/* ============================================================
   币游平台站 · 共享外壳样式 /assets/site.css
   结构：重置 → 变量 → 中文排版 → 容器与工具类 → 页头 → 页脚
        → 通用按钮 → 通用组件 → 响应式 → 动效与无障碍
   ============================================================ */

/* ---------- 1. 重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  background: #0B1F2A;
}

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

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

button {
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

a { color: inherit; text-decoration: none; }

ul, ol { list-style: none; padding: 0; }

/* ---------- 2. 变量 ---------- */
:root {
  /* 色彩 */
  --c-ink: #0B1F2A;
  --c-ink-deep: #061119;
  --c-mist: #F4F1EA;
  --c-paper: #CFC7B8;
  --c-celadon: #2F7D6B;
  --c-amber: #E8A63C;
  --c-coral: #E06B52;
  --c-steel: #7C97A3;
  --c-black: #050708;
  --c-white: #FFFFFF;

  /* 版本强调色（新版青瓷绿 / 旧版珊瑚红） */
  --accent: var(--c-celadon);
  --accent-on: var(--c-white);

  /* 字体 */
  --font-display: 'Source Han Sans SC Heavy', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-body: 'Source Han Sans SC', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-num: 'DIN Condensed', 'Oswald', 'Bebas Neue', sans-serif;

  /* 尺寸 */
  --shell: 1320px;
  --gutter: clamp(16px, 4.2vw, 48px);

  /* 粗野主义线条与阴影 */
  --line: 2px;
  --line-thick: 3px;
  --shadow: 6px 6px 0 var(--c-black);
  --shadow-sm: 4px 4px 0 var(--c-black);

  /* 动效 */
  --ease: cubic-bezier(.2, .7, .3, 1);
  --dur: 220ms;
  --dur-fast: 180ms;
}

html[data-version="old"] {
  --accent: var(--c-coral);
  --accent-on: var(--c-ink);
}

/* ---------- 3. 中文排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-mist);
  background: var(--c-ink);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  letter-spacing: 0.01em;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.015em;
  text-wrap: balance;
}

h1 { font-size: clamp(2rem, 5.4vw, 4.5rem); }
h2 { font-size: clamp(1.5rem, 2.9vw, 2.5rem); }
h3 { font-size: clamp(1.125rem, 1.6vw, 1.375rem); }
h4 { font-size: 1rem; letter-spacing: 0.02em; }

h5, h6 {
  font-family: var(--font-body);
  font-weight: 700;
  line-height: 1.4;
}

p { text-wrap: pretty; }

p + p { margin-top: 0.85em; }

strong, b { font-weight: 700; }

small { font-size: 0.8125rem; line-height: 1.6; }

/* ---------- 4. 容器与工具类 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  padding-block: clamp(40px, 6vw, 88px);
}

.u-visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.grid {
  display: grid;
  gap: clamp(16px, 2.2vw, 28px);
}

.num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
  line-height: 1;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-num);
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--c-steel);
}

/* ---------- 5. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  left: 16px;
  top: 16px;
  z-index: 999;
  transform: translateY(-240%);
  display: inline-block;
  padding: 10px 18px;
  background: var(--c-amber);
  color: var(--c-black);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.875rem;
  border: var(--line) solid var(--c-black);
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur-fast) var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  transform: translateY(0);
  outline: 3px solid var(--c-white);
  outline-offset: 2px;
}

/* ---------- 6. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 200;
  background: var(--c-ink);
  border-bottom: var(--line-thick) solid var(--c-black);
}

/* 6.1 命令栏 */
.command-bar {
  background: var(--c-ink-deep);
  border-bottom: 1px solid rgba(207, 199, 184, 0.18);
}

.command-bar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(12px, 2.4vw, 32px);
  min-height: 40px;
  padding-block: 7px;
  font-size: 0.75rem;
  letter-spacing: 0.05em;
}

.command-bar__meta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  margin: 0;
}

.command-bar__label {
  color: var(--c-steel);
  letter-spacing: 0.12em;
}

.command-bar__value {
  color: var(--c-paper);
  font-weight: 700;
}

.command-bar__dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  background: var(--accent);
  border: 1px solid var(--c-black);
  transition: background-color var(--dur) var(--ease);
}

.command-bar__util {
  margin: 0;
  color: var(--c-steel);
  letter-spacing: 0.14em;
  white-space: nowrap;
}

/* 6.2 版本切换 */
.version-toggle {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 4px 11px 4px 7px;
  background: rgba(244, 241, 234, 0.06);
  border: 1px solid rgba(207, 199, 184, 0.38);
  color: var(--c-mist);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  line-height: 1.4;
  transition:
    background-color var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    color var(--dur) var(--ease);
}

.version-toggle:hover {
  border-color: var(--accent);
  color: var(--c-white);
}

.version-toggle__pip {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  background: var(--accent);
  transition: background-color var(--dur) var(--ease);
}

.version-toggle__text--old { display: none; }

html[data-version="old"] .version-toggle__text--new { display: none; }
html[data-version="old"] .version-toggle__text--old { display: inline; }
html[data-version="old"] .version-toggle { border-color: rgba(224, 107, 82, 0.55); }

/* 6.3 品牌与主导航 */
.masthead { background: var(--c-ink); }

.masthead__inner {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2.4vw, 32px);
  padding-block: clamp(11px, 1.5vw, 16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  margin-right: auto;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  background: var(--c-amber);
  color: var(--c-black);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.375rem;
  line-height: 1;
  border: var(--line) solid var(--c-black);
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}

.brand:hover .brand__mark {
  transform: translate(-1px, -1px);
  box-shadow: 6px 6px 0 var(--c-black);
}

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

.brand__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.0625rem;
  letter-spacing: -0.01em;
  color: var(--c-white);
  line-height: 1.2;
}

.brand__suffix {
  font-family: var(--font-num);
  font-size: 0.6875rem;
  letter-spacing: 0.22em;
  color: var(--c-steel);
  line-height: 1;
}

.site-nav__list {
  display: flex;
  align-items: stretch;
  gap: 2px;
  flex-wrap: nowrap;
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 9px 12px 11px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.9375rem;
  letter-spacing: 0.01em;
  color: var(--c-mist);
  border-bottom: 3px solid transparent;
  white-space: nowrap;
  transition:
    color var(--dur-fast) var(--ease),
    background-color var(--dur-fast) var(--ease),
    border-color var(--dur-fast) var(--ease);
}

.site-nav__index {
  font-family: var(--font-num);
  font-size: 0.625rem;
  letter-spacing: 0.1em;
  color: var(--c-steel);
  transition: color var(--dur-fast) var(--ease);
}

.site-nav__link:hover {
  color: var(--c-white);
  background: rgba(244, 241, 234, 0.06);
}

.site-nav__link:focus-visible {
  outline: 3px solid var(--c-amber);
  outline-offset: -3px;
}

.site-nav__link[aria-current="page"] {
  color: var(--c-white);
  border-bottom-color: var(--accent);
}

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

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

/* 6.4 移动菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 13px;
  background: var(--c-ink-deep);
  color: var(--c-mist);
  border: var(--line) solid var(--c-paper);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  line-height: 1.2;
  transition:
    background-color var(--dur-fast) var(--ease),
    color var(--dur-fast) var(--ease),
    border-color var(--dur-fast) var(--ease);
}

.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  gap: 3px;
  width: 16px;
}

.nav-toggle__bars > span {
  display: block;
  height: 2px;
  width: 100%;
  background: currentColor;
}

.nav-toggle[aria-expanded="true"] {
  background: var(--accent);
  color: var(--accent-on);
  border-color: var(--c-black);
}

/* 6.5 滚动进度 */
.scroll-progress {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  background: var(--c-amber);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 90ms linear;
  pointer-events: none;
}

/* ---------- 7. 页脚 ---------- */
.site-footer {
  background: var(--c-ink-deep);
  color: var(--c-paper);
  border-top: var(--line-thick) solid var(--c-black);
}

.footer-shell {
  padding-block: clamp(36px, 5vw, 64px) clamp(20px, 2.4vw, 28px);
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(220px, 1.5fr) repeat(3, minmax(130px, 1fr));
  gap: clamp(24px, 3.6vw, 52px);
  padding-bottom: clamp(28px, 3.6vw, 44px);
  border-bottom: 1px solid rgba(207, 199, 184, 0.2);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 16px;
}

.footer-lockup {
  display: inline-flex;
  align-items: center;
  gap: 11px;
}

.footer-lockup__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  flex: 0 0 auto;
  background: var(--c-amber);
  color: var(--c-black);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.125rem;
  line-height: 1;
  border: var(--line) solid var(--c-black);
}

.footer-lockup__text {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.footer-lockup__text b {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
  color: var(--c-white);
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.footer-lockup__text small {
  font-family: var(--font-num);
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  color: var(--c-steel);
  line-height: 1.2;
}

.footer-brand__note {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--c-paper);
  max-width: 30ch;
}

.footer-col__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--c-amber);
  margin-bottom: 14px;
  line-height: 1.3;
}

.footer-col__list {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-col__link {
  display: inline-block;
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--c-paper);
  border-bottom: 1px solid transparent;
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.footer-col__link:hover {
  color: var(--c-white);
  border-bottom-color: var(--accent);
}

/* 7.2 联系信息带 */
.footer-contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 14px clamp(18px, 3vw, 40px);
  padding-block: clamp(22px, 3vw, 30px);
  border-bottom: 1px solid rgba(207, 199, 184, 0.2);
}

.footer-contact__row {
  display: flex;
  flex-direction: column;
  gap: 7px;
  min-width: 0;
}

.footer-contact__row--wide { min-width: 0; }

.footer-contact__label {
  font-family: var(--font-num);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: var(--c-steel);
  line-height: 1.2;
}

.footer-contact__value {
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--c-mist);
  word-break: break-word;
}

.footer-contact__note {
  grid-column: 1 / -1;
  margin: 0;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--c-steel);
  max-width: 78ch;
}

/* 7.3 复制按钮 */
.copy-chip {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  max-width: 100%;
  padding: 8px 12px;
  background: rgba(244, 241, 234, 0.05);
  border: var(--line) solid rgba(207, 199, 184, 0.34);
  color: var(--c-mist);
  text-align: left;
  transition:
    background-color var(--dur-fast) var(--ease),
    border-color var(--dur-fast) var(--ease),
    color var(--dur-fast) var(--ease);
}

.copy-chip:hover {
  border-color: var(--accent);
  color: var(--c-white);
}

.copy-chip__value {
  font-family: var(--font-num);
  font-size: 1.0625rem;
  letter-spacing: 0.02em;
  line-height: 1.3;
  word-break: break-all;
}

.copy-chip__state {
  flex: 0 0 auto;
  padding: 2px 8px;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--c-black);
  background: var(--c-amber);
  line-height: 1.5;
}

.copy-chip[data-copy-state="copied"] {
  border-color: var(--accent);
}

.copy-chip[data-copy-state="copied"] .copy-chip__state {
  background: var(--accent);
  color: var(--accent-on);
}

/* 7.4 版权与备案带 */
.footer-base {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px 24px;
  padding-top: clamp(18px, 2.4vw, 24px);
}

.footer-base__legal {
  margin: 0;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  line-height: 1.7;
  color: var(--c-steel);
}

/* ---------- 8. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.875rem;
  letter-spacing: 0.02em;
  line-height: 1.3;
  text-align: center;
  border: var(--line) solid var(--c-black);
  cursor: pointer;
  transition:
    transform var(--dur-fast) var(--ease),
    box-shadow var(--dur-fast) var(--ease),
    background-color var(--dur-fast) var(--ease),
    color var(--dur-fast) var(--ease),
    border-color var(--dur-fast) var(--ease);
}

.btn--solid {
  background: var(--accent);
  color: var(--accent-on);
  box-shadow: var(--shadow-sm);
}

.btn--solid:hover {
  transform: translate(-1px, -1px);
  box-shadow: 6px 6px 0 var(--c-black);
}

.btn--ghost {
  background: transparent;
  color: var(--c-mist);
  border-color: var(--c-paper);
}

.btn--ghost:hover {
  background: rgba(244, 241, 234, 0.07);
  border-color: var(--c-white);
  color: var(--c-white);
}

.btn--amber {
  background: var(--c-amber);
  color: var(--c-black);
  box-shadow: var(--shadow-sm);
}

.btn--amber:hover {
  transform: translate(-1px, -1px);
  box-shadow: 6px 6px 0 var(--c-black);
}

.btn--small {
  padding: 9px 14px;
  font-size: 0.8125rem;
}

/* ---------- 9. 通用组件 ---------- */
/* 9.1 面板 */
.panel {
  position: relative;
  background: var(--c-ink);
  color: var(--c-mist);
  border: var(--line-thick) solid var(--c-black);
  box-shadow: var(--shadow);
  padding: clamp(20px, 3vw, 40px);
}

.panel--light {
  background: var(--c-mist);
  color: var(--c-ink);
}

.panel--deep {
  background: var(--c-ink-deep);
  color: var(--c-mist);
}

.panel__index {
  display: block;
  font-family: var(--font-num);
  font-size: clamp(2rem, 4vw, 3.25rem);
  line-height: 0.9;
  letter-spacing: 0.01em;
  color: var(--c-amber);
  margin-bottom: 10px;
}

.panel__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.25rem, 2.2vw, 1.875rem);
  letter-spacing: -0.015em;
  line-height: 1.2;
  margin-bottom: 12px;
}

.panel__body {
  max-width: 68ch;
  font-size: 1rem;
  line-height: 1.75;
}

.panel--light .panel__body { color: #1B3442; }

/* 9.2 卡片 */
.card {
  background: var(--c-ink-deep);
  color: var(--c-mist);
  border: var(--line) solid var(--c-black);
  box-shadow: var(--shadow-sm);
  padding: clamp(16px, 2vw, 24px);
}

/* 9.3 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1.5;
  border: var(--line) solid currentColor;
  white-space: nowrap;
}

.tag--new { color: var(--c-celadon); }
.tag--old { color: var(--c-coral); }
.tag--price { color: var(--c-amber); }

/* 9.4 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: clamp(14px, 2vw, 20px);
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--c-steel);
}

.breadcrumbs__link {
  color: var(--c-paper);
  border-bottom: 1px solid transparent;
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.breadcrumbs__link:hover {
  color: var(--c-white);
  border-bottom-color: var(--accent);
}

.breadcrumbs__sep {
  color: var(--c-steel);
  font-family: var(--font-num);
}

.breadcrumbs__current {
  color: var(--c-mist);
  font-weight: 700;
}

/* 9.5 响应式图片容器 */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  background: var(--c-ink-deep);
  border: var(--line-thick) solid var(--c-black);
  box-shadow: var(--shadow-sm);
  aspect-ratio: 4 / 3;
}

.media-frame > img,
.media-frame > picture,
.media-frame > picture > img,
.media-frame > svg,
.media-frame > video {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  max-width: 100%;
  padding: 6px 12px;
  background: var(--c-black);
  color: var(--c-mist);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  line-height: 1.5;
}

/* 9.6 可展开内容组 */
.accordion {
  border-top: var(--line) solid var(--c-black);
}

.accordion__item {
  border-bottom: var(--line) solid var(--c-black);
}

.accordion__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 16px 4px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
  letter-spacing: 0.01em;
  line-height: 1.45;
  text-align: left;
  color: inherit;
  transition: color var(--dur-fast) var(--ease);
}

.accordion__trigger:hover { color: var(--accent); }

.accordion__icon {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  border: var(--line) solid currentColor;
  font-family: var(--font-num);
  font-size: 0.875rem;
  line-height: 1;
  transition: transform var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}

.accordion__trigger[aria-expanded="true"] .accordion__icon {
  transform: rotate(45deg);
  color: var(--accent);
}

.accordion__panel {
  display: none;
  padding: 0 4px 20px;
  font-size: 0.9375rem;
  line-height: 1.8;
}

.accordion__panel[data-open] { display: block; }

/* ---------- 10. 响应式 ---------- */
@media (max-width: 1180px) {
  .site-nav__link {
    padding-inline: 9px;
    font-size: 0.875rem;
  }
  .site-nav__index { display: none; }
}

@media (max-width: 1023px) {
  .masthead__inner { flex-wrap: nowrap; }

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

  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--c-ink-deep);
    border-top: 1px solid rgba(207, 199, 184, 0.2);
    border-bottom: var(--line-thick) solid var(--c-black);
    padding: 8px var(--gutter) 22px;
    box-shadow: 0 12px 0 rgba(5, 7, 8, 0.42);
  }

  .site-nav[data-open] { display: block; }

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

  .site-nav__item + .site-nav__item {
    border-top: 1px solid rgba(207, 199, 184, 0.14);
  }

  .site-nav__link {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 15px 6px 15px 12px;
    border-bottom: 0;
    border-left: 3px solid transparent;
    font-size: 1rem;
  }

  .site-nav__index {
    display: inline-block;
    font-size: 0.6875rem;
  }

  .site-nav__link[aria-current="page"] {
    border-bottom-color: transparent;
    border-left-color: var(--accent);
    background: rgba(244, 241, 234, 0.05);
  }

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

  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  .command-bar__util { display: none; }
}

@media (max-width: 720px) {
  .masthead__actions .btn--ghost { display: none; }

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

  .footer-base {
    flex-direction: column-reverse;
    align-items: flex-start;
    gap: 6px;
  }
}

@media (max-width: 560px) {
  .masthead__actions .btn--solid { display: none; }

  .command-bar__meta--time .command-bar__label { display: none; }

  .command-bar__inner {
    font-size: 0.6875rem;
    gap: 10px;
  }

  .brand__mark {
    width: 38px;
    height: 38px;
    font-size: 1.125rem;
    box-shadow: 3px 3px 0 var(--c-black);
  }

  .brand__name { font-size: 0.9375rem; }

  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
  }

  .panel { box-shadow: var(--shadow-sm); }

  .copy-chip__value { font-size: 0.9375rem; }
}

/* ---------- 11. 动效与无障碍 ---------- */
[data-reveal] {
  opacity: 1;
  transform: none;
}

html.js [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition:
    opacity var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

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

:focus-visible {
  outline: 3px solid var(--c-amber);
  outline-offset: 3px;
}

.site-header a:focus-visible,
.site-header button:focus-visible,
.site-footer a:focus-visible,
.site-footer button:focus-visible {
  outline: 3px solid var(--c-amber);
  outline-offset: 2px;
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0ms !important;
    scroll-behavior: auto !important;
  }

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

  .scroll-progress { transition: none; }
}