/* =========================================================================
   KAIYUN 中文品牌专区 · 全站共享样式
   文件路径：/assets/site.css
   结构：1 变量与重置 · 2 基础排版 · 3 布局工具 · 4 通用组件
        5 品牌轨道（页头） · 6 页脚 · 7 响应式 · 8 可达性与动效
   ========================================================================= */

/* ---------- 1. 变量与重置 ---------- */
:root {
  --ink-900: #081613;
  --ink-800: #0E2A24;
  --ink-700: #143A31;
  --fog: #6E9C92;
  --amber: #D89B2B;
  --amber-soft: #E9AB3C;
  --coral: #E5674F;
  --rock: #5C6763;
  --moss: #3F6B57;
  --paper: #F2EBDD;
  --mist: #D9E3DE;

  --rail-w: 236px;
  --maxw: 1120px;
  --gutter: clamp(1.1rem, 3vw, 2.4rem);

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

  --dur: 150ms;
  --ease: cubic-bezier(.3, .7, .4, 1);
  --scroll-p: 0;

  --cut-lg: polygon(14px 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%, 0 14px);
  --cut-sm: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 78px;
}

body {
  margin: 0;
  padding-left: var(--rail-w);
  min-height: 100vh;
  background: var(--paper);
  color: var(--ink-800);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

button,
input,
select,
textarea { font: inherit; color: inherit; }

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

hr {
  border: 0;
  border-top: 1px solid rgba(92, 103, 99, .28);
  margin: 2rem 0;
}

/* ---------- 2. 基础排版 ---------- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-head);
  font-weight: 800;
  letter-spacing: -.012em;
  line-height: 1.24;
  margin: 0 0 .62em;
  color: inherit;
  text-wrap: balance;
}

h1 { font-size: clamp(1.72rem, 3.4vw, 2.6rem); }
h2 { font-size: clamp(1.32rem, 2.3vw, 1.78rem); }
h3 { font-size: clamp(1.08rem, 1.6vw, 1.26rem); }

p { margin: 0 0 1em; text-wrap: pretty; }
p:last-child { margin-bottom: 0; }

strong, b { font-weight: 700; }

a { color: inherit; }

small { font-size: .82em; }

.mono,
.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .01em;
}

.prose { max-width: 68ch; }
.prose > * + * { margin-top: 1.1em; }
.prose p { margin: 0; }
.prose h2,
.prose h3 { margin-top: 1.85em; }
.prose ul,
.prose ol { padding-left: 1.3em; }
.prose li + li { margin-top: .4em; }
.prose a {
  color: var(--moss);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: .18em;
  transition: color var(--dur) var(--ease), text-decoration-color var(--dur) var(--ease);
}
.prose a:hover { color: var(--ink-800); text-decoration-color: var(--amber); }
.prose blockquote {
  margin: 0;
  padding: .95rem 1.1rem;
  border-left: 3px solid var(--amber);
  background: rgba(217, 227, 222, .6);
  color: var(--rock);
}
.prose code {
  font-family: var(--font-mono);
  font-size: .88em;
  padding: .1em .36em;
  background: rgba(110, 156, 146, .18);
  color: var(--moss);
}

/* ---------- 3. 布局工具 ---------- */
.container {
  width: min(100% - (2 * var(--gutter)), var(--maxw));
  margin-inline: auto;
}

.grid { display: grid; gap: clamp(1rem, 2vw, 1.5rem); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.band {
  position: relative;
  padding-block: clamp(2.4rem, 5vw, 4rem);
}
.band--paper { background: var(--paper); }
.band--mist { background: var(--mist); }
.band--ink { background: var(--ink-800); color: var(--paper); }

.slant-top { clip-path: polygon(0 30px, 100% 0, 100% 100%, 0 100%); }
.slant-bottom { clip-path: polygon(0 0, 100% 0, 100% 100%, 0 calc(100% - 30px)); }

.on-dark { color: var(--mist); }
.on-dark h1,
.on-dark h2,
.on-dark h3 { color: var(--paper); }
.on-dark .kicker { color: var(--fog); }
.on-dark a:not(.btn) { color: var(--mist); }

/* ---------- 4. 通用组件 ---------- */
.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .35rem 1rem;
  margin-bottom: clamp(1.2rem, 2.4vw, 1.8rem);
  padding-bottom: .9rem;
  border-bottom: 1px solid rgba(92, 103, 99, .26);
}
.section-head h1,
.section-head h2 { margin: 0; }

.kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--moss);
}

.sec-index {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--amber);
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .72rem 1.15rem;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: .92rem;
  line-height: 1.2;
  text-decoration: none;
  border: 1px solid transparent;
  background: none;
  color: var(--ink-900);
  cursor: pointer;
  clip-path: var(--cut-sm);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease),
              border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.btn:active { transform: translateY(1px); }

.btn--solid { background: var(--ink-800); color: var(--paper); }
.btn--solid:hover { background: var(--moss); color: #fff; }

.btn--amber { background: var(--amber); color: var(--ink-900); }
.btn--amber:hover { background: var(--amber-soft); }

.btn--ghost { border-color: var(--fog); color: var(--ink-800); background: transparent; }
.btn--ghost:hover { border-color: var(--amber); background: rgba(216, 155, 43, .14); color: var(--ink-900); }

.btn--ghost-light { border-color: rgba(217, 227, 222, .5); color: var(--paper); background: transparent; }
.btn--ghost-light:hover { border-color: var(--amber); color: var(--amber); }

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .22rem .55rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .06em;
  line-height: 1.5;
  background: var(--mist);
  color: var(--rock);
  clip-path: var(--cut-sm);
}
.tag--amber { background: rgba(216, 155, 43, .2); color: #855c0d; }
.tag--coral { background: rgba(229, 103, 79, .18); color: #a33522; }
.tag--moss { background: rgba(63, 107, 87, .16); color: var(--moss); }

/* 面包屑 */
.breadcrumbs {
  margin: 0 0 1.4rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .05em;
  color: var(--rock);
}
.breadcrumbs ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
}
.breadcrumbs li + li::before {
  content: "/";
  margin-right: .45rem;
  color: var(--fog);
}
.breadcrumbs a { text-decoration: none; }
.breadcrumbs a:hover { color: var(--moss); text-decoration: underline; text-underline-offset: .2em; }

/* 表格 */
.table-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border: 1px solid rgba(92, 103, 99, .24);
  background: var(--paper);
}
.data-table {
  width: 100%;
  min-width: 520px;
  border-collapse: collapse;
  font-size: .9rem;
}
.data-table caption {
  caption-side: top;
  text-align: left;
  padding: .7rem .8rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
  color: var(--rock);
  background: rgba(217, 227, 222, .55);
}
.data-table th,
.data-table td {
  padding: .72rem .8rem;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid rgba(92, 103, 99, .2);
}
.data-table thead th {
  background: var(--ink-800);
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: .74rem;
  font-weight: 600;
  letter-spacing: .08em;
  border-bottom: 0;
}
.data-table tbody tr:nth-child(even) { background: rgba(217, 227, 222, .42); }
.data-table tbody tr:hover { background: rgba(216, 155, 43, .14); }
.data-table td.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--ink-800);
}
.data-table tfoot td {
  font-family: var(--font-mono);
  font-size: .76rem;
  color: var(--rock);
  background: rgba(110, 156, 146, .12);
}

/* 图片容器基础规则（页面阶段插入 img） */
.media-frame {
  position: relative;
  width: 100%;
  overflow: hidden;
  background:
    repeating-radial-gradient(circle at 24% 18%, rgba(217, 227, 222, .16) 0 1px, transparent 1px 20px),
    linear-gradient(155deg, var(--ink-800) 0%, var(--moss) 58%, var(--fog) 100%);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.media-frame--ratio { aspect-ratio: 16 / 10; }
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame--empty::after {
  content: attr(data-placeholder);
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 1rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(242, 235, 221, .62);
}

.media-frame__caption {
  position: absolute;
  inset-inline: 0;
  bottom: 0;
  padding: 1.6rem .9rem .7rem;
  background: linear-gradient(0deg, rgba(8, 22, 19, .88), transparent);
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .06em;
}

/* ---------- 5. 品牌轨道（页头） ---------- */
.skip-link {
  position: fixed;
  top: 0;
  left: 50%;
  z-index: 300;
  transform: translate(-50%, -160%);
  padding: .62rem 1.15rem;
  background: var(--amber);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .06em;
  text-decoration: none;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 10px 100%, 0 calc(100% - 10px));
  transition: transform var(--dur) var(--ease);
}
.skip-link:focus-visible { transform: translate(-50%, 0); }

.brand-rail {
  position: fixed;
  inset-block-start: 0;
  inset-block-end: 0;
  inset-inline-start: 0;
  z-index: 90;
  width: var(--rail-w);
  display: flex;
  flex-direction: column;
  padding: 22px 18px 18px;
  background-color: #0B231E;
  background-image: linear-gradient(180deg, #0E2A24 0%, #0B231E 54%, #081613 100%);
  color: var(--mist);
  border-inline-end: 1px solid rgba(110, 156, 146, .3);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: rgba(110, 156, 146, .45) transparent;
}

.brand-rail::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    repeating-radial-gradient(circle at 14% 6%,
      rgba(110, 156, 146, .22) 0 1px,
      transparent 1px 24px),
    repeating-radial-gradient(circle at 96% 96%,
      rgba(216, 155, 43, .12) 0 1px,
      transparent 1px 30px);
  opacity: .55;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 78%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 78%);
}

/* 品牌区 */
.rail-head {
  position: relative;
  z-index: 2;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding-bottom: 18px;
  border-bottom: 1px solid rgba(217, 227, 222, .16);
}

.rail-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1 1 100%;
  min-width: 0;
  text-decoration: none;
  color: inherit;
}

.rail-brand-mark {
  flex: 0 0 auto;
  width: 28px;
  height: 28px;
  border: 1px solid rgba(216, 155, 43, .7);
  background:
    linear-gradient(135deg, transparent 44%, var(--amber) 44% 56%, transparent 56%),
    linear-gradient(160deg, var(--moss), var(--ink-700));
  clip-path: polygon(7px 0, 100% 0, 100% calc(100% - 7px), calc(100% - 7px) 100%, 0 100%, 0 7px);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.rail-brand:hover .rail-brand-mark { border-color: var(--amber); }

.rail-brand-text { display: block; min-width: 0; }

.rail-brand-name {
  display: block;
  font-family: var(--font-head);
  font-size: 1.06rem;
  font-weight: 800;
  letter-spacing: .02em;
  line-height: 1.25;
  color: var(--paper);
  transition: color var(--dur) var(--ease);
}
.rail-brand:hover .rail-brand-name { color: var(--amber); }

.rail-brand-line {
  display: block;
  font-family: var(--font-mono);
  font-size: .64rem;
  letter-spacing: .16em;
  line-height: 1.5;
  color: var(--fog);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.rail-version {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  line-height: 1.5;
  padding: .18rem .5rem;
  color: var(--ink-900);
  background: var(--amber);
  clip-path: polygon(6px 0, 100% 0, 100% calc(100% - 6px), calc(100% - 6px) 100%, 0 100%, 0 6px);
}

/* 移动端汉堡 */
.rail-toggle {
  display: none;
  align-items: center;
  gap: .5rem;
  flex: 0 0 auto;
  margin-inline-start: auto;
  padding: .44rem .68rem;
  border: 1px solid rgba(217, 227, 222, .38);
  background: transparent;
  color: var(--mist);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  clip-path: var(--cut-sm);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease),
              background-color var(--dur) var(--ease);
}
.rail-toggle:hover {
  border-color: var(--amber);
  color: var(--amber);
  background: rgba(216, 155, 43, .1);
}

.rail-toggle-bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: background-color var(--dur) var(--ease);
}
.rail-toggle-bars::before,
.rail-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease);
}
.rail-toggle-bars::before { top: -5px; }
.rail-toggle-bars::after { top: 5px; }

.rail-toggle[aria-expanded="true"] .rail-toggle-bars { background: transparent; }
.rail-toggle[aria-expanded="true"] .rail-toggle-bars::before { transform: translateY(5px) rotate(45deg); }
.rail-toggle[aria-expanded="true"] .rail-toggle-bars::after { transform: translateY(-5px) rotate(-45deg); }

/* 导航 */
.rail-nav {
  position: relative;
  z-index: 1;
  flex: 1 1 auto;
  padding: 18px 0 12px;
}

.rail-nav-label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: .64rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(217, 227, 222, .58);
}

.rail-list {
  list-style: none;
  display: grid;
  gap: 2px;
  margin: 0;
  padding: 0;
}

.rail-link {
  display: flex;
  align-items: baseline;
  gap: .62rem;
  padding: .52rem .55rem;
  color: var(--mist);
  text-decoration: none;
  font-size: .93rem;
  line-height: 1.45;
  border-left: 3px solid transparent;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}
.rail-link:hover {
  background: rgba(110, 156, 146, .16);
  color: #fff;
  border-left-color: var(--amber);
}

.rail-link[aria-current="page"] {
  background: linear-gradient(90deg, rgba(63, 107, 87, .62), rgba(63, 107, 87, .1));
  color: var(--paper);
  border-left-color: var(--amber);
}

.rail-index {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .06em;
  color: var(--fog);
  opacity: .78;
  transition: color var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.rail-link:hover .rail-index { color: var(--amber); opacity: 1; }
.rail-link[aria-current="page"] .rail-index { color: var(--amber); opacity: 1; }

.rail-text { min-width: 0; }

.rail-nav-cta {
  display: none;
  align-items: center;
  justify-content: space-between;
  gap: .5rem;
  margin-top: .9rem;
  padding: .72rem .8rem;
  text-decoration: none;
  font-weight: 700;
  font-size: .92rem;
  color: var(--ink-900);
  background: var(--amber);
  clip-path: var(--cut-sm);
  transition: background-color var(--dur) var(--ease);
}
.rail-nav-cta:hover { background: var(--amber-soft); }

.rail-arrow {
  font-family: var(--font-mono);
  font-size: .95em;
  transition: transform var(--dur) var(--ease);
}
.rail-cta:hover .rail-arrow,
.rail-nav-cta:hover .rail-arrow { transform: translateX(3px); }

/* 轨道底部 */
.rail-foot {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 10px;
  padding-top: 16px;
  border-top: 1px solid rgba(217, 227, 222, .16);
}

.rail-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .5rem;
  padding: .72rem .8rem;
  text-decoration: none;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: .9rem;
  color: var(--ink-900);
  background: var(--amber);
  clip-path: var(--cut-sm);
  transition: background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.rail-cta:hover { background: var(--amber-soft); }
.rail-cta:active { transform: translateY(1px); }

.rail-cta-label { min-width: 0; }

.rail-meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: .67rem;
  line-height: 1.7;
  letter-spacing: .02em;
  color: rgba(217, 227, 222, .6);
}
.rail-meta b { color: var(--amber); font-weight: 700; }

/* 阅读进度刻度线 */
.rail-progress {
  position: absolute;
  inset-block: 0;
  inset-inline-end: 0;
  z-index: 3;
  width: 3px;
  background: rgba(110, 156, 146, .2);
  pointer-events: none;
}
.rail-progress-bar {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, var(--amber) 0%, var(--moss) 100%);
  transform: scaleY(var(--scroll-p));
  transform-origin: top center;
}

/* ---------- 6. 页脚 ---------- */
.site-foot {
  position: relative;
  margin-top: clamp(2.4rem, 6vw, 4.6rem);
  padding: clamp(2.6rem, 4.6vw, 3.8rem) 0 1.6rem;
  background-color: var(--ink-900);
  background-image: linear-gradient(180deg, #0B231E 0%, #081613 100%);
  color: var(--mist);
  overflow: hidden;
}

.site-foot::before {
  content: "";
  position: absolute;
  inset-inline: 0;
  top: 0;
  height: 6px;
  background: repeating-linear-gradient(112deg,
    var(--amber) 0 16px,
    var(--moss) 16px 32px,
    transparent 32px 48px);
  opacity: .92;
}

.site-foot::after {
  content: "";
  position: absolute;
  inset-inline-end: -120px;
  bottom: -190px;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  pointer-events: none;
  background: repeating-radial-gradient(circle,
    rgba(110, 156, 146, .16) 0 1px,
    transparent 1px 26px);
}

.foot-inner {
  position: relative;
  z-index: 1;
  width: min(100% - (2 * var(--gutter)), var(--maxw));
  margin-inline: auto;
}

.foot-grid {
  display: grid;
  grid-template-columns: minmax(250px, 1.5fr) repeat(3, minmax(0, .82fr)) minmax(210px, 1fr);
  gap: clamp(1.4rem, 2.6vw, 2.4rem);
  padding-bottom: clamp(1.6rem, 3vw, 2.2rem);
  border-bottom: 1px solid rgba(217, 227, 222, .16);
}

.foot-brand { min-width: 0; }

.foot-mark {
  display: flex;
  align-items: center;
  gap: .55rem;
  margin: 0 0 .7rem;
  font-family: var(--font-head);
  font-size: 1.18rem;
  font-weight: 800;
  letter-spacing: .02em;
  color: var(--paper);
}

.foot-version {
  font-family: var(--font-mono);
  font-size: .66rem;
  font-weight: 700;
  letter-spacing: .1em;
  line-height: 1.5;
  padding: .14rem .44rem;
  color: var(--ink-900);
  background: var(--amber);
  clip-path: polygon(5px 0, 100% 0, 100% calc(100% - 5px), calc(100% - 5px) 100%, 0 100%, 0 5px);
}

.foot-summary {
  margin: 0;
  max-width: 32ch;
  font-size: .88rem;
  line-height: 1.8;
  color: rgba(217, 227, 222, .74);
}

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

.foot-col-title {
  margin: 0 0 .85rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--amber);
}

.foot-links {
  list-style: none;
  display: grid;
  gap: .55rem;
  margin: 0;
  padding: 0;
}

.foot-links a,
.foot-contact-list a {
  display: inline;
  color: var(--mist);
  text-decoration: none;
  font-size: .9rem;
  line-height: 1.7;
  padding-bottom: 2px;
  background-image: linear-gradient(var(--amber), var(--amber));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0% 1px;
  transition: background-size var(--dur) var(--ease), color var(--dur) var(--ease);
}
.foot-links a:hover,
.foot-contact-list a:hover {
  color: #fff;
  background-size: 100% 1px;
}

.foot-contact { min-width: 0; }

.foot-contact-list {
  list-style: none;
  display: grid;
  gap: .58rem;
  margin: 0;
  padding: 0;
  font-size: .86rem;
  line-height: 1.7;
  color: rgba(217, 227, 222, .78);
}
.foot-contact-list li {
  display: grid;
  grid-template-columns: 2.6rem minmax(0, 1fr);
  gap: .5rem;
  align-items: start;
}
.foot-contact-list a { overflow-wrap: anywhere; }

.foot-key {
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .08em;
  color: var(--fog);
  padding-top: .12em;
}

.foot-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .7rem 1.6rem;
  padding-top: 1.35rem;
  font-family: var(--font-mono);
  font-size: .71rem;
  letter-spacing: .03em;
  color: rgba(217, 227, 222, .6);
}
.foot-copy { margin: 0; }
.foot-icp { margin: 0; }

.foot-legal-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: .5rem 1.1rem;
  margin: 0;
  padding: 0;
}
.foot-legal-links a {
  color: rgba(217, 227, 222, .72);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}
.foot-legal-links a:hover { color: var(--amber); }

/* ---------- 7. 响应式 ---------- */
@media (max-width: 1180px) {
  .foot-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  }
  .foot-brand { grid-column: 1 / -1; }
  .foot-summary { max-width: 46ch; }
}

@media (max-width: 900px) {
  html { scroll-padding-top: 84px; }

  body {
    padding-left: 0;
    padding-top: 64px;
  }

  .brand-rail {
    inset-block-start: 0;
    inset-block-end: auto;
    inset-inline: 0;
    width: auto;
    padding: 10px 16px;
    overflow: visible;
    border-inline-end: 0;
    border-bottom: 1px solid rgba(110, 156, 146, .34);
    box-shadow: 0 10px 26px rgba(8, 22, 19, .28);
  }

  .brand-rail::before { opacity: .3; }

  .rail-head {
    padding-bottom: 0;
    border-bottom: 0;
    gap: 10px;
  }

  .rail-brand { flex: 1 1 140px; }
  .rail-brand-name { font-size: 1rem; }
  .rail-brand-line { font-size: .6rem; letter-spacing: .12em; }
  .rail-brand-mark { width: 24px; height: 24px; }

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

  .rail-nav {
    position: absolute;
    inset-inline: 0;
    top: 100%;
    flex: 0 0 auto;
    max-height: 0;
    padding: 0 16px;
    overflow: hidden;
    background: #0B231E;
    border-bottom: 2px solid var(--amber);
    box-shadow: 0 22px 34px rgba(8, 22, 19, .48);
    transition: max-height 180ms var(--ease), padding 180ms var(--ease);
  }

  .rail-nav[data-open="true"] {
    max-height: min(72vh, 540px);
    padding: 14px 16px 18px;
    overflow-y: auto;
  }

  .rail-nav-label { display: none; }

  .rail-list { gap: 0; }
  .rail-list li + li { border-top: 1px solid rgba(217, 227, 222, .12); }
  .rail-link {
    padding: .8rem .4rem;
    font-size: 1rem;
    border-left-width: 0;
    border-inline-start: 3px solid transparent;
  }
  .rail-link:hover,
  .rail-link[aria-current="page"] { border-inline-start-color: var(--amber); }
  .rail-index { font-size: .74rem; }

  .rail-nav-cta { display: flex; }

  .rail-foot { display: none; }

  .rail-progress {
    inset-block: auto;
    inset-inline: 0;
    bottom: -1px;
    width: auto;
    height: 3px;
  }
  .rail-progress-bar {
    transform: scaleX(var(--scroll-p));
    transform-origin: left center;
  }

  .grid--2,
  .grid--3 { grid-template-columns: minmax(0, 1fr); }

  .foot-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .site-foot { margin-top: 2.4rem; }
}

@media (max-width: 620px) {
  .foot-grid { grid-template-columns: minmax(0, 1fr); }
  .foot-brand { grid-column: auto; }
  .foot-legal { flex-direction: column; align-items: flex-start; gap: .5rem; }
  .foot-contact-list li { grid-template-columns: 2.4rem minmax(0, 1fr); }
}

@media (max-width: 380px) {
  .rail-toggle-text { display: none; }
  .rail-brand-line { display: none; }
}

/* ---------- 8. 可达性与动效 ---------- */
:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 3px;
  border-radius: 2px;
}
.brand-rail :where(a, button):focus-visible {
  outline-color: var(--amber);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .rail-progress-bar { transition: none !important; }
}