/* ============================================================
   球友会主站 · 共享样式 /assets/site.css
   深蓝绿基底 + 荧光橙强调 + 竖排轨道导航 + 斜切横带
   ============================================================ */

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

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

body {
  margin: 0;
  min-height: 100vh;
  overflow-x: hidden;
}

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

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

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

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

table { border-collapse: collapse; border-spacing: 0; }

/* ---------- 2. Tokens ---------- */
:root {
  /* 色板 */
  --ink:        #0B3B3C;
  --ink-deep:   #072628;
  --felt:       #14676A;
  --flare:      #FF6A1A;
  --flare-soft: #FFA45C;
  --white:      #FBFDFC;
  --mist:       #6E8385;
  --rubber:     #C7302E;
  --ping:       #2FC4B2;
  --fog:        #E4EDEC;

  --on-light:   #0b2b2c;

  /* 派生 */
  --line:       rgba(110, 131, 133, .34);
  --line-soft:  rgba(110, 131, 133, .16);
  --text:       rgba(228, 237, 236, .88);
  --text-dim:   rgba(228, 237, 236, .58);
  --text-strong:#FBFDFC;
  --surface:    rgba(20, 103, 106, .22);
  --surface-2:  rgba(7, 38, 40, .55);

  /* 字体 */
  --sans: "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: ui-monospace, "JetBrains Mono", "IBM Plex Mono", SFMono-Regular, Menlo, Consolas, monospace;

  /* 尺寸 */
  --rail-w: 88px;
  --bar-h: 64px;
  --pad-x: 24px;
  --max-w: 1180px;
  --max-w-wide: 1360px;

  --radius: 3px;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.75;
  font-weight: 400;
  color: var(--text);
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  padding-left: var(--rail-w);
  background-color: var(--ink-deep);
  background-image:
    radial-gradient(115% 78% at 82% -12%, rgba(20, 103, 106, .55) 0%, rgba(11, 59, 60, 0) 62%),
    radial-gradient(88% 58% at 6% 104%, rgba(47, 196, 178, .13) 0%, rgba(11, 59, 60, 0) 70%);
}

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 .5em;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: .005em;
  color: var(--text-strong);
}
h1 { font-size: clamp(2.2rem, 6vw, 3.6rem); font-weight: 900; }
h2 { font-size: clamp(1.5rem, 3.4vw, 2.25rem); }
h3 { font-size: clamp(1.15rem, 2vw, 1.4rem); }

a { color: var(--ping); text-decoration: none; }
a:hover { color: var(--flare-soft); }

strong, b { font-weight: 700; color: var(--text-strong); }

::selection { background: var(--flare); color: var(--on-light); }

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

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

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

#main-content { scroll-margin-top: 80px; }

/* ---------- 4. Skip link ---------- */
.skip-link {
  position: fixed;
  top: 0;
  left: 50%;
  z-index: 300;
  padding: 11px 20px;
  transform: translate(-50%, -130%);
  background: linear-gradient(180deg, var(--flare-soft), var(--flare));
  color: var(--on-light);
  font-size: .875rem;
  font-weight: 700;
  letter-spacing: .06em;
  border-radius: 0 0 var(--radius) var(--radius);
  box-shadow: 0 14px 30px -18px rgba(0, 0, 0, .9);
  transition: transform .18s var(--ease);
}
.skip-link:focus {
  transform: translate(-50%, 0);
  color: var(--on-light);
}

/* ---------- 5. 侧边轨道导航 ---------- */
.site-rail {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 60;
  width: var(--rail-w);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 20px 0 16px;
  background: linear-gradient(180deg, #0d4648 0%, var(--ink) 40%, var(--ink-deep) 100%);
  border-right: 1px solid var(--line);
  color: var(--text-strong);
  transition: box-shadow .22s var(--ease);
}
.site-rail.is-scrolled {
  box-shadow: 12px 0 34px -26px rgba(0, 0, 0, .95);
}

/* 品牌 */
.rail-brand {
  width: 100%;
  padding: 0 8px;
  text-align: center;
}
.rail-brand-link { display: block; color: inherit; text-decoration: none; }
.rail-brand-link:hover .rail-brand-name { color: var(--flare-soft); }
.rail-brand-name {
  display: block;
  font-size: 1.0625rem;
  font-weight: 900;
  letter-spacing: .16em;
  line-height: 1.2;
  color: var(--white);
  transition: color .18s var(--ease);
}
.rail-brand-sub {
  display: block;
  margin-top: 9px;
  font-size: .625rem;
  line-height: 1.6;
  letter-spacing: .02em;
  color: var(--text-dim);
}

/* 移动开关 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 8px 12px;
  background: rgba(255, 106, 26, .1);
  border: 1px solid rgba(255, 106, 26, .45);
  border-radius: 2px;
  color: var(--flare-soft);
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .08em;
  cursor: pointer;
  transition: background-color .18s var(--ease), border-color .18s var(--ease), color .18s var(--ease);
}
.nav-toggle:hover { background: rgba(255, 106, 26, .2); color: var(--white); }
.nav-toggle-bars {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  width: 17px;
  height: 12px;
}
.nav-toggle-bars i {
  display: block;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  transition: transform .2s var(--ease), opacity .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }
.nav-toggle-label { line-height: 1; }

/* 导航主体 */
.rail-nav {
  flex: 1 1 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  min-height: 0;
  padding: 10px 0;
  overflow-y: auto;
  overflow-x: hidden;
  scrollbar-width: thin;
  scrollbar-color: rgba(110, 131, 133, .5) transparent;
}
.rail-nav::-webkit-scrollbar { width: 4px; }
.rail-nav::-webkit-scrollbar-thumb { background: rgba(110, 131, 133, .5); border-radius: 2px; }
.rail-nav::-webkit-scrollbar-track { background: transparent; }

.rail-list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}
.rail-item { display: block; }

.rail-link {
  display: inline-block;
  writing-mode: vertical-rl;
  padding: 10px 7px;
  font-size: .75rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: .16em;
  color: rgba(228, 237, 236, .7);
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 2px;
  transition: color .18s var(--ease), background-color .18s var(--ease), border-color .18s var(--ease);
}
.rail-link:hover {
  color: var(--white);
  background: rgba(20, 103, 106, .62);
  border-color: var(--line);
}
.rail-link[aria-current="page"] {
  color: var(--on-light);
  background: linear-gradient(180deg, var(--flare-soft), var(--flare));
  border-color: var(--flare-soft);
  font-weight: 800;
}

/* 轨道底部 */
.rail-foot {
  width: 100%;
  padding: 0 8px;
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.rail-foot-label {
  display: block;
  margin-top: 6px;
  font-size: .5625rem;
  letter-spacing: .14em;
  color: rgba(228, 237, 236, .48);
  line-height: 1.5;
}
.rail-foot-value {
  display: block;
  font-family: var(--mono);
  font-size: .625rem;
  line-height: 1.5;
  letter-spacing: .01em;
  color: rgba(251, 253, 252, .9);
  overflow-wrap: anywhere;
}
.rail-cta {
  display: block;
  margin-top: 10px;
  padding: 9px 6px;
  background: linear-gradient(180deg, var(--flare-soft), var(--flare));
  color: var(--on-light);
  font-size: .6875rem;
  font-weight: 800;
  letter-spacing: .06em;
  line-height: 1.4;
  border-radius: 2px;
  text-decoration: none;
  transition: filter .18s var(--ease), transform .18s var(--ease);
}
.rail-cta:hover {
  color: var(--on-light);
  filter: brightness(1.08);
  transform: translateY(-2px);
}

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

/* 阅读进度条 */
.rail-meter {
  position: absolute;
  top: 0;
  right: 0;
  width: 3px;
  height: 100%;
  transform: scaleY(0);
  transform-origin: top center;
  background: linear-gradient(180deg, var(--flare-soft), var(--flare) 58%, var(--ping));
  pointer-events: none;
}

/* 移动遮罩 */
.rail-scrim {
  position: fixed;
  inset: var(--bar-h) 0 0 0;
  z-index: 55;
  padding: 0;
  border: 0;
  background: rgba(7, 38, 40, .68);
  opacity: 0;
  visibility: hidden;
  cursor: pointer;
  transition: opacity .2s var(--ease), visibility .2s linear;
}
.rail-scrim[data-open] { opacity: 1; visibility: visible; }

/* ---------- 6. 页脚 ---------- */
.site-foot {
  position: relative;
  margin-top: 96px;
  background: var(--ink-deep);
  border-top: 1px solid var(--line);
  color: var(--text);
}
.site-foot::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 6px;
  background: linear-gradient(90deg,
    var(--flare) 0 16%,
    var(--flare-soft) 16% 28%,
    var(--ping) 28% 44%,
    rgba(110, 131, 133, .55) 44% 100%);
}

.foot-grid {
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 76px 32px 48px;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.7fr;
  gap: 48px 40px;
}

.foot-brand-name {
  margin: 0 0 14px;
  font-size: 1.5rem;
  font-weight: 900;
  letter-spacing: .1em;
  color: var(--white);
}
.foot-brand-note {
  margin: 0;
  max-width: 36ch;
  font-size: .9375rem;
  line-height: 1.85;
  color: var(--text-dim);
}
.foot-brand-stat {
  margin: 18px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--ping);
  font-family: var(--mono);
  font-size: .75rem;
  line-height: 1.8;
  letter-spacing: .02em;
  color: var(--flare-soft);
}

.foot-col-title {
  margin: 0 0 16px;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .2em;
  color: rgba(228, 237, 236, .5);
}
.foot-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.foot-link {
  display: inline-block;
  font-size: .9375rem;
  color: rgba(228, 237, 236, .86);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}
.foot-link:hover {
  color: var(--flare);
  border-bottom-color: rgba(255, 106, 26, .55);
}

.foot-contact { margin: 0; }
.foot-contact-term {
  margin-top: 14px;
  font-size: .6875rem;
  letter-spacing: .16em;
  color: rgba(228, 237, 236, .48);
}
.foot-contact-term:first-of-type { margin-top: 0; }
.foot-contact-value {
  margin: 4px 0 0;
  font-size: .9375rem;
  line-height: 1.7;
  color: rgba(251, 253, 252, .94);
  overflow-wrap: anywhere;
}
.foot-note {
  margin: 16px 0 0;
  font-size: .8125rem;
  line-height: 1.8;
  color: var(--text-dim);
}

.foot-base {
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 22px 32px 36px;
  border-top: 1px solid var(--line-soft);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
}
.foot-legal {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-size: .8125rem;
}
.foot-legal-link {
  color: rgba(228, 237, 236, .78);
  text-decoration: none;
  transition: color .18s var(--ease);
}
.foot-legal-link:hover { color: var(--flare); }
.foot-sep { color: rgba(110, 131, 133, .7); }
.foot-icp {
  margin: 0;
  font-family: var(--mono);
  font-size: .75rem;
  letter-spacing: .06em;
  color: rgba(228, 237, 236, .52);
}

/* ---------- 7. 布局容器 ---------- */
.wrap {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}
.wrap-wide {
  width: 100%;
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

/* ---------- 8. 网格 ---------- */
.grid {
  display: grid;
  gap: 24px;
}
.grid-12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid-4  { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-3  { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-2  { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.span-3  { grid-column: span 3; }
.span-4  { grid-column: span 4; }
.span-5  { grid-column: span 5; }
.span-6  { grid-column: span 6; }
.span-7  { grid-column: span 7; }
.span-8  { grid-column: span 8; }
.span-9  { grid-column: span 9; }
.span-12 { grid-column: span 12; }

.stack { display: flex; flex-direction: column; gap: 16px; }
.row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}
.rule {
  height: 1px;
  border: 0;
  margin: 0;
  background: var(--line-soft);
}

/* ---------- 9. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: .9375rem;
  font-weight: 700;
  letter-spacing: .05em;
  line-height: 1.2;
  border: 1px solid transparent;
  border-radius: 2px;
  text-decoration: none;
  cursor: pointer;
  transition: transform .18s var(--ease), background-color .18s var(--ease),
              border-color .18s var(--ease), color .18s var(--ease), box-shadow .18s var(--ease);
}
.btn--flare {
  background: linear-gradient(180deg, var(--flare-soft), var(--flare));
  color: var(--on-light);
  box-shadow: 0 14px 30px -22px rgba(255, 106, 26, .95);
}
.btn--flare:hover {
  color: var(--on-light);
  transform: translateY(-2px);
  box-shadow: 0 18px 34px -20px rgba(255, 106, 26, .95);
}
.btn--ghost {
  background: transparent;
  color: var(--white);
  border-color: var(--line);
}
.btn--ghost:hover {
  color: var(--ping);
  border-color: var(--ping);
  transform: translateY(-2px);
}

/* ---------- 10. 面包屑 ---------- */
.crumbs { padding: 24px 0 4px; }
.crumbs-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: .8125rem;
  letter-spacing: .04em;
}
.crumbs-item { color: var(--text-dim); }
.crumbs-item + .crumbs-item::before {
  content: "/";
  margin-right: 8px;
  color: rgba(110, 131, 133, .7);
}
.crumbs-item a {
  color: rgba(228, 237, 236, .82);
  text-decoration: none;
  transition: color .18s var(--ease);
}
.crumbs-item a:hover { color: var(--flare); }

/* ---------- 11. 基础组件 ---------- */
.panel {
  position: relative;
  padding: 22px 22px 24px;
  background: rgba(251, 253, 252, .04);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .18s var(--ease), border-color .18s var(--ease),
              box-shadow .18s var(--ease), background-color .18s var(--ease);
}
.panel:hover {
  transform: translateY(-4px);
  border-color: var(--ping);
  background: rgba(20, 103, 106, .24);
  box-shadow: 0 22px 46px -34px rgba(0, 0, 0, .95);
}
.panel--light {
  background: var(--white);
  border-color: #d6e3e2;
  color: var(--on-light);
}
.panel--light:hover {
  background: var(--white);
  border-color: var(--flare);
}
.panel--light .panel-title { color: var(--on-light); }
.panel-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px 14px;
  margin-bottom: 14px;
}
.panel-title {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 800;
  letter-spacing: .02em;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  font-size: .75rem;
  line-height: 1.6;
  letter-spacing: .12em;
  color: rgba(228, 237, 236, .74);
  background: rgba(20, 103, 106, .22);
  border: 1px solid var(--line);
  border-radius: 2px;
  white-space: nowrap;
}
.tag--flare {
  color: var(--flare-soft);
  background: rgba(255, 106, 26, .1);
  border-color: rgba(255, 106, 26, .58);
}
.tag--ping {
  color: var(--ping);
  background: rgba(47, 196, 178, .1);
  border-color: rgba(47, 196, 178, .55);
}
.tag--rubber {
  color: #f0918f;
  background: rgba(199, 48, 46, .14);
  border-color: rgba(199, 48, 46, .62);
}

.stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.stat-value {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.75rem, 3.6vw, 2.875rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--flare);
}
.stat-label {
  font-size: .75rem;
  letter-spacing: .16em;
  color: var(--text-dim);
}

.meter {
  position: relative;
  width: 100%;
  height: 6px;
  background: rgba(110, 131, 133, .22);
  border-radius: 999px;
  overflow: hidden;
}
.meter-fill {
  display: block;
  height: 100%;
  width: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--ping), var(--flare-soft) 62%, var(--flare));
  transition: width .4s var(--ease);
}
.meter-fill.is-filled { width: var(--fill, 0%); }

.table {
  width: 100%;
  font-size: .9375rem;
  text-align: left;
}
.table thead th {
  padding: 11px 14px;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: rgba(228, 237, 236, .62);
  background: var(--surface-2);
  border-bottom: 1px solid var(--line);
  white-space: nowrap;
}
.table td {
  padding: 13px 14px;
  color: var(--text);
  border-bottom: 1px solid var(--line-soft);
  vertical-align: top;
}
.table tbody tr { transition: background-color .18s var(--ease); }
.table tbody tr:hover { background: rgba(20, 103, 106, .22); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 20px;
  margin-bottom: 28px;
}
.section-kicker {
  font-family: var(--mono);
  font-size: .75rem;
  letter-spacing: .22em;
  color: var(--ping);
}
.section-title {
  margin: 0;
  font-size: clamp(1.5rem, 3.2vw, 2.25rem);
  font-weight: 900;
  color: var(--white);
}
.section-note {
  margin: 0;
  flex: 1 1 260px;
  font-size: .875rem;
  color: var(--text-dim);
}

/* ---------- 12. 斜切横带 ---------- */
.band {
  position: relative;
  padding: 84px 0;
}
.band--tight { padding: 56px 0; }
.band > .wrap,
.band > .wrap-wide {
  position: relative;
  z-index: 1;
}
.band--slant::before {
  content: "";
  position: absolute;
  left: 0; right: 0;
  top: 5%; bottom: 5%;
  background: linear-gradient(118deg, rgba(20, 103, 106, .42) 0%, rgba(7, 38, 40, 0) 68%);
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
  transform: skewY(-6deg);
  transform-origin: left center;
  pointer-events: none;
}

/* ---------- 13. 响应式图片容器 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(140deg, rgba(20, 103, 106, .55) 0%, rgba(7, 38, 40, .92) 100%);
}
.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .4s var(--ease), filter .3s var(--ease);
}
.media:hover img { transform: scale(1.03); }
.media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(7, 38, 40, 0) 42%, rgba(7, 38, 40, .8) 100%);
  pointer-events: none;
}
.media--21x9 { aspect-ratio: 21 / 9; }
.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3  { aspect-ratio: 4 / 3; }
.media--1x1  { aspect-ratio: 1 / 1; }

.media-caption {
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 14px;
  z-index: 2;
  font-size: .8125rem;
  line-height: 1.6;
  color: rgba(251, 253, 252, .88);
}

/* ---------- 14. 平板 ---------- */
@media (max-width: 1080px) {
  .foot-grid {
    grid-template-columns: 1fr 1fr;
    gap: 44px 32px;
    padding: 64px 26px 42px;
  }
  .foot-base { padding: 20px 26px 32px; }

  .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .span-3, .span-4 { grid-column: span 6; }
  .span-5, .span-7 { grid-column: span 6; }
}

@media (max-width: 900px) {
  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-12 { gap: 18px; }
  .span-6, .span-8, .span-9 { grid-column: span 12; }
  .band { padding: 64px 0; }
}

/* ---------- 15. 移动端：轨道变顶栏 + 抽屉 ---------- */
@media (max-width: 1023px) {
  body {
    padding-left: 0;
    padding-top: var(--bar-h);
  }

  .site-rail {
    inset: 0 0 auto 0;
    width: 100%;
    height: var(--bar-h);
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 0 14px;
    background: linear-gradient(90deg, var(--ink) 0%, var(--ink-deep) 100%);
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .site-rail.is-scrolled {
    box-shadow: 0 14px 28px -24px rgba(0, 0, 0, .95);
  }

  .rail-brand { width: auto; padding: 0; text-align: left; }
  .rail-brand-name { font-size: 1.0625rem; letter-spacing: .12em; }
  .rail-brand-sub { display: none; }

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

  .rail-nav {
    position: fixed;
    top: var(--bar-h);
    left: 0;
    bottom: 0;
    z-index: 70;
    width: min(330px, 86vw);
    align-items: stretch;
    justify-content: flex-start;
    padding: 18px 16px 32px;
    overflow-y: auto;
    background: linear-gradient(180deg, #0d4648 0%, var(--ink) 45%, var(--ink-deep) 100%);
    border-right: 1px solid var(--line);
    transform: translateX(-104%);
    transition: transform .22s var(--ease);
  }
  .rail-nav[data-open] { transform: translateX(0); }

  .rail-list {
    align-items: stretch;
    gap: 2px;
    width: 100%;
  }
  .rail-item { width: 100%; }
  .rail-link {
    writing-mode: horizontal-tb;
    display: block;
    width: 100%;
    padding: 14px 14px;
    font-size: .9375rem;
    letter-spacing: .08em;
    line-height: 1.4;
    border-radius: 2px;
    border-color: transparent;
  }
  .rail-link[aria-current="page"] { border-radius: 2px; }

  .rail-nav-foot {
    display: flex;
    flex-direction: column;
    gap: 4px;
    margin-top: 24px;
    padding-top: 18px;
    border-top: 1px solid var(--line);
    text-align: left;
  }
  .rail-nav-foot .rail-foot-label { margin-top: 8px; text-align: left; }
  .rail-nav-foot .rail-foot-value { font-size: .8125rem; }
  .rail-nav-foot .rail-cta { margin-top: 14px; padding: 12px; text-align: center; font-size: .8125rem; }

  .rail-foot { display: none; }
  .rail-meter { display: none; }

  #main-content { scroll-margin-top: calc(var(--bar-h) + 12px); }

  .site-foot { margin-top: 72px; }
}

/* ---------- 16. 手机 ---------- */
@media (max-width: 640px) {
  :root { --pad-x: 18px; }

  body { font-size: .9375rem; }

  h1 { font-size: clamp(1.9rem, 9vw, 2.6rem); }

  .foot-grid {
    grid-template-columns: 1fr;
    gap: 34px;
    padding: 48px 18px 32px;
  }
  .foot-base {
    flex-direction: column;
    align-items: flex-start;
    padding: 18px 18px 30px;
  }
  .foot-brand-note { max-width: none; }

  .grid-4, .grid-3, .grid-2 { grid-template-columns: 1fr; }
  .span-3, .span-4, .span-5, .span-6,
  .span-7, .span-8, .span-9 { grid-column: span 12; }

  .band { padding: 52px 0; }
  .band--tight { padding: 40px 0; }
  .panel { padding: 18px 16px 20px; }
  .section-head { margin-bottom: 20px; }
  .btn { width: 100%; padding: 13px 18px; }
}

/* ---------- 17. 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .panel:hover,
  .btn:hover,
  .rail-cta:hover { transform: none; }
  .media:hover img { transform: none; }
  .meter-fill { transition: none; }
}