:root {
  --yq-night: #0A1428;
  --yq-ink: #1E293B;
  --yq-gray: #64748B;
  --yq-bg: #F1F5F9;
  --yq-white: #FFFFFF;
  --yq-red: #E63946;
  --yq-green: #2A9D8F;
  --yq-gold: #E9C46A;
  --yq-blue: #0EA5E9;
  --yq-violet: #7C3AED;
  --yq-border: #C8D2DC;
  --font-serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Georgia, "Noto Serif SC", "Songti SC", serif;
  --font-sans: "Avenir Next", Avenir, "Segoe UI", "Helvetica Neue", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Roboto Mono", "Liberation Mono", "Courier New", monospace;
  --header-h: auto;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--yq-ink);
  background: var(--yq-bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  font-weight: 900;
  line-height: 1.2;
  margin: 0 0 0.5em;
  color: var(--yq-ink);
}

p {
  margin: 0 0 1em;
}

a {
  color: var(--yq-blue);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.15em;
}

a:hover {
  color: var(--yq-red);
}

input, button {
  font: inherit;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  display: inline-block;
  padding: 0.75em 1.2em;
  background: var(--yq-red);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  border-radius: 0 0 4px 0;
}

.skip-link:focus {
  left: 0;
  color: #fff;
}

:focus-visible {
  outline: 3px solid var(--yq-blue);
  outline-offset: 2px;
}

.container {
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: clamp(16px, 4vw, 48px);
}

.btn {
  display: inline-block;
  padding: 0.7em 1.4em;
  background: var(--yq-red);
  color: #fff;
  border: 0;
  border-radius: 2px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 0.9rem;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  color: #fff;
  background: #c31f2c;
}

.btn--ghost {
  background: transparent;
  border: 1px solid currentColor;
  color: var(--yq-ink);
}

.btn--ghost:hover {
  background: rgba(30, 41, 59, 0.06);
  color: var(--yq-ink);
}

.btn--green {
  background: var(--yq-green);
}

.btn--green:hover {
  background: #1f8074;
}

.btn--gold {
  background: var(--yq-gold);
  color: var(--yq-ink);
}

.btn--gold:hover {
  background: #d8af50;
  color: var(--yq-ink);
}

.breadcrumb {
  font-size: 0.8rem;
  color: var(--yq-gray);
  margin: 1em 0;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: clamp(16px, 4vw, 48px);
}

.breadcrumb a {
  color: var(--yq-blue);
  text-decoration: none;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

.breadcrumb [aria-current] {
  color: var(--yq-ink);
  font-weight: 600;
}

.prose {
  max-width: 70ch;
  font-size: 1rem;
  line-height: 1.7;
}

.prose p {
  margin: 0 0 1em;
}

.prose a {
  color: var(--yq-blue);
}

.prose a:hover {
  color: var(--yq-red);
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 72px);
  align-items: start;
}

.split--wide {
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
}

.grid {
  display: grid;
  gap: 24px;
}

.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));
}

.card {
  position: relative;
  background: var(--yq-white);
  border: 1px solid var(--yq-border);
  border-radius: 4px;
  padding: 1.5em;
  box-shadow: 0 1px 3px rgba(2, 8, 22, 0.08);
}

.card--dark {
  background: var(--yq-night);
  border-color: var(--yq-night);
  color: #fff;
}

.card--dark .card__title {
  color: #fff;
}

.card--skew {
  transform: rotate(-1deg);
}

.card__title {
  font-size: 1.35rem;
  margin-top: 0;
}

.card__meta {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--yq-gray);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--yq-blue);
  border-left: 3px solid var(--yq-red);
  padding-left: 0.5em;
  margin-bottom: 1em;
}

.page-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  line-height: 1.05;
  margin-bottom: 0.3em;
}

.page-subtitle {
  font-size: 1.1rem;
  color: var(--yq-gray);
  max-width: 60ch;
}

.lede {
  font-size: 1.15rem;
  color: #334155;
  line-height: 1.7;
}

.data-badge {
  display: inline-block;
  background: var(--yq-red);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.15em 0.6em;
  border-radius: 2px;
  letter-spacing: 0.04em;
}

.tag {
  display: inline-block;
  border: 1px solid currentColor;
  padding: 0.2em 0.7em;
  font-size: 0.75rem;
  line-height: 1.4;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border-radius: 999px;
  color: var(--yq-gray);
}

.tag--blue {
  color: var(--yq-blue);
  border-color: var(--yq-blue);
}

.tag--purple {
  color: var(--yq-violet);
  border-color: var(--yq-violet);
}

.tag--gold {
  color: #b4802a;
  border-color: #d9b96a;
  background: rgba(233, 196, 106, 0.12);
}

.tag--green {
  color: var(--yq-green);
  border-color: var(--yq-green);
}

.media-frame {
  position: relative;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, #dce4ec 0%, #b8c4d0 100%);
  border: 1px solid #aeb8c3;
  border-radius: 4px;
  overflow: hidden;
  min-height: 180px;
}

.media-frame::after {
  content: "球事影像";
  position: absolute;
  inset: auto 0 0 0;
  padding: 0.4em 0.8em;
  background: rgba(10, 20, 40, 0.7);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.media-frame--tilt {
  transform: rotate(1.5deg);
}

.media-frame--night {
  background: linear-gradient(135deg, #0A1428, #1E3A5F);
}

.media-frame--night::after {
  content: "数据回放";
}

.paper-stack {
  position: relative;
}

.paper-stack::before,
.paper-stack::after {
  content: "";
  position: absolute;
  inset: 12px -4px -4px 12px;
  background: rgba(10, 20, 40, 0.08);
  border: 1px solid #d4dde5;
  border-radius: 2px;
  z-index: -1;
}

.paper-stack::after {
  inset: 24px -8px -8px 24px;
  opacity: 0.6;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--yq-night);
  color: #fff;
  border-bottom: 3px solid var(--yq-red);
  box-shadow: 0 2px 12px rgba(10, 20, 40, 0.35);
}

.site-progress {
  position: absolute;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--yq-green), var(--yq-blue));
  z-index: 5;
  border-radius: 0 2px 2px 0;
  pointer-events: none;
}

.site-header__rail {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
  max-width: 1280px;
  margin-inline: auto;
  padding: 12px clamp(16px, 4vw, 48px);
}

.site-header__edition {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--yq-gold);
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6em;
  color: #fff;
  text-decoration: none;
}

.site-header__brand:hover {
  color: #fff;
}

.site-header__mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  background: var(--yq-red);
  color: #fff;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 1.5rem;
  line-height: 1;
  border-radius: 2px;
  transform: rotate(-4deg);
  box-shadow: 4px 4px 0 var(--yq-gold);
}

.site-header__name {
  display: block;
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 0.04em;
}

.site-header__name span {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--yq-gold);
}

.site-header__tools {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 8px;
}

.site-search {
  display: flex;
  align-items: center;
  background: #12233f;
  border: 1px solid #233d5f;
  border-radius: 999px;
  padding: 4px 6px 4px 12px;
}

.site-search__input {
  width: 130px;
  background: transparent;
  border: 0;
  outline: 0;
  color: #fff;
  font-size: 0.8rem;
  font-family: var(--font-sans);
}

.site-search__input::placeholder {
  color: rgba(255, 255, 255, 0.6);
}

.site-search__button {
  background: var(--yq-red);
  color: #fff;
  border: 0;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  line-height: 1;
  padding: 0.4em 0.8em;
  cursor: pointer;
}

.site-search__button:hover {
  background: #c31f2c;
}

.site-favbutton {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.35);
  color: #fff;
  border-radius: 4px;
  padding: 0.45em 0.8em;
  font-size: 0.75rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.site-favbutton[aria-pressed="true"] {
  background: var(--yq-green);
  border-color: var(--yq-green);
  color: #fff;
}

.site-header__navrow {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.site-nav {
  flex: 1;
  display: flex;
  justify-content: center;
}

.site-nav__list {
  display: flex;
  justify-content: center;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-nav__link {
  display: block;
  padding: 0.9em 1.25em;
  color: rgba(255, 255, 255, 0.85);
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  border-bottom: 3px solid transparent;
  transition: color 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.site-nav__link:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.06);
}

.site-nav__link[aria-current="page"] {
  color: var(--yq-gold);
  border-bottom-color: var(--yq-gold);
}

.site-header__toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 0;
  padding: 10px 14px;
  margin: 4px;
  cursor: pointer;
}

.site-header__toggle-line {
  display: block;
  width: 22px;
  height: 2px;
  background: #fff;
  margin: 3px 0;
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(2) {
  opacity: 0;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* ---------- Footer ---------- */
.site-footer {
  background: var(--yq-night);
  color: rgba(255, 255, 255, 0.8);
  border-top: 3px solid var(--yq-gold);
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr;
  gap: 40px;
  max-width: 1280px;
  margin-inline: auto;
  padding: 48px clamp(16px, 4vw, 48px) 24px;
}

.site-footer__block {
  min-width: 0;
}

.site-footer__block--brand {
  max-width: 480px;
}

.site-footer__brand {
  margin: 0 0 0.4em;
  font-family: var(--font-serif);
  font-size: 1.4rem;
  font-weight: 900;
  color: #fff;
  line-height: 1.2;
}

.site-footer__brand span {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--yq-gold);
}

.site-footer__trust {
  margin: 12px 0 0;
  font-size: 0.85rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.7);
}

.site-footer__heading {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--yq-gold);
  margin: 0 0 16px;
}

.site-footer__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer__list a {
  display: inline-block;
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  font-size: 0.9rem;
  line-height: 2.2;
  border-bottom: 1px solid transparent;
}

.site-footer__list a:hover {
  color: var(--yq-gold);
  border-bottom-color: var(--yq-gold);
}

.site-footer__contact p {
  font-size: 0.85rem;
  margin: 0 0 8px;
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.8);
}

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-top: 8px;
}

.site-footer__legal a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.8rem;
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.site-footer__legal a:hover {
  color: var(--yq-gold);
  border-bottom-color: var(--yq-gold);
}

.site-footer__icp {
  margin: 16px 0 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.5);
}

.site-footer__colophon {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  max-width: 1280px;
  margin-inline: auto;
  padding: 16px clamp(16px, 4vw, 48px);
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.6);
}

.site-footer__colophon p {
  margin: 0;
}

.site-footer__colophon a {
  color: rgba(255, 255, 255, 0.6);
  text-decoration: none;
}

.site-footer__colophon a:hover {
  color: #fff;
}

/* ---------- Responsive ---------- */
@media (max-width: 920px) {
  .split,
  .split--wide {
    grid-template-columns: minmax(0, 1fr);
  }

  .grid--4,
  .grid--3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .site-footer__grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .site-footer__block--brand {
    grid-column: 1 / -1;
    max-width: none;
  }
}

@media (max-width: 860px) {
  .site-header__rail {
    grid-template-columns: auto 1fr auto;
    gap: 12px;
  }

  .site-header__edition {
    display: none;
  }

  .site-header__brand {
    justify-self: center;
  }

  .site-header__mark {
    width: 36px;
    height: 36px;
    font-size: 1.25rem;
  }

  .site-header__name {
    font-size: 1.1rem;
  }

  .site-search__input {
    width: 80px;
  }

  .site-header__toggle {
    display: inline-flex;
  }

  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--yq-night);
    box-shadow: 0 16px 20px rgba(2, 8, 22, 0.35);
    padding: 0 16px 16px;
  }

  .site-nav[data-open] {
    display: block;
  }

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

  .site-nav__link {
    padding: 0.8em 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.12);
    border-left: 3px solid transparent;
  }

  .site-nav__link[aria-current="page"] {
    border-left-color: var(--yq-gold);
    border-bottom-color: transparent;
    background: rgba(255, 255, 255, 0.04);
  }

  .site-header__navrow {
    justify-content: flex-end;
  }
}

@media (max-width: 620px) {
  .site-header__tools {
    gap: 4px;
  }

  .site-search__input {
    width: 64px;
  }

  .site-favbutton {
    font-size: 0.65rem;
    padding: 0.35em 0.6em;
  }

  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: minmax(0, 1fr);
  }

  .site-footer__grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .site-footer__block--brand {
    grid-column: auto;
  }

  .site-footer__colophon {
    flex-direction: column;
    text-align: center;
  }
}

/* ---------- Motion ---------- */
html.js-anim [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.35s ease, transform 0.35s ease;
}

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

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html.js-anim [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .site-progress {
    display: none;
  }
}