/* ============================================================
   /assets/site.css — 千亿服务 共享外壳
   夜间数字档案馆：深墨蓝墙体 / 纸雾白资料卡 / 鎏金索引线
   ============================================================ */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body { margin: 0; }

h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }
ul, ol { padding: 0; }
ul[class], ol[class] { list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
hr { border: 0; }

:where(a, button, input, textarea, select, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--celadon-500);
  outline-offset: 3px;
}

/* ---------- 2. 变量 ---------- */
:root {
  --ink-950: #081326;
  --ink-900: #0A1830;
  --ink-800: #10213C;
  --ink-700: #1B3152;
  --gold-500: #C99A46;
  --gold-300: #E7C98A;
  --mist-050: #F4F5F2;
  --mist-200: #D8DEE7;
  --celadon-500: #4C8C79;
  --celadon-100: #DDEBE3;
  --slate-400: #8FA0B8;
  --slate-500: #6F7F98;

  --font-display: "Source Han Sans Heavy", "思源黑体 Heavy", "Alibaba PuHuiTi",
    "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui,
    -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", "JetBrains Mono", ui-monospace, SFMono-Regular,
    Menlo, Consolas, monospace;

  --wrap: 1240px;
  --gutter: clamp(1rem, 4vw, 3rem);

  --fs-display: clamp(2.75rem, 7.2vw, 6rem);
  --fs-h1: clamp(2.1rem, 4.6vw, 3.4rem);
  --fs-h2: clamp(1.55rem, 3vw, 2.2rem);
  --fs-h3: clamp(1.1rem, 1.5vw, 1.35rem);

  --hair: 1px solid var(--ink-700);
  --shadow-hard: 6px 6px 0 var(--ink-700);
  --shadow-gold: 6px 6px 0 rgba(201, 154, 70, 0.26);
  --ease: cubic-bezier(0.2, 0.6, 0.2, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  letter-spacing: 0.01em;
  color: var(--ink-950);
  background: var(--mist-050);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.02em;
}

#main-content { scroll-margin-top: 7rem; }

body.nav-open { overflow: hidden; }

/* ---------- 4. 容器与通用排版工具 ---------- */
.container {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding: clamp(3rem, 7vw, 6rem) 0; }
.section--paper { background: var(--mist-050); color: var(--ink-950); }
.section--ink { background: var(--ink-950); color: var(--mist-050); }

.section-head { display: flex; flex-direction: column; gap: 0.9rem; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--gold-500);
}

.eyebrow::before {
  content: "";
  width: 28px;
  height: 1px;
  background: currentColor;
  flex: none;
}

.mono { font-family: var(--font-mono); letter-spacing: 0.02em; }

.rule-gold {
  height: 1px;
  background: var(--gold-500);
  opacity: 0.5;
  margin: 0;
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.5rem;
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  border: 1px solid transparent;
  border-radius: 0;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease),
    border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.btn--gold {
  background: var(--gold-500);
  color: var(--ink-950);
  border-color: var(--gold-500);
  box-shadow: 4px 4px 0 var(--ink-700);
}

.btn--gold:hover { background: var(--gold-300); border-color: var(--gold-300); }

.btn--ghost {
  background: transparent;
  color: var(--mist-050);
  border-color: var(--ink-700);
}

.btn--ghost:hover { border-color: var(--gold-500); color: var(--gold-300); }

.btn--ink {
  background: var(--ink-950);
  color: var(--mist-050);
  border-color: var(--ink-950);
}

.btn--ink:hover { background: var(--ink-800); border-color: var(--ink-800); }

/* ---------- 6. 面包屑 ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--slate-400);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.breadcrumb__list li { display: flex; align-items: center; gap: 0.5rem; }

.breadcrumb__list li::after {
  content: "/";
  color: var(--ink-700);
}

.breadcrumb__list li:last-child::after { content: ""; }

.breadcrumb a:hover,
.breadcrumb a:focus-visible { color: var(--gold-500); }

/* ---------- 7. 正文与网格 ---------- */
.prose {
  max-width: 44em;
  font-size: 1rem;
  line-height: 1.9;
  letter-spacing: 0.01em;
}

.prose > * + * { margin-top: 1.1em; }
.prose p { max-width: 40em; }
.prose ul,
.prose ol { padding-left: 1.25em; list-style: disc; }
.prose li + li { margin-top: 0.35em; }
.prose h2 {
  font-family: var(--font-display);
  font-size: var(--fs-h2);
  line-height: 1.25;
  margin-top: 2em;
}
.prose h3 {
  font-family: var(--font-display);
  font-size: var(--fs-h3);
  margin-top: 1.6em;
}
.prose a { color: inherit; border-bottom: 1px solid var(--gold-500); }
.prose a:hover { color: var(--gold-500); }

.grid {
  display: grid;
  gap: clamp(1rem, 2.5vw, 2rem);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }

/* ---------- 8. 媒体容器（页面阶段放图） ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--ink-700);
  background: var(--ink-800);
  aspect-ratio: 16 / 10;
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }

.media-frame__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(0.72) contrast(1.04);
}

.media-frame__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 0.4rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  background: var(--ink-950);
  color: var(--gold-300);
}

/* ---------- 9. 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.16rem 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  border: 1px solid currentColor;
  color: var(--gold-500);
}

.tag--celadon { color: var(--celadon-500); }
.tag--silver { color: var(--slate-400); }

/* ============================================================
   10. 页头
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--ink-950);
  color: var(--mist-050);
  border-bottom: 1px solid var(--ink-700);
}

/* 跳至主内容 */
.skip-link {
  position: absolute;
  left: 1rem;
  top: -120px;
  z-index: 200;
  padding: 0.7rem 1.1rem;
  background: var(--gold-500);
  color: var(--ink-950);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  border: 1px solid var(--gold-500);
  transition: top 0.18s var(--ease);
}

.skip-link:focus { top: 0.6rem; }

/* 阅读进度 */
.read-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  pointer-events: none;
  background: transparent;
}

.read-progress__bar {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--gold-500), var(--gold-300));
  transition: width 0.1s linear;
}

/* 状态命令带 */
.cmd-bar {
  background: var(--ink-900);
  border-bottom: 1px solid var(--ink-700);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
}

.cmd-bar__inner {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 0.42rem var(--gutter);
  color: var(--mist-200);
  min-width: 0;
}

.cmd-bar__dot {
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--celadon-500);
  box-shadow: 0 0 0 3px rgba(76, 140, 121, 0.18);
}

.cmd-bar__text {
  color: var(--gold-300);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.cmd-bar__meta {
  margin-left: auto;
  color: var(--slate-400);
  white-space: nowrap;
}

/* 主行 */
.masthead__inner {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 3vw, 2.5rem);
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 0.8rem var(--gutter);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: none;
  min-width: 0;
}

.brand__mark {
  display: grid;
  place-items: center;
  flex: none;
  width: 44px;
  height: 44px;
  border: 1.5px solid var(--gold-500);
  color: var(--gold-500);
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, rgba(201, 154, 70, 0.16), transparent 68%);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  min-width: 0;
}

.brand__name {
  display: block;
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: 0.02em;
}

.brand__tagline {
  display: block;
  font-size: 0.68rem;
  line-height: 1.5;
  letter-spacing: 0.08em;
  color: var(--slate-400);
}

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(0.4rem, 1.4vw, 1.25rem);
  margin-left: auto;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(0.15rem, 1.1vw, 1rem);
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-nav__link {
  position: relative;
  display: block;
  padding: 0.45rem 0.4rem;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  color: var(--mist-200);
  white-space: nowrap;
  transition: color 0.2s var(--ease);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0.4rem;
  right: 0.4rem;
  bottom: 0.05rem;
  height: 1px;
  background: var(--gold-500);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.25s var(--ease);
}

.site-nav__link:hover,
.site-nav__link:focus-visible { color: var(--mist-050); }

.site-nav__link:hover::after,
.site-nav__link:focus-visible::after { transform: scaleX(1); }

.site-nav__link[aria-current="page"] { color: var(--gold-300); }

.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--gold-500);
}

.nav-quick {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  flex: none;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--ink-700);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--gold-300);
  white-space: nowrap;
  transition: border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.nav-quick:hover,
.nav-quick:focus-visible {
  border-color: var(--gold-500);
  background: rgba(201, 154, 70, 0.12);
  color: var(--gold-300);
}

/* 移动端索引按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.55rem;
  margin-left: auto;
  padding: 0.5rem 0.7rem;
  border: 1px solid var(--ink-700);
  color: var(--mist-050);
  flex: none;
}

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  background: var(--gold-500);
  transition: background-color 0.18s var(--ease);
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--gold-500);
  transition: transform 0.22s var(--ease);
}

.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }

.nav-toggle__label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
}

.site-header[data-open] .nav-toggle__bars { background: transparent; }
.site-header[data-open] .nav-toggle__bars::before { transform: translateY(6px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { transform: translateY(-6px) rotate(-45deg); }

/* ============================================================
   11. 页脚
   ============================================================ */
.site-footer {
  background: var(--ink-950);
  color: var(--mist-200);
  border-top: 1px solid var(--ink-700);
}

.footer__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) repeat(4, minmax(0, 1fr));
  gap: clamp(1.5rem, 3vw, 2.5rem);
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding: clamp(2.5rem, 6vw, 4.25rem) var(--gutter) clamp(1.75rem, 4vw, 3rem);
}

.footer__brand {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.footer__brandmark {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--mist-050);
  line-height: 1.3;
}

.footer__stamp {
  display: grid;
  place-items: center;
  flex: none;
  width: 34px;
  height: 34px;
  border: 1px solid var(--gold-500);
  color: var(--gold-500);
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 600;
  letter-spacing: 0;
}

.footer__rule {
  display: block;
  width: 56px;
  height: 1px;
  background: var(--gold-500);
  margin: 1.15rem 0;
}

.footer__brandnote {
  max-width: 26ch;
  font-size: 0.82rem;
  line-height: 1.9;
  color: var(--slate-400);
}

.footer-col {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.footer-col__title {
  margin-bottom: 1.1rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--gold-500);
  line-height: 1.6;
}

.footer-col__list {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-link {
  display: inline-block;
  align-self: flex-start;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--mist-200);
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--gold-300);
  border-bottom-color: var(--gold-500);
}

.footer-link--strong {
  margin-top: 0.9rem;
  padding-bottom: 1px;
  color: var(--gold-300);
  border-bottom: 1px solid var(--gold-500);
}

/* 第二栏：稳定版收藏 */
.footer-col--bookmark {
  position: relative;
  padding: 1.1rem 1rem 1.25rem;
  border: 1px solid var(--gold-500);
  background: linear-gradient(160deg, rgba(201, 154, 70, 0.14), rgba(201, 154, 70, 0.02) 62%);
}

.footer-col--bookmark::before {
  content: "";
  position: absolute;
  inset: 4px 4px auto auto;
  width: 8px;
  height: 8px;
  border-top: 1px solid var(--gold-300);
  border-right: 1px solid var(--gold-300);
  opacity: 0.9;
}

.bookmark-badge {
  display: block;
  width: 16px;
  height: 22px;
  margin-bottom: 0.9rem;
  background: var(--gold-500);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 50% 74%, 0 100%);
}

.footer-col__note {
  margin-bottom: 0.9rem;
  font-size: 0.75rem;
  line-height: 1.8;
  color: var(--slate-400);
}

.footer-col--bookmark .footer-col__title { margin-bottom: 0.8rem; }

/* 联系栏 */
.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--mist-200);
  overflow-wrap: anywhere;
}

.footer-contact__line { display: block; }

/* 法务带 */
.footer__legal { border-top: 1px solid var(--ink-700); }

.footer__legal-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem 1.6rem;
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 1.1rem var(--gutter) 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.03em;
  color: var(--slate-500);
}

.footer__copy { color: var(--mist-200); }

.footer__legal-note {
  flex: 1 1 100%;
  font-family: var(--font-body);
  font-size: 0.74rem;
  line-height: 1.8;
  letter-spacing: 0.01em;
  color: var(--slate-500);
}

/* ============================================================
   12. 进入视口显现（需 html.js）
   ============================================================ */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s var(--ease), transform 0.55s var(--ease);
}

html.js [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

/* ============================================================
   13. 响应式
   ============================================================ */
@media (max-width: 1100px) {
  .brand__tagline { display: none; }
  .site-nav__link { font-size: 0.8rem; padding-inline: 0.3rem; }
}

@media (max-width: 940px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    inset: 0;
    z-index: 90;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
    margin: 0;
    padding: 6.5rem var(--gutter) 2.5rem;
    background: var(--ink-950);
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 0.22s var(--ease), transform 0.22s var(--ease),
      visibility 0.22s var(--ease);
  }

  .site-header[data-open] .site-nav {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
  }

  .site-nav__list > li + li { border-top: 1px solid var(--ink-700); }
  .site-nav__list > li:first-child { border-top: 1px solid var(--ink-700); }

  .site-nav__link {
    padding: 1rem 0.25rem;
    font-family: var(--font-display);
    font-size: 1.4rem;
    font-weight: 800;
    letter-spacing: -0.02em;
  }

  .site-nav__link::after { display: none; }
  .site-nav__link[aria-current="page"] { color: var(--gold-300); }
  .site-nav__link[aria-current="page"]::before {
    content: "";
    display: inline-block;
    width: 18px;
    height: 1px;
    margin-right: 0.7rem;
    vertical-align: middle;
    background: var(--gold-500);
  }

  .nav-quick {
    margin-top: 1.75rem;
    justify-content: center;
    padding: 0.9rem 1rem;
    font-size: 0.82rem;
  }

  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer__brand { grid-column: 1 / -1; }
  .footer__brandnote { max-width: 42ch; }
}

@media (max-width: 760px) {
  .cmd-bar__meta { display: none; }

  .masthead__inner { padding-block: 0.7rem; }
  .brand__mark { width: 38px; height: 38px; font-size: 0.76rem; }
  .brand__name { font-size: 1.02rem; }

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

  .prose { max-width: 100%; }
  .prose p { max-width: 100%; }
}

@media (max-width: 560px) {
  .footer__grid { grid-template-columns: minmax(0, 1fr); }
  .footer-col--bookmark { order: -1; }
  .footer__legal-inner { gap: 0.4rem 1rem; }
  .btn { width: 100%; }
}

/* ============================================================
   14. 减少动效
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  html.js [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .read-progress__bar { transition: none; }
}