/* ==========================================================================
   雷火体育 · 全站共享样式 /assets/site.css
   暗蓝底 × 炽橙强调 × 荧光青数据 · 粗边框硬投影 · 海报式分层
   ========================================================================== */

/* ---------- 1. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 120px;
  overflow-x: clip;
}
body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }
ul, ol { list-style: none; padding: 0; }
img, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
[hidden] { display: none !important; }

/* ---------- 2. 变量 ---------- */
:root {
  --flame: #FF4D1C;
  --lava: #D6220F;
  --amber: #FF8A3D;
  --deep: #0B1B3A;
  --indigo: #16305E;
  --cyan: #21F0D6;
  --ice: #A8FFF2;
  --white: #F5F7FA;
  --ink: #111318;
  --steel: #6B7280;

  --font-sans: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-serif: "Songti SC", "Source Han Serif SC", Georgia, "Times New Roman", serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  --shell: min(1320px, calc(100% - 32px));
  --line: 2px;
  --r-sharp: 4px;
  --r-pill: 999px;
  --dur: .2s;
  --shadow-hard: 6px 6px 0 rgba(255, 77, 28, .5);
  --shadow-ink: 6px 6px 0 rgba(17, 19, 24, .9);
}

/* ---------- 3. 中文排版基调 ---------- */
body {
  font-family: var(--font-sans);
  font-size: clamp(16px, .35vw + 15px, 18px);
  line-height: 1.75;
  color: var(--ink);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, h4 { font-weight: 900; line-height: 1.08; letter-spacing: -.02em; }
h1 { font-size: clamp(2.25rem, 5.4vw, 4.5rem); }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.75rem); }
h3 { font-size: clamp(1.18rem, 1.7vw, 1.6rem); line-height: 1.25; }
strong { font-weight: 800; }

.display-xl { font-size: clamp(3rem, 10vw, 9rem); line-height: .88; font-weight: 900; letter-spacing: -.035em; }
.display-l { font-size: clamp(2.2rem, 6vw, 4.5rem); line-height: .94; font-weight: 900; letter-spacing: -.03em; }
.num { font-family: var(--font-mono); font-variant-numeric: tabular-nums; font-weight: 700; letter-spacing: -.01em; }
.mono { font-family: var(--font-mono); font-size: .78rem; letter-spacing: .16em; text-transform: uppercase; }
.serif { font-family: var(--font-serif); }
.accent { color: var(--flame); }
.accent-cyan { color: var(--cyan); }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font-mono); font-size: .76rem; letter-spacing: .18em;
  text-transform: uppercase; color: var(--flame);
}
.eyebrow::before { content: ""; width: 26px; height: 3px; background: var(--flame); }
.lede { font-family: var(--font-serif); font-size: clamp(1.1rem, 1.6vw, 1.45rem); line-height: 1.65; color: #2b3a56; max-width: 34em; }
.section--dark .lede, .section--indigo .section-head__meta, .section--dark .section-head__meta { color: var(--ice); }
.stack > * + * { margin-top: var(--stack-gap, 18px); }
.divider { height: 2px; border: 0; background: currentColor; opacity: .22; }
.slash { clip-path: polygon(0 0, 100% 2.2vw, 100% 100%, 0 calc(100% - 2.2vw)); }

/* ---------- 4. 容器与分区 ---------- */
.shell { width: var(--shell); margin-inline: auto; }
.shell--narrow { width: min(880px, calc(100% - 32px)); margin-inline: auto; }
.section { position: relative; padding: clamp(56px, 7vw, 112px) 0; }
.section--light { background: var(--white); color: var(--ink); }
.section--dark { background: var(--deep); color: var(--white); }
.section--indigo { background: var(--indigo); color: var(--white); }
.section--flame { background: var(--flame); color: #fff; }
.section--edge { border-top: 6px solid var(--flame); }
.section-head {
  display: flex; flex-wrap: wrap; gap: 14px 32px;
  align-items: flex-end; justify-content: space-between;
  margin-bottom: clamp(24px, 3vw, 44px);
}
.section-head__title { max-width: 24em; }
.section-head__meta { font-family: var(--font-mono); font-size: .8rem; letter-spacing: .1em; color: var(--steel); }

/* ---------- 5. 网格 ---------- */
.grid { display: grid; gap: clamp(16px, 2vw, 28px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--asym { grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr); }

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  padding: 12px 22px;
  border: var(--line) solid var(--ink); border-radius: var(--r-sharp);
  background: var(--white); color: var(--ink);
  font-weight: 800; letter-spacing: .02em; line-height: 1.2; cursor: pointer;
  box-shadow: 4px 4px 0 var(--ink);
  transition: transform var(--dur), box-shadow var(--dur), background var(--dur), color var(--dur);
}
.btn:hover { transform: translate(-2px, -2px); box-shadow: 6px 6px 0 var(--ink); }
.btn:active { transform: translate(2px, 2px); box-shadow: 1px 1px 0 var(--lava); }
.btn--primary { background: var(--flame); color: #fff; border-color: var(--lava); box-shadow: 4px 4px 0 var(--lava); }
.btn--primary:hover { box-shadow: 6px 6px 0 var(--lava); }
.btn--ghost { background: transparent; color: var(--ice); border-color: var(--cyan); box-shadow: 4px 4px 0 rgba(33, 240, 214, .35); }
.btn--ghost:hover { color: #fff; box-shadow: 6px 6px 0 rgba(33, 240, 214, .4); }
.btn--cyan { background: var(--cyan); color: var(--deep); border-color: #0f8f80; box-shadow: 4px 4px 0 rgba(11, 27, 58, .7); }
.btn--block { width: 100%; }

/* ---------- 7. 面包屑 ---------- */
.crumbs { margin-bottom: 20px; }
.crumbs ol { display: flex; flex-wrap: wrap; gap: 8px; font-family: var(--font-mono); font-size: .78rem; letter-spacing: .06em; color: var(--steel); }
.crumbs li + li::before { content: "/"; margin-right: 8px; color: var(--amber); }
.crumbs a:hover { color: var(--flame); }
.crumbs [aria-current="page"] { color: var(--flame); font-weight: 700; }
.section--dark .crumbs ol { color: var(--ice); }

/* ---------- 8. 正文容器 ---------- */
.prose { max-width: 68ch; }
.prose > * + * { margin-top: 1.1em; }
.prose h2 { margin-top: 2.1em; font-size: clamp(1.5rem, 2.6vw, 2.1rem); }
.prose h3 { margin-top: 1.6em; }
.prose ul, .prose ol { padding-left: 1.4em; }
.prose li { position: relative; margin-top: .5em; }
.prose li::before { content: ""; position: absolute; left: -1.2em; top: .78em; width: 12px; height: 2px; background: var(--flame); }
.prose blockquote { border-left: 6px solid var(--flame); padding: 6px 0 6px 20px; font-family: var(--font-serif); font-size: 1.3rem; line-height: 1.62; }
.prose a { color: var(--lava); font-weight: 700; border-bottom: 2px solid var(--flame); }
.prose a:hover { color: var(--flame); }
.prose code { font-family: var(--font-mono); font-size: .92em; background: rgba(33, 240, 214, .2); padding: 2px 6px; border-radius: 3px; }
.section--dark .prose a { color: var(--cyan); border-bottom-color: var(--cyan); }

/* ---------- 9. 卡片 / 标签 / 数据 ---------- */
.card {
  position: relative; background: #fff; color: var(--ink);
  border: var(--line) solid var(--ink); border-radius: var(--r-sharp);
  padding: clamp(18px, 2.2vw, 28px);
  box-shadow: var(--shadow-ink);
  transition: transform var(--dur), box-shadow var(--dur);
}
.card--dark { background: var(--indigo); color: var(--white); border-color: rgba(168, 255, 242, .3); box-shadow: var(--shadow-hard); }
.card--flame { background: var(--flame); color: #fff; border-color: var(--lava); box-shadow: 6px 6px 0 rgba(11, 27, 58, .85); }
.card--flat { box-shadow: none; }
.card__num { display: block; font-family: var(--font-mono); font-variant-numeric: tabular-nums; font-size: 2rem; font-weight: 700; line-height: 1; color: var(--flame); }
.card--flame .card__num { color: #fff; }
.card__title { margin: 10px 0 6px; font-size: 1.15rem; font-weight: 900; }
.card__text { font-size: .96rem; opacity: .86; }
.card__link { display: inline-flex; align-items: center; gap: 8px; margin-top: 14px; font-weight: 800; color: var(--flame); }
.card--dark .card__link { color: var(--cyan); }
a.card:hover { transform: translate(-3px, -3px); box-shadow: 9px 9px 0 rgba(17, 19, 24, .75); }
a.card--dark:hover { box-shadow: 9px 9px 0 rgba(255, 77, 28, .55); }

.tag {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 12px; border: var(--line) solid currentColor; border-radius: var(--r-pill);
  font-family: var(--font-mono); font-size: .74rem; letter-spacing: .08em; line-height: 1.6;
}
.tag--flame { color: var(--flame); }
.tag--cyan { color: var(--cyan); }
.tag--ink { color: var(--ink); }

.stat { display: flex; flex-direction: column; gap: 4px; }
.stat__value { font-family: var(--font-mono); font-variant-numeric: tabular-nums; font-weight: 700; font-size: clamp(1.9rem, 4.4vw, 3.4rem); line-height: 1; color: var(--flame); }
.stat__value .stat__unit { font-size: .85rem; font-weight: 700; margin-left: 4px; }
.stat__label { font-size: .84rem; letter-spacing: .04em; color: var(--steel); }
.section--dark .stat__label, .section--indigo .stat__label { color: var(--ice); opacity: .78; }
.section--dark .stat__value { color: var(--cyan); }

/* ---------- 10. 图片容器（页面阶段放图） ---------- */
.media-frame {
  position: relative; display: block; overflow: hidden;
  background: var(--deep);
  border: var(--line) solid var(--indigo); border-radius: var(--r-sharp);
  aspect-ratio: 16 / 9;
}
.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__cap {
  position: absolute; left: 0; bottom: 0;
  padding: 6px 12px; background: var(--deep); color: var(--ice);
  border-top: var(--line) solid var(--flame);
  font-family: var(--font-mono); font-size: .72rem; letter-spacing: .08em;
}
.media-frame__badge {
  position: absolute; top: 12px; left: 12px;
  padding: 4px 12px; background: var(--flame); color: #fff;
  border-radius: var(--r-pill); font-family: var(--font-mono); font-size: .72rem; font-weight: 700;
}

/* ---------- 11. 跟随目录 ---------- */
.toc {
  position: sticky; top: 112px; align-self: start;
  max-height: calc(100vh - 150px); overflow: auto;
  padding-left: 16px; border-left: var(--line) solid rgba(22, 48, 94, .25);
}
.toc__title { font-family: var(--font-mono); font-size: .72rem; letter-spacing: .2em; text-transform: uppercase; color: var(--steel); margin-bottom: 12px; }
.toc__list a {
  display: block; margin-left: -18px; padding: 7px 0 7px 16px;
  border-left: 3px solid transparent; font-size: .92rem; color: var(--steel);
  transition: color var(--dur), border-color var(--dur), background var(--dur);
}
.toc__list a:hover { color: var(--flame); }
.toc__list a[aria-current="true"] {
  color: var(--flame); font-weight: 800; border-left-color: var(--flame);
  background: linear-gradient(90deg, rgba(255, 77, 28, .16), transparent);
}
.section--dark .toc { border-left-color: rgba(168, 255, 242, .28); }
.section--dark .toc__list a, .section--dark .toc__title { color: var(--ice); opacity: .8; }
.section--dark .toc__list a[aria-current="true"] {
  color: var(--cyan); opacity: 1; border-left-color: var(--cyan);
  background: linear-gradient(90deg, rgba(33, 240, 214, .18), transparent);
}

/* ---------- 12. 页头：悬浮胶囊 ---------- */
.skip-link {
  position: fixed; top: -100px; left: 14px; z-index: 320;
  padding: 10px 18px; background: var(--flame); color: #fff;
  border-radius: var(--r-sharp); font-weight: 800;
  transition: top var(--dur);
}
.skip-link:focus { top: 14px; }

.site-header {
  position: sticky; top: 0; z-index: 200;
  padding: 10px 0 6px;
}
.header-shell {
  position: relative;
  display: flex; align-items: center; gap: clamp(8px, 1.6vw, 20px);
  width: var(--shell); margin-inline: auto;
  padding: 9px 12px 9px 16px;
  background: rgba(11, 27, 58, .95);
  border: var(--line) solid var(--indigo);
  border-radius: var(--r-pill);
  box-shadow: 5px 5px 0 rgba(255, 77, 28, .5);
  transition: padding var(--dur), box-shadow var(--dur);
}
[data-compact] .header-shell { padding: 5px 10px 5px 14px; box-shadow: 3px 3px 0 rgba(255, 77, 28, .5); }

.brand { display: inline-flex; align-items: center; gap: 10px; min-width: 0; color: var(--white); }
.brand-mark {
  display: grid; place-items: center; flex: 0 0 auto;
  width: 38px; height: 38px;
  background: var(--flame); color: #fff;
  font-size: 1.15rem; font-weight: 900; line-height: 1;
  border-radius: var(--r-sharp);
  box-shadow: 3px 3px 0 rgba(214, 34, 15, .95);
  transform: rotate(-6deg);
  transition: transform var(--dur);
}
.brand:hover .brand-mark { transform: rotate(0deg) translate(1px, -1px); }
.brand-text { display: flex; flex-direction: column; min-width: 0; line-height: 1.15; }
.brand-name { font-size: 1.05rem; font-weight: 900; letter-spacing: -.01em; white-space: nowrap; }
.brand-sub { font-family: var(--font-mono); font-size: .64rem; letter-spacing: .12em; color: var(--ice); opacity: .85; white-space: nowrap; }

.nav-current {
  display: none; align-items: center; white-space: nowrap;
  padding: 5px 12px; border-radius: var(--r-pill);
  background: rgba(255, 77, 28, .16); border: var(--line) solid rgba(255, 77, 28, .55);
  color: var(--flame); font-family: var(--font-mono); font-size: .76rem; letter-spacing: .08em;
}

.site-nav { margin-inline: auto; }
.nav-list { display: flex; align-items: center; gap: 2px; }
.nav-list a {
  display: inline-block; padding: 9px 14px; border-radius: var(--r-pill);
  color: var(--ice); font-size: .95rem; font-weight: 700;
  transition: background var(--dur), color var(--dur);
}
.nav-list a:hover { background: var(--indigo); color: #fff; }
.nav-list a[aria-current="page"] { background: var(--flame); color: #fff; box-shadow: 2px 2px 0 var(--lava); }
[data-compact] .nav-list a { padding: 7px 12px; font-size: .9rem; }

.header-actions { display: flex; align-items: center; gap: 8px; flex: 0 0 auto; }
.header-cta { border-radius: var(--r-pill); padding: 10px 18px; font-size: .9rem; }

.nav-toggle {
  display: none; align-items: center; gap: 8px;
  padding: 9px 14px; border: var(--line) solid var(--ice); border-radius: var(--r-pill);
  color: var(--ice); font-weight: 800; font-size: .88rem; cursor: pointer;
}
.nav-toggle:hover { color: #fff; border-color: var(--cyan); }
.nav-toggle__bars { display: inline-flex; flex-direction: column; gap: 4px; width: 18px; }
.nav-toggle__bars span { display: block; height: 2px; background: currentColor; transition: transform var(--dur), opacity var(--dur); }
.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); }

/* ---------- 13. 页脚 ---------- */
.site-footer {
  position: relative; overflow: hidden;
  background: var(--deep); color: var(--white);
  border-top: 6px solid var(--flame);
  padding: clamp(48px, 6vw, 84px) 0 26px;
}
.site-footer::after {
  content: ""; position: absolute; inset: auto 0 0 0; height: 2px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  opacity: .5;
}
.footer-shell { width: var(--shell); margin-inline: auto; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.3fr; gap: clamp(20px, 3vw, 48px); }
.footer-col { min-width: 0; }
.footer-col--brand .brand { margin-bottom: 14px; }
.footer-col--brand .brand-name { font-size: 1.3rem; }
.footer-title {
  margin-bottom: 14px;
  font-family: var(--font-mono); font-size: .74rem; font-weight: 700;
  letter-spacing: .2em; text-transform: uppercase; color: var(--cyan);
}
.footer-tagline { font-size: 1.02rem; font-weight: 700; color: var(--white); max-width: 22em; }
.footer-note { margin-top: 10px; font-size: .82rem; line-height: 1.7; color: rgba(168, 255, 242, .72); max-width: 30em; }
.footer-list { display: flex; flex-direction: column; gap: 2px; }
.footer-list a { display: inline-block; padding: 5px 0; color: rgba(215, 232, 255, .85); font-size: .95rem; }
.footer-list a:hover { color: var(--flame); }
.footer-list--inline { flex-direction: row; flex-wrap: wrap; gap: 6px 18px; margin-top: 14px; }
.footer-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.footer-chip {
  display: inline-block; padding: 5px 12px;
  border: var(--line) solid rgba(33, 240, 214, .45); border-radius: var(--r-pill);
  color: var(--ice); font-family: var(--font-mono); font-size: .78rem; letter-spacing: .06em;
}
.footer-contact { display: flex; flex-direction: column; gap: 8px; }
.footer-contact li { display: flex; flex-wrap: wrap; gap: 8px; font-size: .92rem; }
.footer-label { flex: 0 0 3.2em; color: var(--steel); font-family: var(--font-mono); font-size: .76rem; letter-spacing: .1em; padding-top: 3px; }
.footer-value { color: rgba(215, 232, 255, .92); word-break: break-all; }
.footer-legal {
  display: flex; flex-wrap: wrap; gap: 10px 24px; justify-content: space-between;
  margin-top: clamp(32px, 4vw, 56px); padding-top: 18px;
  border-top: var(--line) solid var(--indigo);
  font-size: .8rem; color: rgba(168, 255, 242, .6);
}
.footer-legal a { color: rgba(168, 255, 242, .6); }
.footer-legal a:hover { color: var(--flame); }

/* ---------- 14. 由脚本注入的滚动辅助 ---------- */
.scroll-progress {
  position: fixed; top: 0; left: 0; z-index: 240;
  width: 0; height: 4px; pointer-events: none;
  background: linear-gradient(90deg, var(--flame), var(--amber) 55%, var(--cyan));
}
.to-top {
  position: fixed; right: 18px; bottom: 22px; z-index: 230;
  width: 52px; height: 52px; display: grid; place-items: center;
  border-radius: var(--r-pill); border: var(--line) solid var(--cyan);
  background: var(--deep); color: var(--ice);
  font-size: 1.2rem; font-weight: 900; cursor: pointer;
  box-shadow: 4px 4px 0 rgba(255, 77, 28, .55);
  transition: transform var(--dur), box-shadow var(--dur), color var(--dur);
}
.to-top:hover { color: var(--flame); transform: translate(-2px, -2px); box-shadow: 6px 6px 0 rgba(255, 77, 28, .6); }

/* ---------- 15. 显现 ---------- */
.js-ready [data-reveal] { opacity: 0; transform: translateY(12px); transition: opacity .5s ease, transform .5s ease; }
.js-ready [data-reveal].is-inview { opacity: 1; transform: none; }

/* ---------- 16. 焦点可见 ---------- */
:focus-visible { outline: 3px solid var(--cyan); outline-offset: 2px; border-radius: 2px; }
.section--light :focus-visible, body :focus-visible { outline-color: var(--flame); }
.section--dark :focus-visible, .site-footer :focus-visible, .site-header :focus-visible { outline-color: var(--cyan); }

/* ---------- 17. 响应式 ---------- */
@media (max-width: 1120px) {
  .brand-sub { display: none; }
  .nav-list a { padding: 8px 11px; font-size: .9rem; }
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer-col:last-child { grid-column: 1 / -1; }
}

@media (max-width: 920px) {
  .header-shell { border-radius: 20px; padding: 8px 10px; }
  .nav-current { display: none !important; }
  .site-nav {
    position: absolute; top: calc(100% + 10px); left: 0; right: 0;
    display: none; margin: 0; padding: 10px;
    background: var(--deep); border: var(--line) solid var(--indigo); border-radius: 16px;
    box-shadow: 8px 8px 0 rgba(255, 77, 28, .45);
    max-height: calc(100vh - 150px); overflow: auto;
  }
  .site-nav[data-open] { display: block; }
  .nav-list { flex-direction: column; align-items: stretch; gap: 2px; }
  .nav-list a { display: block; width: 100%; padding: 12px 14px; border-radius: 10px; font-size: 1rem; }
  .nav-toggle { display: inline-flex; }
  .header-actions { margin-left: auto; }

  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--asym { grid-template-columns: minmax(0, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px 24px; }
  .toc { position: static; max-height: none; margin-bottom: 24px; }
}

@media (max-width: 600px) {
  .section { padding: clamp(40px, 10vw, 64px) 0; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-col:last-child { grid-column: auto; }
  .footer-legal { flex-direction: column; gap: 8px; }
  .to-top { right: 12px; bottom: 16px; width: 46px; height: 46px; }
}

@media (max-width: 480px) {
  .nav-toggle__text { display: none; }
  .header-cta { padding: 9px 13px; font-size: .84rem; }
  .brand-mark { width: 34px; height: 34px; font-size: 1rem; }
}

/* ---------- 18. 减少动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; scroll-padding-top: 100px; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .js-ready [data-reveal] { opacity: 1 !important; transform: none !important; }
  .btn:hover, a.card:hover, .to-top:hover, .brand:hover .brand-mark { transform: none; }
}