/* ============================================================
   三亿赛场 · Site Kit
   高原赛场数据指挥舱 / 技术蓝图式网格
   ============================================================ */

/* ---------- 01 令牌 ---------- */
:root {
  --ink-900: #071A2F;
  --ink-850: #091F38;
  --ink-800: #0C2440;
  --ink-700: #123151;
  --line: #1E3A5A;

  --ice: #E8F4FF;
  --slate: #6C8AA6;
  --cyan: #27F2D2;
  --orange: #FF7A1A;
  --clay: #B5542D;
  --teal: #0FA38E;
  --warm: #FFE8D6;

  --body-text: #C9DEF2;

  --font-head: "Arial Narrow", "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", "Cascadia Mono", Menlo, Consolas, "Noto Sans Mono CJK SC", monospace;

  --shell: 1320px;
  --gutter: clamp(16px, 4vw, 48px);
  --bar-h: 64px;
  --cut: 14px;

  --step--1: clamp(.76rem, .73rem + .18vw, .86rem);
  --step-0: clamp(.93rem, .89rem + .22vw, 1.02rem);
  --step-1: clamp(1.08rem, 1rem + .45vw, 1.32rem);
  --step-2: clamp(1.45rem, 1.18rem + 1.3vw, 2.25rem);
  --step-3: clamp(1.9rem, 1.35rem + 2.8vw, 3.4rem);
  --step-4: clamp(2.4rem, 1.5rem + 5.2vw, 5.4rem);
}

/* ---------- 02 重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.75;
  color: var(--body-text);
  overflow-wrap: break-word;
  background-color: var(--ink-900);
  background-image:
    repeating-linear-gradient(to right, rgba(30, 58, 90, .55) 0 1px, transparent 1px 68px),
    repeating-linear-gradient(to bottom, rgba(30, 58, 90, .55) 0 1px, transparent 1px 68px);
  background-attachment: fixed;
}

img, svg, video { max-width: 100%; height: auto; }
button { font: inherit; color: inherit; }
::selection { background: var(--cyan); color: var(--ink-900); }

/* ---------- 03 排版 ---------- */
h1, h2, h3, h4 {
  margin: 0 0 .55em;
  font-family: var(--font-head);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -.005em;
  color: var(--ice);
}
h1 { font-size: var(--step-4); font-weight: 900; letter-spacing: -.02em; }
h2 { font-size: var(--step-2); }
h3 { font-size: var(--step-1); }
h4 { font-size: var(--step-0); letter-spacing: .02em; }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }
strong { color: var(--ice); font-weight: 700; }
a { color: var(--cyan); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: #6FFBE4; }

.mono {
  font-family: var(--font-mono);
  font-size: .86em;
  letter-spacing: .04em;
}

.lede {
  max-width: 62ch;
  margin: 0 0 1.2em;
  font-size: var(--step-1);
  line-height: 1.72;
  color: #B7D2EA;
}

hr {
  height: 1px;
  margin: clamp(24px, 4vw, 44px) 0;
  border: 0;
  background: linear-gradient(90deg, var(--line), transparent);
}

/* ---------- 04 布局容器 ---------- */
.wrap {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.wrap--narrow { max-width: 860px; }

.grid {
  display: grid;
  gap: clamp(14px, 2vw, 26px);
}
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr)); }
.grid--aside { grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr); }

#main-content { display: block; }

/* ---------- 05 命令栏头部 ---------- */
.skip-link {
  position: absolute;
  top: -70px;
  left: 12px;
  z-index: 90;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .12em;
  color: var(--ink-900);
  background: var(--cyan);
  text-decoration: none;
  transition: top .18s ease;
}
.skip-link:focus { top: 10px; }

.cmd-bar {
  position: sticky;
  top: 0;
  z-index: 60;
  color: var(--ice);
  background: rgba(9, 31, 56, .94);
  border-bottom: 1px solid var(--line);
  -webkit-backdrop-filter: blur(9px);
  backdrop-filter: blur(9px);
}
.cmd-bar[data-shrink] {
  background: rgba(6, 21, 38, .98);
  box-shadow: 0 16px 40px -30px #000;
}
.cmd-bar::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: min(200px, 34%);
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), transparent);
}

.cmd-bar__inner {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.6vw, 24px);
  width: 100%;
  max-width: var(--shell);
  min-height: var(--bar-h);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* 品牌 */
.brand {
  display: flex;
  flex: 0 0 auto;
  align-items: baseline;
  gap: 9px;
  padding: 4px 0;
  color: var(--ice);
  text-decoration: none;
  border-bottom: 2px solid transparent;
}
.brand:hover { color: var(--ice); border-bottom-color: var(--clay); }
.brand__name {
  font-family: var(--font-head);
  font-size: 1.18rem;
  font-weight: 900;
  letter-spacing: .01em;
}
.brand__sub {
  font-family: var(--font-mono);
  font-size: .58rem;
  letter-spacing: .3em;
  color: var(--slate);
  text-transform: uppercase;
}

/* 导航 */
.site-nav {
  flex: 1 1 auto;
  min-width: 0;
}
.site-nav__list {
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: flex-end;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.site-nav__link {
  display: flex;
  align-items: baseline;
  gap: 6px;
  padding: 9px 11px;
  font-size: .85rem;
  font-weight: 600;
  letter-spacing: .01em;
  color: #B4CFE8;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 2px;
  transition: color .18s ease, background-color .18s ease, border-color .18s ease;
}
.site-nav__idx {
  font-family: var(--font-mono);
  font-size: .62rem;
  letter-spacing: .06em;
  color: var(--slate);
}
.site-nav__label { white-space: nowrap; }
.site-nav__link:hover {
  color: var(--ice);
  background: var(--ink-800);
  border-color: var(--line);
}
.site-nav__link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -3px;
}
.site-nav__link[aria-current="page"] {
  color: var(--ink-900);
  background: var(--cyan);
  border-color: var(--cyan);
}
.site-nav__link[aria-current="page"] .site-nav__idx { color: #04463D; }

/* 状态区 */
.cmd-bar__meta {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 12px;
  margin-left: 4px;
  padding-left: 14px;
  border-left: 1px solid var(--line);
}
.status {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .16em;
  color: var(--cyan);
  white-space: nowrap;
}
.status__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 0 rgba(39, 242, 210, .55);
  animation: statusPulse 2.6s ease-out infinite;
}
@keyframes statusPulse {
  0%   { box-shadow: 0 0 0 0 rgba(39, 242, 210, .5); }
  70%  { box-shadow: 0 0 0 9px rgba(39, 242, 210, 0); }
  100% { box-shadow: 0 0 0 0 rgba(39, 242, 210, 0); }
}

.cmd-bar__cta {
  display: inline-block;
  padding: 9px 16px;
  font-family: var(--font-head);
  font-size: .8rem;
  font-weight: 800;
  letter-spacing: .04em;
  color: var(--warm);
  text-decoration: none;
  background: var(--orange);
  border: 1px solid var(--orange);
  clip-path: polygon(9px 0, 100% 0, 100% calc(100% - 9px), calc(100% - 9px) 100%, 0 100%, 0 9px);
  transition: background-color .18s ease, color .18s ease;
}
.cmd-bar__cta:hover { color: #2A1200; background: #FF9147; }
.cmd-bar__cta:focus-visible { outline: 2px solid var(--ice); outline-offset: -4px; }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  margin-left: auto;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .16em;
  color: var(--ice);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 2px;
  cursor: pointer;
  transition: border-color .18s ease, color .18s ease;
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }
.nav-toggle:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }
.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 9px;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 1.5px;
  background: var(--cyan);
  transition: transform .2s ease, top .2s ease;
}
.nav-toggle__bars::before { top: 0; }
.nav-toggle__bars::after { top: 7px; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { top: 3.5px; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { top: 3.5px; transform: rotate(-45deg); }

/* ---------- 06 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 12px 20px;
  font-family: var(--font-head);
  font-size: .88rem;
  font-weight: 800;
  letter-spacing: .03em;
  color: var(--cyan);
  text-decoration: none;
  background: transparent;
  border: 1px solid var(--cyan);
  cursor: pointer;
  clip-path: polygon(9px 0, 100% 0, 100% calc(100% - 9px), calc(100% - 9px) 100%, 0 100%, 0 9px);
  transition: background-color .18s ease, color .18s ease, transform .18s ease;
}
.btn:hover { color: var(--ink-900); background: var(--cyan); transform: translateY(-1px); }
.btn:focus-visible { outline: 2px solid var(--cyan); outline-offset: -4px; }

.btn--solid { color: var(--ink-900); background: var(--cyan); }
.btn--solid:hover { background: #6FFBE4; color: var(--ink-900); }

.btn--signal { color: var(--warm); background: var(--orange); border-color: var(--orange); }
.btn--signal:hover { color: #2A1200; background: #FF9147; }

.btn--ghost { color: var(--ice); border-color: var(--line); }
.btn--ghost:hover { color: var(--ice); background: var(--ink-800); border-color: var(--slate); }

/* ---------- 07 标签 ---------- */
.tag {
  display: inline-block;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .14em;
  line-height: 1.6;
  color: var(--cyan);
  border: 1px solid currentColor;
}
.tag--clay { color: var(--clay); }
.tag--orange { color: var(--orange); }
.tag--slate { color: var(--slate); }

/* ---------- 08 面板 ---------- */
.panel {
  position: relative;
  padding: clamp(16px, 2.4vw, 30px);
  background: linear-gradient(180deg, var(--ink-800), rgba(9, 31, 56, .9));
  box-shadow: inset 0 0 0 1px var(--line);
  clip-path: polygon(
    var(--cut) 0,
    100% 0,
    100% calc(100% - var(--cut)),
    calc(100% - var(--cut)) 100%,
    0 100%,
    0 var(--cut)
  );
}
.panel > :last-child { margin-bottom: 0; }

.panel--flat {
  background: var(--ink-850);
  border: 1px solid var(--line);
  box-shadow: none;
  clip-path: none;
}
.panel--flat::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 42px;
  height: 2px;
  background: var(--clay);
}

/* ---------- 09 章节标题组 ---------- */
.sec-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  margin: 0 0 clamp(16px, 2.4vw, 28px);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}
.sec-head__idx {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .2em;
  color: var(--clay);
}
.sec-head__title {
  margin: 0;
  font-size: var(--step-2);
}
.sec-head__note {
  margin: 0 0 0 auto;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
  color: var(--slate);
}

/* ---------- 10 媒体容器 ---------- */
.media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--ink-850);
  box-shadow: inset 0 0 0 1px var(--line);
}
.media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media--wide { aspect-ratio: 21 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }

.media--grid::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(to right, rgba(39, 242, 210, .10) 0 1px, transparent 1px 24px),
    repeating-linear-gradient(to bottom, rgba(39, 242, 210, .10) 0 1px, transparent 1px 24px);
}

.media__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 8px 14px;
  font-family: var(--font-mono);
  font-size: .64rem;
  letter-spacing: .12em;
  color: var(--ice);
  background: linear-gradient(90deg, rgba(7, 26, 47, .94), rgba(7, 26, 47, 0));
}

/* ---------- 11 数据列表 ---------- */
.data-list {
  margin: 0;
  padding: 0;
  list-style: none;
}
.data-list > li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 11px 0;
  border-bottom: 1px solid rgba(30, 58, 90, .75);
}
.data-list > li:last-child { border-bottom: 0; }
.data-list__k {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .1em;
  color: var(--slate);
}
.data-list__v {
  text-align: right;
  color: var(--ice);
}

/* ---------- 12 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 26px) 0 0;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
  color: var(--slate);
}
.crumbs a {
  color: var(--slate);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.crumbs a:hover { color: var(--cyan); border-bottom-color: var(--cyan); }
.crumbs__sep { color: var(--clay); }
.crumbs [aria-current="page"] { color: var(--ice); }
.crumbs a:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

/* ---------- 13 页脚 ---------- */
.site-foot {
  position: relative;
  margin-top: clamp(48px, 7vw, 100px);
  color: #9CBAD4;
  background: linear-gradient(180deg, var(--ink-850), #040E1B);
  border-top: 1px solid var(--line);
}
.site-foot::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(260px, 42%);
  height: 2px;
  background: linear-gradient(90deg, var(--clay), transparent);
}
.site-foot__inner {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(34px, 5vw, 66px) var(--gutter) 26px;
}
.site-foot__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.1fr 1.4fr;
  gap: clamp(22px, 3vw, 46px);
}

.foot-col { min-width: 0; }
.foot-col__title {
  margin: 0 0 14px;
  padding-bottom: 9px;
  font-family: var(--font-mono);
  font-size: .66rem;
  font-weight: 600;
  letter-spacing: .22em;
  color: var(--cyan);
  text-transform: uppercase;
  border-bottom: 1px solid var(--line);
}

.foot-brand {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-size: 1.35rem;
  font-weight: 900;
  letter-spacing: .01em;
  color: var(--ice);
}
.foot-brand__line {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .18em;
  color: var(--slate);
}
.foot-brand__note {
  max-width: 36ch;
  margin: 0;
  font-size: .82rem;
  line-height: 1.85;
  color: #8FAEC8;
}

.foot-list {
  margin: 0;
  padding: 0;
  list-style: none;
}
.foot-list li + li { margin-top: 9px; }
.foot-list a {
  display: inline-block;
  padding-left: 10px;
  font-size: .86rem;
  color: #9CBAD4;
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color .18s ease, border-color .18s ease, transform .18s ease;
}
.foot-list a:hover {
  color: var(--ice);
  border-left-color: var(--cyan);
  transform: translateX(3px);
}
.foot-list a:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

.foot-contact {
  margin: 0;
  padding: 0;
  list-style: none;
}
.foot-contact li + li { margin-top: 12px; }
.foot-contact__k {
  display: block;
  margin-bottom: 3px;
  font-family: var(--font-mono);
  font-size: .64rem;
  letter-spacing: .18em;
  color: var(--clay);
}
.foot-contact__v {
  display: block;
  font-size: .86rem;
  line-height: 1.7;
  color: var(--ice);
  word-break: break-word;
}

.site-foot__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 26px;
  margin-top: clamp(28px, 4vw, 50px);
  padding-top: 20px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .07em;
  color: var(--slate);
}
.foot-legal__copy { margin: 0; }
.foot-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.foot-legal a { color: #8FAEC8; text-decoration: none; }
.foot-legal a:hover { color: var(--cyan); }
.foot-legal a:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

/* ---------- 14 动效 ---------- */
.js-on [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition:
    opacity .6s cubic-bezier(.22, .61, .36, 1),
    transform .6s cubic-bezier(.22, .61, .36, 1);
}
.js-on [data-reveal].is-in {
  opacity: 1;
  transform: none;
}

.scroll-progress {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 2;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--teal) 55%, var(--orange));
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
}

.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 30px);
  bottom: clamp(14px, 3vw, 30px);
  z-index: 70;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--ink-900);
  background: var(--cyan);
  border: 0;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  clip-path: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
  transition: opacity .22s ease, transform .22s ease, visibility .22s linear;
}
.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}
.to-top:focus-visible { outline: 2px solid var(--ice); outline-offset: -4px; }

/* ---------- 15 响应式 ---------- */
@media (max-width: 1119px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    flex: 0 0 auto;
    max-height: calc(100vh - var(--bar-h));
    padding: 8px var(--gutter) 18px;
    overflow-y: auto;
    background: var(--ink-850);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
  }
  .site-nav[data-open] {
    display: block;
    animation: navDrop .2s ease both;
  }
  @keyframes navDrop {
    from { opacity: 0; transform: translateY(-8px); }
    to   { opacity: 1; transform: none; }
  }
  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
  }
  .site-nav__item { border-bottom: 1px solid rgba(30, 58, 90, .7); }
  .site-nav__item:last-child { border-bottom: 0; }
  .site-nav__link {
    justify-content: space-between;
    padding: 14px 4px;
    font-size: 1rem;
  }
  .site-nav__idx { order: 2; }
}

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

@media (max-width: 640px) {
  :root { --bar-h: 58px; --cut: 11px; }
  .brand__sub { display: none; }
  .cmd-bar__cta { display: none; }
  .cmd-bar__meta { gap: 8px; padding-left: 10px; }
  .status { font-size: .6rem; letter-spacing: .1em; }
  .sec-head__note { margin-left: 0; flex-basis: 100%; }
}

@media (max-width: 520px) {
  .site-foot__grid { grid-template-columns: minmax(0, 1fr); }
  .site-foot__base { flex-direction: column; align-items: flex-start; }
}

/* ---------- 16 降低动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .status__dot { animation: none; }

  .js-on [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .btn:hover,
  .foot-list a:hover { transform: none; }
}