/* =========================================================
   光速赛场 · 共享样式表 /assets/site.css
   夜间赛道记分屏：深空底 · 极速青数据层 · 信号橙行动层
   ========================================================= */

/* ---------- 1. 变量 ---------- */
:root {
  color-scheme: dark;

  --ink-900: #070B14;
  --ink-800: #0D1424;
  --ink-700: #141E33;
  --cyan: #22D3EE;
  --cyan-deep: #0E7490;
  --orange: #FF6B2C;
  --orange-deep: #C2410C;
  --white: #F4F8FF;
  --mist: #9FB0C8;
  --focus: #A5F3FC;

  --line: rgba(159, 176, 200, .20);
  --line-strong: rgba(159, 176, 200, .42);
  --tint-cyan: rgba(34, 211, 238, .10);
  --tint-orange: rgba(255, 107, 44, .12);
  --on-signal: #1A0A02;

  --font-display: "Archivo Black", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-num: "IBM Plex Mono", "JetBrains Mono", SFMono-Regular, Consolas, monospace;

  --shell-max: 1440px;
  --shell-pad: clamp(20px, 4vw, 56px);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --ease-std: 180ms cubic-bezier(.4, 0, .2, 1);
}

/* ---------- 2. 重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ul, ol { margin: 0; }

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

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

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

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 3px;
  box-shadow: 0 0 0 1px rgba(7, 11, 20, .92);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  overflow-x: hidden;
  font-family: var(--font-body);
  font-size: clamp(15.5px, 1.02vw, 17px);
  line-height: 1.75;
  color: var(--white);
  background-color: var(--ink-900);
  background-image:
    radial-gradient(1100px 560px at 10% -12%, rgba(34, 211, 238, .10), transparent 62%),
    radial-gradient(900px 520px at 96% 2%, rgba(255, 107, 44, .09), transparent 64%);
  background-repeat: no-repeat;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection { background: var(--cyan); color: #04141A; }

.display {
  font-family: var(--font-display);
  font-weight: 400;
  line-height: .95;
  letter-spacing: -.022em;
}

.num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
}

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

/* ---------- 4. 容器与页面骨架 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: var(--shell-pad);
}

.page-main {
  padding-block: clamp(24px, 4vw, 56px) clamp(44px, 6vw, 96px);
}

.section { padding-block: clamp(32px, 5vw, 72px); }

.section-head {
  display: grid;
  gap: 12px;
  max-width: 78ch;
  margin-bottom: clamp(22px, 3vw, 36px);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 40px);
  line-height: 1.06;
  letter-spacing: -.02em;
}

.section-note {
  max-width: 64ch;
  color: var(--mist);
  font-size: 15.5px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  flex: none;
  width: 24px;
  height: 1px;
  background: var(--orange);
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: .01em;
  text-align: center;
  white-space: nowrap;
  transition:
    background-color var(--ease-std),
    color var(--ease-std),
    border-color var(--ease-std),
    transform var(--ease-std),
    box-shadow var(--ease-std);
}

.btn:active { transform: translateY(1px); }

.btn--signal {
  background: var(--orange);
  color: var(--on-signal);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .24);
}

.btn--signal:hover { background: #FF8347; }

.btn--signal:active {
  background: var(--orange-deep);
  color: var(--white);
}

.btn--ghost {
  background: var(--tint-cyan);
  border-color: var(--line-strong);
  color: var(--white);
}

.btn--ghost:hover {
  border-color: var(--cyan);
  color: var(--cyan);
  background: rgba(34, 211, 238, .17);
}

.btn--line {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--mist);
}

.btn--line:hover {
  border-color: var(--white);
  color: var(--white);
}

/* ---------- 6. 跳至正文 ---------- */
.skip-link {
  position: fixed;
  left: clamp(12px, 3vw, 24px);
  top: -90px;
  z-index: 300;
  display: inline-block;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  background: var(--cyan);
  color: #04141A;
  font-size: 14px;
  font-weight: 700;
  transition: top var(--ease-std);
}

.skip-link:focus { top: 12px; }

/* ---------- 7. 页头 ---------- */
.site-header {
  position: relative;
  z-index: 80;
  background: var(--ink-900);
}

.scroll-meter {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--cyan) 55%, var(--orange) 100%);
  pointer-events: none;
}

/* 7.1 上层状态带 */
.header-utility {
  background: var(--ink-800);
  border-bottom: 1px solid var(--line);
}

.header-utility__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 2px clamp(10px, 3vw, 40px);
  padding-block: 7px;
  font-family: var(--font-num);
  font-size: 11.5px;
  line-height: 1.5;
  letter-spacing: .05em;
  color: var(--mist);
}

.header-utility__lead {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--white);
}

.header-utility__lead::before {
  content: "";
  flex: none;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(34, 211, 238, .14);
}

.header-utility__meta { color: rgba(159, 176, 200, .78); }

/* 7.2 下层品牌栏 */
.header-main {
  position: relative;
  background: rgba(13, 20, 36, .96);
}

.header-main::before {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 1px;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(159, 176, 200, .38) 0 1px,
    transparent 1px 10px
  );
}

.header-main::after {
  content: "";
  position: absolute;
  left: var(--shell-pad);
  bottom: 0;
  width: min(180px, 24vw);
  height: 2px;
  background: var(--orange);
  transform: skewX(-28deg);
  transform-origin: left center;
}

.header-main__inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(14px, 3vw, 40px);
  min-height: clamp(66px, 7vw, 84px);
  padding-block: 10px;
}

/* 7.3 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: none;
  color: var(--white);
}

.brand__mark {
  position: relative;
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  flex: none;
  border: 1px solid var(--line-strong);
  border-radius: 9px;
  background: linear-gradient(160deg, var(--ink-700), var(--ink-900));
}

.brand__mark::before {
  content: "";
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 2px solid var(--cyan);
  border-right-color: var(--orange);
  border-bottom-color: var(--orange);
  transform: rotate(-35deg);
}

.brand__mark::after {
  content: "";
  position: absolute;
  top: 6px;
  left: 50%;
  width: 1px;
  height: 5px;
  background: var(--orange);
  transform: translateX(-50%);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.brand__name {
  font-family: var(--font-display);
  font-size: clamp(17px, 1.6vw, 20px);
  line-height: 1;
  letter-spacing: .02em;
}

.brand__tag {
  font-family: var(--font-num);
  font-size: 9px;
  line-height: 1;
  letter-spacing: .32em;
  text-transform: uppercase;
  color: var(--cyan);
}

/* 7.4 折叠按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 14px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  color: var(--white);
  font-size: 13px;
  font-weight: 500;
  transition: border-color var(--ease-std), color var(--ease-std);
}

.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }

.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 16px;
}

.nav-toggle__bars span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
  transition: transform var(--ease-std), opacity var(--ease-std);
}

.site-header[data-open="true"] .nav-toggle__bars span:first-child {
  transform: translateY(3px) rotate(45deg);
}

.site-header[data-open="true"] .nav-toggle__bars span:last-child {
  transform: translateY(-3px) rotate(-45deg);
}

.nav-toggle__label { letter-spacing: .04em; }

/* 7.5 主导航 */
.primary-nav {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.8vw, 28px);
  min-width: 0;
  margin-inline-start: auto;
}

.primary-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.primary-nav__link {
  position: relative;
  display: inline-block;
  padding: 9px 11px;
  border-radius: var(--radius-sm);
  font-size: 14.5px;
  font-weight: 500;
  color: var(--mist);
  transition: color var(--ease-std), background-color var(--ease-std);
}

.primary-nav__link::after {
  content: "";
  position: absolute;
  left: 11px;
  right: 11px;
  bottom: 3px;
  height: 1.5px;
  background: var(--orange);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 200ms cubic-bezier(.4, 0, .2, 1);
}

.primary-nav__link:hover {
  color: var(--white);
  background: rgba(34, 211, 238, .07);
}

.primary-nav__link:hover::after { transform: scaleX(1); }

.primary-nav__link[aria-current="page"] {
  color: var(--cyan);
  background: rgba(34, 211, 238, .10);
}

.primary-nav__link[aria-current="page"]::after {
  background: var(--cyan);
  transform: scaleX(1);
}

.primary-nav__actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ---------- 8. 左侧章节时间轴 ---------- */
.section-rail {
  position: fixed;
  left: calc(env(safe-area-inset-left, 0px) + 14px);
  top: 50%;
  z-index: 70;
  display: none;
  transform: translateY(-50%);
}

.section-rail[hidden] { display: none !important; }

.section-rail__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.section-rail__item { position: relative; }

.section-rail__btn {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 5px 4px;
  border-radius: 4px;
  color: var(--mist);
}

.section-rail__dot {
  flex: none;
  width: 9px;
  height: 2px;
  border-radius: 1px;
  background: var(--line-strong);
  transition: width var(--ease-std), background-color var(--ease-std);
}

.section-rail__label {
  font-family: var(--font-num);
  font-size: 10px;
  letter-spacing: .14em;
  white-space: nowrap;
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity var(--ease-std), transform var(--ease-std), color var(--ease-std);
}

.section-rail__btn:hover .section-rail__dot {
  width: 16px;
  background: var(--cyan);
}

.section-rail__btn:hover .section-rail__label {
  opacity: 1;
  transform: none;
  color: var(--white);
}

.section-rail__btn[aria-current="true"] .section-rail__dot {
  width: 18px;
  background: var(--orange);
}

.section-rail__btn[aria-current="true"] .section-rail__label {
  opacity: 1;
  transform: none;
  color: var(--white);
}

/* ---------- 9. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 120px);
  background: var(--ink-800);
  border-top: 1px solid var(--line);
  overflow: hidden;
}

.footer-beam {
  position: absolute;
  inset: 0 0 auto;
  height: 2px;
  background: linear-gradient(90deg, var(--orange) 0 26%, var(--cyan) 26% 100%);
}

.footer-shell {
  position: relative;
  padding-block: clamp(40px, 6vw, 72px) 0;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 54px);
}

.footer-brand {
  display: grid;
  align-content: start;
  gap: 14px;
  max-width: 36ch;
}

.footer-brand__line {
  font-size: clamp(16px, 1.5vw, 19px);
  line-height: 1.55;
  color: var(--white);
}

.footer-brand__note {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mist);
}

.footer-col__title {
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-num);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.footer-col__list li + li { margin-top: 2px; }

.footer-col__link {
  display: inline-block;
  padding: 6px 0;
  font-size: 14.5px;
  color: var(--mist);
  transition: color var(--ease-std), transform var(--ease-std);
}

.footer-col__link:hover {
  color: var(--white);
  transform: translateX(3px);
}

.footer-contact {
  display: grid;
  gap: 12px;
  margin-top: clamp(32px, 4vw, 56px);
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.footer-contact__item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--mist);
}

.footer-contact__label {
  flex: none;
  font-family: var(--font-num);
  font-size: 10px;
  letter-spacing: .18em;
  color: var(--orange);
}

.footer-contact__value { color: rgba(244, 248, 255, .88); }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  margin-top: clamp(24px, 3vw, 40px);
  padding-block: 22px 26px;
  border-top: 1px solid var(--line);
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .03em;
  line-height: 1.7;
  color: rgba(159, 176, 200, .82);
}

.footer-legal__links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.footer-legal__link {
  color: rgba(159, 176, 200, .82);
  transition: color var(--ease-std);
}

.footer-legal__link:hover { color: var(--cyan); }

.footer-mark {
  display: block;
  margin-top: clamp(12px, 2vw, 24px);
  margin-bottom: -.16em;
  font-family: var(--font-display);
  font-size: clamp(56px, 13vw, 190px);
  line-height: .8;
  letter-spacing: -.04em;
  white-space: nowrap;
  color: rgba(34, 211, 238, .07);
  user-select: none;
  pointer-events: none;
}

/* ---------- 10. 通用组件 ---------- */
.panel {
  position: relative;
  background: var(--ink-700);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: 0 18px 38px -34px #000;
}

.panel--pad { padding: clamp(18px, 2.4vw, 30px); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-family: var(--font-num);
  font-size: 10.5px;
  letter-spacing: .1em;
  color: var(--mist);
}

.tag--cyan {
  border-color: rgba(34, 211, 238, .50);
  background: rgba(34, 211, 238, .08);
  color: var(--cyan);
}

.tag--orange {
  border-color: rgba(255, 107, 44, .55);
  background: rgba(255, 107, 44, .10);
  color: var(--orange);
}

.breadcrumb { margin-bottom: clamp(18px, 2.4vw, 28px); }

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--mist);
}

.breadcrumb__list li + li::before {
  content: "/";
  margin-inline-end: 8px;
  color: var(--line-strong);
}

.breadcrumb__link {
  color: var(--mist);
  transition: color var(--ease-std);
}

.breadcrumb__link:hover { color: var(--cyan); }

.breadcrumb__current { color: var(--white); }

.prose {
  max-width: 72ch;
  font-size: 16.5px;
  line-height: 1.85;
  color: #D6E2F2;
}

.prose > * + * { margin-top: 1em; }

.prose h2 {
  margin-top: 1.8em;
  font-family: var(--font-display);
  font-size: clamp(20px, 2.2vw, 26px);
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--white);
}

.prose h3 {
  margin-top: 1.6em;
  font-size: 18px;
  color: var(--white);
}

.prose a {
  color: var(--cyan);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.prose strong { color: var(--white); }

.prose ul,
.prose ol {
  padding-inline-start: 1.2em;
  list-style: revert;
}

.prose li + li { margin-top: .4em; }

.grid {
  display: grid;
  gap: clamp(14px, 2vw, 26px);
}

.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }

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

.grid--auto { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.empty-state {
  padding: clamp(20px, 3vw, 32px);
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius-md);
  text-align: center;
  font-size: 14.5px;
  color: var(--mist);
}

/* 图片容器基础（页面阶段直接放 img 或占位块） */
.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background:
    linear-gradient(150deg, rgba(34, 211, 238, .10), transparent 55%),
    var(--ink-700);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px rgba(244, 248, 255, .05);
  pointer-events: none;
}

.media-frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide { aspect-ratio: 16 / 7; }
.media-frame--card { aspect-ratio: 16 / 10; }
.media-frame--portrait { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-caption {
  margin-top: 8px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--mist);
}

/* ---------- 11. 响应式 ---------- */
@media (min-width: 860px) {
  .footer-top {
    grid-template-columns: minmax(0, 1.7fr) repeat(3, minmax(0, 1fr));
  }

  .footer-contact {
    grid-template-columns: auto auto minmax(0, 1fr);
    gap: clamp(16px, 3vw, 48px);
    align-items: baseline;
  }
}

@media (min-width: 960px) {
  .grid--split { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); }
}

@media (min-width: 1360px) {
  .section-rail { display: block; }
}

@media (max-width: 1080px) {
  .nav-toggle { display: inline-flex; }

  .header-main__inner {
    flex-wrap: nowrap;
    min-height: 66px;
  }

  .primary-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin-inline-start: 0;
    padding: 10px var(--shell-pad) 22px;
    background: var(--ink-800);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 28px 46px -30px #000;
    max-height: 0;
    overflow: hidden;
    visibility: hidden;
    opacity: 0;
    transition:
      max-height 240ms cubic-bezier(.4, 0, .2, 1),
      opacity 180ms ease,
      visibility 240ms linear;
  }

  .site-header[data-open="true"] .primary-nav {
    max-height: min(74vh, 620px);
    overflow-y: auto;
    visibility: visible;
    opacity: 1;
  }

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

  .primary-nav__link {
    padding: 14px 2px;
    border-bottom: 1px solid var(--line);
    border-radius: 0;
    font-size: 16px;
    color: var(--white);
  }

  .primary-nav__link::after { display: none; }

  .primary-nav__actions {
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    padding-top: 18px;
  }

  .primary-nav__actions .btn { width: 100%; }
}

@media (max-width: 640px) {
  .header-utility__inner {
    font-size: 10.5px;
    letter-spacing: .03em;
  }

  .header-utility__meta { font-size: 10.5px; }

  .media-frame--wide { aspect-ratio: 4 / 3; }

  .footer-legal {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* ---------- 12. 动效降级 ---------- */
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
}