/* =========================================================
   四季体育 · 共享外壳样式 /assets/site.css
   深墨绿控制台底 + 四季明快强调色 + 大圆角与斜切
   ========================================================= */

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

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

body,
h1, h2, h3, h4, h5,
p, ul, ol, li, figure, blockquote {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

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

:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ---------- 2. 变量 ---------- */
:root {
  --ink: #071E1A;
  --ink-deep: #04140F;
  --panel: #0E2B25;
  --frost: #F4F8F5;
  --spring: #9BE15D;
  --neon: #39FFB6;
  --summer: #1E5AFF;
  --amber: #FFB13B;
  --slate: #8FA39B;
  --pulse: #FF4D6D;
  --line: #DDE8E1;

  --hair: rgba(221, 232, 225, 0.14);
  --hair-strong: rgba(221, 232, 225, 0.32);
  --text-soft: rgba(244, 248, 245, 0.78);

  --radius-xl: 32px;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-pill: 999px;

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

  --wrap: 1200px;
  --pad: clamp(18px, 4vw, 40px);
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  background-color: var(--ink);
  background-image:
    radial-gradient(60ch 42ch at 88% -12%, rgba(57, 255, 182, 0.12), transparent 70%),
    radial-gradient(52ch 40ch at 2% 8%, rgba(30, 90, 255, 0.14), transparent 72%);
  background-attachment: fixed;
  color: var(--frost);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0.01em;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.08em;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.6em;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--slate);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 2px;
  border-radius: 2px;
  background: var(--spring);
}

.display-1 {
  font-size: clamp(40px, 7.2vw, 88px);
  line-height: 1.02;
  letter-spacing: -0.03em;
}

.display-2 {
  font-size: clamp(30px, 4.4vw, 54px);
  line-height: 1.08;
}

.h3 {
  font-size: clamp(19px, 2.2vw, 26px);
  line-height: 1.3;
}

.lede {
  font-size: clamp(16px, 1.5vw, 18px);
  color: var(--text-soft);
  max-width: 62ch;
}

/* ---------- 4. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6em;
  padding: 12px 22px;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  white-space: nowrap;
  transition: transform 0.22s var(--ease), background 0.22s var(--ease),
    color 0.22s var(--ease), box-shadow 0.26s var(--ease);
}

.btn:hover { transform: translateY(-2px); }

.btn--primary {
  background: var(--spring);
  color: #06251C;
  box-shadow: 0 14px 34px -18px rgba(155, 225, 93, 0.9);
}

.btn--primary:hover { background: var(--neon); }

.btn--ghost {
  border-color: rgba(57, 255, 182, 0.55);
  background: rgba(57, 255, 182, 0.07);
  color: var(--neon);
}

.btn--ghost:hover {
  background: var(--neon);
  color: #052B22;
}

.btn--amber {
  background: var(--amber);
  color: #2A1700;
}

.btn--amber:hover { background: #FFC56B; }

.btn--sm {
  padding: 8px 16px;
  font-size: 13px;
}

/* ---------- 5. 头部：双层信息导航 ---------- */
.masthead {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(7, 30, 26, 0.94);
  border-bottom: 1px solid var(--hair);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
}

.rail {
  position: relative;
  height: 3px;
  background: rgba(221, 232, 225, 0.08);
}

.rail__bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--spring), var(--neon) 45%, var(--summer) 78%, var(--amber));
  transition: transform 0.12s linear;
}

.skip-link {
  position: absolute;
  left: 12px;
  top: -72px;
  z-index: 90;
  padding: 10px 20px;
  border-radius: 0 0 14px 14px;
  background: var(--spring);
  color: #06251C;
  font-weight: 800;
  font-size: 14px;
  transition: top 0.2s var(--ease);
}

.skip-link:focus { top: 3px; }

.masthead__utility { border-bottom: 1px solid var(--hair); }

.masthead__utility-inner {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  min-height: 78px;
  padding-block: 12px;
}

.brandmark {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

.brandmark__glyph {
  position: relative;
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: conic-gradient(from 205deg, var(--spring), var(--neon), var(--summer), var(--amber), var(--spring));
  box-shadow: 0 8px 22px -12px rgba(57, 255, 182, 0.95);
}

.brandmark__glyph::after {
  content: "SJ";
  position: absolute;
  inset: 4px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--ink);
  color: var(--neon);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
}

.brandmark__text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brandmark__name {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.05em;
}

.brandmark__sub {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  color: var(--slate);
}

.masthead__tools {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: clamp(10px, 2vw, 22px);
  margin-left: auto;
}

.masthead__status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: rgba(221, 232, 225, 0.72);
}

.masthead__pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--pulse);
  box-shadow: 0 0 0 3px rgba(255, 77, 109, 0.18);
  animation: pulseDot 2.6s infinite;
}

@keyframes pulseDot {
  0%, 100% { box-shadow: 0 0 0 3px rgba(255, 77, 109, 0.18); }
  50% { box-shadow: 0 0 0 7px rgba(255, 77, 109, 0); }
}

.season-dial {
  display: flex;
  gap: 6px;
}

.season-dial__item {
  position: relative;
  padding: 5px 11px 5px 23px;
  border: 1px solid var(--hair);
  border-radius: var(--radius-pill);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: rgba(244, 248, 245, 0.82);
}

.season-dial__item::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 50%;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  transform: translateY(-50%);
}

.season-dial__item--spring::before { background: var(--spring); }
.season-dial__item--summer::before { background: var(--summer); }
.season-dial__item--autumn::before { background: var(--amber); }
.season-dial__item--winter::before { background: var(--frost); }

.masthead__cta { flex: 0 0 auto; }

.masthead__nav-inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: 16px;
  padding-block: 8px;
}

.nav {
  flex: 1 1 auto;
  min-width: 0;
}

.nav__list {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 2px;
}

.nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 16px;
  border-radius: var(--radius-pill);
  font-size: 15px;
  font-weight: 600;
  color: rgba(244, 248, 245, 0.82);
  transition: background 0.2s var(--ease), color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.nav__link:hover {
  background: rgba(221, 232, 225, 0.09);
  color: var(--frost);
}

.nav__num {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  color: var(--slate);
}

.nav__link--anchor {
  background: var(--neon);
  color: #052B22;
  box-shadow: 0 10px 28px -16px rgba(57, 255, 182, 0.95);
}

.nav__link--anchor .nav__num { color: rgba(5, 43, 34, 0.62); }

.nav__link--anchor:hover {
  background: var(--spring);
  color: #052B22;
}

.nav__link[aria-current="page"] {
  color: var(--spring);
  box-shadow: inset 0 0 0 1px rgba(155, 225, 93, 0.5);
}

.nav__link--anchor[aria-current="page"] {
  color: #052B22;
  box-shadow: inset 0 0 0 2px rgba(5, 43, 34, 0.4), 0 10px 28px -16px rgba(57, 255, 182, 0.95);
}

.masthead__index {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--slate);
  white-space: nowrap;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  border: 1px solid var(--hair-strong);
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 700;
  color: var(--frost);
}

.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  gap: 4px;
  width: 18px;
}

.nav-toggle__bars span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--neon);
  transition: transform 0.24s var(--ease), opacity 0.2s linear;
}

.nav-toggle[aria-expanded="true"] {
  border-color: rgba(57, 255, 182, 0.6);
  background: rgba(57, 255, 182, 0.1);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ---------- 6. 页脚：数据中枢底舱 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background: linear-gradient(180deg, #071E1A 0%, #04140F 78%);
  border-top: 1px solid var(--hair);
}

.site-footer::before {
  content: "";
  position: absolute;
  left: -14ch;
  top: -18ch;
  width: 52ch;
  height: 52ch;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(57, 255, 182, 0.14), transparent 68%);
  pointer-events: none;
}

.season-ribbon {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2px;
  height: 6px;
}

.season-ribbon__seg { display: block; height: 100%; }
.season-ribbon__seg--spring { background: var(--spring); }
.season-ribbon__seg--summer { background: var(--summer); }
.season-ribbon__seg--autumn { background: var(--amber); }
.season-ribbon__seg--winter { background: var(--line); }

.site-footer__body {
  position: relative;
  display: grid;
  grid-template-columns: 1.4fr 1.5fr 1.3fr;
  gap: clamp(26px, 4vw, 56px);
  padding-block: clamp(40px, 6vw, 76px);
}

.site-footer__wordmark {
  font-family: var(--font-display);
  font-size: clamp(30px, 4.4vw, 54px);
  font-weight: 800;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--frost);
}

.site-footer__tagline {
  margin-top: 14px;
  max-width: 26ch;
  font-size: 15px;
  color: rgba(244, 248, 245, 0.7);
}

.footer__coords {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 24px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--slate);
}

.footer__coords li {
  padding-left: 12px;
  border-left: 2px solid rgba(155, 225, 93, 0.6);
}

.site-footer__nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(16px, 3vw, 32px);
  align-content: start;
}

.footer__col-title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--spring);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer__link {
  display: inline-block;
  padding: 7px 0;
  font-size: 15px;
  color: rgba(244, 248, 245, 0.78);
  transition: color 0.2s var(--ease), transform 0.2s var(--ease);
}

.footer__link:hover {
  color: var(--neon);
  transform: translateX(4px);
}

.contact-list {
  display: flex;
  flex-direction: column;
}

.contact-row {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 10px;
  align-items: baseline;
  padding: 10px 0;
  border-bottom: 1px dashed var(--hair);
  font-size: 14px;
}

.contact-row__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--slate);
}

.contact-row__value {
  color: rgba(244, 248, 245, 0.9);
  word-break: break-word;
}

.site-footer__note {
  margin-top: 16px;
  max-width: 34ch;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(143, 163, 155, 0.95);
}

.site-footer__legal {
  border-top: 1px solid var(--hair);
  background: rgba(4, 20, 15, 0.6);
}

.site-footer__legal-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 26px;
  padding-block: 18px;
  font-size: 12.5px;
  color: var(--slate);
}

.site-footer__copy {
  margin-right: auto;
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

.legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.legal-links a {
  color: rgba(244, 248, 245, 0.72);
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.legal-links a:hover {
  color: var(--neon);
  border-bottom-color: var(--neon);
}

.site-footer__icp {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

/* ---------- 7. 页面通用分区与组件 ---------- */
.section {
  position: relative;
  padding-block: clamp(48px, 7vw, 96px);
}

.section--panel { background: var(--panel); }

.section--frost {
  background: var(--frost);
  color: #0B241E;
}

.section--frost .lede { color: #3D564D; }
.section--frost .eyebrow { color: #547066; }
.section--frost .chapter__note { color: #547066; }
.section--frost .card {
  background: #FFFFFF;
  border-color: #D5E3DA;
  color: #0B241E;
}
.section--frost .card__meta { color: #4B655B; }

.section--edge { border-top: 1px solid var(--hair); }

.chapter {
  display: flex;
  align-items: flex-start;
  gap: clamp(12px, 2vw, 24px);
  margin-bottom: 28px;
}

.chapter__no {
  font-family: var(--font-mono);
  font-size: clamp(34px, 5vw, 56px);
  font-weight: 700;
  line-height: 0.9;
  letter-spacing: -0.03em;
  color: transparent;
  -webkit-text-stroke: 1.5px rgba(155, 225, 93, 0.75);
}

.chapter__body {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.chapter__title { font-size: clamp(25px, 3.2vw, 40px); }

.chapter__note {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--slate);
}

.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 28px);
}

.grid--5-7 { grid-template-columns: 5fr 7fr; }
.grid--7-5 { grid-template-columns: 7fr 5fr; }
.grid--3-6-3 { grid-template-columns: 3fr 6fr 3fr; }
.grid--trio { grid-template-columns: repeat(3, 1fr); }
.grid--duo { grid-template-columns: repeat(2, 1fr); }

.card {
  position: relative;
  padding: clamp(18px, 2.4vw, 28px);
  border: 1px solid var(--hair);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(14, 43, 37, 0.96), rgba(7, 30, 26, 0.96));
  transition: transform 0.26s var(--ease), border-color 0.26s var(--ease),
    box-shadow 0.26s var(--ease);
}

.card:hover {
  transform: translateY(-3px);
  border-color: rgba(57, 255, 182, 0.42);
  box-shadow: 0 26px 54px -36px rgba(57, 255, 182, 0.75);
}

.card__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--slate);
}

.card__title {
  margin-top: 8px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  line-height: 1.35;
  letter-spacing: -0.01em;
}

.card__meta {
  margin-top: 6px;
  font-size: 14px;
  color: rgba(244, 248, 245, 0.66);
}

.panel {
  padding: clamp(20px, 3vw, 36px);
  border: 1px solid var(--hair);
  border-radius: var(--radius-xl);
  background: var(--panel);
}

.panel--cut {
  -webkit-clip-path: polygon(0 0, 100% 0, 100% calc(100% - 30px), 0 100%);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 30px), 0 100%);
}

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border: 1px solid var(--hair-strong);
  border-radius: var(--radius-pill);
  background: rgba(221, 232, 225, 0.04);
  font-size: 13px;
  color: rgba(244, 248, 245, 0.85);
}

.pill--spring {
  border-color: rgba(155, 225, 93, 0.5);
  color: var(--spring);
}

.pill--amber {
  border-color: rgba(255, 177, 59, 0.55);
  color: var(--amber);
}

.pill--alert {
  border-color: rgba(255, 77, 109, 0.55);
  color: var(--pulse);
}

.stat { display: block; }

.stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 3.6vw, 44px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--spring);
}

.stat__label {
  display: block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--slate);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 18px;
  font-size: 13px;
  color: var(--slate);
}

.breadcrumb a { color: rgba(244, 248, 245, 0.75); }
.breadcrumb a:hover { color: var(--neon); }
.breadcrumb__sep { color: rgba(143, 163, 155, 0.6); }

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 700;
  color: var(--spring);
}

.link-arrow::after {
  content: "→";
  transition: transform 0.2s var(--ease);
}

.link-arrow:hover::after { transform: translateX(4px); }

.status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.status::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.status--ok {
  color: var(--spring);
  background: rgba(155, 225, 93, 0.12);
}

.status--alert {
  color: var(--pulse);
  background: rgba(255, 77, 109, 0.14);
}

.divider {
  height: 1px;
  margin-block: clamp(24px, 4vw, 48px);
  border: 0;
  background: var(--hair);
}

/* ---------- 8. 可复用图片容器（页面阶段放占位图） ---------- */
.media-frame {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--hair);
  border-radius: var(--radius-lg);
  background: linear-gradient(140deg, #0E2B25, #071E1A 58%, #0B2E33);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(57, 255, 182, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(57, 255, 182, 0.1) 1px, transparent 1px);
  background-size: 48px 48px;
  opacity: 0.5;
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame__caption {
  position: absolute;
  left: 16px;
  bottom: 14px;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(244, 248, 245, 0.85);
}

/* ---------- 9. 滚动显现协议 ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.42s var(--ease), transform 0.42s var(--ease);
}

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

/* ---------- 10. 响应式 ---------- */
@media (max-width: 1080px) {
  .masthead__status { display: none; }
  .site-footer__body { grid-template-columns: 1fr 1fr; }
  .site-footer__contact { grid-column: span 2; }
}

@media (max-width: 900px) {
  .masthead__utility-inner { min-height: 66px; }
  .season-dial { display: none; }
  .brandmark__glyph { width: 38px; height: 38px; }
  .brandmark__name { font-size: 18px; }

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

  .masthead__index { display: none; }

  .masthead__nav-inner { padding-block: 10px; }

  .nav {
    position: absolute;
    top: calc(100% + 1px);
    left: 0;
    right: 0;
    display: none;
    max-height: calc(100vh - 130px);
    overflow-y: auto;
    padding: 14px var(--pad) 22px;
    border: 1px solid var(--hair);
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
    background: var(--panel);
    box-shadow: 0 34px 64px -34px #000000;
  }

  .nav[data-open="true"] {
    display: block;
    animation: navIn 0.24s var(--ease);
  }

  @keyframes navIn {
    from { opacity: 0; transform: translateY(-8px); }
    to { opacity: 1; transform: none; }
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .nav__link {
    justify-content: flex-start;
    padding: 13px 16px;
    border-radius: var(--radius-md);
    font-size: 16px;
  }

  .grid--5-7,
  .grid--7-5,
  .grid--3-6-3,
  .grid--trio,
  .grid--duo {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .brandmark__sub { font-size: 9.5px; letter-spacing: 0.12em; }
  .masthead__cta { padding: 8px 14px; font-size: 12.5px; }

  .site-footer__body { grid-template-columns: 1fr; }
  .site-footer__contact { grid-column: auto; }
  .site-footer__nav { grid-template-columns: 1fr 1fr; }
  .site-footer__legal-inner { flex-direction: column; align-items: flex-start; gap: 10px; }
  .site-footer__copy { margin-right: 0; }
  .contact-row { grid-template-columns: 48px 1fr; }
}

/* ---------- 11. 无障碍：减少动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

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

  .rail__bar { transition: none; }
  .btn:hover,
  .card:hover,
  .footer__link:hover { transform: none; }
}