/* ============================================================
   火狐体育 · 共享样式表 /assets/site.css
   近单色橙系 + 夜灰底 + 荧光绿/天蓝状态色
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-padding-top: 104px;
}

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

body {
  margin: 0;
  background: #0E1014;
  color: #FFFFFF;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img, svg, video { max-width: 100%; display: block; }
ul, ol { margin: 0; padding: 0; }

h1, h2, h3, h4, h5, h6 { margin: 0; }
p { margin: 0; }

a { color: inherit; }

button { font: inherit; }

/* ---------- 2. Tokens ---------- */
:root {
  --fire: #FF5B1B;
  --fire-deep: #C93D06;
  --fire-soft: #FFB07A;
  --night: #15171C;
  --night-deep: #0E1014;
  --slate: #3A3F4A;
  --white: #FFFFFF;
  --ink-2: #D8DCE3;
  --ink-3: #9AA1AE;
  --lime: #B7FF3C;
  --sky: #3FC4FF;
  --mist: #E8EAED;
  --alert: #FF8A3D;

  --font-head: "Noto Sans SC", "HarmonyOS Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-body: "Noto Sans SC", "HarmonyOS Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  --rail-w: 1320px;
  --edge: clamp(20px, 4vw, 56px);
  --header-edge: clamp(12px, 2.5vw, 30px);

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

  --shell: rgba(21, 23, 28, 0.86);
  --shell-solid: rgba(21, 23, 28, 0.97);
  --hairline: rgba(255, 255, 255, 0.10);
  --hairline-fire: rgba(255, 176, 122, 0.24);
  --shadow-fire: 0 10px 28px rgba(255, 91, 27, 0.32);
}

/* ---------- 3. 中文排版基础 ---------- */
.display {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(2.2rem, 5vw, 4.2rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
  color: #FFFFFF;
}

.section-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin: 0;
}

.lead {
  font-size: clamp(1.02rem, 1.4vw, 1.16rem);
  line-height: 1.85;
  color: var(--ink-2);
  max-width: 34em;
}

.mono { font-family: var(--font-mono); letter-spacing: 0.06em; }
.text-lime { color: var(--lime); }
.text-sky { color: var(--sky); }

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

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

/* ---------- 4. 容器 / 章节 / 分屏 ---------- */
.container {
  width: min(var(--rail-w), calc(100% - var(--edge) * 2));
  margin-inline: auto;
}

.container--narrow {
  width: min(880px, calc(100% - var(--edge) * 2));
  margin-inline: auto;
}

.section {
  position: relative;
  padding: clamp(56px, 7.5vw, 112px) 0;
}

.section--tight { padding: clamp(36px, 4.5vw, 64px) 0; }

.section--night {
  background: var(--night);
  color: #FFFFFF;
}

.section--mist {
  background: var(--mist);
  color: var(--night);
}

.section--mist .section-title,
.section--mist .display { color: var(--night); }

.section--mist .lead,
.section--mist .prose { color: #41464F; }

.section--mist .stat-value { color: var(--night); }
.section--mist .stat-label { color: #5C636E; }

.section--mist .card {
  background: #FFFFFF;
  border-color: rgba(21, 23, 28, 0.10);
  color: var(--night);
}

.section--mist .rail-item { border-left-color: rgba(21, 23, 28, 0.14); }
.section--mist .rail-dot { background: #FFFFFF; }

/* 章节刻度线：滚动高亮 */
.section[data-section]::before {
  content: "";
  position: absolute;
  left: 0; top: 12%; bottom: 12%;
  width: 3px;
  background: linear-gradient(180deg, var(--fire) 0%, rgba(255, 91, 27, 0) 100%);
  opacity: 0;
  transform: scaleY(0.4);
  transform-origin: top center;
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.section[data-section][data-active="true"]::before {
  opacity: 1;
  transform: none;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 58fr) minmax(0, 42fr);
  gap: clamp(24px, 4vw, 64px);
  align-items: start;
}

.split--flip { grid-template-columns: minmax(0, 42fr) minmax(0, 58fr); }

.grid {
  display: grid;
  gap: clamp(16px, 2vw, 24px);
  grid-template-columns: repeat(auto-fit, minmax(min(260px, 100%), 1fr));
}

/* ---------- 5. 显现动效 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
  line-height: 1;
  letter-spacing: 0.01em;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.btn--sm { padding: 10px 16px; font-size: 14px; }

.btn--fire {
  background: var(--fire);
  color: #FFFFFF;
  box-shadow: var(--shadow-fire);
}

.btn--fire:hover { background: var(--fire-deep); transform: translateY(-1px); }
.btn--fire:active { background: var(--fire-deep); transform: none; }

.btn--ghost {
  background: transparent;
  color: #FFFFFF;
  border-color: rgba(255, 255, 255, 0.26);
}

.btn--ghost:hover {
  color: var(--fire-soft);
  border-color: var(--fire-soft);
  background: rgba(255, 91, 27, 0.10);
}

.btn--tonal {
  background: rgba(255, 91, 27, 0.12);
  color: var(--fire-deep);
  border-color: rgba(255, 91, 27, 0.28);
}

.btn--tonal:hover { background: rgba(255, 91, 27, 0.2); }

/* ---------- 7. 标签 / 数据 / 卡片 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  line-height: 1;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--fire);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
}

.eyebrow--lime { color: var(--lime); }
.eyebrow--sky { color: var(--sky); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border-radius: var(--radius-pill);
  border: 1px solid currentColor;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: transparent;
}

.tag--fire { color: var(--fire); background: rgba(255, 91, 27, 0.10); }
.tag--lime { color: var(--lime); background: rgba(183, 255, 60, 0.08); }
.tag--sky { color: var(--sky); background: rgba(63, 196, 255, 0.08); }
.tag--alert { color: var(--alert); background: rgba(255, 138, 61, 0.10); }

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

.stat-value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.7rem, 3.6vw, 2.6rem);
  line-height: 1;
  letter-spacing: 0.06em;
  color: #FFFFFF;
}

.stat-value--up { color: var(--lime); }
.stat-value--down { color: var(--sky); }

.stat-label {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink-3);
}

.card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(20px, 2.4vw, 28px);
  border-radius: var(--radius-lg);
  border: 1px solid var(--hairline);
  background: rgba(255, 255, 255, 0.03);
  color: inherit;
  transition: border-color 0.2s ease, transform 0.2s ease, background-color 0.2s ease;
}

.card:hover {
  border-color: var(--hairline-fire);
  transform: translateY(-3px);
}

.card-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1.14rem;
  line-height: 1.35;
  letter-spacing: -0.01em;
}

.card-meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

/* ---------- 8. 时间轴 / 服务路径 ---------- */
.rail {
  list-style: none;
  margin: 0;
  padding: 0;
}

.rail-item {
  position: relative;
  padding: 0 0 28px 34px;
  border-left: 2px solid rgba(255, 255, 255, 0.12);
}

.rail-item:last-child { border-left-color: transparent; padding-bottom: 0; }

.rail-dot {
  position: absolute;
  left: -9px;
  top: 4px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--night);
  border: 3px solid var(--fire);
  transition: border-color 0.4s ease, box-shadow 0.4s ease;
}

.rail-item[data-active="true"] { border-left-color: var(--fire); }

.rail-item[data-active="true"] .rail-dot {
  border-color: var(--lime);
  box-shadow: 0 0 0 5px rgba(183, 255, 60, 0.16);
}

.rail-time {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  line-height: 1.8;
  letter-spacing: 0.1em;
  color: var(--fire-soft);
}

/* ---------- 9. 正文列 ---------- */
.prose {
  max-width: 36em;
  font-size: 17.5px;
  line-height: 1.8;
  color: var(--ink-2);
}

.prose > * + * { margin-top: 1.05em; }

.prose h2,
.prose h3 {
  font-family: var(--font-head);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.3;
  color: #FFFFFF;
  margin-top: 1.6em;
}

.prose h2 { font-size: 1.45rem; }
.prose h3 { font-size: 1.16rem; }

.prose a {
  color: var(--sky);
  text-decoration: none;
  border-bottom: 1px solid rgba(63, 196, 255, 0.45);
}

.prose a:hover { border-bottom-color: var(--sky); }

.prose--light { color: #41464F; }
.prose--light h2,
.prose--light h3 { color: var(--night); }

/* ---------- 10. 图片容器 ---------- */
.media {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: var(--slate);
  isolation: isolate;
}

.media--wide { aspect-ratio: 21 / 9; }
.media--tall { aspect-ratio: 3 / 4; }

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

.media--grid::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0.55;
  background-image:
    linear-gradient(rgba(255, 176, 122, 0.16) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 176, 122, 0.16) 1px, transparent 1px);
  background-size: 44px 44px;
}

.media-caption {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

/* ---------- 11. 面包屑 ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.breadcrumb li { display: inline-flex; align-items: center; gap: 10px; }

.breadcrumb li + li::before {
  content: "/";
  color: var(--slate);
}

.breadcrumb a { text-decoration: none; color: inherit; }
.breadcrumb a:hover { color: var(--sky); }
.breadcrumb [aria-current="page"] { color: #FFFFFF; }

/* ---------- 12. 跳至主内容 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 12px 18px;
  border-radius: 10px;
  background: var(--lime);
  color: var(--night);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 14px;
  text-decoration: none;
  transform: translateY(-240%);
  transition: transform 0.2s ease;
}

.skip-link:focus { transform: none; }

/* ---------- 13. 阅读进度 ---------- */
.fx-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 120;
  width: 100%;
  height: 3px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--fire) 0%, var(--fire-soft) 62%, var(--lime) 100%);
  pointer-events: none;
  will-change: transform;
}

/* ---------- 14. 头部 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 60;
  padding: 16px 0 0;
  pointer-events: none;
  transition: padding 0.3s ease;
}

.site-header[data-scrolled="true"] { padding-top: 8px; }

.header-rail {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  width: min(var(--rail-w), calc(100% - var(--header-edge) * 2));
  margin: 0 auto;
  pointer-events: auto;
}

.island {
  display: flex;
  align-items: center;
  gap: 10px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--hairline-fire);
  background: var(--shell);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: background-color 0.3s ease, border-color 0.3s ease, padding 0.3s ease;
}

.island--brand { padding: 7px 20px 7px 12px; }
.island--actions { padding: 6px; margin-left: 0; gap: 6px; }

.site-header[data-scrolled="true"] .island,
.site-header[data-scrolled="true"] .site-nav {
  background: var(--shell-solid);
  border-color: rgba(255, 176, 122, 0.34);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: #FFFFFF;
}

.brand-flame {
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  border-radius: 62% 38% 56% 44% / 48% 56% 44% 52%;
  background: linear-gradient(150deg, var(--fire) 0%, var(--fire-deep) 78%);
  box-shadow: 0 0 0 4px rgba(255, 91, 27, 0.16);
  transform: rotate(-12deg);
}

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

.brand-text {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.1;
  letter-spacing: 0.02em;
}

.brand-line {
  font-family: var(--font-mono);
  font-size: 10.5px;
  line-height: 1.2;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.56);
  white-space: nowrap;
}

/* 栏目岛 */
.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-inline: auto;
  padding: 6px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--hairline-fire);
  background: var(--shell);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-link {
  display: block;
  padding: 9px 16px;
  border-radius: var(--radius-pill);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
  line-height: 1.2;
  color: rgba(255, 255, 255, 0.72);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.2s ease, background-color 0.2s ease, box-shadow 0.2s ease;
}

.nav-link:hover {
  color: #FFFFFF;
  background: rgba(255, 91, 27, 0.16);
}

.nav-link[aria-current="page"] {
  color: #FFFFFF;
  background: var(--fire);
  box-shadow: var(--shadow-fire);
}

.nav-actions { display: none; }

/* 移动端开关 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  margin-left: auto;
  height: 48px;
  padding: 0 18px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--hairline-fire);
  background: var(--shell-solid);
  color: #FFFFFF;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.1em;
  cursor: pointer;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.nav-toggle:hover { border-color: var(--fire-soft); }

.nav-toggle-bars {
  position: relative;
  display: block;
  width: 18px;
  height: 12px;
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.25s ease, top 0.25s ease;
}

.nav-toggle-bars::before { top: 0; }
.nav-toggle-bars::after { top: 10px; }

.nav-toggle[aria-expanded="true"] .nav-toggle-bars::before {
  top: 5px;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars::after {
  top: 5px;
  transform: rotate(-45deg);
}

/* ---------- 15. 页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  margin-top: clamp(48px, 6vw, 96px);
  padding: clamp(56px, 7vw, 96px) 0 28px;
  background: var(--night);
  color: var(--ink-2);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -12%;
  width: 58%;
  height: 150%;
  pointer-events: none;
  background: linear-gradient(158deg, rgba(255, 91, 27, 0.18) 0%, rgba(255, 91, 27, 0) 62%);
  transform: skewX(-14deg);
}

.footer-slash {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(
    90deg,
    var(--fire) 0%,
    var(--fire) 44%,
    rgba(255, 91, 27, 0) 44%,
    rgba(255, 91, 27, 0) 47%,
    var(--fire-soft) 47%,
    var(--fire-soft) 100%
  );
}

.footer-main {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.45fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 18px;
}

.brand--footer { align-items: center; }
.brand--footer .brand-text { font-size: 20px; }
.brand--footer .brand-line { color: rgba(255, 255, 255, 0.5); }

.footer-note {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-3);
  max-width: 22em;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}

.footer-col-title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--fire-soft);
}

.footer-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-list a {
  display: inline-block;
  font-size: 15.5px;
  line-height: 1.6;
  color: var(--ink-2);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.footer-list a:hover {
  color: #FFFFFF;
  border-bottom-color: var(--fire);
}

.footer-list a[aria-current="page"] {
  color: var(--fire-soft);
  border-bottom-color: var(--fire-soft);
}

.footer-contact-strip {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: clamp(40px, 5vw, 64px);
  padding-top: clamp(24px, 3vw, 34px);
  border-top: 1px solid var(--hairline);
}

.footer-contact-item {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
}

.footer-label {
  display: block;
  width: 100%;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.footer-value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 14.5px;
  letter-spacing: 0.05em;
  color: #FFFFFF;
  word-break: break-all;
}

.copy-btn {
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(183, 255, 60, 0.4);
  background: transparent;
  color: var(--lime);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 11.5px;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.copy-btn:hover { background: rgba(183, 255, 60, 0.12); }

.copy-btn[data-copied="true"] {
  background: var(--lime);
  border-color: var(--lime);
  color: var(--night);
}

.footer-contact-note {
  grid-column: 1 / -1;
  font-size: 13.5px;
  color: var(--ink-3);
}

.footer-base {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: clamp(28px, 3.5vw, 44px);
  padding-top: 20px;
  border-top: 1px solid var(--hairline);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--ink-3);
}

.footer-copy,
.footer-icp { margin: 0; }

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1180px) {
  .nav-link { padding: 9px 12px; font-size: 14.5px; }
  .brand-line { display: none; }
}

@media (max-width: 1080px) {
  .island--actions .btn--ghost { display: none; }
}

@media (max-width: 900px) {
  html { scroll-padding-top: 88px; }

  .header-rail { gap: 8px; }

  .site-header { padding-top: 10px; }
  .site-header[data-scrolled="true"] { padding-top: 6px; }

  .island--brand { padding: 7px 16px 7px 11px; }
  .island--actions { display: none; }

  .brand-line { display: none; }

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

  .site-nav {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    display: block;
    margin: 0;
    padding: 12px;
    border-radius: 26px;
    border: 1px solid var(--hairline-fire);
    background: var(--shell-solid);
    box-shadow: 0 24px 60px rgba(0, 0, 0, 0.45);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    max-height: 0;
    overflow: hidden;
    transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s ease, max-height 0.28s ease;
  }

  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: none;
    max-height: min(72vh, 560px);
    overflow-y: auto;
  }

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

  .nav-link {
    padding: 13px 16px;
    border-radius: 16px;
    font-size: 16px;
  }

  .nav-actions {
    display: grid;
    gap: 10px;
    margin-top: 12px;
    padding-top: 14px;
    border-top: 1px solid var(--hairline);
  }

  .nav-actions .btn { width: 100%; }

  .split,
  .split--flip { grid-template-columns: 1fr; }

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

@media (max-width: 560px) {
  body { font-size: 16.5px; }

  .nav-toggle-label { display: none; }
  .nav-toggle { padding: 0 16px; }

  .footer-cols { grid-template-columns: 1fr; }
  .footer-contact-strip { grid-template-columns: 1fr; }

  .btn { width: 100%; }
  .island--actions .btn,
  .nav-actions .btn { width: auto; }
  .footer-brand .btn { width: auto; }
}

/* ---------- 17. 焦点与减弱动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  html { scroll-behavior: auto; }

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