/* =========================================================
   四季体育安装 — 共享样式 /assets/site.css
   色板：夜场墨绿 · 荧光青 · 战报暖橙
   ========================================================= */

/* ---------- 01 reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }
ul[class], ol[class] { list-style: none; padding: 0; }
img, svg, video, picture { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; }
table { border-collapse: collapse; width: 100%; }
[hidden] { display: none !important; }

/* ---------- 02 变量 ---------- */
:root {
  --ink: #0A1A13;
  --ink-2: #10241A;
  --line: #1E3A2C;
  --cyan: #37F5C1;
  --cyan-soft: #8CFFE0;
  --orange: #FF8A3D;
  --amber: #C2561B;
  --paper: #F2F5F0;
  --muted: #7E9488;
  --black: #050C09;

  --gutter: clamp(18px, 4.2vw, 48px);
  --maxw: 1680px;
  --maxw-read: 62ch;
  --header-h: 68px;

  --u: 8px;
  --sp-s: calc(var(--u) * 6);
  --sp-m: calc(var(--u) * 9);
  --sp-l: calc(var(--u) * 15);

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

  --dur: 220ms;
  --ease: cubic-bezier(.2, .7, .3, 1);
}

/* ---------- 03 基础排版 ---------- */
body {
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.8;
  letter-spacing: .01em;
  font-weight: 400;
  min-height: 100vh;
  overflow-x: hidden;
}

h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 600; line-height: 1.25; letter-spacing: -.01em; }
h1 { font-size: clamp(40px, 6vw, 72px); }
h2 { font-size: clamp(26px, 3vw, 36px); }
h3 { font-size: clamp(19px, 2vw, 23px); }
p { text-wrap: pretty; }

::selection { background: var(--cyan); color: var(--ink); }

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

[id] { scroll-margin-top: calc(var(--header-h) + 20px); }

/* ---------- 04 跳至内容 ---------- */
.skip-link {
  position: absolute;
  left: var(--gutter);
  top: 10px;
  z-index: 300;
  display: inline-block;
  padding: 9px 16px;
  background: var(--cyan);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  text-decoration: none;
  transform: translateY(-200%);
  transition: transform var(--dur) var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- 05 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background: var(--ink);
  border-bottom: 1px solid var(--line);
}

.header-grid {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 20px;
  width: 100%;
  max-width: var(--maxw);
  min-height: var(--header-h);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  padding: 12px 0;
  min-width: 0;
}
.brand-mark {
  flex: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 2px;
  width: 22px;
  height: 22px;
}
.brand-mark i { display: block; background: var(--line); transition: background var(--dur) var(--ease); }
.brand-mark i:nth-child(1) { background: var(--cyan); }
.brand-mark i:nth-child(4) { background: var(--orange); }
.brand:hover .brand-mark i:nth-child(2) { background: var(--cyan-soft); }
.brand:hover .brand-mark i:nth-child(3) { background: var(--amber); }

.brand-text { display: flex; flex-direction: column; min-width: 0; }
.brand-line {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: .04em;
  line-height: 1.25;
  color: var(--paper);
  white-space: nowrap;
}
.brand-note {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  line-height: 1.5;
  color: var(--muted);
  white-space: nowrap;
  text-transform: uppercase;
}

/* 命令栏导航 */
.cmd-nav { justify-self: center; min-width: 0; }
.cmd-nav-list {
  display: flex;
  align-items: center;
  gap: 0;
  list-style: none;
  margin: 0;
  padding: 0;
}
.cmd-link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 7px;
  padding: 10px 13px;
  font-size: 14px;
  line-height: 1.4;
  color: var(--paper);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  background: transparent;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.cmd-index {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  color: var(--muted);
  transition: color var(--dur) var(--ease);
}
.cmd-label { white-space: nowrap; }

.cmd-link:hover { color: var(--cyan-soft); background: rgba(55, 245, 193, .06); }
.cmd-link:hover .cmd-index { color: var(--cyan); }

.cmd-link[aria-current="page"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
  background: rgba(55, 245, 193, .08);
}
.cmd-link[aria-current="page"] .cmd-index { color: var(--cyan); }

/* 右侧元信息 */
.header-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  justify-self: end;
}
.version-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 11px;
  border: 1px solid var(--line);
  background: var(--ink-2);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
  white-space: nowrap;
}
.version-num { color: var(--cyan); font-variant-numeric: tabular-nums; }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  justify-self: end;
  padding: 10px 12px;
  border: 1px solid var(--line);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }
.nav-toggle-label { white-space: nowrap; }
.nav-toggle-bars { display: grid; gap: 4px; width: 18px; }
.nav-toggle-bars i {
  display: block;
  height: 1px;
  background: var(--cyan);
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:first-child { transform: translateY(2.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:last-child { transform: translateY(-2.5px) rotate(-45deg); }

/* 阅读进度刻度 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  pointer-events: none;
}
.scroll-progress > span {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--cyan-soft) 55%, var(--orange) 100%);
  transition: width 90ms linear;
}

/* ---------- 06 页脚 ---------- */
.site-footer {
  position: relative;
  background: var(--black);
  border-top: 1px solid var(--line);
  color: var(--muted);
  margin-top: auto;
}
.footer-inner {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding: var(--sp-m) var(--gutter) 28px;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(230px, .9fr) minmax(0, 2.4fr);
  gap: var(--sp-m);
  padding-bottom: var(--sp-s);
  border-bottom: 1px solid var(--line);
}

.footer-brand-line {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--paper);
}
.footer-tagline {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--cyan);
}
.footer-brand-note {
  margin-top: 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 34ch;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr)) minmax(210px, 1.25fr);
  gap: 32px 24px;
}
.footer-col-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--paper);
  padding-bottom: 10px;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.footer-links { list-style: none; margin: 0; padding: 0; display: grid; gap: 9px; }
.footer-links a {
  position: relative;
  display: inline-block;
  font-size: 14px;
  line-height: 1.6;
  color: var(--muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}
.footer-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  height: 1px;
  width: 0;
  background: var(--cyan);
  transition: width var(--dur) var(--ease);
}
.footer-links a:hover { color: var(--cyan-soft); }
.footer-links a:hover::after { width: 100%; }

.footer-contact { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.footer-contact-item { display: grid; gap: 3px; }
.footer-contact-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--line);
}
.footer-contact-value {
  font-size: 14px;
  line-height: 1.65;
  color: var(--paper);
  word-break: break-word;
}
.footer-contact-item:first-child .footer-contact-value,
.footer-contact-item:nth-child(2) .footer-contact-value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .02em;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  padding-top: 22px;
}
.footer-legal-line {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}
.footer-copy {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}

/* 返回顶部 */
.to-top {
  position: fixed;
  right: var(--gutter);
  bottom: var(--gutter);
  z-index: 110;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  background: var(--ink-2);
  border: 1px solid var(--line);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease),
              background var(--dur) var(--ease), border-color var(--dur) var(--ease),
              color var(--dur) var(--ease), visibility var(--dur);
}
.to-top[data-visible] { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--orange); border-color: var(--orange); color: #160600; }

/* ---------- 07 布局工具 ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.section { padding-block: var(--sp-m); }
.section--tight { padding-block: var(--sp-s); }
.section--loose { padding-block: var(--sp-l); }
.section--alt { background: var(--ink-2); }

.grid { display: grid; gap: var(--sp-s); }
.grid-12 { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--sp-s); }
.stack { display: grid; gap: 16px; }

/* ---------- 08 章节头与索引 ---------- */
.eyebrow,
.index-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
}
.index-label { color: var(--cyan); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 18px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  margin-bottom: 28px;
}
.section-index {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
  flex: none;
}
.section-title { font-size: clamp(24px, 3vw, 34px); font-weight: 600; }
.section-note {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}

.rule { border: 0; border-top: 1px solid var(--line); margin: 0; }

/* ---------- 09 正文与面包屑 ---------- */
.prose {
  max-width: var(--maxw-read);
  font-size: 17px;
  line-height: 1.85;
  color: var(--paper);
}
.prose p + p { margin-top: 1.05em; }
.prose h2, .prose h3 { margin-top: 1.6em; margin-bottom: .5em; }
.prose ul, .prose ol { margin-top: .8em; padding-left: 1.25em; }
.prose li + li { margin-top: .35em; }
.prose a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
.prose a:hover { color: var(--cyan-soft); }
.prose strong { color: var(--cyan-soft); font-weight: 600; }

.breadcrumbs {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
}
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.breadcrumb-item { color: var(--muted); }
.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin-right: 8px;
  color: var(--line);
}
.breadcrumb-item a { color: var(--muted); text-decoration: none; transition: color var(--dur) var(--ease); }
.breadcrumb-item a:hover { color: var(--cyan); }
.breadcrumb-item[aria-current="page"] { color: var(--paper); }

/* ---------- 10 按钮与标签 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 11px 18px;
  border: 1px solid var(--line);
  background: transparent;
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  text-transform: uppercase;
  text-decoration: none;
  line-height: 1.4;
  white-space: nowrap;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
              border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.btn:hover { border-color: var(--cyan); color: var(--cyan); }
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--orange);
  border-color: var(--orange);
  color: #160600;
  font-weight: 600;
}
.btn-primary:hover { background: var(--amber); border-color: var(--amber); color: var(--paper); }

.btn-ghost { border-color: var(--line); color: var(--muted); }
.btn-ghost:hover { border-color: var(--cyan); color: var(--cyan); }

.btn--block { width: 100%; }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 9px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
  white-space: nowrap;
}
.tag--cyan { color: var(--cyan); border-color: rgba(55, 245, 193, .42); background: rgba(55, 245, 193, .06); }
.tag--orange { color: var(--orange); border-color: rgba(255, 138, 61, .45); background: rgba(255, 138, 61, .07); }

/* ---------- 11 数字与数据排版 ---------- */
.num,
.stat-value,
.score {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
}
.stat-value { font-size: clamp(30px, 4vw, 52px); line-height: 1; color: var(--cyan); }
.score { font-size: clamp(24px, 3vw, 40px); line-height: 1; color: var(--orange); }

/* ---------- 12 图片容器 ---------- */
.img-frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--ink-2);
  border: 1px solid var(--line);
  overflow: hidden;
}
.img-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 600ms var(--ease), filter var(--dur) var(--ease);
}
.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(30, 58, 44, .55) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 58, 44, .55) 1px, transparent 1px);
  background-size: 44px 44px;
  opacity: .5;
  mix-blend-mode: screen;
}
.img-frame:hover img { transform: scale(1.02); }
.img-frame--wide { aspect-ratio: 21 / 9; }
.img-frame--portrait { aspect-ratio: 3 / 4; }
.img-frame--square { aspect-ratio: 1 / 1; }

.figure-caption {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}

/* ---------- 13 入场显现 ---------- */
html.js-reveal [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 520ms var(--ease), transform 520ms var(--ease);
}
html.js-reveal [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 14 响应式 ---------- */
@media (max-width: 1279px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px 24px; }
  .footer-top { grid-template-columns: 1fr; gap: var(--sp-s); }
  .footer-brand-note { max-width: 48ch; }
}

@media (max-width: 1079px) {
  .header-grid {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 12px;
  }
  .brand { justify-self: start; }
  .header-meta { display: none; }
  .nav-toggle { display: inline-flex; }

  .cmd-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    z-index: 140;
    justify-self: stretch;
    background: var(--ink-2);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    max-height: 76vh;
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    pointer-events: none;
    transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease), visibility var(--dur);
  }
  .cmd-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: none;
    pointer-events: auto;
  }
  .cmd-nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px var(--gutter) 18px;
    max-width: var(--maxw);
    margin-inline: auto;
  }
  .cmd-link {
    align-items: center;
    padding: 14px 4px;
    font-size: 16px;
    border-bottom: 1px solid var(--line);
    border-left: 2px solid transparent;
  }
  .cmd-link:hover { border-left-color: var(--cyan); }
  .cmd-link[aria-current="page"] {
    border-bottom-color: var(--line);
    border-left-color: var(--cyan);
    background: rgba(55, 245, 193, .08);
  }
  .cmd-index { font-size: 11px; }
}

@media (max-width: 860px) {
  :root { --sp-l: calc(var(--u) * 10); --sp-m: calc(var(--u) * 7); }
  body { font-size: 16px; line-height: 1.8; }
  .footer-inner { padding-bottom: 22px; }
}

@media (max-width: 620px) {
  .brand-note { display: none; }
  .footer-grid { grid-template-columns: 1fr; gap: 26px; }
  .footer-legal { flex-direction: column; align-items: flex-start; gap: 8px; }
  .nav-toggle-label { display: none; }
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .to-top { width: 40px; height: 40px; right: 16px; bottom: 16px; }
}

@media (max-width: 420px) {
  .brand-line { font-size: 15px; }
  .btn { padding: 10px 14px; font-size: 11px; }
}

/* ---------- 15 减低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
  html.js-reveal [data-reveal] { opacity: 1; transform: none; }
  .scroll-progress > span { transition: none; }
}