/* =============================================================
   米兰体育CN · 共享样式表  /assets/site.css
   基调：主场黑 × 米兰红锚点 × 海河蓝数据 × 霓虹金刻度
   ============================================================= */

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

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

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

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

ul[class], ol[class] { list-style: none; padding: 0; }

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

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

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

button { background: none; border: 0; cursor: pointer; }

table { border-collapse: collapse; width: 100%; }

:focus-visible {
  outline: 2px solid #E8B33C;
  outline-offset: 3px;
  border-radius: 6px;
}

::selection { background: #C8102E; color: #FFFFFF; }

/* ---------- 2. 变量 ---------- */
:root {
  --ink: #0B0B0F;
  --char: #16171C;
  --red: #C8102E;
  --red-deep: #8A0A1F;
  --orange: #FF6A1A;
  --hai: #1D6FB8;
  --hai-light: #4C9BE0;
  --gold: #E8B33C;
  --ice: #F5F6F8;
  --paper: #FFFFFF;
  --gray-idx: #8A8F99;
  --hair: #D8DBE1;
  --night-blue: #0E3A63;
  --ink-soft: #565B64;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", "Courier New", "PingFang SC", monospace;

  --shell: 1360px;
  --gutter: clamp(1.1rem, 4vw, 3.5rem);
  --header-h: 74px;

  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 22px;
  --r-organic: 26px 6px 26px 6px;

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

/* ---------- 3. 中文排版基底 ---------- */
body {
  background: var(--ink);
  color: var(--ice);
  font-family: var(--font-sans);
  font-size: clamp(16px, 0.35vw + 15.2px, 17.5px);
  line-height: 1.75;
  font-weight: 400;
  letter-spacing: .01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5 {
  line-height: 1.22;
  font-weight: 800;
  letter-spacing: -.004em;
}

p { text-wrap: pretty; }

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

.visually-hidden {
  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;
}

.skip-link {
  position: fixed;
  top: -120px;
  left: var(--gutter);
  z-index: 300;
  background: var(--orange);
  color: var(--ink);
  font-weight: 800;
  font-size: .92rem;
  padding: .7rem 1.15rem;
  border-radius: var(--r-sm);
  transition: top .22s var(--ease);
}
.skip-link:focus { top: .8rem; }

/* ---------- 4. 布局骨架 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  position: relative;
  padding-block: clamp(3.5rem, 9vw, 8rem);
}

.section--dark { background: var(--ink); color: var(--ice); }
.section--panel { background: var(--char); color: var(--ice); }

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

.section--night {
  background:
    radial-gradient(120% 90% at 12% 0%, rgba(29, 111, 184, .38), transparent 62%),
    linear-gradient(180deg, var(--night-blue), var(--ink) 78%);
  color: var(--ice);
}

.grid { display: grid; gap: clamp(1rem, 2.4vw, 2rem); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

@media (max-width: 900px) {
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
  .grid--2, .grid--3 { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- 5. 章节抬头 ---------- */
.section-head {
  display: grid;
  gap: .85rem;
  max-width: 64ch;
  margin-bottom: clamp(1.75rem, 4vw, 3rem);
}

.section-head__eyebrow {
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .3em;
  text-transform: uppercase;
  color: var(--red);
}

.section-head__title {
  font-size: clamp(1.75rem, 3.6vw, 3rem);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -.015em;
}

.section-head__lead {
  color: var(--gray-idx);
  font-size: 1.01rem;
  line-height: 1.8;
}

.section--light .section-head__eyebrow { color: var(--red-deep); }
.section--light .section-head__lead { color: var(--ink-soft); }

/* 细字重超大标题 —— 封面与章节大数字 */
.display {
  font-weight: 200;
  font-size: clamp(3.5rem, 9vw, 8rem);
  line-height: .95;
  letter-spacing: -.035em;
}

/* ---------- 6. 正文 ---------- */
.prose {
  max-width: 68ch;
  font-size: 1.02rem;
  line-height: 1.85;
  color: inherit;
}
.prose p + p { margin-top: 1.05em; }
.prose h2 { font-size: clamp(1.3rem, 2.2vw, 1.75rem); margin-top: 1.9em; margin-bottom: .55em; }
.prose h3 { font-size: clamp(1.1rem, 1.7vw, 1.3rem); margin-top: 1.5em; margin-bottom: .45em; }
.prose ul, .prose ol { padding-left: 1.3rem; margin-block: .9em; }
.prose li + li { margin-top: .4em; }
.prose strong { font-weight: 800; color: var(--paper); }
.prose a { color: var(--hai-light); border-bottom: 1px solid rgba(76, 155, 224, .5); }
.prose a:hover { border-bottom-color: var(--hai-light); }

.section--light .prose { color: #3B4048; }
.section--light .prose strong { color: var(--ink); }
.section--light .prose a { color: var(--hai); border-bottom-color: rgba(29, 111, 184, .45); }

/* ---------- 7. 等宽数字与标签 ---------- */
.index-num {
  font-family: var(--font-mono);
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--gold);
  text-shadow: 0 0 14px rgba(232, 179, 60, .35);
}
.index-num--red {
  color: var(--red);
  text-shadow: 0 0 16px rgba(200, 16, 46, .45);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: .35em;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  padding: .32rem .7rem;
  border-radius: 999px;
  border: 1px solid rgba(245, 246, 248, .22);
  color: var(--ice);
  background: rgba(245, 246, 248, .05);
}
.section--light .tag {
  border-color: var(--hair);
  color: var(--ink-soft);
  background: rgba(11, 11, 15, .03);
}

/* ---------- 8. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .66rem 1.2rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: .9rem;
  font-weight: 700;
  letter-spacing: .02em;
  white-space: nowrap;
  transition: transform .22s var(--ease), background-color .22s var(--ease),
              color .22s var(--ease), border-color .22s var(--ease);
}

.btn--feedback {
  background: var(--orange);
  color: #0B0B0F;
  box-shadow: 0 8px 26px rgba(255, 106, 26, .26);
}
.btn--feedback:hover { background: #FF7F38; transform: translateY(-1px); }

.btn--ghost {
  border-color: rgba(245, 246, 248, .3);
  color: var(--ice);
}
.btn--ghost:hover { border-color: var(--gold); color: var(--gold); }

.btn--ink {
  background: var(--ink);
  color: var(--ice);
}
.btn--ink:hover { background: var(--red); }

.section--light .btn--ghost {
  border-color: rgba(11, 11, 15, .25);
  color: var(--ink);
}
.section--light .btn--ghost:hover { border-color: var(--red); color: var(--red); }

/* ---------- 9. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background: rgba(11, 11, 15, .9);
  color: var(--ice);
  border-bottom: 1px solid rgba(245, 246, 248, .08);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  backdrop-filter: blur(14px) saturate(140%);
  transition: background-color .3s var(--ease), border-color .3s var(--ease);
}

.site-header[data-condensed] {
  background: rgba(11, 11, 15, .97);
  border-bottom-color: rgba(200, 16, 46, .55);
}

.header-shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(.7rem, 1.5vw, 1.15rem) var(--gutter);
  display: flex;
  align-items: center;
  gap: clamp(.6rem, 1.6vw, 1.6rem);
  transition: padding-block .3s var(--ease);
}

.site-header[data-condensed] .header-shell { padding-block: .5rem; }

/* 品牌 */
.brand-mark {
  display: flex;
  flex-direction: column;
  gap: .16rem;
  line-height: 1;
  flex: none;
}

.brand-mark__name {
  font-size: clamp(1.02rem, 1.4vw, 1.28rem);
  font-weight: 900;
  letter-spacing: .01em;
  color: var(--paper);
}

.brand-mark__cn {
  margin-left: .34em;
  font-family: var(--font-mono);
  font-size: .68em;
  letter-spacing: .16em;
  color: var(--red);
}

.brand-mark__city {
  font-family: var(--font-mono);
  font-size: .64rem;
  letter-spacing: .26em;
  color: var(--gray-idx);
}

/* 导航 */
.site-nav { margin-left: auto; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(.1rem, .8vw, .8rem);
}

.site-nav__item { display: flex; }

.site-nav__link {
  position: relative;
  display: inline-flex;
  padding: .5rem .6rem;
  font-size: clamp(.82rem, .95vw, .92rem);
  color: rgba(245, 246, 248, .76);
  border-radius: 999px;
  white-space: nowrap;
  transition: color .22s var(--ease);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: .6rem;
  right: .6rem;
  bottom: .22rem;
  height: 2px;
  background: var(--red);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .28s var(--ease), background-color .22s var(--ease);
}

.site-nav__link:hover { color: var(--paper); }
.site-nav__link:hover::after { transform: scaleX(1); }

.site-nav__link[aria-current="page"] {
  color: var(--paper);
  font-weight: 800;
}
.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--gold);
}

/* 头部行动区 */
.header-cta { display: flex; align-items: center; flex: none; }

/* 折叠按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: .5rem;
  padding: .5rem .7rem;
  border: 1px solid rgba(245, 246, 248, .22);
  border-radius: 999px;
  color: var(--ice);
  flex: none;
}

.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 18px;
}
.nav-toggle__bars i {
  display: block;
  height: 1.5px;
  background: currentColor;
  transition: transform .25s var(--ease), opacity .25s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(5.5px) 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(-5.5px) rotate(-45deg); }

.nav-toggle__label {
  font-size: .78rem;
  letter-spacing: .16em;
}

/* 左侧轮次轴 */
.round-rail {
  position: fixed;
  left: clamp(.5rem, 1.4vw, 1.4rem);
  top: 50%;
  transform: translateY(-50%);
  z-index: 110;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 13px;
  opacity: 0;
  pointer-events: none;
  transition: opacity .45s var(--ease);
}
.round-rail[data-visible] { opacity: 1; }

.round-rail__line {
  width: 1px;
  height: clamp(70px, 16vh, 150px);
  background: linear-gradient(180deg, rgba(200, 16, 46, 0), var(--red), rgba(200, 16, 46, 0));
}

.round-rail__tick {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: rgba(245, 246, 248, .26);
  transition: background-color .3s var(--ease), box-shadow .3s var(--ease), transform .3s var(--ease);
}
.round-rail__tick--on {
  background: var(--gold);
  transform: scale(1.5);
  box-shadow: 0 0 12px rgba(232, 179, 60, .85);
}

@media (max-width: 900px) {
  .round-rail { display: none; }
}

/* 移动端导航面板 */
@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-left: 0;
    background: rgba(11, 11, 15, .985);
    border-bottom: 2px solid var(--red);
    padding: .35rem var(--gutter) 1.4rem;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity .26s var(--ease), transform .26s var(--ease), visibility .26s linear;
  }

  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__item { border-bottom: 1px solid rgba(245, 246, 248, .08); }

  .site-nav__link {
    padding: .95rem .2rem;
    font-size: 1rem;
    border-radius: 0;
    width: 100%;
  }
  .site-nav__link::after {
    left: .2rem;
    right: auto;
    width: 26px;
    bottom: .72rem;
  }
}

@media (max-width: 560px) {
  .brand-mark__city { display: none; }
  .btn--feedback { padding: .58rem .95rem; font-size: .84rem; }
  .nav-toggle__label { display: none; }
}

/* ---------- 10. 页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  color: var(--ice);
  border-top: 1px solid rgba(245, 246, 248, .09);
}

.site-footer::before {
  content: "";
  position: absolute;
  left: -14%;
  bottom: -46%;
  width: min(58vw, 720px);
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 50%, rgba(200, 16, 46, .3), rgba(200, 16, 46, 0) 66%);
  pointer-events: none;
}

.site-footer::after {
  content: "";
  position: absolute;
  right: -10%;
  top: -34%;
  width: min(46vw, 560px);
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 50%, rgba(29, 111, 184, .28), rgba(29, 111, 184, 0) 68%);
  pointer-events: none;
}

.footer-shell,
.footer-base {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.footer-shell {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 2fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  padding-block: clamp(3rem, 7vw, 5.5rem) clamp(2rem, 4vw, 3.25rem);
}

.footer-brand { display: grid; gap: .75rem; align-content: start; }

.footer-brand__mark {
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  font-weight: 900;
  letter-spacing: -.01em;
  color: var(--paper);
  line-height: 1.1;
}

.footer-brand__cn {
  margin-left: .34em;
  font-family: var(--font-mono);
  font-size: .58em;
  letter-spacing: .18em;
  color: var(--red);
}

.footer-brand__intro {
  color: var(--gray-idx);
  font-size: .95rem;
  line-height: 1.8;
  max-width: 34ch;
}

.footer-brand__counter {
  font-size: .8rem;
  letter-spacing: .06em;
  color: var(--gray-idx);
}

.footer-nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.25rem, 3vw, 2.5rem);
}

.footer-nav__title {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .3em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 1rem;
}

.footer-nav__list { display: flex; flex-direction: column; gap: .62rem; }

.footer-nav__link {
  display: inline-block;
  font-size: .95rem;
  color: var(--gray-idx);
  transition: color .2s var(--ease), transform .2s var(--ease);
}
.footer-nav__link:hover {
  color: var(--ice);
  transform: translateX(3px);
}

.footer-base {
  padding-bottom: clamp(1.5rem, 4vw, 2.75rem);
}

.footer-contact {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem 2rem;
  padding-top: clamp(1.4rem, 3vw, 2rem);
  border-top: 1px solid rgba(245, 246, 248, .09);
  color: var(--gray-idx);
  font-size: .86rem;
  letter-spacing: .04em;
}

.footer-contact__item { display: inline-flex; }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: .5rem 1.5rem;
  margin-top: 1.15rem;
  padding-top: 1.15rem;
  border-top: 1px solid rgba(245, 246, 248, .06);
  font-size: .76rem;
  letter-spacing: .06em;
  color: rgba(138, 143, 153, .9);
}

.footer-legal__note { color: rgba(138, 143, 153, .72); }

@media (max-width: 900px) {
  .footer-shell { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 620px) {
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand__intro { max-width: none; }
}

/* ---------- 11. 卡片 ---------- */
.card {
  display: flex;
  flex-direction: column;
  gap: .8rem;
  padding: clamp(1.25rem, 2.4vw, 2rem);
  background: var(--char);
  border: 1px solid rgba(245, 246, 248, .08);
  border-radius: var(--r-lg);
  transition: transform .25s var(--ease), border-color .25s var(--ease);
}
.card:hover {
  transform: translateY(-3px);
  border-color: rgba(232, 179, 60, .45);
}

.card__meta {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold);
}

.card__title {
  font-size: clamp(1.1rem, 1.7vw, 1.35rem);
  font-weight: 800;
  line-height: 1.36;
}

.card__body {
  color: var(--gray-idx);
  font-size: .95rem;
  line-height: 1.8;
}

.section--light .card {
  background: var(--paper);
  border-color: var(--hair);
  color: var(--ink);
}
.section--light .card__meta { color: var(--red-deep); }
.section--light .card__body { color: var(--ink-soft); }
.section--light .card:hover { border-color: rgba(200, 16, 46, .45); }

/* ---------- 12. 技能树式步骤 ---------- */
.step-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: clamp(1.1rem, 2.2vw, 1.7rem);
  counter-reset: step;
}

.step {
  position: relative;
  padding-left: 3.7rem;
  counter-increment: step;
}

.step::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: .1rem;
  width: 2.5rem;
  height: 2.5rem;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: .76rem;
  font-weight: 700;
  color: var(--gold);
  border: 1px solid rgba(232, 179, 60, .42);
  border-radius: 50%;
  background: rgba(232, 179, 60, .06);
}

.step::after {
  content: "";
  position: absolute;
  left: 1.25rem;
  top: 3rem;
  bottom: -1.1rem;
  width: 1px;
  background: linear-gradient(180deg, rgba(232, 179, 60, .42), rgba(232, 179, 60, 0));
}

.step:last-child::after { display: none; }

.step__title {
  font-size: 1.05rem;
  font-weight: 800;
  margin-bottom: .3rem;
}

.step__text {
  color: var(--gray-idx);
  font-size: .95rem;
  line-height: 1.8;
}

.section--light .step::before {
  color: var(--red-deep);
  border-color: rgba(200, 16, 46, .35);
  background: rgba(200, 16, 46, .05);
}
.section--light .step::after {
  background: linear-gradient(180deg, rgba(200, 16, 46, .3), rgba(200, 16, 46, 0));
}
.section--light .step__text { color: var(--ink-soft); }

/* ---------- 13. 折叠展开 ---------- */
.disclosure {
  background: rgba(22, 23, 28, .72);
  border: 1px solid rgba(245, 246, 248, .1);
  border-radius: var(--r-md);
  overflow: hidden;
}
.disclosure + .disclosure { margin-top: .75rem; }

.disclosure__trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem clamp(1rem, 2vw, 1.5rem);
  text-align: left;
  font-weight: 700;
  font-size: 1rem;
  transition: color .2s var(--ease);
}
.disclosure__trigger:hover { color: var(--gold); }

.disclosure__icon {
  position: relative;
  flex: none;
  width: 1.5rem;
  height: 1.5rem;
  border: 1px solid rgba(245, 246, 248, .22);
  border-radius: 50%;
}
.disclosure__icon::before,
.disclosure__icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 10px;
  height: 1.5px;
  background: currentColor;
  transform: translate(-50%, -50%);
  transition: transform .26s var(--ease), opacity .26s var(--ease);
}
.disclosure__icon::after { transform: translate(-50%, -50%) rotate(90deg); }
.disclosure__trigger[aria-expanded="true"] .disclosure__icon::after {
  transform: translate(-50%, -50%) rotate(0deg);
  opacity: 0;
}

.disclosure__panel {
  padding: 0 clamp(1rem, 2vw, 1.5rem) 1.3rem;
  color: var(--gray-idx);
  font-size: .95rem;
  line-height: 1.8;
}
.disclosure__panel[hidden] { display: none; }

.section--light .disclosure {
  background: var(--paper);
  border-color: var(--hair);
}
.section--light .disclosure__icon { border-color: rgba(11, 11, 15, .22); }
.section--light .disclosure__panel { color: var(--ink-soft); }

/* ---------- 14. 面包屑 ---------- */
.breadcrumb {
  padding-block: clamp(.9rem, 2vw, 1.4rem);
  font-size: .78rem;
  letter-spacing: .08em;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  color: var(--gray-idx);
}

.breadcrumb__link {
  color: var(--gray-idx);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.breadcrumb__link:hover {
  color: var(--ice);
  border-bottom-color: var(--red);
}

.breadcrumb__sep {
  font-family: var(--font-mono);
  color: rgba(138, 143, 153, .55);
}

.breadcrumb__item[aria-current="page"] { color: var(--ice); }

.section--light .breadcrumb__item { color: var(--ink-soft); }
.section--light .breadcrumb__link { color: var(--ink-soft); }
.section--light .breadcrumb__link:hover { color: var(--red); border-bottom-color: var(--red); }
.section--light .breadcrumb__item[aria-current="page"] { color: var(--ink); }

/* ---------- 15. 图片容器 ---------- */
.media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border-radius: var(--r-organic);
  background:
    linear-gradient(135deg, var(--night-blue) 0%, var(--ink) 58%, var(--char) 100%);
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  border: 1px solid rgba(245, 246, 248, .12);
  border-radius: inherit;
  pointer-events: none;
}

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

.media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media__caption {
  margin-top: .7rem;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .1em;
  color: var(--gray-idx);
}
.section--light .media__caption { color: var(--ink-soft); }

/* ---------- 16. 滚动显现 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}
[data-reveal].is-revealed {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  [data-reveal],
  [data-reveal].is-revealed {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .round-rail { transition: none; }
  .round-rail__tick { transition: none; }
  .nav-toggle__bars i { transition: none; }
  .site-nav { transition: none; }
  .card, .btn, .footer-nav__link { transition: none; }

  .card:hover { transform: none; }
  .btn:hover { transform: none; }
  .footer-nav__link:hover { transform: none; }
}