/* ==========================================================================
   13677-cn.com.cn — 共享外壳样式 /assets/site.css
   夜间档案室 · 蓝图网格 · 索引编号体系
   ========================================================================== */

/* ---------- reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
p, ul, ol, li, figure, figcaption, blockquote, dl, dt, dd {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

img, svg, video, canvas {
  display: block;
  max-width: 100%;
}

a { color: inherit; }

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

table { border-collapse: collapse; }

/* ---------- tokens ---------- */
:root {
  /* 色彩 */
  --ink: #0E1013;
  --glass: #171A20;
  --paper: #F4F0E6;
  --gold: #C9A227;
  --gold-soft: #E8CE8C;
  --gold-ink: #8A6E14;
  --seal: #B4372C;
  --index: #8A8578;
  --pine: #1F3A34;
  --pine-soft: #7FB3A4;
  --umber: #3A2E24;
  --body-mid: #5C5A55;

  /* 排版 */
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  /* 骨架尺寸 */
  --rail: 88px;
  --rail-open: 264px;
  --shell-top: 64px;
  --gutter: clamp(20px, 4vw, 64px);
  --ease: cubic-bezier(.2, .7, .3, 1);
}

/* ---------- 基础排版 ---------- */
html, body { min-height: 100%; }

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.85;
  color: var(--paper);
  background-color: var(--ink);
  background-image:
    linear-gradient(to right, rgba(201, 162, 39, .055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(201, 162, 39, .04) 1px, transparent 1px);
  background-size: 96px 96px, 96px 96px;
  background-position: 0 0, 0 0;
  padding-top: var(--shell-top);
  overflow-x: hidden;
}

p { color: rgba(244, 240, 230, .82); }

h1, h2, h3, h4 {
  font-weight: 900;
  line-height: 1.28;
  letter-spacing: .01em;
  color: var(--paper);
}

.strong { font-weight: 800; }

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

:target { scroll-margin-top: calc(var(--shell-top) + 28px); }

/* ---------- 焦点可见 ---------- */
:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  background: var(--gold);
  border-radius: 2px;
  text-decoration: none;
  transform: translateY(-220%);
  transition: transform 180ms var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
}

/* ==========================================================================
   头部：左侧轨道导航
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--rail);
  z-index: 60;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: rgba(23, 26, 32, .88);
  background-image:
    linear-gradient(to right, rgba(201, 162, 39, .06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(201, 162, 39, .045) 1px, transparent 1px);
  background-size: 22px 22px, 22px 22px;
  border-right: 1px solid rgba(201, 162, 39, .22);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: width 180ms var(--ease), background-color 180ms var(--ease);
}

.site-header:hover,
.site-header:focus-within,
.site-header[data-open="true"] {
  width: var(--rail-open);
  background: rgba(23, 26, 32, .97);
}

/* 品牌 */
.rail-top {
  flex: 0 0 auto;
  border-bottom: 1px solid rgba(201, 162, 39, .16);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 16px;
  text-decoration: none;
}

.brand__mark {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--ink);
  background: var(--gold);
  padding: 5px 6px;
  border-radius: 2px;
  white-space: nowrap;
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  white-space: nowrap;
  opacity: 0;
  transform: translateX(-6px);
  transition: opacity 180ms var(--ease), transform 180ms var(--ease);
}

.brand__name {
  font-size: 15px;
  font-weight: 800;
  color: var(--paper);
  line-height: 1.4;
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .06em;
  color: var(--index);
  line-height: 1.5;
}

.site-header:hover .brand__text,
.site-header:focus-within .brand__text,
.site-header[data-open="true"] .brand__text {
  opacity: 1;
  transform: translateX(0);
}

/* 移动端抽屉按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--paper);
  border: 1px solid rgba(201, 162, 39, .42);
  border-radius: 2px;
  transition: border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.nav-toggle:hover {
  border-color: var(--gold);
  background: rgba(201, 162, 39, .1);
}

.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 18px;
}

.nav-toggle__bars i {
  display: block;
  height: 1px;
  background: var(--gold);
  transition: transform 180ms var(--ease), opacity 140ms linear;
}

.site-header[data-open="true"] .nav-toggle__bars i:nth-child(1) {
  transform: translateY(4px) rotate(45deg);
}

.site-header[data-open="true"] .nav-toggle__bars i:nth-child(2) {
  opacity: 0;
}

.site-header[data-open="true"] .nav-toggle__bars i:nth-child(3) {
  transform: translateY(-4px) rotate(-45deg);
}

/* 导航主体 */
.site-nav {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 14px 0 18px;
  scrollbar-width: thin;
  scrollbar-color: rgba(201, 162, 39, .4) transparent;
}

.site-nav__title {
  padding: 0 20px 10px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--index);
  white-space: nowrap;
}

.site-nav__list {
  display: grid;
  gap: 2px;
}

.site-nav__item { min-width: 0; }

.site-nav__link {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 18px 12px 20px;
  border-left: 2px solid transparent;
  color: rgba(244, 240, 230, .82);
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 160ms var(--ease), border-color 160ms var(--ease), color 160ms var(--ease);
}

.site-nav__link:hover {
  background: rgba(201, 162, 39, .08);
  border-left-color: var(--gold);
  color: var(--paper);
}

.site-nav__link[aria-current="page"] {
  background: rgba(180, 55, 44, .12);
  border-left-color: var(--seal);
  color: #FFFFFF;
}

.site-nav__no {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--gold);
}

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

.site-nav__label {
  font-size: 15px;
  font-weight: 600;
  opacity: 0;
  transform: translateX(-6px);
  transition: opacity 180ms var(--ease), transform 180ms var(--ease);
}

.site-header:hover .site-nav__label,
.site-header:focus-within .site-nav__label,
.site-header[data-open="true"] .site-nav__label {
  opacity: 1;
  transform: translateX(0);
}

.site-nav__actions {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 18px;
  padding: 18px 18px 0;
  border-top: 1px solid rgba(201, 162, 39, .14);
  opacity: 0;
  transition: opacity 180ms var(--ease);
}

.site-header:hover .site-nav__actions,
.site-header:focus-within .site-nav__actions,
.site-header[data-open="true"] .site-nav__actions {
  opacity: 1;
}

.rail-note {
  flex: 0 0 auto;
  padding: 14px 16px;
  border-top: 1px solid rgba(201, 162, 39, .16);
  font-size: 11px;
  line-height: 1.65;
  color: var(--index);
  overflow-wrap: anywhere;
}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 120px);
  border-top: 1px solid rgba(201, 162, 39, .22);
  background:
    linear-gradient(180deg, rgba(23, 26, 32, .78) 0%, rgba(14, 16, 19, 1) 58%),
    radial-gradient(120% 90% at 12% 0%, rgba(31, 58, 52, .5) 0%, rgba(14, 16, 19, 0) 62%);
}

.footer-inner {
  width: 100%;
  max-width: 1360px;
  margin: 0 auto;
  padding: clamp(36px, 5vw, 64px) var(--gutter) 26px;
}

.footer-brand-row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(201, 162, 39, .16);
}

.footer-brand {
  font-size: 18px;
  font-weight: 900;
  letter-spacing: .02em;
  color: var(--paper);
}

.footer-domain {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .12em;
  color: var(--gold);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.05fr 1.05fr 1.3fr 1fr;
  gap: 30px 24px;
  padding: 30px 0 26px;
}

.footer-col { min-width: 0; }

.footer-col__title {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .14em;
  color: var(--gold);
}

.footer-col__no {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  color: rgba(201, 162, 39, .58);
}

.footer-list {
  display: grid;
  gap: 9px;
  margin-top: 14px;
  font-size: 14px;
  line-height: 1.7;
}

.footer-list a {
  color: rgba(244, 240, 230, .74);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.footer-list a:hover {
  color: var(--gold-soft);
  border-bottom-color: rgba(232, 206, 140, .48);
}

.footer-list a[aria-current="page"] {
  color: var(--gold);
  border-bottom-color: rgba(201, 162, 39, .5);
}

.footer-list--plain { color: rgba(244, 240, 230, .6); }

.footer-icp {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .04em;
  color: rgba(244, 240, 230, .55);
}

.footer-contact {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px 24px;
  padding: 22px 0;
  border-top: 1px solid rgba(201, 162, 39, .14);
  font-size: 13.5px;
  color: rgba(244, 240, 230, .68);
}

.footer-contact__item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  min-width: 0;
}

.footer-contact__label {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  color: var(--gold);
}

.footer-tape {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  padding: 18px 0;
  border-top: 1px solid rgba(201, 162, 39, .14);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: rgba(138, 133, 120, .74);
}

.footer-tape span:nth-child(3n) { color: rgba(201, 162, 39, .68); }
.footer-tape span:nth-child(4n) { color: rgba(180, 55, 44, .7); }

.footer-base {
  padding-top: 14px;
  border-top: 1px solid rgba(201, 162, 39, .1);
  font-size: 12.5px;
  color: var(--index);
}

/* ==========================================================================
   通用组件
   ========================================================================== */

/* 顶部滚动进度 */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 120;
  pointer-events: none;
  opacity: 0;
  transition: opacity 220ms var(--ease);
}

.scroll-progress::after {
  content: "";
  display: block;
  height: 100%;
  width: var(--progress, 0%);
  background: linear-gradient(90deg, var(--gold), var(--gold-soft));
  box-shadow: 0 0 12px rgba(201, 162, 39, .5);
}

.scroll-progress[data-visible="true"] { opacity: 1; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .03em;
  text-decoration: none;
  color: var(--paper);
  background: rgba(201, 162, 39, .08);
  border: 1px solid rgba(201, 162, 39, .45);
  border-radius: 2px;
  transition: background-color 160ms var(--ease), border-color 160ms var(--ease), color 160ms var(--ease), transform 160ms var(--ease);
}

.btn:hover {
  background: rgba(201, 162, 39, .18);
  border-color: var(--gold);
  color: var(--gold-soft);
  transform: translateY(-1px);
}

.btn--gold {
  color: var(--ink);
  background: var(--gold);
  border-color: var(--gold);
  font-weight: 800;
}

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

.btn--seal {
  border-color: rgba(180, 55, 44, .62);
  background: rgba(180, 55, 44, .16);
}

.btn--seal:hover {
  border-color: var(--seal);
  background: rgba(180, 55, 44, .28);
  color: #F6D9D4;
}

.btn--quiet {
  background: transparent;
  border-color: rgba(244, 240, 230, .2);
  color: rgba(244, 240, 230, .82);
  font-weight: 500;
}

.btn--quiet:hover {
  border-color: var(--gold);
  background: rgba(201, 162, 39, .1);
  color: var(--gold-soft);
}

/* 面包屑 */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--index);
}

.crumbs a {
  color: var(--index);
  text-decoration: none;
  transition: color 160ms var(--ease);
}

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

.crumbs__sep { color: rgba(138, 133, 120, .6); }

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

/* 页面容器 */
.page-shell {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding-inline: var(--gutter);
}

.page-head {
  padding: clamp(36px, 7vw, 84px) 0 clamp(20px, 3vw, 34px);
  border-bottom: 1px solid rgba(201, 162, 39, .16);
}

.page-title {
  margin-top: 14px;
  font-size: clamp(34px, 6vw, 72px);
  line-height: 1.12;
  letter-spacing: .01em;
}

.page-lede {
  max-width: 62ch;
  margin-top: 18px;
  font-size: 17px;
  color: rgba(244, 240, 230, .76);
}

/* 编号标签 */
.ref-no {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--gold);
  background: rgba(201, 162, 39, .07);
  border: 1px solid rgba(201, 162, 39, .4);
  border-radius: 2px;
  padding: 3px 8px;
  white-space: nowrap;
}

/* 章节标题 */
.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px 18px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(201, 162, 39, .2);
}

.section-head__no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--gold);
}

.section-head__title {
  font-size: clamp(20px, 2.6vw, 28px);
  font-weight: 900;
}

.section-head__note {
  margin-left: auto;
  font-size: 12.5px;
  font-style: italic;
  color: var(--index);
  transform: rotate(-2deg);
}

/* 索引卡 */
.index-card {
  position: relative;
  display: block;
  padding: 22px 22px 20px;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid rgba(58, 46, 36, .3);
  border-radius: 2px;
  text-decoration: none;
  transition: transform 180ms var(--ease), border-color 180ms var(--ease), box-shadow 180ms var(--ease);
}

.index-card::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 22px;
  height: 22px;
  background: linear-gradient(225deg, rgba(201, 162, 39, .28) 0%, rgba(201, 162, 39, .28) 48%, transparent 50%);
}

.index-card:hover,
.index-card:focus-within {
  transform: translateY(-2px);
  border-color: var(--gold);
  box-shadow: 0 14px 34px -18px rgba(0, 0, 0, .85), 0 0 0 1px rgba(201, 162, 39, .45);
}

.index-card__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 14px;
}

.index-card__no {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--gold-ink);
}

.index-card__title {
  margin-top: 12px;
  font-size: 19px;
  font-weight: 900;
  line-height: 1.42;
  color: var(--ink);
}

.index-card__meta {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--index);
}

.index-card__body {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--body-mid);
}

.index-card__note {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed rgba(58, 46, 36, .32);
  font-size: 12.5px;
  font-style: italic;
  color: var(--seal);
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 180ms var(--ease), transform 180ms var(--ease);
}

.index-card:hover .index-card__note,
.index-card:focus-within .index-card__note {
  opacity: 1;
  transform: translateY(0);
}

/* 玻璃层 */
.glass-panel {
  background: rgba(23, 26, 32, .74);
  border: 1px solid rgba(201, 162, 39, .2);
  border-radius: 2px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: 20px 22px;
}

/* 手写批注 */
.annotation {
  display: inline-block;
  font-size: 13px;
  font-style: italic;
  line-height: 1.6;
  color: var(--gold-soft);
  transform: rotate(-2deg);
}

.annotation--seal {
  color: var(--seal);
  transform: rotate(3deg);
}

/* 分隔线 */
.rule {
  height: 1px;
  border: 0;
  background: linear-gradient(90deg, rgba(201, 162, 39, .55), rgba(201, 162, 39, 0));
}

.rule--dashed {
  height: 0;
  border-top: 1px dashed rgba(201, 162, 39, .3);
  background: none;
}

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  color: var(--index);
  border: 1px solid currentColor;
  border-radius: 999px;
  white-space: nowrap;
}

.tag--gold { color: var(--gold); }
.tag--seal { color: var(--seal); }
.tag--pine { color: var(--pine-soft); }

/* 图片容器 */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 4 / 3;
  border: 1px solid rgba(201, 162, 39, .24);
  border-radius: 2px;
  background:
    linear-gradient(135deg, rgba(31, 58, 52, .55) 0%, rgba(23, 26, 32, .9) 55%, rgba(14, 16, 19, 1) 100%);
}

.media-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.92) brightness(.86) contrast(1.05);
  transition: transform 220ms var(--ease), filter 220ms var(--ease);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(105% 80% at 78% 8%, rgba(232, 206, 140, .16) 0%, rgba(14, 16, 19, 0) 58%),
    linear-gradient(180deg, rgba(14, 16, 19, 0) 45%, rgba(14, 16, 19, .72) 100%);
}

.media-frame:hover > img {
  transform: scale(1.02);
  filter: saturate(1) brightness(.95) contrast(1.05);
}

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }

.media-frame__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: rgba(244, 240, 230, .8);
}

/* 对照表 */
.data-table {
  width: 100%;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid rgba(58, 46, 36, .26);
  font-size: 14.5px;
}

.data-table th,
.data-table td {
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid rgba(58, 46, 36, .18);
}

.data-table th {
  font-size: 12.5px;
  font-weight: 800;
  letter-spacing: .08em;
  color: var(--gold-ink);
  background: rgba(201, 162, 39, .1);
}

.data-table tbody tr:last-child td { border-bottom: 0; }

.data-table--dark {
  color: var(--paper);
  background: rgba(23, 26, 32, .7);
  border-color: rgba(201, 162, 39, .22);
}

.data-table--dark th {
  color: var(--gold);
  background: rgba(201, 162, 39, .12);
}

.data-table--dark th,
.data-table--dark td { border-bottom-color: rgba(201, 162, 39, .16); }

/* 纯 CSS 筛选 */
.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.filter-chip {
  position: relative;
  display: inline-flex;
}

.filter-chip input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  opacity: 0;
  cursor: pointer;
}

.filter-chip span {
  display: inline-flex;
  align-items: center;
  padding: 7px 14px;
  font-size: 13.5px;
  color: rgba(244, 240, 230, .78);
  border: 1px solid rgba(244, 240, 230, .2);
  border-radius: 2px;
  transition: background-color 160ms var(--ease), border-color 160ms var(--ease), color 160ms var(--ease);
}

.filter-chip input:hover + span {
  border-color: rgba(201, 162, 39, .6);
  color: var(--gold-soft);
}

.filter-chip input:checked + span {
  color: var(--ink);
  background: var(--gold);
  border-color: var(--gold);
  font-weight: 700;
}

.filter-chip input:focus-visible + span {
  outline: 2px solid var(--gold);
  outline-offset: 2px;
}

/* 旁注条 */
.note-strip {
  padding: 16px 18px;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(244, 240, 230, .8);
  background: rgba(201, 162, 39, .06);
  border-left: 2px solid var(--gold);
}

/* 节奏工具 */
.stack > * + * { margin-top: 24px; }
.stack--tight > * + * { margin-top: 12px; }

.lead {
  font-size: 17px;
  line-height: 1.85;
  color: rgba(244, 240, 230, .8);
}

.muted { color: var(--index); }

.mono {
  font-family: var(--font-mono);
  letter-spacing: .06em;
}

/* 12 列蓝图网格 */
.blueprint-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-6 { grid-column: span 6; }
.span-8 { grid-column: span 8; }
.span-12 { grid-column: span 12; }

/* 展现 */
[data-reveal] {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 300ms var(--ease), transform 300ms var(--ease);
}

[data-reveal][data-revealed="true"] {
  opacity: 1;
  transform: translateY(0);
}

/* 滚动锁 */
body.is-nav-open { overflow: hidden; }

/* ==========================================================================
   响应式
   ========================================================================== */

/* 平板 / 移动：抽屉化 */
@media (max-width: 1023px) {
  .site-header,
  .site-header:hover,
  .site-header:focus-within,
  .site-header[data-open="true"] {
    top: 0;
    right: 0;
    bottom: auto;
    width: auto;
    height: var(--shell-top);
    flex-direction: row;
    align-items: center;
    overflow: visible;
    background: rgba(14, 16, 19, .96);
    border-right: 0;
    border-bottom: 1px solid rgba(201, 162, 39, .24);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }

  .rail-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    width: 100%;
    padding: 0 14px;
    border-bottom: 0;
  }

  .brand { padding: 0; }
  .brand__text { opacity: 1; transform: none; }
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    top: var(--shell-top);
    left: 0;
    right: 0;
    bottom: 0;
    padding: 16px 0 40px;
    background: linear-gradient(180deg, rgba(14, 16, 19, .985) 0%, rgba(23, 26, 32, .985) 100%);
    border-top: 1px solid rgba(201, 162, 39, .14);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity 180ms var(--ease), transform 180ms var(--ease), visibility 0s linear 180ms;
  }

  .site-header[data-open="true"] .site-nav {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    transition: opacity 180ms var(--ease), transform 180ms var(--ease), visibility 0s;
  }

  .site-nav__title { padding: 0 22px 12px; }

  .site-nav__link { padding: 15px 22px; }
  .site-nav__label { opacity: 1; transform: none; font-size: 16px; }
  .site-nav__no { font-size: 12px; }

  .site-nav__actions {
    opacity: 1;
    padding: 20px 22px 0;
    margin-top: 20px;
  }

  .site-nav__actions .btn { width: 100%; }

  .rail-note { display: none; }

  .blueprint-grid { gap: 18px; }
  .span-3, .span-4, .span-6, .span-8 { grid-column: 1 / -1; }

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

/* 桌面 */
@media (min-width: 1024px) {
  body { padding-top: 0; padding-left: var(--rail); }
  .scroll-progress { left: var(--rail); }
}

/* 手机 */
@media (max-width: 639px) {
  body { font-size: 15.5px; }

  .brand__sub { display: none; }
  .brand__name { font-size: 14px; }
  .nav-toggle__label { display: none; }

  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 26px; }
  .footer-contact { grid-template-columns: minmax(0, 1fr); }

  .index-card { padding: 18px 16px 16px; }
  .index-card__title { font-size: 17px; }

  .data-table { font-size: 13.5px; }
  .data-table th,
  .data-table td { padding: 10px 11px; }

  .page-lede { font-size: 16px; }
}

/* 减少动效 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

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

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

  .index-card:hover,
  .index-card:focus-within { transform: none; }

  .btn:hover { transform: none; }

  .media-frame:hover > img { transform: none; }
}