/* ==========================================================================
   英皇体育 · 红蓝电竞 CN
   /assets/site.css —— 全站共享：reset / 变量 / 中文排版 / 页头 / 页脚 / 基础组件
   ========================================================================== */

:root {
  --rb-cream: #F5EEE3;
  --rb-paper: #FFFCF6;
  --rb-ink: #1B1611;
  --rb-navy: #17305C;
  --rb-navy-deep: #0E1F3E;
  --rb-red: #DE3A2B;
  --rb-red-deep: #A8291D;
  --rb-cyan: #35DFCF;
  --rb-orange: #EE8A2B;
  --rb-graphite: #5A554C;
  --rb-steel: #C8D3E2;
  --rb-maroon: #47180F;

  --rb-line: rgba(27, 22, 17, 0.14);
  --rb-line-strong: rgba(27, 22, 17, 0.3);
  --rb-line-inv: rgba(255, 252, 246, 0.18);

  --rb-r-xs: 10px;
  --rb-r-sm: 16px;
  --rb-r-md: 24px;
  --rb-r-lg: 34px;
  --rb-r-pill: 999px;

  --rb-font-sans: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --rb-font-num: "Oswald", "Bebas Neue", "Arial Narrow", "Helvetica Neue", "Noto Sans SC", sans-serif;
  --rb-font-mono: ui-monospace, "JetBrains Mono", "Roboto Mono", "SFMono-Regular", Menlo, Consolas, monospace;

  --rb-shell: 1280px;
  --rb-gut: clamp(1.15rem, 4.6vw, 4.25rem);
  --rb-sp: clamp(2.5rem, 6vw, 6rem);
  --rb-header-h: 118px;
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 130px;
}

body {
  margin: 0;
  background-color: var(--rb-cream);
  background-image:
    linear-gradient(rgba(27, 22, 17, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(27, 22, 17, 0.045) 1px, transparent 1px);
  background-size: 64px 64px;
  color: var(--rb-ink);
  font-family: var(--rb-font-sans);
  font-size: clamp(1rem, 0.95rem + 0.18vw, 1.125rem);
  font-weight: 400;
  line-height: 1.75;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--rb-red) 0 50%, var(--rb-navy) 50% 100%);
  z-index: 100;
  pointer-events: none;
}

img, svg, video { max-width: 100%; height: auto; }
img { border: 0; }

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 0.5em;
  font-weight: 300;
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: inherit;
}

h1 { font-size: clamp(2.6rem, 7vw, 6.5rem); line-height: 1.02; letter-spacing: -0.02em; }
h2 { font-size: clamp(1.8rem, 3.4vw, 3.2rem); }
h3 { font-size: clamp(1.2rem, 1.9vw, 1.7rem); font-weight: 500; letter-spacing: 0; }
h4 { font-size: clamp(1rem, 1.3vw, 1.15rem); font-weight: 700; letter-spacing: 0.01em; }

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

ul, ol { margin: 0 0 1em; padding-left: 1.25em; }

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

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

::selection { background: var(--rb-red); color: var(--rb-paper); }

/* ---------- 焦点可见 ---------- */
:focus-visible {
  outline: 3px solid var(--rb-cyan);
  outline-offset: 2px;
  border-radius: 4px;
}

.rb-header[data-stuck] :focus-visible,
.rb-footer :focus-visible {
  outline-color: var(--rb-orange);
}

/* ---------- 容器与骨架 ---------- */
.rb-shell {
  width: min(100% - (var(--rb-gut) * 2), var(--rb-shell));
  margin-inline: auto;
}

.rb-main { display: block; }

.rb-section { padding-block: var(--rb-sp); }

.rb-section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 1rem 2rem;
  margin-bottom: clamp(1.5rem, 3vw, 2.75rem);
}

.rb-rule {
  border: 0;
  height: 1px;
  background: var(--rb-line-strong);
  margin-block: clamp(1.5rem, 4vw, 3rem);
}

.rb-note {
  border-left: 2px solid var(--rb-orange);
  padding-left: 1rem;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--rb-graphite);
}

/* ---------- 跳转链接 ---------- */
.rb-skip {
  position: fixed;
  top: 0;
  left: 50%;
  transform: translate(-50%, -160%);
  z-index: 130;
  padding: 0.6rem 1.2rem;
  background: var(--rb-ink);
  color: var(--rb-paper);
  border-radius: 0 0 var(--rb-r-pill) var(--rb-r-pill);
  font-size: 0.8125rem;
  letter-spacing: 0.1em;
  transition: transform 0.2s ease;
}

.rb-skip:focus,
.rb-skip:focus-visible {
  transform: translate(-50%, 0);
  outline-offset: 4px;
}

/* ==========================================================================
   页头
   ========================================================================== */
.rb-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background: transparent;
  color: var(--rb-ink);
  transition: background-color 0.28s ease, color 0.28s ease, box-shadow 0.28s ease;
}

.rb-header[data-stuck] {
  background: var(--rb-navy);
  color: var(--rb-paper);
  box-shadow: 0 1px 0 rgba(53, 223, 207, 0.4), 0 22px 44px -34px rgba(9, 18, 36, 0.95);
}

.rb-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: rgba(27, 22, 17, 0.08);
  overflow: hidden;
}

.rb-progress > span {
  display: block;
  width: 0;
  height: 100%;
  background: var(--rb-cyan);
  transition: width 0.1s linear;
}

/* 报头第一行：工具条 */
.rb-utility {
  border-bottom: 1px solid var(--rb-line);
  transition: border-color 0.28s ease;
}

.rb-header[data-stuck] .rb-utility { border-bottom-color: var(--rb-line-inv); }

.rb-utility__inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  min-height: 48px;
  padding-block: 0.3rem;
}

.rb-utility__motto {
  margin: 0;
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: var(--rb-graphite);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color 0.28s ease;
}

.rb-header[data-stuck] .rb-utility__motto { color: rgba(255, 252, 246, 0.72); }

.rb-utility__tools {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: clamp(0.5rem, 1.4vw, 1rem);
}

/* 赛段切换器 */
.rb-seg {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 3px;
  border-radius: var(--rb-r-pill);
  background: rgba(27, 22, 17, 0.07);
  transition: background-color 0.28s ease;
}

.rb-header[data-stuck] .rb-seg { background: rgba(255, 252, 246, 0.12); }

.rb-seg__btn {
  appearance: none;
  border: 0;
  cursor: pointer;
  padding: 0.28rem 0.78rem;
  border-radius: var(--rb-r-pill);
  background: transparent;
  color: var(--rb-graphite);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.rb-seg__btn:hover { color: var(--rb-ink); }

.rb-header[data-stuck] .rb-seg__btn { color: rgba(255, 252, 246, 0.72); }
.rb-header[data-stuck] .rb-seg__btn:hover { color: var(--rb-paper); }

.rb-seg__btn[aria-pressed="true"] {
  background: var(--rb-red);
  color: #FFF6F3;
}

.rb-header[data-stuck] .rb-seg__btn[aria-pressed="true"] {
  background: var(--rb-cyan);
  color: var(--rb-navy-deep);
}

/* 搜索入口 */
.rb-search {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.32rem 0.9rem 0.32rem 0.85rem;
  border: 1px solid var(--rb-line-strong);
  border-radius: var(--rb-r-pill);
  background: rgba(255, 252, 246, 0.6);
  color: var(--rb-graphite);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  transition: border-color 0.2s ease, color 0.2s ease, background-color 0.2s ease;
}

.rb-search:hover {
  border-color: var(--rb-red);
  color: var(--rb-ink);
}

.rb-search__icon { width: 14px; height: 14px; flex: none; }
.rb-search__label { white-space: nowrap; }

.rb-header[data-stuck] .rb-search {
  background: rgba(255, 252, 246, 0.08);
  border-color: rgba(255, 252, 246, 0.26);
  color: rgba(255, 252, 246, 0.8);
}

.rb-header[data-stuck] .rb-search:hover {
  border-color: var(--rb-cyan);
  color: var(--rb-paper);
}

/* 报头第二行 */
.rb-bar__inner {
  display: flex;
  align-items: center;
  gap: clamp(0.75rem, 2vw, 2.25rem);
  min-height: 64px;
  transition: min-height 0.28s ease;
}

.rb-header[data-stuck] .rb-bar__inner { min-height: 56px; }

.rb-brand { margin: 0; flex: 0 0 auto; }

.rb-brand__mark {
  display: inline-flex;
  align-items: baseline;
  gap: 0.55rem;
  padding-left: 0.7rem;
  border-left: 3px solid var(--rb-red);
}

.rb-header[data-stuck] .rb-brand__mark { border-left-color: var(--rb-cyan); }

.rb-brand__zh {
  font-size: 1.125rem;
  font-weight: 700;
  letter-spacing: 0.16em;
}

.rb-brand__en {
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.24em;
  color: var(--rb-red);
  transition: color 0.28s ease;
}

.rb-header[data-stuck] .rb-brand__en { color: var(--rb-cyan); }

/* 主导航 */
.rb-nav { display: block; }

.rb-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(0.35rem, 1.6vw, 1.5rem);
  margin: 0;
  padding: 0;
  list-style: none;
}

.rb-nav__link {
  position: relative;
  display: inline-block;
  padding: 0.45rem 0.15rem;
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  color: inherit;
  transition: color 0.2s ease;
}

.rb-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0.12rem;
  height: 2px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.22s ease;
}

.rb-nav__link:hover::after,
.rb-nav__link:focus-visible::after { transform: scaleX(1); }

.rb-nav__link[aria-current="page"] {
  color: var(--rb-red);
  font-weight: 700;
}

.rb-nav__link[aria-current="page"]::after { transform: scaleX(1); }

.rb-header[data-stuck] .rb-nav__link[aria-current="page"] { color: var(--rb-cyan); }

.rb-bar__actions {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

/* 移动导航开关 */
.rb-nav-toggle {
  display: none;
  align-items: center;
  gap: 0.55rem;
  appearance: none;
  cursor: pointer;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--rb-line-strong);
  border-radius: var(--rb-r-pill);
  background: transparent;
  color: inherit;
  font-size: 0.8125rem;
  letter-spacing: 0.12em;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.rb-nav-toggle:hover { border-color: var(--rb-red); color: var(--rb-red); }
.rb-header[data-stuck] .rb-nav-toggle { border-color: rgba(255, 252, 246, 0.3); }
.rb-header[data-stuck] .rb-nav-toggle:hover { border-color: var(--rb-cyan); color: var(--rb-cyan); }

.rb-nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: background-color 0.2s ease;
}

.rb-nav-toggle__bars::before,
.rb-nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform 0.22s ease;
}

.rb-nav-toggle__bars::before { top: -6px; }
.rb-nav-toggle__bars::after { top: 6px; }

.rb-header[data-open] .rb-nav-toggle__bars { background: transparent; }
.rb-header[data-open] .rb-nav-toggle__bars::before { transform: translateY(6px) rotate(45deg); }
.rb-header[data-open] .rb-nav-toggle__bars::after { transform: translateY(-6px) rotate(-45deg); }

/* ==========================================================================
   通用按钮 / 标签 / 数字 / 卡片
   ========================================================================== */
.rb-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.62rem 1.2rem;
  border: 1px solid transparent;
  border-radius: var(--rb-r-pill);
  cursor: pointer;
  font-family: var(--rb-font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  white-space: nowrap;
  text-align: center;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.18s ease, box-shadow 0.18s ease;
}

.rb-btn--red {
  background: var(--rb-red);
  color: #FFF6F3;
  box-shadow: 0 12px 26px -16px rgba(222, 58, 43, 0.95);
}

.rb-btn--red:hover { background: var(--rb-red-deep); transform: translateY(-2px); }

.rb-btn--navy { background: var(--rb-navy); color: var(--rb-paper); }
.rb-btn--navy:hover { background: var(--rb-navy-deep); transform: translateY(-2px); }

.rb-btn--ghost { background: transparent; border-color: var(--rb-line-strong); color: inherit; }
.rb-btn--ghost:hover { border-color: var(--rb-red); color: var(--rb-red); }
.rb-header[data-stuck] .rb-btn--ghost:hover { border-color: var(--rb-cyan); color: var(--rb-cyan); }

.rb-btn--cream {
  background: var(--rb-paper);
  color: var(--rb-ink);
  border-color: var(--rb-line-strong);
}

.rb-btn--cream:hover { border-color: var(--rb-navy); color: var(--rb-navy); transform: translateY(-2px); }

.rb-btn--sm { padding: 0.45rem 0.9rem; font-size: 0.8125rem; }

.rb-link {
  color: var(--rb-red);
  border-bottom: 1px solid rgba(222, 58, 43, 0.42);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.rb-link:hover { color: var(--rb-red-deep); border-bottom-color: currentColor; }

.rb-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.28rem 0.72rem;
  border: 1px solid var(--rb-line);
  border-radius: var(--rb-r-pill);
  background: var(--rb-paper);
  color: var(--rb-graphite);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  white-space: nowrap;
}

.rb-pill--red { background: rgba(222, 58, 43, 0.12); color: var(--rb-red-deep); border-color: rgba(222, 58, 43, 0.34); }
.rb-pill--blue { background: rgba(23, 48, 92, 0.1); color: var(--rb-navy); border-color: rgba(23, 48, 92, 0.32); }
.rb-pill--cyan { background: var(--rb-navy); color: var(--rb-cyan); border-color: transparent; }
.rb-pill--orange { background: rgba(238, 138, 43, 0.16); color: #8A4E0F; border-color: rgba(238, 138, 43, 0.42); }

.rb-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--rb-orange);
}

.rb-kicker::before {
  content: "";
  width: 22px;
  height: 2px;
  background: currentColor;
}

.rb-index {
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--rb-graphite);
}

.rb-num {
  display: inline-block;
  font-family: var(--rb-font-num);
  font-weight: 700;
  font-stretch: condensed;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  line-height: 0.84;
}

.rb-num--xl { font-size: clamp(3.2rem, 9vw, 8rem); }
.rb-num--hero { font-size: clamp(4.5rem, 14vw, 14rem); }
.rb-num--red { color: var(--rb-red); }
.rb-num--blue { color: var(--rb-navy); }
.rb-num--cyan { color: var(--rb-cyan); }

.rb-display {
  font-weight: 300;
  font-size: clamp(2.8rem, 7.5vw, 7rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
}

.rb-lede {
  max-width: 34em;
  font-size: clamp(1.0625rem, 1rem + 0.5vw, 1.3125rem);
  line-height: 1.7;
  color: var(--rb-graphite);
}

.rb-card {
  position: relative;
  padding: clamp(1.25rem, 2.6vw, 2rem);
  background: var(--rb-paper);
  border: 1px solid var(--rb-line);
  border-radius: var(--rb-r-lg);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.rb-card:hover {
  transform: translateY(-3px);
  border-color: var(--rb-cyan);
  box-shadow: 0 28px 52px -34px rgba(27, 22, 17, 0.6);
}

.rb-card--ink { background: var(--rb-ink); color: var(--rb-paper); border-color: transparent; }
.rb-card--ink .rb-lede, .rb-card--ink .rb-index { color: rgba(255, 252, 246, 0.74); }
.rb-card--navy { background: var(--rb-navy); color: var(--rb-paper); border-color: transparent; }
.rb-card--navy .rb-lede, .rb-card--navy .rb-index { color: rgba(255, 252, 246, 0.76); }
.rb-card--maroon { background: var(--rb-maroon); color: var(--rb-paper); border-color: transparent; }
.rb-card--maroon .rb-lede, .rb-card--maroon .rb-index { color: rgba(255, 252, 246, 0.76); }
.rb-card--flat:hover { transform: none; box-shadow: none; border-color: var(--rb-line); }

/* ---------- 网格 ---------- */
.rb-bento {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(0.85rem, 1.6vw, 1.4rem);
}

.rb-bento > * { grid-column: span 12; }

@media (min-width: 720px) {
  .rb-bento > .rb-span-3 { grid-column: span 3; }
  .rb-bento > .rb-span-4 { grid-column: span 4; }
  .rb-bento > .rb-span-5 { grid-column: span 5; }
  .rb-bento > .rb-span-6 { grid-column: span 6; }
  .rb-bento > .rb-span-7 { grid-column: span 7; }
  .rb-bento > .rb-span-8 { grid-column: span 8; }
  .rb-bento > .rb-span-9 { grid-column: span 9; }
  .rb-bento > .rb-row-2 { grid-row: span 2; }
}

.rb-grid {
  display: grid;
  gap: clamp(1rem, 2.4vw, 2rem);
}

.rb-grid--2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.rb-grid--3 { grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); }

/* ---------- 面包屑 ---------- */
.rb-crumbs { padding-top: clamp(0.75rem, 2vw, 1.25rem); }

.rb-crumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  color: var(--rb-graphite);
}

.rb-crumbs__list li { display: inline-flex; align-items: center; }
.rb-crumbs__list li + li::before { content: "/"; margin: 0 0.6rem; color: var(--rb-orange); }
.rb-crumbs__list a { transition: color 0.2s ease; }
.rb-crumbs__list a:hover { color: var(--rb-red); }

/* ---------- 表格 ---------- */
.rb-table-wrap {
  overflow-x: auto;
  background: var(--rb-paper);
  border: 1px solid var(--rb-line);
  border-radius: var(--rb-r-md);
  -webkit-overflow-scrolling: touch;
}

.rb-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--rb-font-mono);
  font-size: 0.8125rem;
  font-variant-numeric: tabular-nums;
}

.rb-table caption {
  padding: 0.9rem 1rem 0.2rem;
  text-align: left;
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: var(--rb-graphite);
}

.rb-table th,
.rb-table td {
  padding: 0.7rem 0.9rem;
  text-align: left;
  border-bottom: 1px solid var(--rb-line);
  white-space: nowrap;
}

.rb-table thead th {
  background: rgba(200, 211, 226, 0.3);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--rb-graphite);
}

.rb-table tbody tr { transition: background-color 0.16s ease; }
.rb-table tbody tr:nth-child(even) { background: rgba(200, 211, 226, 0.18); }
.rb-table tbody tr:hover { background: rgba(53, 223, 207, 0.16); }
.rb-table tbody td:first-child { border-left: 3px solid transparent; }
.rb-table tbody tr:hover td:first-child { border-left-color: var(--rb-cyan); }

/* ---------- 图片容器 ---------- */
.rb-figure {
  position: relative;
  display: block;
  margin: 0;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border-radius: var(--rb-r-lg);
  background: var(--rb-steel);
  isolation: isolate;
}

.rb-figure > img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.rb-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255, 252, 246, 0.16) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 252, 246, 0.16) 1px, transparent 1px);
  background-size: 32px 32px;
  mix-blend-mode: overlay;
}

.rb-figure--wide { aspect-ratio: 16 / 9; }
.rb-figure--tall { aspect-ratio: 4 / 5; }
.rb-figure--square { aspect-ratio: 1 / 1; }
.rb-figure--soft { border-radius: var(--rb-r-md); }
.rb-figure--red { box-shadow: inset 0 0 0 2px rgba(222, 58, 43, 0.62); }
.rb-figure--blue { box-shadow: inset 0 0 0 2px rgba(23, 48, 92, 0.62); }

.rb-figure__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 1.6rem 1.1rem 0.9rem;
  background: linear-gradient(transparent, rgba(20, 16, 12, 0.8));
  color: var(--rb-paper);
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
}

/* ==========================================================================
   页脚
   ========================================================================== */
.rb-footer {
  position: relative;
  margin-top: clamp(3rem, 8vw, 7rem);
  padding-block: clamp(2.5rem, 6vw, 4.5rem) 0;
  background: var(--rb-navy);
  color: rgba(255, 252, 246, 0.84);
  overflow: hidden;
}

.rb-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255, 252, 246, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 252, 246, 0.06) 1px, transparent 1px);
  background-size: 56px 56px;
}

.rb-footer > .rb-shell { position: relative; z-index: 1; }

.rb-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) repeat(3, minmax(0, 0.62fr));
  gap: clamp(1.5rem, 4vw, 3.5rem);
}

.rb-footer__name {
  margin: 0;
  padding-left: 0.7rem;
  border-left: 3px solid var(--rb-red);
  color: var(--rb-paper);
  font-size: 1.375rem;
  font-weight: 700;
  letter-spacing: 0.16em;
}

.rb-footer__tag {
  margin: 0.5rem 0 0;
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.24em;
  color: var(--rb-cyan);
}

.rb-footer__summary {
  margin: 0.9rem 0 0;
  max-width: 34em;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(255, 252, 246, 0.72);
}

.rb-footer__title {
  margin: 0;
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--rb-orange);
}

.rb-footer__list {
  display: grid;
  gap: 0.55rem;
  margin: 0.95rem 0 0;
  padding: 0;
  list-style: none;
}

.rb-footer__list a {
  display: inline-block;
  padding-bottom: 2px;
  font-size: 0.9375rem;
  color: rgba(255, 252, 246, 0.88);
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.rb-footer__list a:hover,
.rb-footer__list a:focus-visible {
  color: var(--rb-cyan);
  border-bottom-color: var(--rb-cyan);
}

.rb-footer__contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1.1rem 2rem;
  margin-top: clamp(2rem, 5vw, 3.25rem);
  padding-top: clamp(1.5rem, 3vw, 2rem);
  border-top: 1px solid var(--rb-line-inv);
}

.rb-contact__k {
  display: block;
  margin-bottom: 0.3rem;
  font-family: var(--rb-font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.22em;
  color: var(--rb-orange);
}

.rb-contact__v {
  display: block;
  font-family: var(--rb-font-mono);
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--rb-paper);
  word-break: break-word;
}

.rb-footer__note {
  grid-column: 1 / -1;
  margin: 0;
  font-size: 0.8125rem;
  line-height: 1.75;
  color: rgba(255, 252, 246, 0.62);
}

.rb-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.7rem 1.75rem;
  margin-top: clamp(1.5rem, 3vw, 2.5rem);
  padding-block: 1.25rem 1.75rem;
  border-top: 1px solid var(--rb-line-inv);
  font-size: 0.8125rem;
  color: rgba(255, 252, 246, 0.64);
}

.rb-footer__copy { margin: 0; }

.rb-footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.4rem;
}

.rb-footer__legal a { transition: color 0.2s ease; }
.rb-footer__legal a:hover { color: var(--rb-cyan); }

.rb-footer__icp {
  margin: 0;
  font-family: var(--rb-font-mono);
  letter-spacing: 0.08em;
}

/* 返回顶部 */
.rb-to-top {
  position: fixed;
  right: clamp(0.9rem, 3vw, 1.6rem);
  bottom: clamp(0.9rem, 3vw, 1.6rem);
  z-index: 85;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  padding: 0;
  border: 1px solid var(--rb-line-strong);
  border-radius: 50%;
  background: var(--rb-paper);
  color: var(--rb-ink);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  box-shadow: 0 16px 30px -22px rgba(27, 22, 17, 0.9);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.rb-to-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.rb-to-top:hover { border-color: var(--rb-cyan); color: var(--rb-red); }

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 1080px) {
  .rb-footer__top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .rb-footer__brand { grid-column: 1 / -1; }
}

@media (max-width: 960px) {
  .rb-nav-toggle { display: inline-flex; }

  .rb-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
    padding: 0.75rem var(--rb-gut) 1.5rem;
    background: var(--rb-navy);
    color: var(--rb-paper);
    box-shadow: 0 34px 60px -34px rgba(9, 18, 36, 0.95);
  }

  .rb-header[data-open] .rb-nav { display: block; }
  .rb-header[data-stuck] .rb-nav { background: var(--rb-navy-deep); }

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

  .rb-nav__link {
    display: block;
    padding: 0.85rem 0.2rem;
    font-size: 1.0625rem;
    border-bottom: 1px solid var(--rb-line-inv);
  }

  .rb-nav__link::after { display: none; }
  .rb-nav__link[aria-current="page"] { color: var(--rb-cyan); }

  .rb-utility .rb-seg { display: none; }
  .rb-search__label { display: none; }
  .rb-search { padding: 0.4rem; }

  .rb-header[data-stuck] { position: sticky; }
}

@media (max-width: 640px) {
  :root { --rb-header-h: 104px; scroll-padding-top: 110px; }

  .rb-utility__motto { display: none; }
  .rb-brand__en { display: none; }
  .rb-brand__zh { font-size: 1rem; letter-spacing: 0.1em; }
  .rb-bar__cta { padding: 0.5rem 0.85rem; font-size: 0.8125rem; }
  .rb-nav-toggle { padding: 0.44rem 0.72rem; }
  .rb-nav-toggle__text { display: none; }

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

@media print {
  .rb-header, .rb-footer, .rb-to-top, .rb-progress { display: none; }
  body { background: #fff; }
}

/* ==========================================================================
   动效降级
   ========================================================================== */
@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;
    scroll-behavior: auto !important;
  }

  .rb-card:hover { transform: none; }
  .rb-btn:hover { transform: none; }
}