/* ==========================================================================
   新莆京8883 · 共享站点样式 /assets/site.css
   深墨蓝控制台基调 · 刻度尺语言 · 矿物色数字体系
   ========================================================================== */

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

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

body { margin: 0; }

h1, h2, h3, h4, p, figure, blockquote, dl, dd { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
a { color: inherit; }
button { font: inherit; color: inherit; }
[hidden] { display: none !important; }

:root {
  /* 色板 */
  --ink: #0A1A2A;
  --ink-deep: #061220;
  --ink-2: #12293D;
  --cyan: #2FD3E8;
  --violet: #8E6CF0;
  --amber: #F0A93B;
  --moss: #4E7A5E;
  --clay: #C0694B;
  --rock: #6E7A80;
  --cream: #F4EFE6;
  --silver: #C3D0DA;

  --line: rgba(195, 208, 218, .18);
  --line-strong: rgba(195, 208, 218, .34);
  --text: #E7EEF3;
  --text-dim: #9FB2BE;
  --text-mute: #8B9AA4;

  /* 排版 */
  --font-display: "Songti SC", "Source Han Serif SC", "Noto Serif SC", "STSong", Georgia, serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-num: "DIN Alternate", "Arial Narrow", "Helvetica Neue Condensed", "Roboto Condensed", "PingFang SC", system-ui, sans-serif;

  /* 尺寸 */
  --maxw: 1440px;
  --gutter: 64px;
  --radius-sm: 4px;
  --radius: 8px;
  --radius-lg: 14px;
  --ease: cubic-bezier(.4, 0, .2, 1);
}

body {
  background-color: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  font-weight: 400;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(820px 520px at 8% -6%, rgba(47, 211, 232, .13), transparent 62%),
    radial-gradient(680px 460px at 96% 4%, rgba(142, 108, 240, .12), transparent 64%),
    radial-gradient(900px 620px at 50% 110%, rgba(78, 122, 94, .14), transparent 66%);
}

.site-header,
.site-footer,
main,
#main-content { position: relative; z-index: 1; }

#main-content { scroll-margin-top: 96px; }

html.nav-open { overflow: hidden; }

/* ---------- 基础排版 ---------- */

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: .01em;
  color: #FFFFFF;
}

h1 { font-size: clamp(38px, 5.2vw, 56px); }
h2 { font-size: clamp(26px, 3vw, 34px); }
h3 { font-size: clamp(19px, 2vw, 24px); }
h4 { font-size: 18px; }

p { color: var(--text); }
strong { color: #FFFFFF; font-weight: 700; }

.lede {
  font-size: clamp(17px, 1.6vw, 19px);
  line-height: 1.8;
  color: #C6D3DB;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: currentColor;
  opacity: .85;
}

/* ---------- 数字体系 ---------- */

.num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  letter-spacing: .1em;
  font-weight: 600;
}

.num--cyan { color: var(--cyan); }
.num--amber { color: var(--amber); }
.num--moss { color: #8FB69C; }
.num--violet { color: #B49CF7; }

/* ---------- 焦点与无障碍 ---------- */

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -80px;
  z-index: 200;
  padding: 11px 18px;
  background: var(--cyan);
  color: #06202B;
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
  border-radius: 0 0 var(--radius) var(--radius);
  transition: top .2s var(--ease);
}

.skip-link:focus { top: 0; }

/* ---------- 按钮 ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .04em;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color .22s var(--ease), color .22s var(--ease),
              border-color .22s var(--ease), transform .22s var(--ease);
}

.btn--sm { padding: 8px 14px; font-size: 14px; }
.btn--block { width: 100%; }

.btn--primary {
  background: var(--cyan);
  color: #06202B;
  box-shadow: 0 6px 22px rgba(47, 211, 232, .18);
}
.btn--primary:hover { background: #6FE4F2; color: #04161E; }

.btn--ghost {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--text);
}
.btn--ghost:hover {
  border-color: var(--cyan);
  color: var(--cyan);
  background: rgba(47, 211, 232, .07);
}

.btn--clay {
  background: transparent;
  border-color: rgba(192, 105, 75, .6);
  color: #E8A98F;
}
.btn--clay:hover { background: rgba(192, 105, 75, .14); }

.btn:active { transform: translateY(1px); }
.btn[aria-disabled="true"] { opacity: .5; pointer-events: none; }

/* ==========================================================================
   页头
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(10, 26, 42, .97);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .3s var(--ease);
}

.site-header[data-stuck="true"] {
  box-shadow: 0 14px 34px rgba(3, 10, 18, .6);
}

.site-header__ruler {
  position: relative;
  height: 3px;
  background-color: rgba(195, 208, 218, .06);
  background-image: repeating-linear-gradient(90deg,
    rgba(195, 208, 218, .32) 0 1px, transparent 1px 16px);
}

.site-header__ruler-fill {
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 14px var(--gutter);
}

/* 品牌 */
.brand { min-width: 0; }

.brand__link {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand__mark {
  flex: 0 0 auto;
  padding: 5px 8px;
  font-family: var(--font-num);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .16em;
  line-height: 1;
  color: var(--cyan);
  border: 1px solid rgba(47, 211, 232, .5);
  border-radius: var(--radius-sm);
  background: rgba(47, 211, 232, .07);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.brand__name {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.18;
  letter-spacing: .03em;
  color: #FFFFFF;
}

.brand__tagline {
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--text-mute);
  white-space: nowrap;
}

/* 导航（桌面） */
.site-nav { display: flex; align-items: center; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.site-nav__link {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 8px 13px 10px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: #C0CDD6;
  transition: color .2s var(--ease), background-color .2s var(--ease);
}

.site-nav__idx {
  font-family: var(--font-num);
  font-size: 10px;
  letter-spacing: .16em;
  color: rgba(47, 211, 232, .7);
  transition: color .2s var(--ease);
}

.site-nav__label {
  font-size: 15px;
  letter-spacing: .02em;
  white-space: nowrap;
}

.site-nav__link:hover { color: #FFFFFF; background: rgba(47, 211, 232, .08); }

.site-nav__link[aria-current="page"] {
  color: #FFFFFF;
  background: rgba(47, 211, 232, .1);
}

.site-nav__link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 13px;
  right: 13px;
  bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
}

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

.site-nav__actions { display: none; }

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.nav-close {
  position: absolute;
  top: 20px;
  right: 20px;
  display: none;
  width: 38px;
  height: 38px;
  align-items: center;
  justify-content: center;
  padding: 0;
  font-size: 20px;
  line-height: 1;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.nav-close:hover { color: var(--cyan); border-color: var(--cyan); }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 14px;
  font-size: 14px;
  letter-spacing: .08em;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.nav-toggle:hover { color: var(--cyan); border-color: var(--cyan); }

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: transform .26s var(--ease), top .26s var(--ease);
}
.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

.nav-scrim {
  position: fixed;
  inset: 0;
  z-index: 71;
  padding: 0;
  border: 0;
  background: rgba(5, 14, 24, .64);
  opacity: 0;
  pointer-events: none;
  cursor: pointer;
  transition: opacity .3s var(--ease);
}
.nav-scrim[data-open] { opacity: 1; pointer-events: auto; }

/* ==========================================================================
   页脚
   ========================================================================== */

.site-footer {
  margin-top: 96px;
  background: linear-gradient(180deg, #0A1A2A 0%, var(--ink-deep) 100%);
  border-top: 1px solid var(--line);
}

.site-footer__ruler {
  height: 12px;
  background-color: rgba(195, 208, 218, .05);
  background-image: repeating-linear-gradient(90deg,
    var(--line-strong) 0 1px, transparent 1px 28px);
  border-bottom: 1px solid var(--line);
}

.site-footer__inner {
  display: grid;
  grid-template-columns: 1.6fr .9fr .9fr 1.3fr;
  gap: 40px 44px;
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 56px var(--gutter) 44px;
}

.ftr-brand__name {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: .03em;
  color: #FFFFFF;
}

.ftr-brand__tagline {
  margin-top: 6px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--text-mute);
}

.ftr-brand__note {
  max-width: 36ch;
  margin: 14px 0 20px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-dim);
}

.ftr-col__title {
  position: relative;
  margin-bottom: 16px;
  padding-bottom: 12px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .04em;
  color: #FFFFFF;
}

.ftr-col__title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 32px;
  height: 2px;
  background: var(--cyan);
}

.ftr-col__list li + li { margin-top: 10px; }

.ftr-col__list a {
  font-size: 14.5px;
  color: #A9B9C2;
  text-decoration: none;
  transition: color .2s var(--ease);
}
.ftr-col__list a:hover { color: var(--cyan); }

.ftr-contact__list li {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 12px;
  padding: 9px 0;
  font-size: 14.5px;
  border-bottom: 1px dashed rgba(195, 208, 218, .16);
}
.ftr-contact__list li:last-child { border-bottom: 0; }

.ftr-contact__key {
  padding-top: 5px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--rock);
}

.ftr-contact__val {
  color: #C6D3DB;
  line-height: 1.65;
  word-break: break-word;
}

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 28px;
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 20px var(--gutter) 36px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--rock);
}

.ftr-legal__copy,
.ftr-legal__icp { color: var(--rock); }

.ftr-legal__icp { font-family: var(--font-num); letter-spacing: .1em; }

/* ==========================================================================
   通用布局容器
   ========================================================================== */

.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.container--narrow { max-width: 960px; }
.container--text { max-width: 760px; }

.prose { max-width: 720px; }
.prose p { margin-bottom: 1.05em; }
.prose p:last-child { margin-bottom: 0; }
.prose ul, .prose ol { margin-bottom: 1.05em; padding-left: 1.35em; }
.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose li { margin-bottom: .4em; }
.prose h2, .prose h3 { margin: 1.6em 0 .6em; }
.prose h2:first-child, .prose h3:first-child { margin-top: 0; }

.section { padding: 80px 0; }
.section--tight { padding: 48px 0; }

.section--band {
  background: var(--ink-2);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section--cream {
  background: var(--cream);
  color: #132430;
}
.section--cream h1,
.section--cream h2,
.section--cream h3 { color: var(--ink); }
.section--cream p,
.section--cream li { color: #33454F; }
.section--cream .eyebrow { color: #2B6A74; }
.section--cream .lede { color: #3C4F59; }
.section--cream .rule {
  background: linear-gradient(90deg, rgba(19, 36, 48, .3), rgba(19, 36, 48, .04));
}

/* 网格与 Bento 跨列 */
.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-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: span 12; }

/* ---------- 面板与数据块 ---------- */

.panel {
  position: relative;
  padding: 26px;
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.panel::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan), transparent 62%);
  opacity: .55;
}

.panel--focus {
  border-color: rgba(47, 211, 232, .45);
  background: linear-gradient(158deg, rgba(47, 211, 232, .1), rgba(18, 41, 61, .92) 46%);
}
.panel--violet { border-color: rgba(142, 108, 240, .38); }
.panel--amber { border-color: rgba(240, 169, 59, .38); }
.panel--moss { border-color: rgba(78, 122, 94, .5); }

.stat { display: flex; flex-direction: column; gap: 6px; }

.stat__value {
  font-family: var(--font-num);
  font-size: clamp(28px, 3.4vw, 40px);
  font-weight: 700;
  letter-spacing: .08em;
  line-height: 1;
}

.stat__unit {
  font-family: var(--font-num);
  font-size: 14px;
  letter-spacing: .14em;
  color: var(--rock);
}

.stat__label { font-size: 14px; color: var(--text-dim); }

.strip {
  display: flex;
  flex-wrap: wrap;
  background: rgba(18, 41, 61, .55);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.strip__item {
  flex: 1 1 190px;
  padding: 20px 24px;
  border-right: 1px solid var(--line);
}
.strip__item:last-child { border-right: 0; }

.strip__key {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--rock);
}

.strip__val { display: block; font-size: 17px; color: var(--text); }

/* ---------- 标签 ---------- */

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid currentColor;
  border-radius: 999px;
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .1em;
  line-height: 1.65;
}

.tag--cyan { color: var(--cyan); background: rgba(47, 211, 232, .1); }
.tag--violet { color: #B49CF7; background: rgba(142, 108, 240, .12); }
.tag--amber { color: var(--amber); background: rgba(240, 169, 59, .12); }
.tag--moss { color: #8FB69C; background: rgba(78, 122, 94, .18); }
.tag--clay { color: #E0977C; background: rgba(192, 105, 75, .14); }
.tag--rock { color: var(--silver); background: rgba(195, 208, 218, .08); }

/* ---------- 分隔线 ---------- */

.rule {
  height: 1px;
  margin: 44px 0;
  border: 0;
  background: linear-gradient(90deg, rgba(195, 208, 218, .34), rgba(195, 208, 218, .04));
}

.rule--ticks {
  height: 12px;
  background-color: transparent;
  background-image: repeating-linear-gradient(90deg,
    rgba(195, 208, 218, .42) 0 1px, transparent 1px 22px);
  background-repeat: repeat-x;
  background-size: 22px 6px;
  background-position: 0 center;
}

/* ---------- 面包屑 ---------- */

.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 24px;
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--rock);
}

.crumbs li::after {
  content: "/";
  margin-left: 8px;
  color: rgba(195, 208, 218, .4);
}
.crumbs li:last-child::after { content: ""; margin-left: 0; }

.crumbs a {
  color: var(--silver);
  text-decoration: none;
  transition: color .2s var(--ease);
}
.crumbs a:hover { color: var(--cyan); }
.crumbs [aria-current="page"] { color: var(--cyan); }

/* ---------- 图片容器 ---------- */

.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(47, 211, 232, .08), rgba(142, 108, 240, .07) 45%, rgba(78, 122, 94, .09)),
    var(--ink-2);
}

.media-frame::before {
  content: "";
  display: block;
  padding-top: 56.25%;
}

.media-frame--wide::before { padding-top: 42%; }
.media-frame--tall::before { padding-top: 118%; }
.media-frame--square::before { padding-top: 100%; }

.media-frame::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 10px;
  pointer-events: none;
  background-image: repeating-linear-gradient(90deg,
    rgba(195, 208, 218, .35) 0 1px, transparent 1px 18px);
  background-repeat: repeat-x;
  background-size: 18px 6px;
  background-position: 0 center;
}

.media-frame > img,
.media-frame > picture > img,
.media-frame__inner {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--contain > img,
.media-frame--contain > picture > img,
.media-frame--contain .media-frame__inner { object-fit: contain; }

.media-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 16px 16px 20px;
  font-size: 13px;
  letter-spacing: .05em;
  color: var(--cream);
  background: linear-gradient(0deg, rgba(4, 12, 20, .88), transparent);
}

/* ---------- 标签页 ---------- */

.tabs__list {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  border-bottom: 1px solid var(--line);
  scrollbar-width: none;
}
.tabs__list::-webkit-scrollbar { display: none; }

.tabs__tab {
  flex: 0 0 auto;
  padding: 12px 18px;
  font-family: var(--font-body);
  font-size: 15px;
  letter-spacing: .03em;
  color: #93A5AF;
  background: none;
  border: 0;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.tabs__tab:hover { color: var(--cream); }

.tabs__tab[aria-selected="true"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.tabs__panel { padding-top: 26px; }
.tabs__panel[hidden] { display: none; }

/* ---------- 折叠块 ---------- */

.collapse {
  margin-bottom: 12px;
  background: rgba(18, 41, 61, .62);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.collapse__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 17px 22px;
  font-family: var(--font-body);
  font-size: 16.5px;
  font-weight: 600;
  text-align: left;
  color: var(--text);
  background: none;
  border: 0;
  cursor: pointer;
  transition: color .2s var(--ease), background-color .2s var(--ease);
}
.collapse__trigger:hover { color: var(--cyan); background: rgba(47, 211, 232, .05); }

.collapse__icon {
  position: relative;
  flex: 0 0 auto;
  width: 14px;
  height: 14px;
  color: var(--cyan);
}

.collapse__icon::before,
.collapse__icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: currentColor;
  transform: translate(-50%, -50%);
  transition: transform .26s var(--ease), opacity .26s var(--ease);
}
.collapse__icon::before { width: 14px; height: 2px; }
.collapse__icon::after { width: 2px; height: 14px; }

.collapse__trigger[aria-expanded="true"] .collapse__icon::after {
  transform: translate(-50%, -50%) rotate(90deg);
  opacity: 0;
}

.collapse__panel {
  display: none;
  padding: 0 22px 20px;
}
.collapse__panel[data-open] { display: block; }

/* ---------- 返回顶部 ---------- */

.to-top {
  position: fixed;
  right: 28px;
  bottom: 28px;
  z-index: 55;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  color: var(--cyan);
  background: rgba(10, 26, 42, .93);
  border: 1px solid rgba(47, 211, 232, .5);
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity .25s var(--ease), transform .25s var(--ease),
              background-color .2s var(--ease), color .2s var(--ease);
}

.to-top[data-visible] {
  opacity: 1;
  pointer-events: auto;
  transform: none;
}

.to-top:hover { background: var(--cyan); color: #06202B; }

/* ---------- 滚动显现 ---------- */

.js [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
}

.js [data-reveal].is-in {
  opacity: 1;
  transform: translateY(0);
  transition: opacity .42s ease-out, transform .42s ease-out;
}

/* ==========================================================================
   响应式：平板 1024–1439（抽屉导航 + 两列）
   ========================================================================== */

@media (max-width: 1439px) {
  :root { --gutter: 32px; }

  .site-header__inner { padding-block: 12px; }

  .nav-toggle { display: inline-flex; }
  .header-actions .btn { display: none; }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 72;
    display: flex;
    flex-direction: column;
    width: min(380px, 88vw);
    padding: 92px 28px 40px;
    overflow-y: auto;
    background: var(--ink-2);
    border-left: 1px solid rgba(47, 211, 232, .3);
    transform: translateX(102%);
    visibility: hidden;
    transition: transform .34s var(--ease), visibility 0s linear .34s;
  }

  .site-nav[data-open] {
    transform: translateX(0);
    visibility: visible;
    transition: transform .34s var(--ease), visibility 0s linear 0s;
  }

  .nav-close { display: inline-flex; }

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

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

  .site-nav__link {
    flex-direction: row;
    align-items: baseline;
    gap: 12px;
    padding: 15px 4px;
    border-radius: 0;
  }

  .site-nav__link[aria-current="page"] { background: transparent; }

  .site-nav__link[aria-current="page"]::after {
    left: -12px;
    right: auto;
    top: 50%;
    bottom: auto;
    width: 3px;
    height: 60%;
    transform: translateY(-50%);
  }

  .site-nav__label { font-size: 16px; }

  .site-nav__actions {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-top: 26px;
  }

  .grid { gap: 20px; }
  .span-3, .span-4, .span-5 { grid-column: span 6; }
  .span-7, .span-8, .span-9 { grid-column: span 12; }

  .site-footer__inner {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }
  .ftr-brand { grid-column: 1 / -1; }
}

@media (min-width: 1440px) {
  .nav-scrim { display: none; }
}

/* ==========================================================================
   响应式：手机 < 768
   ========================================================================== */

@media (max-width: 767px) {
  :root { --gutter: 20px; }

  body { font-size: 16px; }

  .brand__link { gap: 10px; }
  .brand__mark { font-size: 12px; padding: 4px 7px; }
  .brand__name { font-size: 18px; }
  .brand__tagline { display: none; }

  .section { padding: 52px 0; }
  .section--tight { padding: 36px 0; }

  .grid { grid-template-columns: 1fr; gap: 18px; }
  .span-3, .span-4, .span-5, .span-6,
  .span-7, .span-8, .span-9, .span-12 { grid-column: 1 / -1; }

  .panel { padding: 20px; }

  .strip__item {
    flex: 1 1 100%;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .strip__item:last-child { border-bottom: 0; }

  .rule { margin: 32px 0; }

  .site-footer { margin-top: 64px; }

  .site-footer__inner {
    grid-template-columns: 1fr;
    gap: 32px;
    padding-top: 40px;
    padding-bottom: 32px;
  }

  .site-footer__legal {
    flex-direction: column;
    align-items: flex-start;
    padding-bottom: 28px;
  }

  .to-top { right: 16px; bottom: 16px; }
}

/* ==========================================================================
   reduced motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

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

  .js [data-reveal].is-in { transition: opacity .2s linear; }

  .site-nav,
  .nav-scrim,
  .to-top,
  .btn,
  .nav-toggle__bars::before,
  .nav-toggle__bars::after { transition-duration: .001ms; }
}