  padding: .6rem .75rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.index-table th {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .875rem;
  letter-spacing: .1em;
  color: var(--gold);
}

/* 13. 折叠索引 ------------------------------------------------------------- */
.fold {
  border: 1px solid var(--line);
  background: var(--ink-700);
}

.fold + .fold { margin-top: -1px; }

.fold__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .85rem 1rem;
  cursor: pointer;
  list-style: none;
  font-weight: 600;
  transition: color .18s var(--ease), background-color .18s var(--ease);
}

.fold__summary::-webkit-details-marker { display: none; }

.fold__summary::after {
  content: "＋";
  font-family: var(--font-mono);
  font-size: .875rem;
  color: var(--gold);
}

.fold[open] > .fold__summary::after { content: "－"; }

.fold__summary:hover { color: var(--gold-soft); }

.fold[open] {
  border-color: var(--gold);
  background: var(--ink-500);
}

.fold__body {
  padding: 0 1rem 1rem;
  color: var(--muted);
  font-size: .9375rem;
}

/* 14. 序号轨道链接 --------------------------------------------------------- */
.track-link {
  display: flex;
  align-items: baseline;
  gap: .6rem;
  padding: .5rem .75rem;
  border-left: 2px solid transparent;
  color: var(--muted);
  font-size: .8125rem;
  line-height: 1.5;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.track-link:hover { color: var(--text-light); }

.track-link[aria-current="true"] {
  color: var(--gold-soft);
  border-left-color: var(--gold);
}

/* 15. 页头 ---------------------------------------------------------------- */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  z-index: 120;
  padding: .6rem 1.1rem;
  background: var(--gold);
  color: var(--ink-900);
  border: 2px solid var(--ink-900);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .9375rem;
  letter-spacing: .08em;
  transition: top .18s var(--ease);
}

.skip-link:focus { top: .75rem; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--ink-900);
  border-bottom: 1px solid var(--line);
}

.site-header__inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(1rem, 3vw, 2.5rem);
  min-height: var(--header-h);
  padding-block: .8rem;
}

/* 品牌 */
.brand {
  display: flex;
  flex-direction: column;
  gap: .3rem;
  color: inherit;
  flex: none;
}

.brand__mark {
  display: flex;
  align-items: baseline;
  gap: .35rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.35rem;
  line-height: 1;
  letter-spacing: .08em;
  color: var(--text-light);
  transition: color .18s var(--ease);
}

.brand:hover .brand__mark { color: var(--gold-soft); }

.brand__dot { color: var(--gold); }

.brand__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
}

.brand__badge {
  padding: .1rem .38rem;
  background: var(--gold);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .1em;
  line-height: 1.5;
}

.brand__note {
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .06em;
  color: var(--muted);
}

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(.5rem, 1.6vw, 1.25rem);
}

.site-nav__list {
  display: flex;
  align-items: center;
}

.site-nav__item {
  display: flex;
  border-left: 1px solid var(--line);
}

.site-nav__item:first-child { border-left: 0; }

.site-nav__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: .38rem;
  padding: .55rem clamp(.5rem, .9vw, .9rem);
  color: var(--text-light);
  font-size: .875rem;
  font-weight: 500;
  letter-spacing: .02em;
  white-space: nowrap;
  transition: color .18s var(--ease);
}

.site-nav__num {
  font-family: var(--font-mono);
  font-size: .625rem;
  letter-spacing: .08em;
  color: var(--gold);
  transform: translateY(-.1em);
  transition: color .18s var(--ease);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: clamp(.5rem, .9vw, .9rem);
  right: clamp(.5rem, .9vw, .9rem);
  bottom: .3rem;
  height: 1px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .18s var(--ease), background-color .18s var(--ease);
}

.site-nav__link:hover { color: var(--gold-soft); }

.site-nav__link:hover::after {
  transform: scaleX(1);
  background: var(--gold-soft);
}

.site-nav__link[aria-current="page"] { color: var(--gold-soft); }

.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--gold);
}

.site-nav__link[aria-current="page"] .site-nav__num { color: var(--gold-soft); }

.nav-report {
  display: inline-flex;
  align-items: center;
  padding: .48rem 1rem;
  background: var(--gold);
  border: 1px solid var(--gold);
  color: var(--ink-900);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .9375rem;
  letter-spacing: .12em;
  line-height: 1.4;
  white-space: nowrap;
  transition: background-color .18s var(--ease), border-color .18s var(--ease),
              color .18s var(--ease), box-shadow .18s var(--ease);
}

.nav-report:hover {
  background: var(--gold-soft);
  border-color: var(--gold-soft);
  box-shadow: inset 0 0 0 2px rgba(7, 20, 31, .16);
}

/* 移动端按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: .55rem;
  padding: .5rem .75rem;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .12em;
  cursor: pointer;
  transition: border-color .18s var(--ease), color .18s var(--ease);
}

.nav-toggle:hover {
  border-color: var(--gold);
  color: var(--gold-soft);
}

.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 18px;
}

.nav-toggle__bars i {
  display: block;
  height: 1px;
  background: currentColor;
  transition: transform .18s var(--ease), opacity .18s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* 滚动进度 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  pointer-events: none;
  background: transparent;
}

.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 100%;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left center;
}

/* 16. 页脚 ---------------------------------------------------------------- */
.site-footer {
  position: relative;
  background: var(--ink-900);
  border-top: 1px solid var(--line);
  color: var(--text-light);
  padding-bottom: clamp(2rem, 5vw, 3.5rem);
}

.site-footer__band {
  display: block;
  height: 8px;
  background: var(--gold);
}

.site-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.7fr);
  gap: clamp(2rem, 5vw, 4rem);
  padding-block: clamp(2.25rem, 5vw, 3.5rem) clamp(1.75rem, 4vw, 2.75rem);
  border-bottom: 1px solid var(--line);
}

.footer-brand__mark {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.5rem;
  letter-spacing: .08em;
  line-height: 1.1;
  color: var(--text-light);
}

.footer-brand__dot { color: var(--gold); }

.footer-brand__summary {
  margin-top: .55rem;
  font-size: .875rem;
  color: var(--muted);
  max-width: 24ch;
}

.footer-brand__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
  margin-top: 1rem;
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .06em;
  color: var(--muted);
}

.footer-brand__badge {
  padding: .1rem .4rem;
  background: var(--gold);
  color: var(--ink-900);
  letter-spacing: .1em;
  line-height: 1.5;
}

.footer-brand__cta {
  display: inline-flex;
  align-items: center;
  margin-top: 1.25rem;
  padding: .55rem 1.1rem;
  border: 1px solid var(--gold);
  color: var(--gold-soft);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .9375rem;
  letter-spacing: .12em;
  line-height: 1.4;
  transition: background-color .18s var(--ease), color .18s var(--ease),
              border-color .18s var(--ease);
}

.footer-brand__cta:hover {
  background: var(--gold);
  border-color: var(--gold);
  color: var(--ink-900);
}

.footer-nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.25rem, 3vw, 2.5rem);
}

.footer-col__title {
  padding-bottom: .55rem;
  margin-bottom: .75rem;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .9375rem;
  letter-spacing: .14em;
  color: var(--gold);
}

.footer-col__list { display: grid; gap: .25rem; }

.footer-col__list a {
  display: inline-block;
  padding-block: .15rem;
  color: var(--text-light);
  font-size: .875rem;
  border-bottom: 1px solid transparent;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.footer-col__list a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.site-footer__bottom {
  display: grid;
  gap: .4rem;
  padding-block-start: clamp(1.5rem, 3vw, 2rem);
  font-size: .8125rem;
  line-height: 1.7;
  color: var(--muted);
}

.site-footer__contact {
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .8125rem;
  letter-spacing: .02em;
}

.site-footer__note { max-width: 62ch; }

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: .5rem 1.5rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .04em;
}

/* 17. 响应式 -------------------------------------------------------------- */
@media (max-width: 1080px) {
  .site-nav__list { flex-wrap: wrap; }
  .brand__note { display: none; }
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    inset-inline: 0;
    top: 100%;
    display: block;
    max-height: 74vh;
    overflow-y: auto;
    padding: .25rem 0 1.25rem;
    background: var(--ink-700);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 30px 60px -30px rgba(0, 0, 0, .95);
    visibility: hidden;
    opacity: 0;
    transform: translate3d(0, -8px, 0);
    pointer-events: none;
    transition: opacity .18s var(--ease), transform .18s var(--ease),
                visibility 0s linear .18s;
  }

  .site-nav[data-open] {
    visibility: visible;
    opacity: 1;
    transform: none;
    pointer-events: auto;
    transition-delay: 0s;
  }

  .site-nav__list { display: block; }

  .site-nav__item,
  .site-nav__item + .site-nav__item {
    display: block;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .site-nav__item:first-child { border-top: 0; }

  .site-nav__link {
    justify-content: space-between;
    padding: .9rem var(--gutter);
    font-size: 1rem;
    letter-spacing: .04em;
  }

  .site-nav__num {
    order: 2;
    font-size: .75rem;
    transform: none;
  }

  .site-nav__link::after {
    left: var(--gutter);
    right: var(--gutter);
    bottom: 0;
  }

  .site-nav .nav-report {
    display: flex;
    justify-content: center;
    margin: 1.15rem var(--gutter) 0;
    padding: .8rem 1rem;
  }

  .grid--2,
  .grid--3 { grid-template-columns: minmax(0, 1fr); }

  .site-footer__top { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 720px) {
  .site-header__inner { min-height: 68px; }
  .brand__mark { font-size: 1.2rem; }
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .site-footer__legal { flex-direction: column; }
}

@media (max-width: 520px) {
  .brand__mark { font-size: 1.05rem; letter-spacing: .06em; }
  .brand__badge { font-size: .625rem; }
  .nav-toggle { padding: .45rem .6rem; }
  .footer-brand__summary { max-width: none; }
  .media-frame__caption { font-size: .625rem; }
}

/* 18. 减弱动效 ------------------------------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .status-dot--pulse { animation: none; box-shadow: none; }
  .scroll-progress__bar { transition: none; }
}