/* ============================================================
   6686主页 · 共享样式表 /assets/site.css
   框架式导航 · 目录型内容地图 · 冷底暖点 · 粗野主义细节
   ============================================================ */

/* ---------- 1. 设计令牌 ---------- */
:root {
  --ink-900: #08182C;
  --ink-800: #0E2440;
  --line-700: #1C3D63;
  --cyan-500: #2FE0D0;
  --cyan-700: #12A79B;
  --ember-500: #FF8A3D;
  --ember-300: #FFB877;
  --violet: #7B6CF6;
  --mist-300: #C6D0DB;
  --paper-100: #F5F2EB;
  --amber-400: #FFD166;
  --shadow-ink: #04101F;

  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, "IBM Plex Mono", "JetBrains Mono", SFMono-Regular, Menlo, Consolas, monospace;

  --rail-w: 232px;
  --bar-h: 56px;
  --edge: 32px;
  --gap: 24px;
  --frame: 2px;
  --radius: 2px;
  --shadow-hard: 8px 8px 0 var(--shadow-ink);
  --shadow-hard-lg: 12px 12px 0 var(--shadow-ink);
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 2. Reset 与基础 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  min-block-size: 100%;
  background-color: var(--ink-900);
  background-image:
    radial-gradient(120% 70% at 84% -12%, rgba(47, 224, 208, .075), transparent 60%),
    radial-gradient(95% 62% at -12% 104%, rgba(123, 108, 246, .062), transparent 62%);
  background-repeat: no-repeat;
  color: var(--paper-100);
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.75;
  padding-block-start: var(--bar-h);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 扫描线纹理，透明度低于 6% */
body::before {
  content: "";
  position: fixed;
  inset: -4px 0 0 0;
  z-index: 1;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    to bottom,
    rgba(245, 242, 235, .045) 0,
    rgba(245, 242, 235, .045) 1px,
    transparent 1px,
    transparent 4px
  );
  animation: scan-drift 12s linear infinite;
}

@keyframes scan-drift {
  from { transform: translateY(0); }
  to { transform: translateY(4px); }
}

h1, h2, h3, h4, h5, h6, p, figure, blockquote {
  margin: 0;
}

ul, ol {
  margin: 0;
  padding: 0;
}

ul[class],
ol[class] {
  list-style: none;
}

img, svg, video {
  max-inline-size: 100%;
}

a {
  color: var(--cyan-500);
  text-decoration: none;
}

a:hover {
  color: var(--paper-100);
}

button {
  font-family: inherit;
}

:focus-visible {
  outline: 3px solid var(--cyan-500);
  outline-offset: 3px;
  border-radius: 1px;
}

::selection {
  background: var(--cyan-500);
  color: var(--ink-900);
}

/* ---------- 3. 排版工具 ---------- */
.display {
  font-size: clamp(44px, 8vw, 120px);
  font-weight: 300;
  letter-spacing: -.04em;
  line-height: .98;
  color: var(--paper-100);
}

.page-title {
  font-size: clamp(30px, 4.4vw, 56px);
  font-weight: 300;
  letter-spacing: -.03em;
  line-height: 1.06;
  color: var(--paper-100);
}

.section-title {
  font-size: clamp(22px, 2.4vw, 32px);
  font-weight: 400;
  letter-spacing: -.025em;
  line-height: 1.2;
  color: var(--paper-100);
}

.lede {
  max-inline-size: 42ch;
  font-size: clamp(16px, 1.25vw, 19px);
  line-height: 1.7;
  color: var(--mist-300);
}

.prose {
  max-inline-size: 40em;
  color: var(--mist-300);
}

.prose p + p {
  margin-block-start: 1em;
}

.prose strong {
  color: var(--paper-100);
  font-weight: 600;
}

.eyebrow,
.index-num {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .14em;
  line-height: 1.4;
  color: var(--cyan-500);
  text-transform: uppercase;
}

.u-mono {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
}

.sr-only {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---------- 4. 布局工具 ---------- */
.container {
  inline-size: 100%;
  max-inline-size: 1240px;
  margin-inline: auto;
  padding-inline: var(--edge);
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gap);
}

.grid--8 { grid-template-columns: repeat(8, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.stack {
  display: flex;
  flex-direction: column;
  gap: var(--gap);
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px 24px;
  padding-block-end: 14px;
  border-block-end: var(--frame) solid var(--line-700);
}

.divider {
  block-size: 0;
  margin-block: 48px;
  border: 0;
  border-block-start: 1px solid var(--line-700);
}

/* ---------- 5. 按钮 ---------- */
.btn {
  --btn-bg: var(--ink-800);
  --btn-fg: var(--paper-100);
  --btn-line: var(--line-700);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-block-size: 44px;
  padding: 10px 18px;
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -.01em;
  line-height: 1.3;
  text-align: center;
  color: var(--btn-fg);
  background-color: var(--btn-bg);
  border: var(--frame) solid var(--btn-line);
  border-radius: var(--radius);
  box-shadow: 4px 4px 0 var(--shadow-ink);
  cursor: pointer;
  transition: transform .18s var(--ease), box-shadow .18s var(--ease),
              background-color .18s var(--ease), color .18s var(--ease),
              border-color .18s var(--ease);
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 var(--shadow-ink);
  color: var(--btn-fg);
}

.btn:active {
  transform: translate(0, 0);
  box-shadow: 2px 2px 0 var(--shadow-ink);
}

.btn--primary {
  --btn-bg: var(--ember-500);
  --btn-fg: #2A1204;
  --btn-line: #B85A17;
}

.btn--primary:hover { --btn-bg: var(--ember-300); }

.btn--accent {
  --btn-bg: var(--cyan-500);
  --btn-fg: #04231F;
  --btn-line: #12867D;
}

.btn--accent:hover { --btn-bg: #6BF0E4; }

.btn--ghost {
  --btn-bg: transparent;
  --btn-line: var(--line-700);
}

.btn--ghost:hover {
  --btn-line: var(--cyan-500);
  --btn-fg: var(--cyan-500);
}

.btn--block {
  display: flex;
  inline-size: 100%;
}

/* ---------- 6. 标签 / 面板 / 表格 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  min-block-size: 24px;
  padding: 2px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .1em;
  line-height: 1.5;
  color: var(--ink-900);
  background-color: var(--ember-300);
  border-radius: 2px;
}

.tag--cyan { background-color: var(--cyan-500); }
.tag--violet { background-color: var(--violet); color: var(--paper-100); }

.panel {
  background-color: var(--ink-800);
  border: var(--frame) solid var(--line-700);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-hard);
}

.panel--flat { box-shadow: none; }

.table-wrap {
  inline-size: 100%;
  overflow-x: auto;
  overscroll-behavior-x: contain;
}

.table {
  inline-size: 100%;
  min-inline-size: 520px;
  border-collapse: collapse;
  font-size: 15px;
  color: var(--mist-300);
}

.table th,
.table td {
  padding: 12px 14px;
  text-align: start;
  border-block-end: 1px solid var(--line-700);
  vertical-align: top;
}

.table th {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .14em;
  color: var(--cyan-500);
  border-block-end: var(--frame) solid var(--line-700);
  white-space: nowrap;
}

.table tbody tr { transition: background-color .16s var(--ease); }
.table tbody tr:hover { background-color: rgba(47, 224, 208, .07); }
.table td:first-child { color: var(--paper-100); font-weight: 500; }

/* ---------- 7. 面包屑 ---------- */
.breadcrumb {
  padding-block: 14px;
  border-block-end: 1px solid var(--line-700);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--mist-300);
}

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

.breadcrumb__item::after {
  content: "/";
  color: var(--line-700);
}

.breadcrumb__item:last-child::after { content: none; }

.breadcrumb__link {
  color: var(--mist-300);
  text-decoration: none;
  transition: color .16s var(--ease);
}

.breadcrumb__link:hover { color: var(--cyan-500); }

.breadcrumb__link[aria-current="page"] {
  color: var(--paper-100);
  border-block-end: 2px solid var(--cyan-500);
}

/* ---------- 8. 图片容器 ---------- */
.media {
  position: relative;
  display: block;
  inline-size: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--ink-800);
  border: var(--frame) solid var(--line-700);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard);
}

.media > img,
.media > svg,
.media > video {
  display: block;
  inline-size: 100%;
  block-size: 100%;
  object-fit: cover;
}

.media--wide { aspect-ratio: 21 / 9; }
.media--square { aspect-ratio: 1 / 1; }
.media--tall { aspect-ratio: 3 / 4; }

.media__caption {
  position: absolute;
  inset-block-end: 0;
  inset-inline: 0;
  margin: 0;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--paper-100);
  background: rgba(8, 24, 44, .86);
  border-block-start: 1px solid var(--line-700);
}

.media-stack {
  display: grid;
  gap: 20px;
}

@media (min-width: 900px) {
  .media-stack {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    align-items: start;
  }
  .media-stack > :nth-child(3n + 1) { grid-column: 1 / span 7; }
  .media-stack > :nth-child(3n + 2) {
    grid-column: 6 / span 7;
    margin-block-start: 36px;
  }
  .media-stack > :nth-child(3n + 3) {
    grid-column: 3 / span 8;
    margin-block-start: -12px;
  }
}

/* ---------- 9. 头部框架 ---------- */
.site-header {
  position: relative;
  z-index: 70;
}

.skip-link {
  position: fixed;
  inset-block-start: 8px;
  inset-inline-start: 8px;
  z-index: 130;
  display: inline-flex;
  align-items: center;
  min-block-size: 44px;
  padding: 10px 18px;
  font-size: 15px;
  font-weight: 600;
  color: var(--ink-900);
  background-color: var(--cyan-500);
  border: var(--frame) solid var(--ink-900);
  border-radius: var(--radius);
  box-shadow: 4px 4px 0 var(--shadow-ink);
  transform: translateY(-180%);
  transition: transform .18s var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
  color: var(--ink-900);
}

/* 顶部快捷条 */
.topbar {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  z-index: 60;
  block-size: var(--bar-h);
  display: flex;
  align-items: center;
  gap: 16px;
  padding-inline: var(--edge);
  background-color: var(--ink-800);
  border-block-end: var(--frame) solid var(--line-700);
}

.topbar__brand {
  display: flex;
  align-items: baseline;
  gap: 6px;
  flex: 0 0 auto;
  text-decoration: none;
  color: var(--paper-100);
}

.topbar__brand:hover { color: var(--paper-100); }

.topbar__mark {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: -.02em;
  color: var(--cyan-500);
}

.topbar__name {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -.01em;
}

.quickbar {
  flex: 1 1 auto;
  min-inline-size: 0;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scrollbar-width: thin;
  scrollbar-color: var(--line-700) transparent;
}

.quickbar__list {
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
}

.quickbar__item { flex: 0 0 auto; }

.quickbar__link {
  position: relative;
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  min-block-size: 40px;
  padding: 5px 14px 5px 16px;
  overflow: hidden;
  text-decoration: none;
  color: var(--paper-100);
  background-color: rgba(8, 24, 44, .62);
  border: 1px solid var(--line-700);
  border-radius: var(--radius);
  transition: color .2s var(--ease), border-color .2s var(--ease),
              background-color .2s var(--ease);
}

.quickbar__link::before {
  content: "";
  position: absolute;
  inset-block: 0;
  inset-inline-start: 0;
  inline-size: 3px;
  background-color: var(--cyan-500);
  transform: scaleY(0);
  transform-origin: center top;
  transition: transform .24s var(--ease);
}

.quickbar__link:hover {
  color: var(--paper-100);
  border-color: var(--cyan-700);
  background-color: rgba(47, 224, 208, .08);
}

.quickbar__link:hover::before { transform: scaleY(1); }

.quickbar__label {
  position: relative;
  z-index: 1;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: -.01em;
  line-height: 1.25;
}

.quickbar__hint {
  position: relative;
  z-index: 1;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  line-height: 1.4;
  color: var(--mist-300);
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
  margin-inline-start: auto;
  min-block-size: 40px;
  padding: 8px 12px;
  font-size: 14px;
  font-weight: 600;
  color: var(--paper-100);
  background-color: rgba(8, 24, 44, .62);
  border: 1px solid var(--line-700);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color .2s var(--ease), color .2s var(--ease);
}

.nav-toggle:hover {
  border-color: var(--cyan-500);
  color: var(--cyan-500);
}

.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  justify-content: space-between;
  inline-size: 18px;
  block-size: 12px;
}

.nav-toggle__bars span {
  display: block;
  block-size: 2px;
  background-color: currentColor;
  transition: transform .2s var(--ease), opacity .2s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* 左侧频道索引栏 */
.rail {
  position: fixed;
  inset-block-start: var(--bar-h);
  inset-block-end: 0;
  inset-inline-start: 0;
  z-index: 55;
  inline-size: var(--rail-w);
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 18px 14px 16px;
  overflow-y: auto;
  overscroll-behavior: contain;
  background-color: var(--ink-800);
  border-inline-end: var(--frame) solid var(--line-700);
  scrollbar-width: thin;
  scrollbar-color: var(--line-700) transparent;
}

.rail__title {
  margin: 0;
  padding-inline-start: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .16em;
  color: var(--mist-300);
  opacity: .72;
}

.rail__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.rail__item { display: block; }

.rail__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 8px;
  min-block-size: 44px;
  padding: 10px 10px 10px 12px;
  overflow: hidden;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.35;
  color: var(--mist-300);
  background-color: transparent;
  transition: color .18s var(--ease), background-color .18s var(--ease);
}

.rail__link::after {
  content: "";
  position: absolute;
  inset-block: 0;
  inset-inline-start: 0;
  inline-size: 3px;
  background-color: var(--cyan-500);
  transform: scaleY(0);
  transform-origin: center top;
  transition: transform .24s var(--ease);
}

.rail__link:hover {
  color: var(--paper-100);
  background-color: rgba(47, 224, 208, .07);
}

.rail__link:hover::after { transform: scaleY(1); }

.rail__link[aria-current="page"] {
  color: var(--paper-100);
  background-color: rgba(47, 224, 208, .1);
  border-block-end: 2px solid var(--cyan-500);
}

.rail__link[aria-current="page"]::after { transform: scaleY(1); }

.rail__num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .12em;
  color: var(--cyan-500);
}

.rail__link[aria-current="page"] .rail__num { color: var(--amber-400); }

.rail__label { min-inline-size: 0; }

.rail__actions {
  margin-block-start: auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-block-start: 16px;
  border-block-start: 1px solid var(--line-700);
}

/* 顶部滚动进度 */
.scroll-progress {
  position: fixed;
  inset-block-start: var(--bar-h);
  inset-inline: 0;
  z-index: 62;
  block-size: 3px;
  background-color: rgba(28, 61, 99, .5);
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  inline-size: 100%;
  block-size: 100%;
  background-image: linear-gradient(90deg, var(--cyan-500), var(--violet));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .08s linear;
}

/* ---------- 10. 页脚 ---------- */
.site-footer {
  position: relative;
  z-index: 2;
  margin-block-start: 72px;
  background-color: var(--ink-800);
  border-block-start: var(--frame) solid var(--line-700);
}

.footer__inner {
  display: grid;
  grid-template-columns: minmax(180px, 1fr) minmax(0, 2.4fr) minmax(220px, 1.3fr);
  gap: var(--gap);
  inline-size: 100%;
  max-inline-size: 1240px;
  margin-inline: auto;
  padding: 40px var(--edge);
}

.footer__name {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -.01em;
  color: var(--paper-100);
}

.footer__ver {
  margin: 4px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--violet);
}

.footer__line {
  margin-block-start: 12px;
  max-inline-size: 26ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist-300);
}

.footer__nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--gap);
}

.footer__col { min-inline-size: 0; }

.footer__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .16em;
  color: var(--cyan-500);
}

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

.footer__link {
  font-size: 15px;
  color: var(--mist-300);
  text-decoration: none;
  transition: color .16s var(--ease), padding-inline-start .16s var(--ease);
}

.footer__link:hover {
  color: var(--cyan-500);
  padding-inline-start: 4px;
}

.footer__list--contact { gap: 10px; }

.contact-item {
  display: flex;
  gap: 10px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--mist-300);
}

.contact-item__key {
  flex: 0 0 auto;
  min-inline-size: 34px;
  padding-block-start: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--cyan-500);
}

.contact-item__val {
  min-inline-size: 0;
  word-break: break-word;
}

.footer__tip {
  margin-block-start: 14px;
  padding-block-start: 12px;
  border-block-start: 1px solid var(--line-700);
  font-size: 13px;
  line-height: 1.65;
  color: var(--mist-300);
  opacity: .82;
}

.footer__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 24px;
  inline-size: 100%;
  max-inline-size: 1240px;
  margin-inline: auto;
  padding: 16px var(--edge) 32px;
  border-block-start: 1px solid var(--line-700);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--mist-300);
}

.footer__icp { margin: 0; }

.footer__copy {
  margin: 0;
  margin-inline-start: auto;
}

/* 返回顶部 */
.to-top {
  position: fixed;
  inset-block-end: 20px;
  inset-inline-end: 20px;
  z-index: 58;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-block-size: 44px;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .14em;
  color: var(--ink-900);
  background-color: var(--cyan-500);
  border: var(--frame) solid var(--ink-900);
  border-radius: var(--radius);
  box-shadow: 4px 4px 0 var(--shadow-ink);
  cursor: pointer;
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity .22s var(--ease), transform .22s var(--ease),
              background-color .18s var(--ease);
}

.to-top[data-visible] {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.to-top:hover { background-color: var(--amber-400); }

/* ---------- 11. 入场显现 ---------- */
html[data-reveal-ready] [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity .24s var(--ease), transform .24s var(--ease);
  transition-delay: var(--reveal-delay, 0ms);
}

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

/* ---------- 12. 响应式 ---------- */
@media (min-width: 1025px) {
  body { padding-inline-start: var(--rail-w); }

  .topbar__brand {
    inline-size: calc(var(--rail-w) - var(--edge));
  }
}

@media (max-width: 1024px) {
  :root {
    --edge: 24px;
  }

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

  .rail {
    inset-block-start: var(--bar-h);
    inline-size: min(320px, 84vw);
    visibility: hidden;
    transform: translateX(-102%);
    box-shadow: var(--shadow-hard);
    transition: transform .24s var(--ease), visibility 0s linear .24s;
  }

  .rail[data-open] {
    visibility: visible;
    transform: translateX(0);
    transition: transform .24s var(--ease), visibility 0s linear 0s;
  }

  body[data-nav-open]::after {
    content: "";
    position: fixed;
    inset: 0;
    z-index: 64;
    background-color: rgba(4, 16, 31, .66);
  }

  .footer__inner {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr);
  }

  .footer__contact {
    grid-column: 1 / -1;
  }
}

@media (max-width: 900px) {
  .quickbar__hint { display: none; }

  .quickbar__link {
    padding: 6px 12px 6px 14px;
  }

  .quickbar__label { font-size: 13px; }

  .footer__inner {
    grid-template-columns: minmax(0, 1fr);
    padding-block: 32px;
  }

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

@media (max-width: 640px) {
  :root {
    --edge: 18px;
    --bar-h: 52px;
    --gap: 18px;
  }

  body { font-size: 15px; }

  .topbar { gap: 10px; }

  .topbar__mark { font-size: 18px; }
  .topbar__name { display: none; }

  .nav-toggle__text { display: none; }

  .grid,
  .grid--8 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

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

  .footer__copy {
    margin-inline-start: 0;
  }

  .to-top {
    inset-block-end: 14px;
    inset-inline-end: 14px;
  }
}

/* ---------- 13. 无障碍：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;
    transition-delay: 0ms !important;
  }

  body::before { animation: none; }

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

  .btn:hover,
  .btn:active {
    transform: none;
    box-shadow: 4px 4px 0 var(--shadow-ink);
  }
}