/* ==========================================================================
   星空体育 · /assets/site.css
   共享层：reset / 设计变量 / 中文排版 / 悬浮胶囊头部 / 地平线页脚 / 通用组件
   ========================================================================== */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 120px;
}

body, h1, h2, h3, h4, h5, p, figure, blockquote, ul, ol, dl, dd { margin: 0; }
ul[class], ol[class] { margin: 0; padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; }
button, input, textarea, select { font: inherit; }
a { color: inherit; }
table { border-collapse: collapse; width: 100%; }

/* ---------- 2. 设计变量 ---------- */
:root {
  /* 色彩 —— 近单色深空体系 */
  --ink-900: #060A18;
  --ink-800: #0F1A30;
  --ink-700: #14343A;
  --silver:   #C9D6E8;
  --white:    #F2F6FC;
  --mist:     #7C90AE;
  --cyan:     #3BE3D0;
  --cyan-deep:#1B8F9E;
  --gold:     #F6B94A;
  --gold-ink: #141006;

  --line:        rgba(124, 144, 174, 0.26);
  --line-soft:   rgba(201, 214, 232, 0.10);
  --line-strong: rgba(59, 227, 208, 0.34);

  /* 尺寸与节奏 */
  --wrap: 1200px;
  --gutter: clamp(18px, 4vw, 48px);
  --radius-lg: 26px;
  --radius-md: 16px;
  --radius-pill: 999px;

  --shadow-hard: 8px 8px 0 rgba(6, 10, 24, 0.9);
  --shadow-soft: 0 24px 60px -30px rgba(6, 10, 24, 1);

  --font-sans: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

/* ---------- 3. 全局底：高原星空天幕 ---------- */
body {
  min-height: 100vh;
  font-family: var(--font-sans);
  font-size: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  line-height: 1.7;
  color: var(--silver);
  background-color: var(--ink-900);
  background-image:
    radial-gradient(1.5px 1.5px at 12% 18%, rgba(201, 214, 232, 0.45) 50%, transparent 51%),
    radial-gradient(1.5px 1.5px at 78% 42%, rgba(59, 227, 208, 0.38) 50%, transparent 51%),
    radial-gradient(1px 1px at 46% 72%, rgba(201, 214, 232, 0.30) 50%, transparent 51%),
    radial-gradient(1px 1px at 88% 86%, rgba(246, 185, 74, 0.30) 50%, transparent 51%),
    radial-gradient(1px 1px at 30% 52%, rgba(201, 214, 232, 0.22) 50%, transparent 51%);
  background-repeat: repeat;
  background-size: 320px 320px, 420px 420px, 260px 260px, 500px 500px, 640px 640px;
  -webkit-font-smoothing: antialiased;
}

body.nav-open { overflow: hidden; }

h1, h2, h3, h4, h5 {
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.14;
  color: var(--white);
}

h1 { font-size: clamp(2.4rem, 6vw, 5.2rem); }
h2 { font-size: clamp(1.6rem, 3vw, 2.6rem); }
h3 { font-size: clamp(1.1rem, 1.8vw, 1.4rem); }

p { text-wrap: pretty; }

strong, b { color: var(--white); font-weight: 800; }

::selection { background: rgba(59, 227, 208, 0.3); color: var(--white); }

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

#main-content { display: block; }
#main-content:focus-visible { outline: 2px solid var(--cyan); outline-offset: -4px; }

/* ---------- 4. 跳至主要内容 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 50%;
  z-index: 200;
  transform: translate(-50%, -180%);
  padding: 11px 22px;
  border-radius: var(--radius-pill);
  background: var(--gold);
  color: var(--gold-ink);
  font-size: 0.84rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-decoration: none;
  box-shadow: 0 10px 30px -10px rgba(6, 10, 24, 0.9);
  transition: transform 0.22s ease;
}
.skip-link:focus,
.skip-link:focus-visible { transform: translate(-50%, 0); }

/* ---------- 5. 悬浮胶囊头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  padding: clamp(10px, 1.6vw, 18px) var(--gutter) 8px;
  pointer-events: none;
}

.header-shell {
  pointer-events: auto;
  position: relative;
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.8vw, 24px);
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 9px 10px 9px 16px;
  border: 2px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: rgba(15, 26, 48, 0.86);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  box-shadow:
    0 22px 46px -30px rgba(6, 10, 24, 0.98),
    inset 0 1px 0 rgba(201, 214, 232, 0.08);
  transition: padding 0.26s ease, border-color 0.26s ease, background-color 0.26s ease, box-shadow 0.26s ease;
}

.site-header[data-scrolled="true"] .header-shell {
  padding-block: 5px;
  border-color: rgba(59, 227, 208, 0.55);
  background: rgba(6, 10, 24, 0.93);
  box-shadow:
    0 16px 34px -24px rgba(6, 10, 24, 1),
    inset 0 1px 0 rgba(59, 227, 208, 0.14);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  min-width: 0;
  color: var(--white);
  text-decoration: none;
}
.brand-mark {
  display: grid;
  place-items: center;
  flex: none;
  width: 34px;
  height: 34px;
  color: var(--cyan);
  border: 2px solid rgba(59, 227, 208, 0.6);
  border-radius: 10px;
  background:
    radial-gradient(circle at 30% 24%, rgba(59, 227, 208, 0.34), transparent 68%),
    var(--ink-800);
  transition: border-color 0.2s ease, color 0.2s ease;
}
.brand-mark svg { width: 20px; height: 20px; }
.brand:hover .brand-mark { border-color: var(--gold); color: var(--gold); }

.brand-text { display: flex; flex-direction: column; min-width: 0; line-height: 1.08; }
.brand-name {
  font-size: 1.02rem;
  font-weight: 900;
  letter-spacing: 0.02em;
  white-space: nowrap;
}
.brand-tagline {
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.14em;
  color: var(--mist);
  white-space: nowrap;
}

/* 移动端栏目按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  margin-left: auto;
  padding: 9px 15px;
  border: 2px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: rgba(59, 227, 208, 0.09);
  color: var(--white);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}
.nav-toggle:hover { border-color: var(--cyan); background: rgba(59, 227, 208, 0.16); }
.nav-toggle-bars { display: grid; gap: 4px; width: 16px; }
.nav-toggle-bars span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
  transition: transform 0.22s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:first-child { transform: translateY(3px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:last-child { transform: translateY(-3px) rotate(-45deg); }
.nav-toggle-label { white-space: nowrap; }

/* 导航主体 */
.primary-nav {
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.4vw, 18px);
  margin-left: auto;
}

.nav-list { display: flex; align-items: center; gap: 2px; }

.nav-list a {
  position: relative;
  display: inline-block;
  padding: 8px 10px;
  border-radius: var(--radius-pill);
  font-size: 0.86rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--silver);
  text-decoration: none;
  transition: color 0.18s ease, background-color 0.18s ease;
}
.nav-list a::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 4px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.22s ease, background-color 0.18s ease;
}
.nav-list a:hover { color: var(--white); background: rgba(59, 227, 208, 0.08); }
.nav-list a:hover::after { transform: scaleX(1); }

.nav-list a[aria-current="page"] {
  color: var(--cyan);
  background: rgba(59, 227, 208, 0.12);
}
.nav-list a[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--gold);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: 10px;
  border-left: 1px solid var(--line);
}

/* 阅读进度轨道 */
.scroll-progress {
  max-width: var(--wrap);
  margin: 8px auto 0;
  height: 3px;
  border-radius: 3px;
  background: rgba(124, 144, 174, 0.16);
  overflow: hidden;
  pointer-events: none;
}
.scroll-progress span {
  display: block;
  width: 0;
  height: 100%;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--cyan-deep), var(--cyan) 62%, var(--gold));
  transition: width 0.12s linear;
}

/* ---------- 6. 地平线页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 10vw, 140px);
  padding: clamp(44px, 6vw, 84px) 0 0;
  border-top: 2px solid var(--line);
  background: linear-gradient(180deg, rgba(15, 26, 48, 0) 0%, rgba(15, 26, 48, 0.92) 16%, #070D1C 100%);
  overflow: hidden;
}

.footer-orbit {
  position: absolute;
  left: -12%;
  right: -12%;
  bottom: -260px;
  height: 380px;
  border-radius: 50%;
  border: 2px solid rgba(59, 227, 208, 0.16);
  box-shadow: 0 0 160px 30px rgba(59, 227, 208, 0.1);
  pointer-events: none;
}

.footer-wrap {
  position: relative;
  z-index: 1;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1.5fr) minmax(0, 1.1fr);
  gap: clamp(28px, 4vw, 56px);
}

.footer-brand-link { display: inline-flex; }
.footer-line {
  margin-top: 16px;
  max-width: 34ch;
  font-size: 0.92rem;
  line-height: 1.78;
  color: var(--silver);
}
.footer-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.footer-nav {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}

.footer-col-title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--mist);
  text-transform: uppercase;
}

.footer-list { display: grid; gap: 10px; }
.footer-list a {
  display: inline-block;
  padding: 2px 0;
  font-size: 0.92rem;
  color: var(--silver);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}
.footer-list a:hover { color: var(--cyan); border-bottom-color: var(--line-strong); }

.contact-list { display: grid; gap: 12px; }
.contact-item {
  display: grid;
  gap: 2px;
  padding-bottom: 11px;
  border-bottom: 1px dashed rgba(124, 144, 174, 0.22);
}
.contact-item:last-child { border-bottom: 0; padding-bottom: 0; }
.contact-key {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.16em;
  color: var(--mist);
}
.contact-value {
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--silver);
  word-break: break-word;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  margin-top: clamp(32px, 4vw, 52px);
  padding: 20px 0 28px;
  border-top: 1px solid var(--line-soft);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 10px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.04em;
  color: var(--mist);
}
.legal-dot { color: rgba(124, 144, 174, 0.55); }

.footer-legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
}
.footer-legal-links a {
  font-size: 0.8rem;
  color: var(--silver);
  text-decoration: none;
  padding-bottom: 1px;
  border-bottom: 1px solid rgba(124, 144, 174, 0.3);
  transition: color 0.18s ease, border-color 0.18s ease;
}
.footer-legal-links a:hover { color: var(--cyan); border-bottom-color: var(--cyan); }

/* 返回顶部 */
.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 28px);
  bottom: clamp(14px, 3vw, 28px);
  z-index: 80;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border: 2px solid var(--line-strong);
  border-radius: 50%;
  background: rgba(15, 26, 48, 0.92);
  color: var(--cyan);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  box-shadow: 0 18px 30px -18px rgba(6, 10, 24, 1);
  transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s, border-color 0.18s ease, color 0.18s ease;
}
.to-top[data-visible="true"] { opacity: 1; visibility: visible; transform: translateY(0); }
.to-top:hover { border-color: var(--gold); color: var(--gold); }

/* ---------- 7. 通用容器与排版 ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section-head { display: grid; gap: 14px; margin-bottom: clamp(24px, 3vw, 40px); }

.lede {
  max-width: 62ch;
  font-size: clamp(1rem, 1.4vw, 1.12rem);
  line-height: 1.75;
  color: var(--silver);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--cyan);
  text-transform: uppercase;
}
.eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
}

.chapter-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2.4rem, 5vw, 4rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: transparent;
  -webkit-text-stroke: 1.5px rgba(59, 227, 208, 0.42);
}

.breath-band {
  padding: clamp(48px, 9vw, 120px) var(--gutter);
  border-block: 2px solid rgba(59, 227, 208, 0.14);
  background: linear-gradient(90deg, rgba(20, 52, 58, 0.55), rgba(6, 10, 24, 0) 62%);
}

/* ---------- 8. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border: 2px solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-sans);
  font-size: 0.86rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.16s ease, background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease;
}

.btn-gold {
  background: var(--gold);
  color: var(--gold-ink);
  border-color: var(--gold);
  box-shadow: 0 4px 0 rgba(6, 10, 24, 0.9);
}
.btn-gold:hover { background: #FFCA6B; transform: translateY(-1px); }
.btn-gold:active { transform: translateY(2px); box-shadow: 0 2px 0 rgba(6, 10, 24, 0.9); }

.btn-outline {
  background: transparent;
  color: var(--cyan);
  border-color: var(--line-strong);
}
.btn-outline:hover {
  background: rgba(59, 227, 208, 0.12);
  border-color: var(--cyan);
  color: var(--white);
}

.btn-ghost {
  background: transparent;
  color: var(--silver);
  border-color: rgba(124, 144, 174, 0.4);
}
.btn-ghost:hover { color: var(--white); border-color: var(--silver); background: rgba(201, 214, 232, 0.08); }

.btn-sm { padding: 8px 15px; font-size: 0.78rem; letter-spacing: 0.05em; }

/* ---------- 9. 卡片 / 标签 / 数据条带 ---------- */
.card {
  position: relative;
  padding: clamp(20px, 3vw, 30px);
  border: 2px solid var(--line);
  border-radius: var(--radius-md);
  background: linear-gradient(160deg, rgba(15, 26, 48, 0.96), rgba(6, 10, 24, 0.96));
  box-shadow: var(--shadow-hard);
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.card:hover { border-color: var(--line-strong); transform: translate(-2px, -2px); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: rgba(59, 227, 208, 0.08);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  white-space: nowrap;
}
.tag--gold {
  color: var(--gold);
  border-color: rgba(246, 185, 74, 0.42);
  background: rgba(246, 185, 74, 0.1);
}

.data-band {
  display: flex;
  flex-wrap: wrap;
  gap: 1px;
  border: 2px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--line);
  overflow: hidden;
}
.data-band-item {
  flex: 1 1 180px;
  display: grid;
  gap: 4px;
  padding: 18px 20px;
  background: var(--ink-700);
}
.data-band-num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--cyan);
}
.data-band-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  color: var(--mist);
}

/* ---------- 10. 面包屑 ---------- */
.breadcrumb {
  max-width: var(--wrap);
  margin: clamp(20px, 3vw, 34px) auto 0;
  padding-inline: var(--gutter);
}
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--mist);
}
.breadcrumb-list li { display: flex; align-items: center; gap: 8px; }
.breadcrumb-list li:not(:last-child)::after {
  content: "/";
  color: rgba(124, 144, 174, 0.5);
}
.breadcrumb-list a { color: var(--silver); text-decoration: none; }
.breadcrumb-list a:hover { color: var(--cyan); }
.breadcrumb-current { color: var(--white); }

/* ---------- 11. 图片容器基础规则（页面阶段放图） ---------- */
.media-frame {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border: 2px solid var(--line);
  border-radius: var(--radius-md);
  background:
    radial-gradient(circle at 28% 18%, rgba(59, 227, 208, 0.16), transparent 62%),
    var(--ink-800);
  box-shadow: var(--shadow-hard);
}
.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(59, 227, 208, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(59, 227, 208, 0.1) 1px, transparent 1px);
  background-size: 32px 32px;
  opacity: 0.7;
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px rgba(6, 10, 24, 0.55);
}
.media-frame img {
  position: relative;
  z-index: 1;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--screen { aspect-ratio: 9 / 19; max-width: 320px; margin-inline: auto; }

.media-caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

/* ---------- 12. 章节跟随目录 ---------- */
.chapter-rail {
  position: sticky;
  top: 104px;
  display: grid;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
}
.chapter-rail a {
  display: block;
  padding: 7px 10px;
  color: var(--mist);
  text-decoration: none;
  border-left: 2px solid rgba(124, 144, 174, 0.25);
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}
.chapter-rail a:hover { color: var(--silver); background: rgba(201, 214, 232, 0.05); }
.chapter-rail a[aria-current] {
  color: var(--cyan);
  border-left-color: var(--cyan);
  background: rgba(59, 227, 208, 0.08);
}

/* ---------- 13. 进入视口的显现 ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(12px);
}
.js .reveal.is-revealed {
  opacity: 1;
  transform: none;
  transition: opacity 0.5s ease, transform 0.5s ease;
}

/* ---------- 14. 响应式 ---------- */
@media (max-width: 1080px) {
  .brand-tagline { display: none; }
  .nav-list a { padding: 8px; font-size: 0.82rem; }
  .nav-actions .btn-ghost { display: none; }
  .footer-top { grid-template-columns: minmax(0, 1.2fr) minmax(0, 1.4fr); }
  .footer-contact { grid-column: 1 / -1; }
  .contact-list { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px 28px; }
  .chapter-rail { position: static; top: auto; }
}

@media (max-width: 900px) {
  html { scroll-padding-top: 96px; }

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

  .primary-nav {
    position: fixed;
    top: calc(env(safe-area-inset-top, 0px) + 78px);
    left: 12px;
    right: 12px;
    z-index: 95;
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
    max-height: calc(100vh - 104px);
    overflow-y: auto;
    padding: 14px;
    margin-left: 0;
    border: 2px solid var(--line-strong);
    border-radius: 24px;
    background: rgba(8, 13, 27, 0.97);
    -webkit-backdrop-filter: blur(18px);
    backdrop-filter: blur(18px);
    box-shadow: 0 34px 64px -24px rgba(0, 0, 0, 0.95);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-10px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
  }
  .primary-nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: none;
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 4px; }
  .nav-list a {
    display: block;
    padding: 13px 15px;
    font-size: 1rem;
    border: 1px solid transparent;
    border-radius: 14px;
  }
  .nav-list a::after { display: none; }
  .nav-list a[aria-current="page"] { border-color: var(--line-strong); }

  .nav-actions {
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    padding: 14px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }
  .nav-actions .btn { width: 100%; }
  .nav-actions .btn-ghost { display: inline-flex; }

  .site-header { padding-bottom: 6px; }
  .scroll-progress { margin-top: 6px; }

  .footer-top { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-contact { grid-column: auto; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 560px) {
  .brand-name { font-size: 0.96rem; }
  .brand-mark { width: 30px; height: 30px; border-radius: 9px; }
  .brand-mark svg { width: 17px; height: 17px; }
  .nav-toggle-label { font-size: 0.74rem; }

  .contact-list { grid-template-columns: minmax(0, 1fr); }
  .footer-nav { grid-template-columns: minmax(0, 1fr); gap: 26px; }
  .footer-actions .btn { flex: 1 1 auto; }
  .to-top { width: 42px; height: 42px; }
}

/* ---------- 15. 减少动效 ---------- */
@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;
    scroll-behavior: auto !important;
  }

  .js .reveal { opacity: 1; transform: none; }

  .card:hover { transform: none; }
  .btn-gold:hover { transform: none; }
  .to-top { transform: none; }
  .scroll-progress span { transition: none; }
}