/* =========================================================
   买球官网 · 共享样式 /assets/site.css
   夜间路径控制台：蓝图网格 + 左侧路径轴 + 底部状态栏
   ========================================================= */

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, h6, p, ol, ul, li, figure, blockquote, dl, dd, details, summary { margin: 0; }
ol, ul { list-style: none; padding: 0; }
img, picture, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
summary { list-style: none; }
summary::-webkit-details-marker { display: none; }

/* ---------- tokens ---------- */
:root {
  --ink-void: #050A18;
  --ink-panel: #0C1428;
  --ink-float: #16213C;
  --line-grid: #2A3654;
  --cyan: #5BE7D6;
  --orange: #FF7A3D;
  --violet: #7A6BFF;
  --muted: #A9B6CE;
  --bright: #E8EEF9;

  --rail-w: 272px;
  --status-h: 52px;
  --radius: 14px;
  --bevel: 18px;

  --font-display: "PingFang SC", "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-body: system-ui, -apple-system, "PingFang SC", "HarmonyOS Sans SC", "Noto Sans SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", "Courier New", monospace;

  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- base ---------- */
body {
  min-height: 100vh;
  background-color: var(--ink-void);
  background-image:
    radial-gradient(900px 620px at 78% -12%, rgba(122, 107, 255, .17), transparent 62%),
    radial-gradient(680px 520px at 10% 6%, rgba(91, 231, 214, .10), transparent 64%),
    linear-gradient(to right, rgba(42, 54, 84, .40) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(42, 54, 84, .40) 1px, transparent 1px);
  background-size: auto, auto, 88px 88px, 88px 88px;
  background-attachment: fixed, fixed, fixed, fixed;
  color: var(--bright);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  padding-bottom: var(--status-h);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
#main-content { display: block; outline: none; }

h1, h2, h3, h4 { font-family: var(--font-display); line-height: 1.25; letter-spacing: .01em; }
h1 { font-weight: 700; font-size: clamp(2.2rem, 6vw, 4.6rem); letter-spacing: .02em; }
h2 { font-weight: 700; font-size: clamp(1.25rem, 2.4vw, 1.75rem); }
h3 { font-weight: 600; font-size: clamp(1.05rem, 1.6vw, 1.25rem); }
strong, b { color: var(--bright); font-weight: 600; }
code, kbd, samp { font-family: var(--font-mono); font-size: .88em; color: var(--cyan); }

::selection { background: rgba(91, 231, 214, .28); color: var(--bright); }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 4px;
}

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

.skip-link {
  position: fixed; top: 10px; left: 10px; z-index: 200;
  transform: translateY(-200%);
  background: var(--cyan); color: #04211D;
  padding: 10px 18px; border-radius: 8px;
  font-weight: 700; letter-spacing: .06em; font-size: .9rem;
  transition: transform .18s var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- layout helpers ---------- */
.container { width: 100%; max-width: 1180px; margin-inline: auto; padding-inline: clamp(20px, 4vw, 44px); }
.section { padding-block: clamp(52px, 9vw, 118px); }
.section--tight { padding-block: clamp(32px, 5vw, 64px); }

.lede {
  max-width: 40rem;
  font-size: clamp(1.02rem, 1.6vw, 1.22rem);
  line-height: 1.85;
  color: var(--bright);
}
.prose { max-width: 40rem; color: var(--muted); font-size: 1rem; line-height: 1.85; }
.prose > * + * { margin-top: 1.05em; }
.prose a { color: var(--cyan); border-bottom: 1px solid rgba(91, 231, 214, .4); }
.prose a:hover { border-bottom-color: var(--cyan); }

.note {
  font-size: .85rem; line-height: 1.75; color: var(--muted);
  padding-left: 12px; border-left: 2px solid var(--line-grid);
}
.note--cyan { border-left-color: var(--cyan); }

.notice {
  display: flex; gap: 12px; align-items: flex-start;
  padding: 16px 18px;
  border: 1px dashed rgba(91, 231, 214, .45);
  border-radius: 12px;
  background: rgba(91, 231, 214, .05);
  color: var(--muted); font-size: .93rem; line-height: 1.8;
}

.panel {
  background: var(--ink-panel);
  border: 1px solid var(--line-grid);
  border-radius: var(--radius);
  padding: clamp(20px, 3vw, 34px);
}

/* ---------- 编号章节 ---------- */
.chapter {
  position: relative;
  padding-block: clamp(54px, 8vw, 108px);
  border-top: 1px solid rgba(42, 54, 84, .8);
}
.chapter:first-of-type { border-top: 0; }
.chapter__head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 14px; margin-bottom: 26px; }
.chapter__num {
  font-family: var(--font-mono);
  font-size: .82rem; letter-spacing: .24em;
  color: var(--cyan);
  transition: color .22s var(--ease);
}
.chapter__title { font-size: clamp(1.25rem, 2.4vw, 1.75rem); font-weight: 700; }
.chapter__rule {
  flex: 1 1 80px; min-width: 48px; height: 1px;
  background: linear-gradient(90deg, rgba(91, 231, 214, .95), rgba(91, 231, 214, 0));
  position: relative;
  transition: background .22s var(--ease);
}
.chapter__rule::after {
  content: ""; position: absolute; right: 0; top: -2.5px;
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--orange);
}
.chapter__sub { flex: 1 0 100%; color: var(--muted); font-size: .88rem; letter-spacing: .04em; }
.chapter.is-current .chapter__num { color: var(--orange); }
.chapter.is-current .chapter__rule { background: linear-gradient(90deg, rgba(255, 122, 61, .95), rgba(255, 122, 61, 0)); }

/* ---------- 网格 ---------- */
.grid { display: grid; gap: clamp(16px, 2.4vw, 26px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--asym { grid-template-columns: minmax(0, 7fr) minmax(0, 3fr); }

/* ---------- 卡片 ---------- */
.card {
  position: relative;
  background: linear-gradient(160deg, rgba(22, 33, 60, .96), rgba(12, 20, 40, .96));
  border: 1px solid var(--line-grid);
  border-radius: var(--radius);
  padding: clamp(20px, 3vw, 30px);
}
.card--float { box-shadow: 0 34px 60px -44px rgba(0, 0, 0, .95); }
.card--bevel {
  border-radius: 0;
  clip-path: polygon(0 0, calc(100% - var(--bevel)) 0, 100% var(--bevel), 100% 100%, var(--bevel) 100%, 0 calc(100% - var(--bevel)));
}
.card__meta {
  display: block;
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .18em;
  color: var(--cyan); text-transform: uppercase; margin-bottom: 12px;
}
.card__title { font-size: clamp(1.05rem, 1.7vw, 1.25rem); font-weight: 600; margin-bottom: 10px; }
.card__body { color: var(--muted); font-size: .95rem; line-height: 1.85; }

/* ---------- 按钮 ---------- */
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; }
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 13px 22px;
  border: 1px solid var(--line-grid);
  border-radius: 999px;
  background: var(--ink-float);
  color: var(--bright);
  font-size: .92rem; font-weight: 600; letter-spacing: .04em;
  transition: color .18s var(--ease), border-color .18s var(--ease), background .18s var(--ease), transform .18s var(--ease);
}
.btn:hover { border-color: var(--cyan); color: var(--cyan); }
.btn--primary {
  background: linear-gradient(120deg, var(--orange), #FFA268);
  border-color: transparent; color: #1A0700;
}
.btn--primary:hover { color: #1A0700; transform: translateY(-1px); box-shadow: 0 16px 32px -18px rgba(255, 122, 61, .95); }
.btn--ghost { background: transparent; border-color: rgba(91, 231, 214, .5); color: var(--cyan); }
.btn--ghost:hover { background: rgba(91, 231, 214, .09); }

/* ---------- 标签 / 数据 / 状态点 ---------- */
.tag {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 5px 11px; border-radius: 999px;
  border: 1px solid var(--line-grid);
  background: rgba(22, 33, 60, .65);
  color: var(--muted);
  font-family: var(--font-mono); font-size: .69rem; letter-spacing: .14em;
}
.tag--cyan { color: var(--cyan); border-color: rgba(91, 231, 214, .45); background: rgba(91, 231, 214, .08); }
.tag--orange { color: var(--orange); border-color: rgba(255, 122, 61, .45); background: rgba(255, 122, 61, .08); }
.tag--violet { color: var(--violet); border-color: rgba(122, 107, 255, .5); background: rgba(122, 107, 255, .11); }

.stat-row { display: flex; flex-wrap: wrap; gap: clamp(18px, 3vw, 42px); }
.stat { min-width: 118px; }
.stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.35rem, 2.8vw, 2rem);
  letter-spacing: .02em; color: var(--bright);
}
.stat__label { display: block; margin-top: 4px; font-size: .76rem; letter-spacing: .1em; color: var(--muted); }

.dot {
  flex: 0 0 auto; width: 7px; height: 7px; margin-top: .55em;
  border-radius: 50%; background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(91, 231, 214, .14);
}

/* ---------- 面包屑 ---------- */
.breadcrumb { padding-block: 20px; font-family: var(--font-mono); font-size: .72rem; letter-spacing: .12em; color: var(--muted); }
.breadcrumb__list { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; }
.breadcrumb__item { display: flex; align-items: center; gap: 10px; color: var(--muted); }
.breadcrumb__item + .breadcrumb__item::before { content: "›"; color: var(--line-grid); font-size: .95rem; }
.breadcrumb__item a:hover { color: var(--cyan); }
.breadcrumb__item[aria-current="page"] { color: var(--bright); }

/* ---------- 版本 / 设备对照 ---------- */
.compare {
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px; background: var(--line-grid);
  border: 1px solid var(--line-grid); border-radius: var(--radius); overflow: hidden;
}
.compare__col { background: var(--ink-panel); padding: clamp(18px, 2.6vw, 28px); }
.compare__head {
  display: block; margin-bottom: 16px; padding-bottom: 12px;
  border-bottom: 1px dashed var(--line-grid);
  font-family: var(--font-mono); font-size: .73rem; letter-spacing: .18em; color: var(--cyan);
}
.compare__col--alt .compare__head { color: var(--violet); }
.compare__row {
  display: flex; justify-content: space-between; align-items: baseline; gap: 14px;
  padding: 10px 0; border-bottom: 1px solid rgba(42, 54, 84, .6);
  font-size: .92rem; color: var(--muted);
}
.compare__row:last-child { border-bottom: 0; }
.compare__key { color: var(--bright); }
.compare__val { font-family: var(--font-mono); font-size: .82rem; letter-spacing: .06em; text-align: right; }

/* ---------- 本地切换 ---------- */
.switch {
  display: inline-flex; gap: 4px; padding: 4px;
  border: 1px solid var(--line-grid); border-radius: 999px;
  background: rgba(12, 20, 40, .92);
}
.switch__btn {
  padding: 8px 16px; border-radius: 999px;
  font-size: .84rem; letter-spacing: .04em; color: var(--muted);
  transition: background .18s var(--ease), color .18s var(--ease);
}
.switch__btn:hover { color: var(--bright); }
.switch__btn[aria-selected="true"] {
  background: linear-gradient(120deg, rgba(255, 122, 61, .95), rgba(255, 166, 104, .85));
  color: #1A0700; font-weight: 600;
}
[data-switch-panel] { animation: panelIn .18s var(--ease) both; }
[data-switch-panel][hidden] { display: none; }
@keyframes panelIn { from { opacity: 0; transform: translateX(8px); } to { opacity: 1; transform: none; } }

/* ---------- 折叠栏目 ---------- */
.fold {
  border: 1px solid var(--line-grid); border-radius: var(--radius);
  background: rgba(12, 20, 40, .82); overflow: hidden;
}
.fold + .fold { margin-top: 12px; }
.fold__summary {
  display: flex; align-items: center; gap: 14px;
  padding: 18px 20px; cursor: pointer;
  font-weight: 600; color: var(--bright);
  transition: color .18s var(--ease);
}
.fold__summary:hover { color: var(--cyan); }
.fold__idx { font-family: var(--font-mono); font-size: .72rem; letter-spacing: .18em; color: var(--cyan); }
.fold__summary::after {
  content: ""; margin-left: auto; flex: 0 0 auto;
  width: 9px; height: 9px;
  border-right: 2px solid var(--cyan); border-bottom: 2px solid var(--cyan);
  transform: rotate(45deg);
  transition: transform .2s var(--ease);
}
.fold[open] .fold__summary::after { transform: rotate(-135deg); }
.fold__body { padding: 0 20px 20px; color: var(--muted); font-size: .94rem; line-height: 1.85; }

/* ---------- 图片容器（页面阶段放置图片） ---------- */
.media {
  position: relative; overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line-grid);
  border-radius: var(--radius);
  background: linear-gradient(150deg, #0C1428, #101A33);
}
.media::before {
  content: ""; position: absolute; left: -12%; top: -25%;
  width: 58%; height: 150%;
  background: linear-gradient(90deg, rgba(91, 231, 214, .16), transparent 72%);
  transform: rotate(-18deg);
  pointer-events: none;
}
.media::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(42, 54, 84, .45) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(42, 54, 84, .45) 1px, transparent 1px);
  background-size: 34px 34px;
  opacity: .6;
}
.media > img, .media > picture > img {
  width: 100%; height: 100%; object-fit: cover;
  filter: saturate(.82) contrast(1.04) brightness(.92);
}
.media--wide { aspect-ratio: 21 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media__cap {
  position: absolute; left: 14px; bottom: 12px; z-index: 2;
  padding: 4px 9px; border-radius: 6px;
  background: rgba(5, 10, 24, .76);
  font-family: var(--font-mono); font-size: .69rem; letter-spacing: .12em; color: var(--muted);
}

/* ---------- 显现 ---------- */
.reveal-ready [data-reveal] { opacity: 0; transform: translateY(14px); }
.reveal-ready [data-reveal].is-visible {
  opacity: 1; transform: none;
  transition: opacity .48s var(--ease), transform .48s var(--ease);
}

/* =========================================================
   顶部：阅读进度 + 左侧路径轴
   ========================================================= */
.read-progress {
  position: fixed; top: 0; left: 0; right: 0; height: 3px;
  z-index: 90; pointer-events: none; background: rgba(42, 54, 84, .5);
}
.read-progress__bar {
  display: block; height: 100%; width: 0;
  background: linear-gradient(90deg, var(--cyan), var(--violet) 58%, var(--orange));
}

.site-header {
  position: fixed; top: 0; bottom: 0; left: 0;
  width: var(--rail-w); z-index: 50;
  background: linear-gradient(180deg, #0C1428 0%, #070D1E 55%, #050A18 100%);
  border-right: 1px solid var(--line-grid);
}
.site-header::after {
  content: ""; position: absolute; top: 0; right: -1px;
  width: 1px; height: 34%;
  background: linear-gradient(180deg, var(--cyan), rgba(91, 231, 214, 0));
}

.rail {
  display: flex; flex-direction: column; gap: 22px;
  height: 100%; padding: 26px 22px 22px;
  overflow-y: auto; overscroll-behavior: contain;
}
.rail__top { display: flex; flex-direction: column; gap: 14px; }

.brand { display: flex; align-items: center; gap: 12px; }
.brand__mark {
  position: relative; flex: 0 0 auto;
  width: 36px; height: 36px;
  border: 1px solid var(--cyan); border-radius: 50%;
}
.brand__mark::before {
  content: ""; position: absolute; inset: 6px;
  border: 1px dashed rgba(91, 231, 214, .5); border-radius: 50%;
}
.brand__mark::after {
  content: ""; position: absolute; left: 50%; top: 50%;
  width: 24px; height: 1px; background: var(--orange);
  transform: translate(-50%, -50%) rotate(-38deg);
}
.brand__text { display: flex; flex-direction: column; min-width: 0; }
.brand__name { font-family: var(--font-display); font-weight: 700; font-size: 1.06rem; letter-spacing: .1em; color: var(--bright); }
.brand__line { margin-top: 3px; font-size: .7rem; line-height: 1.5; letter-spacing: .04em; color: var(--muted); }

.nav-toggle {
  display: none; align-items: center; gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line-grid); border-radius: 999px;
  color: var(--bright); font-size: .8rem; letter-spacing: .08em;
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }
.nav-toggle__icon { display: inline-flex; flex-direction: column; gap: 3px; width: 16px; }
.nav-toggle__icon span { display: block; height: 1px; background: var(--cyan); transition: width .2s var(--ease); }
.nav-toggle__icon span:nth-child(2) { width: 68%; }
.nav-toggle__text { font-family: var(--font-mono); }

.rail__sub {
  font-size: .77rem; line-height: 1.7; color: var(--muted);
  padding-left: 12px; border-left: 2px solid rgba(255, 122, 61, .85);
}

.site-nav { min-width: 0; }
.nav-hint {
  margin-bottom: 12px;
  font-family: var(--font-mono); font-size: .66rem; line-height: 1.7;
  letter-spacing: .08em; color: var(--muted); opacity: .75;
}
.nav-list { position: relative; display: flex; flex-direction: column; gap: 2px; }
.nav-list::before {
  content: ""; position: absolute; left: 9px; top: 10px; bottom: 10px; width: 1px;
  background: linear-gradient(180deg, rgba(91, 231, 214, .6), rgba(42, 54, 84, .9) 42%, rgba(42, 54, 84, .3));
}
.nav-item { position: relative; }
.nav-link {
  position: relative; display: flex; align-items: baseline; gap: 10px;
  padding: 10px 10px 10px 30px;
  border-radius: 10px;
  color: var(--muted); font-size: .94rem;
  transition: color .18s var(--ease), background .18s var(--ease);
}
.nav-link::before {
  content: ""; position: absolute; left: 5px; top: 50%;
  width: 9px; height: 9px; margin-top: -4.5px;
  border-radius: 50%;
  background: var(--ink-void); border: 1px solid var(--line-grid);
  transition: background .18s var(--ease), border-color .18s var(--ease), box-shadow .18s var(--ease);
}
.nav-link:hover { color: var(--bright); background: rgba(22, 33, 60, .7); }
.nav-link:hover::before { border-color: var(--cyan); }
.nav-link[aria-current="page"] {
  color: var(--bright);
  background: linear-gradient(90deg, rgba(122, 107, 255, .26), rgba(22, 33, 60, .18));
}
.nav-link[aria-current="page"]::before {
  background: var(--cyan); border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(91, 231, 214, .15);
}
.nav-link__idx { font-family: var(--font-mono); font-size: .7rem; letter-spacing: .16em; color: var(--cyan); }
.nav-link[aria-current="page"] .nav-link__idx { color: var(--orange); }
.nav-link__label { letter-spacing: .03em; }

.rail__foot {
  margin-top: auto;
  display: flex; flex-direction: column; gap: 10px;
  padding-top: 18px; border-top: 1px dashed var(--line-grid);
}
.rail__status { display: flex; align-items: flex-start; gap: 9px; font-size: .74rem; line-height: 1.6; color: var(--muted); }
.rail__cta {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 11px 16px; border-radius: 999px;
  background: var(--orange); color: #1A0700;
  font-size: .86rem; font-weight: 700; letter-spacing: .05em;
  transition: transform .2s var(--ease), box-shadow .2s var(--ease);
}
.rail__cta:hover { transform: translateX(2px); box-shadow: 0 12px 26px -14px rgba(255, 122, 61, .95); }
.rail__link {
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .1em;
  color: var(--muted); border-bottom: 1px solid transparent; align-self: flex-start;
}
.rail__link:hover { color: var(--cyan); border-bottom-color: rgba(91, 231, 214, .5); }

/* =========================================================
   页脚 + 底部状态栏
   ========================================================= */
.site-footer {
  position: relative;
  margin-top: clamp(40px, 6vw, 84px);
  padding-top: clamp(48px, 7vw, 86px);
  border-top: 1px solid var(--line-grid);
  background: linear-gradient(180deg, rgba(5, 10, 24, .2), #080E1F 46%, #0C1428 100%);
}
.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) repeat(3, minmax(0, 1fr));
  gap: clamp(24px, 3vw, 42px);
}
.footer-brand__name { font-family: var(--font-display); font-weight: 700; font-size: 1.22rem; letter-spacing: .12em; color: var(--bright); }
.footer-brand__line { margin-top: 7px; font-family: var(--font-mono); font-size: .72rem; letter-spacing: .16em; color: var(--cyan); }
.footer-brand__note { margin-top: 15px; max-width: 30rem; font-size: .88rem; line-height: 1.85; color: var(--muted); }

.footer-col__title {
  padding-bottom: 10px; margin-bottom: 14px;
  border-bottom: 1px solid var(--line-grid);
  font-family: var(--font-mono); font-size: .71rem; font-weight: 600;
  letter-spacing: .2em; color: var(--bright);
}
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links a {
  display: inline-block;
  font-size: .92rem; color: var(--muted);
  transition: color .18s var(--ease), transform .18s var(--ease);
}
.footer-links a:hover { color: var(--cyan); transform: translateX(3px); }

.footer-contact {
  margin-top: clamp(32px, 5vw, 58px);
  padding-top: 24px;
  border-top: 1px dashed var(--line-grid);
  display: flex; flex-direction: column; gap: 8px;
  font-size: .87rem; line-height: 1.8; color: var(--muted);
}
.footer-contact__key {
  display: inline-block; min-width: 6.4em;
  font-family: var(--font-mono); font-size: .72rem; letter-spacing: .12em;
  color: var(--cyan);
}
.footer-response { margin-top: 6px; font-size: .83rem; color: var(--muted); }

.footer-meta {
  margin-top: 26px;
  padding-block: 22px;
  border-top: 1px solid var(--line-grid);
  display: flex; flex-wrap: wrap; gap: 10px 24px;
  align-items: center; justify-content: space-between;
  font-family: var(--font-mono); font-size: .71rem; letter-spacing: .08em; color: var(--muted);
}
.footer-legal, .footer-copy { line-height: 1.8; }

.status-bar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 70;
  height: var(--status-h);
  display: flex; align-items: center; gap: 18px;
  padding: 0 18px;
  background: rgba(5, 10, 24, .94);
  border-top: 1px solid var(--line-grid);
  backdrop-filter: blur(10px);
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .1em; color: var(--muted);
}
.status-bar__item { display: inline-flex; align-items: center; gap: 8px; white-space: nowrap; }
.status-bar__key { color: #5C6B8A; }
.status-bar__val { color: var(--bright); letter-spacing: .06em; }
.status-bar__cta {
  margin-left: auto;
  padding: 6px 13px; border-radius: 999px;
  border: 1px solid rgba(255, 122, 61, .48);
  color: var(--orange); letter-spacing: .08em;
  transition: background .18s var(--ease), color .18s var(--ease);
}
.status-bar__cta:hover { background: rgba(255, 122, 61, .15); color: #FFB28C; }

/* =========================================================
   响应式
   ========================================================= */
@media (min-width: 1025px) {
  body { padding-left: var(--rail-w); }
  .read-progress { left: var(--rail-w); }
  .status-bar { left: var(--rail-w); }
}
@media (min-width: 1025px) and (max-width: 1300px) {
  :root { --rail-w: 236px; }
}

@media (max-width: 1024px) {
  .site-header {
    position: sticky; inset: auto; top: 0;
    width: auto;
    border-right: 0; border-bottom: 1px solid var(--line-grid);
    background: linear-gradient(180deg, rgba(12, 20, 40, .98), rgba(5, 10, 24, .96));
    backdrop-filter: blur(10px);
  }
  .site-header::after { display: none; }
  .rail { height: auto; gap: 14px; padding: 14px 18px 16px; overflow: visible; }
  .rail__top { flex-direction: row; align-items: center; justify-content: space-between; gap: 14px; }
  .nav-toggle { display: inline-flex; }
  .site-nav { display: none; }
  .site-header[data-open] .site-nav { display: block; animation: navDrop .18s var(--ease) both; }
  .site-header[data-open] .nav-toggle__icon span:nth-child(2) { width: 100%; }
  .nav-list { flex-direction: column; }
  .nav-link { padding: 12px 12px 12px 30px; font-size: .96rem; }
  .rail__foot {
    margin-top: 0;
    flex-direction: row; flex-wrap: wrap; align-items: center; justify-content: space-between;
    gap: 10px 16px;
  }
  .rail__status { flex: 1 1 100%; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@keyframes navDrop { from { opacity: 0; transform: translateY(-6px); } to { opacity: 1; transform: none; } }

@media (max-width: 900px) {
  .grid--2, .grid--3, .grid--asym { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 760px) {
  .compare { grid-template-columns: minmax(0, 1fr); }
  .chapter__rule { flex-basis: 40px; }
}

@media (max-width: 640px) {
  :root { --status-h: 46px; }
  body { background-size: auto, auto, 64px 64px, 64px 64px; }
  .brand__mark { width: 32px; height: 32px; }
  .brand__line { font-size: .66rem; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .status-bar { gap: 12px; padding: 0 12px; font-size: .63rem; }
  .status-bar__item--wide { display: none; }
  .footer-contact__key { min-width: 5.6em; }
}

@media (max-width: 420px) {
  .nav-toggle__text { display: none; }
  .footer-meta { font-size: .66rem; }
}

/* =========================================================
   可访问性与动态效果降级
   ========================================================= */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .reveal-ready [data-reveal] { opacity: 1; transform: none; }
  .read-progress__bar { transition: none; }
}