/* ==========================================================================
   乐鱼体育 · 共享样式表 /assets/site.css
   纵向叙事长卷 · 运动控制台视觉系统
   ========================================================================== */

/* ------------------------------------------------------------------ 1. 变量 */
:root {
  /* 品牌色 */
  --deep-900: #061826;
  --deep-800: #0A2137;
  --deep-700: #0D2A42;
  --deep-500: #164A6E;
  --coral-500: #FF6B4A;
  --coral-300: #FF9B7A;
  --cyan-400: #2DE1C2;
  --gold-400: #F5B942;
  --light-50: #F5F7FA;
  --light-200: #E3E9F0;
  --ink-900: #0B1219;
  --ink-700: #29394A;
  --ink-500: #5C6E80;

  /* 文字 */
  --tx-hi: #EDF4F9;
  --tx-mi: rgba(237, 244, 249, .72);
  --tx-lo: rgba(237, 244, 249, .5);

  /* 结构 */
  --header-h: 78px;
  --wrap: 1180px;
  --wrap-narrow: 760px;
  --line: rgba(45, 225, 194, .16);
  --line-soft: rgba(22, 74, 110, .55);
  --radius-s: 6px;
  --radius-m: 16px;
  --radius-l: 28px;

  /* 字体 */
  --font-sans: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-serif: "Noto Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --font-mono: "IBM Plex Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* 字号阶梯 */
  --fs-12: .75rem;
  --fs-14: .875rem;
  --fs-16: 1rem;
  --fs-18: 1.125rem;
  --fs-22: 1.375rem;
  --fs-28: 1.75rem;
  --fs-36: clamp(1.875rem, 4.4vw, 2.375rem);
  --fs-48: clamp(2.25rem, 6vw, 3rem);
  --fs-64: clamp(2.75rem, 8vw, 4rem);
  --fs-80: clamp(3rem, 10vw, 5rem);

  --ease: cubic-bezier(.2, .7, .3, 1);
  --speed: .28s;
}

/* ------------------------------------------------------------------ 2. 重置 */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--fs-16);
  line-height: 1.75;
  color: var(--tx-hi);
  background-color: var(--deep-900);
  background-image:
    radial-gradient(900px 520px at 82% -8%, rgba(45, 225, 194, .10), transparent 62%),
    radial-gradient(760px 480px at 4% 4%, rgba(255, 107, 74, .09), transparent 60%);
  background-repeat: no-repeat;
  overflow-x: hidden;
}

body.nav-open { overflow: hidden; }

h1, h2, h3, h4 {
  margin: 0;
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -.015em;
}

p { margin: 0; }

ul, ol { margin: 0; padding: 0; }

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--speed) var(--ease), border-color var(--speed) var(--ease);
}

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

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

strong, b { font-weight: 800; }

code, kbd, samp, pre { font-family: var(--font-mono); }

::selection {
  background: var(--coral-500);
  color: #fff;
}

:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: 3px;
  border-radius: 3px;
}

#main-content { scroll-margin-top: calc(var(--header-h) + 16px); }

/* -------------------------------------------------------------- 3. 跳至内容 */
.skip-link {
  position: fixed;
  top: 0;
  left: 20px;
  z-index: 120;
  padding: 12px 22px;
  font-size: var(--fs-14);
  font-weight: 700;
  color: var(--deep-900);
  background: var(--cyan-400);
  border-radius: 0 0 var(--radius-m) var(--radius-m);
  transform: translateY(-140%);
  transition: transform var(--speed) var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
  outline-offset: -4px;
}

/* --------------------------------------------------------------- 4. 通用容器 */
.wrap {
  width: min(100% - 40px, var(--wrap));
  margin-inline: auto;
}

.site-main { position: relative; z-index: 1; }

.has-header-offset { padding-top: var(--header-h); }

.section {
  position: relative;
  padding: clamp(56px, 8vw, 116px) 0;
}

.section--deep { background: var(--deep-900); color: var(--tx-hi); }

.section--panel {
  background: linear-gradient(180deg, var(--deep-800), var(--deep-900));
  color: var(--tx-hi);
}

.section--light {
  background: var(--light-50);
  color: var(--ink-900);
}

.section--light .eyebrow { color: var(--deep-500); }
.section--light .eyebrow::before { background: var(--deep-500); }
.section--light .chapter-line { background: linear-gradient(90deg, rgba(22, 74, 110, .5), transparent); }
.section--light .chapter-title { color: var(--ink-900); }

/* --------------------------------------------------------------- 5. 章节结构 */
.chapter {
  display: flex;
  align-items: baseline;
  gap: 18px;
  margin-bottom: clamp(26px, 4vw, 42px);
}

.chapter-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--coral-500);
}

.chapter-title {
  margin: 0;
  font-size: var(--fs-36);
  font-weight: 900;
}

.chapter-line {
  flex: 1;
  height: 1px;
  margin-bottom: 10px;
  background: linear-gradient(90deg, rgba(45, 225, 194, .55), transparent);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--cyan-400);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: currentColor;
  opacity: .8;
}

.lead {
  font-size: var(--fs-18);
  line-height: 1.85;
  color: var(--tx-mi);
  max-width: 62ch;
}

.section--light .lead { color: var(--ink-700); }

/* ------------------------------------------------------------------ 6. 网格 */
.grid { display: grid; gap: clamp(16px, 2.4vw, 26px); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(238px, 1fr)); }

/* ------------------------------------------------------------------ 7. 卡片 */
.panel {
  position: relative;
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--deep-700);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  transition: transform var(--speed) var(--ease),
              border-color var(--speed) var(--ease),
              background-color var(--speed) var(--ease);
}

.panel:hover,
.panel:focus-within {
  transform: translateY(-4px);
  border-color: rgba(45, 225, 194, .48);
  background: var(--deep-800);
}

.panel--light {
  background: #fff;
  border-color: var(--light-200);
  color: var(--ink-900);
}

.panel--light:hover { background: #fff; border-color: var(--deep-500); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 600;
  letter-spacing: .06em;
  color: var(--cyan-400);
  background: rgba(45, 225, 194, .08);
  border: 1px solid rgba(45, 225, 194, .3);
  border-radius: 999px;
}

.section--light .tag {
  color: var(--deep-500);
  background: rgba(22, 74, 110, .06);
  border-color: rgba(22, 74, 110, .28);
}

.stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-48);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--cyan-400);
}

.section--light .stat-num { color: var(--deep-500); }

/* ------------------------------------------------------------------ 8. 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .02em;
  line-height: 1.2;
  text-align: center;
  color: #fff;
  background: var(--deep-500);
  border: 1px solid transparent;
  border-radius: 999px;
  cursor: pointer;
  transition: transform var(--speed) var(--ease),
              box-shadow var(--speed) var(--ease),
              background-color var(--speed) var(--ease),
              color var(--speed) var(--ease),
              border-color var(--speed) var(--ease);
}

.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  color: #fff;
  background: var(--coral-500);
  box-shadow: 0 10px 26px -16px rgba(255, 107, 74, .95);
}

.btn--primary:hover {
  background: var(--coral-300);
  box-shadow: 0 18px 34px -18px rgba(255, 107, 74, .95);
}

.btn--ghost {
  color: var(--tx-hi);
  background: transparent;
  border-color: rgba(45, 225, 194, .42);
}

.btn--ghost:hover {
  color: var(--cyan-400);
  border-color: var(--cyan-400);
  background: rgba(45, 225, 194, .08);
}

.btn--sm {
  padding: 9px 18px;
  font-size: var(--fs-14);
}

/* ------------------------------------------------------------------ 9. 页头 */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 90;
  background: rgba(6, 24, 38, .74);
  border-bottom: 1px solid var(--line);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  transition: background-color var(--speed) var(--ease),
              border-color var(--speed) var(--ease),
              box-shadow var(--speed) var(--ease);
}

.site-header.is-solid {
  background: var(--deep-900);
  border-bottom-color: rgba(45, 225, 194, .34);
  box-shadow: 0 22px 46px -34px rgba(0, 0, 0, .95);
}

.header-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: rgba(22, 74, 110, .5);
  overflow: hidden;
  pointer-events: none;
}

.header-progress-bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan-400), var(--coral-500));
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  width: min(100% - 40px, var(--wrap));
  height: var(--header-h);
  margin-inline: auto;
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: none;
}

.brand-mark {
  display: inline-flex;
  align-items: flex-end;
  gap: 3px;
  width: 22px;
  height: 24px;
}

.brand-mark i {
  display: block;
  width: 4px;
  border-radius: 2px;
  background: var(--cyan-400);
  transition: height var(--speed) var(--ease);
}

.brand-mark i:nth-child(1) { height: 10px; background: var(--coral-500); }
.brand-mark i:nth-child(2) { height: 17px; background: var(--cyan-400); }
.brand-mark i:nth-child(3) { height: 24px; background: var(--gold-400); }

.brand:hover .brand-mark i:nth-child(1) { height: 14px; }
.brand:hover .brand-mark i:nth-child(2) { height: 21px; }

.brand-copy {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.brand-name {
  font-size: 17px;
  font-weight: 900;
  letter-spacing: .01em;
  color: #fff;
  line-height: 1.2;
}

.brand-line {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--tx-lo);
  line-height: 1.3;
}

/* 主导航 */
.primary-nav {
  display: flex;
  align-items: center;
  gap: 22px;
  margin-left: auto;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  list-style: none;
  counter-reset: nv;
}

.nav-item {
  counter-increment: nv;
  position: relative;
}

.nav-link {
  position: relative;
  display: inline-block;
  padding: 10px 13px;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--tx-mi);
  border-radius: var(--radius-s);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 13px;
  right: 13px;
  bottom: 5px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan-400);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--speed) var(--ease), background-color var(--speed) var(--ease);
}

.nav-link:hover,
.nav-link:focus-visible {
  color: #fff;
  background: rgba(45, 225, 194, .07);
}

.nav-link:hover::after,
.nav-link:focus-visible::after { transform: scaleX(1); }

.nav-link[aria-current="page"] {
  color: #fff;
}

.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--coral-500);
}

/* 页头右侧 */
.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: none;
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  height: 42px;
  padding: 0 15px;
  color: var(--tx-hi);
  background: rgba(13, 42, 66, .85);
  border: 1px solid rgba(45, 225, 194, .34);
  border-radius: 999px;
  cursor: pointer;
  transition: border-color var(--speed) var(--ease), color var(--speed) var(--ease);
}

.nav-toggle:hover { border-color: var(--cyan-400); color: #fff; }

.nav-toggle-text {
  font-size: var(--fs-14);
  font-weight: 700;
  letter-spacing: .04em;
}

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

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan-400);
  transition: transform var(--speed) var(--ease), top var(--speed) var(--ease);
}

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

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

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

.nav-foot { display: none; }

.status-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
  color: var(--tx-mi);
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan-400);
  animation: leyu-pulse 2.4s var(--ease) infinite;
}

@keyframes leyu-pulse {
  0%   { box-shadow: 0 0 0 0 rgba(45, 225, 194, .55); }
  70%  { box-shadow: 0 0 0 9px rgba(45, 225, 194, 0); }
  100% { box-shadow: 0 0 0 0 rgba(45, 225, 194, 0); }
}

/* ------------------------------------------------------------- 10. 移动导航 */
@media (max-width: 900px) {
  :root { --header-h: 66px; }

  .header-inner { gap: 12px; }

  .brand-line { display: none; }

  .header-actions { margin-left: auto; }

  .primary-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin: 0;
    padding: 6px 20px 30px;
    background: var(--deep-900);
    border-bottom: 1px solid rgba(45, 225, 194, .28);
    box-shadow: 0 34px 60px -34px rgba(0, 0, 0, .95);
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    overscroll-behavior: contain;
  }

  .site-header[data-open="true"] .primary-nav { display: flex; }
  .site-header[data-open="true"] { background: var(--deep-900); }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-item {
    display: grid;
    grid-template-columns: 42px 1fr;
    align-items: center;
    border-bottom: 1px solid var(--line-soft);
  }

  .nav-item::before {
    content: "0" counter(nv);
    font-family: var(--font-mono);
    font-size: var(--fs-12);
    font-weight: 700;
    color: var(--cyan-400);
    opacity: .6;
    justify-self: start;
  }

  .nav-link {
    display: block;
    padding: 16px 0;
    font-size: 17px;
    color: var(--tx-hi);
    border-radius: 0;
  }

  .nav-link::after { display: none; }

  .nav-link[aria-current="page"] { color: var(--coral-500); }
  .nav-link[aria-current="page"]::after { display: none; }

  .nav-foot {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 16px;
    padding-top: 24px;
  }

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

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

@media (max-width: 560px) {
  .header-cta { display: none; }
  .brand-name { font-size: 16px; }
}

/* ------------------------------------------------------------------ 11. 页脚 */
.site-footer {
  position: relative;
  color: var(--tx-mi);
  background: linear-gradient(180deg, var(--deep-900) 0%, #04121C 100%);
  border-top: 1px solid var(--line);
}

.footer-rail {
  height: 3px;
  width: 100%;
  background: linear-gradient(90deg,
    var(--coral-500) 0 12%,
    var(--gold-400) 12% 22%,
    var(--cyan-400) 22% 34%,
    rgba(22, 74, 110, .9) 34% 100%);
}

.footer-inner {
  width: min(100% - 40px, var(--wrap));
  margin-inline: auto;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.6fr .85fr .85fr 1.35fr;
  gap: clamp(24px, 4vw, 48px);
  padding: clamp(40px, 6vw, 68px) 0 clamp(32px, 5vw, 52px);
}

.footer-brand .brand-name { font-size: 20px; }

.footer-note {
  max-width: 34ch;
  margin: 18px 0 14px;
  font-size: var(--fs-14);
  line-height: 1.85;
  color: var(--tx-lo);
}

.footer-domain {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: .04em;
  color: var(--cyan-400);
}

.footer-title {
  position: relative;
  margin: 0 0 20px;
  padding-bottom: 12px;
  font-size: var(--fs-14);
  font-weight: 800;
  letter-spacing: .16em;
  color: #fff;
}

.footer-title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 26px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan-400);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
  list-style: none;
}

.footer-links a {
  display: inline-block;
  font-size: 15px;
  color: var(--tx-mi);
}

.footer-links a:hover {
  color: var(--cyan-400);
  transform: translateX(4px);
}

.contact-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  list-style: none;
}

.contact-item {
  display: grid;
  grid-template-columns: 66px 1fr;
  gap: 12px;
  align-items: start;
}

.contact-key {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .1em;
  color: var(--tx-lo);
  padding-top: 2px;
}

.contact-val {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  line-height: 1.7;
  color: var(--tx-hi);
  word-break: break-word;
}

.contact-val--text {
  font-family: var(--font-sans);
  color: var(--tx-mi);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 28px;
  padding: 22px 0 32px;
  border-top: 1px solid var(--line-soft);
  font-size: var(--fs-12);
  color: var(--tx-lo);
}

.footer-copy { font-family: var(--font-mono); letter-spacing: .04em; }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  font-family: var(--font-mono);
  letter-spacing: .04em;
}

@media (max-width: 900px) {
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-contact { grid-column: 1 / -1; }
}

@media (max-width: 560px) {
  .footer-top { grid-template-columns: 1fr; gap: 34px; }
  .contact-item { grid-template-columns: 1fr; gap: 2px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

/* ------------------------------------------------------------- 12. 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--tx-lo);
}

.breadcrumbs li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumbs li + li::before {
  content: "/";
  color: rgba(45, 225, 194, .5);
}

.breadcrumbs a:hover { color: var(--cyan-400); }

.section--light .breadcrumbs { color: var(--ink-500); }

/* ------------------------------------------------------------- 13. 正文排版 */
.prose {
  max-width: 74ch;
  font-size: 17px;
  line-height: 1.85;
  color: inherit;
}

.prose > * + * { margin-top: 1.15em; }

.prose h2 {
  font-size: var(--fs-28);
  margin-top: 2em;
}

.prose h3 {
  font-size: var(--fs-22);
  margin-top: 1.7em;
}

.prose ul,
.prose ol {
  padding-left: 1.35em;
}

.prose li + li { margin-top: .45em; }

.prose li::marker { color: var(--coral-500); }

.prose a {
  color: var(--coral-500);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

.prose a:hover { color: var(--coral-300); }

.prose blockquote {
  margin-inline: 0;
  padding: 4px 0 4px 22px;
  border-left: 2px solid var(--cyan-400);
  font-family: var(--font-serif);
  font-size: var(--fs-18);
  color: var(--tx-mi);
}

.section--light .prose blockquote { color: var(--ink-700); }

.prose hr {
  border: 0;
  height: 1px;
  background: var(--line-soft);
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--fs-14);
}

.prose th,
.prose td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line-soft);
}

.section--light .prose th,
.section--light .prose td { border-bottom-color: var(--light-200); }

.prose th {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
  color: var(--cyan-400);
}

.section--light .prose th { color: var(--deep-500); }

/* --------------------------------------------------------- 14. 图片容器基础 */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--deep-700), var(--deep-900));
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
}

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

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 52%, rgba(6, 24, 38, .74) 100%);
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--portrait { aspect-ratio: 3 / 4; }

.media-frame--empty::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(45, 225, 194, .12) 1px, transparent 1px),
    linear-gradient(90deg, rgba(45, 225, 194, .12) 1px, transparent 1px);
  background-size: 28px 28px;
}

.media-caption {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .04em;
  color: var(--tx-lo);
}

.section--light .media-caption { color: var(--ink-500); }

/* --------------------------------------------------------------- 15. 显现 */
[data-reveal] {
  transition: opacity .6s var(--ease), transform .6s var(--ease);
}

html.is-reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
}

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

/* ----------------------------------------------------- 16. 降低动态效果偏好 */
@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;
  }

  html.is-reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .btn:hover,
  .panel:hover,
  .panel:focus-within,
  .footer-links a:hover { transform: none; }
}