/* ============================================================
   168中体网官网 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 页头 / 页脚 / 基础组件
   ============================================================ */

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

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

body {
  margin: 0;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-sans);
  font-size: clamp(15px, 0.42vw + 14px, 17px);
  line-height: 1.75;
  letter-spacing: 0.01em;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 { line-height: 1.15; margin: 0; font-weight: 800; }
p { margin: 0 0 1em; }
ul, ol { margin: 0; padding: 0; }
img, svg { display: block; max-width: 100%; }
img { height: auto; }
a { color: inherit; }
button { font: inherit; color: inherit; }
strong { font-weight: 700; color: var(--paper); }

::selection { background: var(--mint); color: #04121B; }

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: 3px;
  border-radius: 8px;
}

/* ---------- 变量 ---------- */
:root {
  --ink: #0B1B2B;
  --ink-deep: #081320;
  --panel: #12293D;
  --line: #24455F;
  --mint: #2BE8B0;
  --mint-deep: #0F8F6E;
  --orange: #FF8A3D;
  --orange-soft: #FFC29A;
  --paper: #F4F7FA;
  --mist: #9FB3C4;
  --venue: #4C6B78;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC",
    "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "SF Mono", ui-monospace, "Cascadia Mono", "Roboto Mono",
    Menlo, Consolas, "Courier New", monospace;

  --r-xl: 28px;
  --r-lg: 22px;
  --r-md: 16px;
  --r-pill: 999px;

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --dur: 360ms;

  --header-h: 84px;
  --header-h-sm: 64px;
  --rail-w: 44px;
  --rail-safe: 0px;

  --shell: 1220px;
  --pad: 22px;
}

@media (min-width: 720px) {
  :root { --pad: 32px; }
}

@media (min-width: 1200px) {
  :root { --rail-safe: calc(var(--rail-w) + 10px); }
}

/* ---------- 通用排版 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: calc(var(--pad) + var(--rail-safe)) var(--pad);
}

.shell--narrow { max-width: 860px; }

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

.page-offset { padding-top: calc(var(--header-h) + clamp(28px, 5vw, 64px)); }

.section { padding-block: clamp(44px, 6.5vw, 92px); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px 28px;
  margin-bottom: clamp(24px, 3.6vw, 44px);
}

.section__title {
  font-size: clamp(26px, 3.2vw, 44px);
  letter-spacing: -0.03em;
  line-height: 1.12;
  margin: 0;
  font-weight: 800;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mint);
  background: rgba(43, 232, 176, 0.1);
  border: 1px solid rgba(43, 232, 176, 0.28);
  border-radius: var(--r-pill);
  padding: 5px 12px 6px;
  margin-bottom: 16px;
}

.display {
  font-size: clamp(40px, 6.6vw, 92px);
  font-weight: 800;
  line-height: 1.02;
  letter-spacing: -0.035em;
  margin: 0 0 20px;
  color: var(--paper);
}

.display--xl { font-size: clamp(46px, 8.6vw, 126px); }

.lede {
  font-size: clamp(15px, 1.1vw, 18px);
  line-height: 1.8;
  color: var(--mist);
  max-width: 54ch;
  margin: 0 0 24px;
}

.prose p { max-width: 66ch; color: #D6E1EB; }
.prose h2 { font-size: clamp(22px, 2.4vw, 32px); letter-spacing: -0.02em; margin: 40px 0 14px; }
.prose h3 { font-size: clamp(18px, 1.8vw, 23px); margin: 30px 0 10px; color: var(--paper); }
.prose ul, .prose ol { margin: 0 0 1.2em; padding-left: 1.3em; color: #D6E1EB; }
.prose li { margin-bottom: 0.45em; max-width: 62ch; }

.divider {
  height: 1px;
  border: 0;
  background: linear-gradient(90deg, var(--line), rgba(36, 69, 95, 0));
  margin-block: clamp(30px, 4.6vw, 60px);
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

.figure {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(44px, 7.4vw, 100px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.05em;
  color: var(--mint);
  margin: 0;
  display: block;
}

.figure--orange { color: var(--orange); }

/* ---------- 布局 ---------- */
.split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 64px);
  align-items: start;
}

@media (min-width: 900px) {
  .split { grid-template-columns: 5fr 7fr; }
  .split--flip { grid-template-columns: 7fr 5fr; }
  .split--flip .split__aside { order: 2; }
  .split--flip .split__main { order: 1; }
}

.split__aside, .split__main { min-width: 0; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-decoration: none;
  cursor: pointer;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.btn--sm { padding: 8px 16px; font-size: 13px; }

.btn--mint { background: var(--mint); color: #04121B; border-color: var(--mint); }
.btn--mint:hover { background: #56F3C6; border-color: #56F3C6; transform: translateY(-1px); }

.btn--orange { background: var(--orange); color: #231004; border-color: var(--orange); }
.btn--orange:hover { background: #FFA463; border-color: #FFA463; transform: translateY(-1px); }

.btn--ghost {
  background: rgba(18, 41, 61, 0.5);
  color: var(--paper);
  border-color: var(--line);
}
.btn--ghost:hover {
  color: var(--mint);
  border-color: rgba(43, 232, 176, 0.55);
  background: rgba(43, 232, 176, 0.1);
}

/* ---------- 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  padding: 4px 11px 5px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  color: var(--mist);
  background: rgba(36, 69, 95, 0.3);
  white-space: nowrap;
}

.tag--mint {
  color: var(--mint);
  border-color: rgba(43, 232, 176, 0.42);
  background: rgba(43, 232, 176, 0.1);
}

.tag--orange { color: #231004; background: var(--orange); border-color: var(--orange); }
.tag--soft { color: #3A1B08; background: var(--orange-soft); border-color: var(--orange-soft); }

/* ---------- 卡片 ---------- */
.card {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  padding: clamp(20px, 2.6vw, 32px);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease),
    background var(--dur) var(--ease);
}

.card:hover { border-color: rgba(43, 232, 176, 0.42); }

@media (min-width: 900px) {
  .card--offset-l { margin-left: -24px; }
  .card--offset-r { margin-left: 36px; }
}

/* ---------- 编号步骤 ---------- */
.step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 14px 18px;
  align-items: start;
  padding-block: 16px;
  border-top: 1px solid rgba(36, 69, 95, 0.7);
}

.step:first-child { border-top: 0; }

.step__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(22px, 2.4vw, 32px);
  font-weight: 700;
  line-height: 1;
  color: var(--mint);
  letter-spacing: -0.04em;
  padding-top: 4px;
}

.step__body { min-width: 0; }
.step__body p { margin: 0; color: var(--mist); max-width: 60ch; }
.step__body strong { color: var(--paper); }

/* ---------- 图片容器基础规则 ---------- */
.media {
  position: relative;
  overflow: hidden;
  border-radius: var(--r-xl);
  border: 1px solid var(--line);
  aspect-ratio: 16 / 10;
  width: 100%;
  background:
    radial-gradient(120% 90% at 10% 0%, rgba(43, 232, 176, 0.18), transparent 56%),
    radial-gradient(95% 85% at 102% 104%, rgba(255, 138, 61, 0.16), transparent 62%),
    #0E2233;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(76, 107, 120, 0.2) 1px, transparent 1px),
    linear-gradient(90deg, rgba(76, 107, 120, 0.2) 1px, transparent 1px);
  background-size: 28px 28px;
  -webkit-mask-image: linear-gradient(158deg, #000 12%, transparent 76%);
  mask-image: linear-gradient(158deg, #000 12%, transparent 76%);
}

.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }

.media__img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 1;
}

.media__caption {
  position: absolute;
  left: 16px;
  bottom: 16px;
  z-index: 2;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--mist);
  background: rgba(8, 19, 32, 0.74);
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  padding: 4px 11px;
}

/* ---------- 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--venue);
}

.crumbs__item { display: flex; align-items: center; gap: 8px; }

.crumbs__item + .crumbs__item::before {
  content: "/";
  color: var(--line);
}

.crumbs__link {
  color: var(--mist);
  text-decoration: none;
  transition: color 220ms var(--ease);
}

.crumbs__link:hover { color: var(--mint); }

/* ---------- 页面级竖向索引轨道 ---------- */
.index-rail { display: none; }

@media (min-width: 1020px) {
  .index-rail {
    display: block;
    position: sticky;
    top: 116px;
  }
}

.index-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
  border-left: 1px solid var(--line);
}

.index-rail__item { position: relative; }

.index-rail__link {
  display: block;
  padding: 9px 0 9px 16px;
  margin-left: -1px;
  border-left: 2px solid transparent;
  color: var(--mist);
  text-decoration: none;
  font-size: 13px;
  line-height: 1.5;
  transition: color 220ms var(--ease), border-color 220ms var(--ease);
}

.index-rail__link:hover { color: var(--paper); }

.index-rail__link[aria-current="true"] {
  color: var(--mint);
  border-left-color: var(--mint);
}

.index-rail__mark {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--venue);
  margin-right: 8px;
}

/* ---------- 可展开问答组 ---------- */
.faq {
  display: grid;
  gap: 10px;
  border-radius: var(--r-xl);
}

.faq__item {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  transition: border-color var(--dur) var(--ease);
}

.faq__item:hover { border-color: rgba(43, 232, 176, 0.36); }

.faq__btn {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 18px 22px;
  background: transparent;
  border: 0;
  text-align: left;
  cursor: pointer;
  color: var(--paper);
}

.faq__q { font-size: clamp(15px, 1.3vw, 18px); font-weight: 600; line-height: 1.5; }

.faq__icon {
  position: relative;
  flex: 0 0 auto;
  width: 22px;
  height: 22px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.faq__icon::before,
.faq__icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  translate: -50% -50%;
  background: var(--mint);
  border-radius: 2px;
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.faq__icon::before { width: 10px; height: 2px; }
.faq__icon::after { width: 2px; height: 10px; }

.faq__btn[aria-expanded="true"] .faq__icon { border-color: rgba(43, 232, 176, 0.6); }
.faq__btn[aria-expanded="true"] .faq__icon::after { opacity: 0; transform: scaleY(0); }

.faq__panel { padding: 0 22px 20px; }
.faq__panel p { margin: 0 0 0.7em; color: var(--mist); max-width: 62ch; }
.faq__panel p:last-child { margin-bottom: 0; }

/* ---------- 显现协议 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 620ms var(--ease), transform 620ms var(--ease);
}

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

/* ============================================================
   页头
   ============================================================ */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 900;
  color: var(--paper);
  background: transparent;
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(180deg, rgba(7, 17, 28, 0.94) 0%, rgba(7, 17, 28, 0.55) 58%, rgba(7, 17, 28, 0) 100%);
  transition: opacity var(--dur) var(--ease);
  pointer-events: none;
}

.site-header[data-scrolled] {
  background: rgba(11, 27, 43, 0.97);
  box-shadow: inset 0 -1px 0 var(--line), 0 22px 46px -32px #000;
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
}

.site-header[data-scrolled]::before { opacity: 0; }

.header__inner {
  position: relative;
  max-width: var(--shell);
  margin-inline: auto;
  min-height: var(--header-h);
  padding: 14px var(--pad);
  padding-left: calc(var(--pad) + var(--rail-safe));
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 30px);
  transition: min-height var(--dur) var(--ease), padding var(--dur) var(--ease);
}

.site-header[data-scrolled] .header__inner {
  min-height: var(--header-h-sm);
  padding-top: 8px;
  padding-bottom: 8px;
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  flex: 0 0 auto;
  text-decoration: none;
  color: var(--paper);
}

.brand__mark {
  font-family: var(--font-mono);
  font-size: 21px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.05em;
  color: var(--mint);
  padding: 5px 8px 6px;
  border: 1px solid rgba(43, 232, 176, 0.45);
  border-radius: 11px;
  background: rgba(43, 232, 176, 0.09);
  transition: background var(--dur) var(--ease);
}

.brand:hover .brand__mark { background: rgba(43, 232, 176, 0.2); }

.brand__name {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.03em;
  line-height: 1;
}

.brand__ver {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1;
  color: #2A1204;
  background: var(--orange);
  border-radius: var(--r-pill);
  padding: 4px 9px 5px;
}

.brand--footer { margin-bottom: 18px; }

/* 导航 */
.nav { margin-left: auto; }

.nav__list {
  display: flex;
  align-items: center;
  gap: 3px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav__item { list-style: none; }

.nav__link {
  position: relative;
  display: inline-block;
  padding: 9px 14px 10px;
  border-radius: var(--r-pill);
  color: var(--mist);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.02em;
  text-decoration: none;
  white-space: nowrap;
  transition: color 240ms var(--ease), background 240ms var(--ease);
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 3px;
  translate: -50% 0;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--mint);
  transition: width 300ms var(--ease);
}

.nav__link:hover,
.nav__link:focus-visible {
  color: var(--paper);
  background: rgba(43, 232, 176, 0.09);
}

.nav__link[aria-current="page"] { color: var(--mint); }
.nav__link[aria-current="page"]::after { width: 18px; }

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

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 14px 9px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(43, 232, 176, 0.4);
  background: rgba(43, 232, 176, 0.1);
  color: var(--mint);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 240ms var(--ease), border-color 240ms var(--ease);
}

.nav-toggle:hover { background: rgba(43, 232, 176, 0.2); }

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 10px;
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 300ms var(--ease), opacity 200ms var(--ease);
}

.nav-toggle__bars::before { top: 0; }
.nav-toggle__bars::after { bottom: 0; }

.site-header[data-open] .nav-toggle__bars::before { transform: translateY(4px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { transform: translateY(-4px) rotate(-45deg); }

.nav-toggle__text { line-height: 1; }

/* 抽屉态 */
@media (max-width: 1020px) {
  .nav-toggle { display: inline-flex; }

  .site-header[data-open] {
    background: rgba(9, 22, 36, 0.99);
    box-shadow: inset 0 -1px 0 var(--line);
  }

  .site-header[data-open]::before { opacity: 0; }

  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin: 0;
    padding: 10px var(--pad) 26px;
    background: rgba(9, 22, 36, 0.99);
    border-top: 1px solid rgba(36, 69, 95, 0.8);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 40px 54px -30px #000;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    pointer-events: none;
    max-height: calc(100dvh - var(--header-h-sm));
    overflow-y: auto;
    transition: opacity 280ms var(--ease), transform 280ms var(--ease),
      visibility 280ms var(--ease);
  }

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

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

  .nav__link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px 12px 15px 24px;
    border-radius: 14px;
    border-bottom: 1px solid rgba(36, 69, 95, 0.45);
    font-size: 16px;
    font-weight: 600;
  }

  .nav__item:last-child .nav__link { border-bottom: 0; }

  .nav__link::before {
    content: "";
    position: absolute;
    left: 8px;
    top: 50%;
    translate: 0 -50%;
    width: 2px;
    height: 14px;
    border-radius: 2px;
    background: var(--line);
    transition: background 240ms var(--ease), height 240ms var(--ease);
  }

  .nav__link::after {
    position: static;
    translate: none;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--mint);
    opacity: 0;
    transition: opacity 240ms var(--ease);
  }

  .nav__link[aria-current="page"]::before { background: var(--mint); height: 24px; }
  .nav__link[aria-current="page"]::after { opacity: 1; }
}

@media (max-width: 560px) {
  .header__cta { display: none; }
  .brand__ver { display: none; }
  .brand__name { font-size: 17px; }
}

/* 全站竖向轨道 */
.scroll-rail {
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  width: var(--rail-w);
  display: none;
  z-index: 800;
  pointer-events: none;
  border-right: 1px solid rgba(36, 69, 95, 0.55);
  background: linear-gradient(180deg, rgba(15, 143, 110, 0.1), rgba(43, 232, 176, 0) 46%);
}

@media (min-width: 1200px) {
  .scroll-rail { display: block; }
}

.scroll-rail__ticks {
  position: absolute;
  left: 11px;
  top: 22%;
  bottom: 18%;
  width: 9px;
  background-image: repeating-linear-gradient(
    180deg,
    rgba(36, 69, 95, 0.95) 0 1px,
    transparent 1px 38px
  );
}

.scroll-rail__track {
  position: absolute;
  left: 21px;
  top: 14%;
  bottom: 14%;
  width: 2px;
  border-radius: 2px;
  background: rgba(36, 69, 95, 0.85);
  overflow: hidden;
}

.scroll-rail__progress {
  display: block;
  width: 100%;
  height: 0%;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--mint), var(--mint-deep));
  transition: height 120ms linear;
}

.scroll-rail__mark {
  position: absolute;
  left: 50%;
  bottom: 22px;
  translate: -50% 0;
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--venue);
}

/* skip link */
.skip-link {
  position: absolute;
  left: 14px;
  top: -72px;
  z-index: 1200;
  padding: 10px 20px;
  border-radius: var(--r-pill);
  background: var(--mint);
  color: #04121B;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transition: top 240ms var(--ease);
}

.skip-link:focus {
  top: 14px;
  outline: 2px solid #04121B;
  outline-offset: 2px;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 9vw, 132px);
  background: linear-gradient(180deg, #0A1725 0%, var(--ink-deep) 100%);
  border-top: 1px solid var(--line);
  color: var(--mist);
  font-size: 14px;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, var(--mint) 0%, rgba(43, 232, 176, 0) 42%);
}

.footer__inner {
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(38px, 5.5vw, 68px) var(--pad) 26px;
  padding-left: calc(var(--pad) + var(--rail-safe));
}

.footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 46px);
}

@media (min-width: 720px) {
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1020px) {
  .footer__grid { grid-template-columns: 1.4fr 1fr 1fr 1.2fr; }
}

.footer__col { min-width: 0; }

.footer__title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mint);
  margin: 0 0 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(36, 69, 95, 0.6);
}

.footer__note {
  margin: 0 0 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--venue);
}

.footer__icp {
  display: inline-block;
  margin: 0 0 12px;
  padding: 4px 12px 5px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--mist);
}

.footer__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 11px;
}

.footer__list a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #C4D2DE;
  text-decoration: none;
  transition: color 220ms var(--ease);
}

.footer__list a::before {
  content: "";
  display: block;
  width: 12px;
  height: 1px;
  background: var(--line);
  transition: width 240ms var(--ease), background 240ms var(--ease);
}

.footer__list a:hover { color: var(--mint); }
.footer__list a:hover::before { width: 20px; background: var(--mint); }

.footer__contact {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.footer__contact li { display: grid; gap: 3px; }

.footer__label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--venue);
}

.footer__value {
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--paper);
  word-break: break-word;
}

.footer__value--text {
  font-family: var(--font-sans);
  font-size: 13.5px;
  color: var(--mist);
  line-height: 1.7;
}

.footer__base {
  margin-top: clamp(30px, 4.4vw, 54px);
  padding-top: 20px;
  border-top: 1px solid rgba(36, 69, 95, 0.7);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 28px;
  font-size: 12.5px;
  color: var(--venue);
}

.footer__stamp {
  margin: 0;
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

.footer__meta { margin: 0; }

.footer__ver {
  color: var(--orange);
  font-weight: 700;
  letter-spacing: 0.06em;
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

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

  .scroll-rail__progress { transition: none; }
  .btn:hover { transform: none; }
}