/* ============================================================
   亿电竞主站 · 共享样式 /assets/site.css
   ============================================================ */

/* ---------- 1. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-padding-top: 120px;
  overflow-x: clip;
}
html:focus-within { scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video, picture { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; background: none; border: 0; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  --ink-900: #070B1F;
  --ink-800: #0E1533;
  --ink-700: #141E45;
  --cyan: #35F0E0;
  --violet: #8A5CFF;
  --lime: #B8FF3C;
  --orange: #FF7A45;
  --text: #DCE8FF;
  --muted: #7C8BB0;
  --line: #2A3A63;
  --white: #F7FBFF;

  --rail-w: 88px;
  --shell-w: 1240px;
  --cut: 14px;

  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --ease: cubic-bezier(.22, .8, .28, 1);
}

/* ---------- 3. 基础与中文排版 ---------- */
body {
  min-height: 100vh;
  padding-left: var(--rail-w);
  background-color: var(--ink-900);
  background-image:
    radial-gradient(70% 46% at 84% -8%, rgba(53, 240, 224, .13), transparent 68%),
    radial-gradient(58% 42% at 2% 2%, rgba(138, 92, 255, .15), transparent 72%);
  background-repeat: no-repeat;
  background-attachment: fixed;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 { color: var(--white); font-weight: 800; letter-spacing: -.01em; line-height: 1.15; }
h1 { font-size: clamp(34px, 4.6vw, 56px); line-height: 1.05; letter-spacing: -.02em; }
h2 { font-size: clamp(26px, 3vw, 40px); }
h3 { font-size: clamp(20px, 2vw, 28px); }
strong { color: var(--white); font-weight: 700; }

.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; letter-spacing: .08em; }
.muted { color: var(--muted); }
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

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

.shell {
  width: 100%;
  max-width: calc(var(--shell-w) + 96px);
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 48px);
}

/* ---------- 4. 跳至主要内容 ---------- */
.skip-link {
  position: fixed;
  left: calc(var(--rail-w) + 14px);
  top: -90px;
  z-index: 400;
  padding: 11px 20px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .08em;
  color: #04101F;
  background: var(--cyan);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 9px), calc(100% - 9px) 100%, 0 100%);
  transition: top .22s var(--ease);
}
.skip-link:focus { top: 14px; outline-offset: -4px; }

/* ---------- 5. 品牌轨道 ---------- */
.brand-rail {
  position: fixed;
  inset: 0 auto 0 0;
  width: var(--rail-w);
  z-index: 200;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 20px 0 26px;
  background: linear-gradient(180deg, #0B1230 0%, #070B1F 55%, #0B1230 100%);
  border-right: 1px solid var(--line);
}
.brand-rail__mark {
  display: grid;
  place-items: center;
  padding: 12px 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .18em;
  color: #04101F;
  background: linear-gradient(180deg, var(--cyan), #7FF3FF);
  clip-path: polygon(6px 0, 100% 0, 100% calc(100% - 6px), calc(100% - 6px) 100%, 0 100%, 0 6px);
}
.brand-rail__ticks {
  flex: 1 1 auto;
  width: 1px;
  min-height: 60px;
  background: repeating-linear-gradient(180deg, var(--line) 0 1px, transparent 1px 16px);
}
.brand-rail__label {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .34em;
  color: var(--muted);
}
.brand-rail__coords {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .22em;
  color: var(--cyan);
  opacity: .8;
}

/* ---------- 6. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
}

.brand-bar {
  overflow: hidden;
  max-height: 72px;
  background:
    linear-gradient(90deg, rgba(138, 92, 255, .18), rgba(53, 240, 224, .10) 42%, rgba(7, 11, 31, 0) 88%),
    var(--ink-800);
  border-bottom: 1px solid var(--line);
  transition: max-height .3s var(--ease), opacity .22s var(--ease);
}
.brand-bar__inner {
  display: flex;
  align-items: center;
  gap: 14px 22px;
  min-height: 46px;
  padding-block: 9px;
}
.brand-bar__name {
  flex: 0 0 auto;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--white);
  white-space: nowrap;
}
.brand-bar__tag {
  flex: 1 1 auto;
  min-width: 0;
  font-size: 13px;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.brand-bar__meta {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--muted);
  white-space: nowrap;
}
.brand-bar__status { color: var(--lime); }
.brand-bar__status::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 8px;
  vertical-align: middle;
  background: var(--lime);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}

.site-header.is-condensed .brand-bar { max-height: 0; opacity: 0; }

.nav-bar {
  position: relative;
  background: rgba(7, 11, 31, .88);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .3s var(--ease);
}
.site-header.is-condensed .nav-bar { box-shadow: 0 16px 34px -24px rgba(53, 240, 224, .9); }

.nav-bar__inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: 14px;
  min-height: 68px;
}

/* 品牌标识 */
.brand {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 11px;
}
.brand__mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .06em;
  color: #04101F;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  clip-path: polygon(7px 0, 100% 0, 100% calc(100% - 7px), calc(100% - 7px) 100%, 0 100%, 0 7px);
}
.brand__word {
  display: block;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: .02em;
  line-height: 1.15;
  color: var(--white);
}
.brand__sub {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .26em;
  color: var(--muted);
}

/* 主导航 */
.primary-nav { margin-left: auto; }
.primary-nav > ul { display: flex; align-items: center; gap: 2px; }
.primary-nav li { position: relative; }
.primary-nav a {
  position: relative;
  display: block;
  padding: 11px 13px;
  font-size: 15px;
  color: var(--text);
  transition: color .2s var(--ease), background-color .2s var(--ease);
}
.primary-nav a::before {
  content: "";
  position: absolute;
  left: 11px;
  right: 11px;
  bottom: 5px;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .22s var(--ease);
}
.primary-nav a:hover { color: var(--white); background: rgba(53, 240, 224, .07); }
.primary-nav a:hover::before { transform: scaleX(1); }
.primary-nav a[aria-current="page"] { color: var(--cyan); }
.primary-nav a[aria-current="page"]::before { transform: scaleX(1); }
.primary-nav a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 50%;
  top: -1px;
  width: 6px;
  height: 6px;
  margin-left: -3px;
  background: var(--cyan);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
  box-shadow: 0 0 12px rgba(53, 240, 224, .9);
}

.primary-nav__label { display: inline-block; }
.primary-nav__preview {
  position: absolute;
  right: 0;
  top: calc(100% + 10px);
  width: max-content;
  max-width: 240px;
  padding: 9px 13px;
  font-size: 12px;
  line-height: 1.65;
  color: var(--text);
  background: #0B1230;
  border: 1px solid var(--line);
  border-left: 2px solid var(--cyan);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(-6px);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: opacity .2s var(--ease), transform .2s var(--ease), visibility .2s var(--ease);
}
.primary-nav a:hover .primary-nav__preview,
.primary-nav a:focus-visible .primary-nav__preview {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* 移动端导航按钮 */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  place-items: center;
  border: 1px solid var(--line);
  color: var(--cyan);
  cursor: pointer;
  clip-path: polygon(9px 0, 100% 0, 100% calc(100% - 9px), calc(100% - 9px) 100%, 0 100%, 0 9px);
  transition: border-color .2s var(--ease), background-color .2s var(--ease);
}
.nav-toggle:hover { border-color: var(--cyan); background: rgba(53, 240, 224, .08); }
.nav-toggle:focus-visible { outline-offset: -4px; }
.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  background: var(--cyan);
  transition: background-color .2s var(--ease);
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--cyan);
  transition: transform .22s var(--ease), top .22s var(--ease);
}
.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }
.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); }

/* ---------- 7. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 11px 20px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .04em;
  white-space: nowrap;
  cursor: pointer;
  transition: transform .2s var(--ease), filter .2s var(--ease),
              color .2s var(--ease), border-color .2s var(--ease), background-color .2s var(--ease);
}
.btn:active { transform: translateY(1px); }
.btn--cta {
  color: #04101F;
  background: linear-gradient(115deg, var(--cyan) 0%, #7BF6FF 100%);
  clip-path: polygon(11px 0, 100% 0, 100% calc(100% - 11px), calc(100% - 11px) 100%, 0 100%, 0 11px);
}
.btn--cta:hover { filter: brightness(1.08) saturate(1.15); transform: translateY(-1px); }
.btn--cta:active { transform: translateY(0); }
.btn--cta:focus-visible { outline-color: var(--white); outline-offset: -4px; }
.btn--ghost { color: var(--text); border: 1px solid var(--line); }
.btn--ghost:hover { color: var(--cyan); border-color: var(--cyan); background: rgba(53, 240, 224, .08); }
.btn--block { display: flex; width: 100%; }

/* ---------- 8. 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: 24px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--muted);
}
.crumbs li { display: flex; align-items: center; gap: 8px; }
.crumbs li + li::before { content: "/"; color: var(--line); }
.crumbs a { color: var(--muted); transition: color .2s var(--ease); }
.crumbs a:hover { color: var(--cyan); }
.crumbs [aria-current="page"] { color: var(--text); }

/* ---------- 9. 章节标题 ---------- */
.sec-head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}
.sec-head__idx {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  color: var(--cyan);
}
.sec-head__title {
  font-size: clamp(22px, 2.4vw, 30px);
  font-weight: 800;
  line-height: 1.2;
  color: var(--white);
}
.sec-head__note { margin-left: auto; font-size: 13px; color: var(--muted); }

/* ---------- 10. 正文容器 ---------- */
.prose { max-width: 74ch; }
.prose > * + * { margin-top: 1.15em; }
.prose h2 { font-size: clamp(22px, 2.4vw, 28px); margin-top: 2.2em; }
.prose h3 { font-size: 20px; margin-top: 1.8em; color: var(--white); }
.prose p { font-size: 17px; line-height: 1.85; }
.prose a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 4px;
  text-decoration-thickness: 1px;
  text-decoration-color: rgba(53, 240, 224, .5);
}
.prose a:hover { text-decoration-color: var(--cyan); }
.prose ul, .prose ol { margin-top: 1em; display: grid; gap: .55em; }
.prose li { position: relative; padding-left: 24px; font-size: 16.5px; line-height: 1.8; }
.prose li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: .82em;
  width: 9px;
  height: 1px;
  background: var(--cyan);
}
.prose blockquote {
  margin-top: 1.6em;
  padding: 4px 0 4px 20px;
  border-left: 2px solid var(--violet);
  color: var(--muted);
}
.prose code {
  font-family: var(--font-mono);
  font-size: .92em;
  padding: 2px 6px;
  color: var(--cyan);
  background: rgba(53, 240, 224, .08);
  border: 1px solid rgba(53, 240, 224, .2);
}

/* ---------- 11. 面板与标签 ---------- */
.panel {
  position: relative;
  padding: clamp(20px, 3vw, 32px);
  background: var(--ink-800);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
}
.panel--soft {
  background:
    linear-gradient(150deg, rgba(53, 240, 224, .08), rgba(138, 92, 255, .10) 55%, rgba(14, 21, 51, 0) 100%),
    var(--ink-800);
}
.panel--rail { border-left: 2px solid var(--cyan); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  line-height: 1.6;
  white-space: nowrap;
  color: var(--muted);
  border: 1px solid var(--line);
}
.tag--cyan { color: var(--cyan); border-color: rgba(53, 240, 224, .42); background: rgba(53, 240, 224, .08); }
.tag--violet { color: #B8A7FF; border-color: rgba(138, 92, 255, .45); background: rgba(138, 92, 255, .10); }
.tag--lime { color: var(--lime); border-color: rgba(184, 255, 60, .4); background: rgba(184, 255, 60, .08); }
.tag--orange { color: var(--orange); border-color: rgba(255, 122, 69, .42); background: rgba(255, 122, 69, .10); }

/* ---------- 12. 网格 ---------- */
.grid { display: grid; gap: clamp(16px, 2.4vw, 28px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--aside { grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr); }

/* ---------- 13. 图片容器 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background:
    linear-gradient(140deg, rgba(138, 92, 255, .24), rgba(53, 240, 224, .12) 58%, rgba(7, 11, 31, .9)),
    var(--ink-700);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
}
.media img,
.media video,
.media svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media::after {
  content: "";
  position: absolute;
  left: 16px;
  bottom: 13px;
  width: 52px;
  height: 6px;
  background: repeating-linear-gradient(90deg, var(--cyan) 0 2px, transparent 2px 8px);
  opacity: .78;
  pointer-events: none;
}
.media--wide { aspect-ratio: 21 / 9; }
.media--square { aspect-ratio: 1 / 1; }
.media--tall { aspect-ratio: 3 / 4; }
.media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--muted);
}

/* ---------- 14. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 120px);
  background: linear-gradient(180deg, var(--ink-900) 0%, #0A1130 60%, #0C1436 100%);
  border-top: 1px solid var(--line);
}
.site-footer::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -1px;
  height: 1px;
  background: linear-gradient(90deg, rgba(53, 240, 224, 0), var(--cyan) 22%, var(--violet) 62%, rgba(138, 92, 255, 0));
  opacity: .85;
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(280px, 1fr) minmax(0, 1.5fr);
  gap: clamp(32px, 5vw, 72px);
  padding-block: clamp(44px, 6vw, 72px) clamp(28px, 4vw, 44px);
  align-items: start;
}

.footer-brand__name {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: .02em;
  color: var(--white);
}
.footer-brand__desc {
  margin-top: 12px;
  max-width: 34ch;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}
.footer-brand__status {
  display: inline-block;
  margin-top: 16px;
  padding: 4px 11px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--lime);
  border: 1px solid rgba(184, 255, 60, .32);
  background: rgba(184, 255, 60, .07);
}

.footer-contact {
  display: grid;
  gap: 11px;
  margin-top: 26px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}
.footer-contact__row {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text);
}
.footer-contact__key {
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--cyan);
}
.footer-contact__val { min-width: 0; word-break: break-word; }

.footer-nav {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 0 clamp(18px, 3vw, 30px);
}
.footer-nav__item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 4px;
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
  border-bottom: 1px solid var(--line);
  transition: color .2s var(--ease), border-color .2s var(--ease), padding-left .2s var(--ease);
}
.footer-nav__item:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
  padding-left: 10px;
}
.footer-nav__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--muted);
  transition: color .2s var(--ease);
}
.footer-nav__item:hover .footer-nav__idx { color: var(--cyan); }

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 26px;
  padding-block: 22px 36px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--muted);
}
.footer-base__copy { margin: 0; }
.footer-base__icp {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--muted);
}
.footer-base__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin-left: auto;
}
.footer-base__legal a { color: var(--muted); transition: color .2s var(--ease); }
.footer-base__legal a:hover { color: var(--cyan); }

/* ---------- 15. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 28px);
  bottom: clamp(14px, 3vw, 28px);
  z-index: 210;
  width: 50px;
  height: 50px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: rgba(14, 21, 51, .92);
  color: var(--cyan);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  box-shadow: 0 0 0 1px var(--line), 0 16px 34px -18px rgba(0, 0, 0, .9);
  transition: opacity .26s var(--ease), transform .26s var(--ease), visibility .26s var(--ease), box-shadow .26s var(--ease);
}
.to-top[data-visible] { opacity: 1; visibility: visible; transform: translateY(0); }
.to-top:hover {
  color: var(--white);
  box-shadow: 0 0 0 1px rgba(53, 240, 224, .55), 0 16px 34px -18px rgba(53, 240, 224, .6);
}
.to-top__ring {
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  background: conic-gradient(
    var(--cyan) 0 calc(var(--progress, 0) * 1%),
    rgba(42, 58, 99, .5) calc(var(--progress, 0) * 1%) 100%
  );
  -webkit-mask: radial-gradient(farthest-side, transparent calc(100% - 3px), #000 calc(100% - 3px));
  mask: radial-gradient(farthest-side, transparent calc(100% - 3px), #000 calc(100% - 3px));
  pointer-events: none;
}
.to-top__icon {
  position: relative;
  font-family: var(--font-mono);
  font-size: 17px;
  line-height: 1;
}

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1180px) {
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 38px; }
  .grid--aside { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 1000px) {
  .nav-toggle { display: grid; }

  .primary-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-left: 0;
    display: none;
    padding: 6px 0 18px;
    background: #0B1230;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 26px 44px -26px rgba(0, 0, 0, .98);
  }
  .primary-nav[data-open] { display: block; }
  .primary-nav > ul { flex-direction: column; align-items: stretch; gap: 0; }
  .primary-nav li { position: static; }
  .primary-nav a {
    padding: 14px clamp(18px, 4vw, 48px);
    font-size: 16px;
    border-bottom: 1px solid rgba(42, 58, 99, .6);
  }
  .primary-nav a::before { display: none; }
  .primary-nav a[aria-current="page"] { background: rgba(53, 240, 224, .08); }
  .primary-nav a[aria-current="page"]::after {
    left: 8px;
    top: 50%;
    margin-top: -3px;
    margin-left: 0;
    transform: none;
  }
  .primary-nav__preview {
    position: static;
    display: block;
    width: auto;
    max-width: none;
    margin-top: 5px;
    padding: 0;
    border: 0;
    background: none;
    clip-path: none;
    opacity: 1;
    visibility: visible;
    transform: none;
    pointer-events: auto;
    font-size: 13px;
    color: var(--muted);
  }

  .btn--cta { margin-left: auto; }
}

@media (max-width: 900px) {
  :root { --rail-w: 0px; }
  .brand-rail { display: none; }
  body { padding-left: 0; }
  .skip-link { left: 14px; }
}

@media (max-width: 760px) {
  body { font-size: 16px; }
  .brand-bar__tag { display: none; }
  .brand-bar__inner { min-height: 40px; padding-block: 7px; }
  .brand__sub { display: none; }
  .brand__word { font-size: 16px; }
  .nav-bar__inner { min-height: 60px; gap: 10px; }
  .btn { padding: 10px 14px; font-size: 13px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .footer-nav { grid-template-columns: minmax(0, 1fr); }
  .footer-base { gap: 8px 18px; }
  .footer-base__legal { margin-left: 0; }
  .sec-head { flex-wrap: wrap; }
  .sec-head__note { margin-left: 0; width: 100%; }
}

/* ---------- 17. 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
  html:focus-within { scroll-behavior: auto; }
}