:root {
  --bg: #0a0b0d;
  --bg-soft: #101216;
  --panel: #15181d;
  --panel-2: #1b1f26;
  --line: rgba(255, 255, 255, 0.09);
  --line-strong: rgba(255, 255, 255, 0.18);
  --text: #f2f3f5;
  --muted: #9aa2ad;
  --accent: #e10600;
  --accent-2: #ff4d3d;
  --accent-soft: rgba(225, 6, 0, 0.14);
  --radius: 14px;
  --max: 1180px;
  --font: "PingFang SC", "Microsoft YaHei", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* 保证 hidden 属性始终生效（否则会被下面的 display 声明覆盖） */
[hidden] { display: none !important; }

.grid-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.028) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.028) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse at 50% 0%, #000 30%, transparent 78%);
}

/* ---------------- 顶部导航 ---------------- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 16px clamp(16px, 4vw, 48px);
  transition: background 0.25s ease, backdrop-filter 0.25s ease, border-color 0.25s ease, padding 0.25s ease;
  border-bottom: 1px solid transparent;
}

.site-header.scrolled {
  background: rgba(10, 11, 13, 0.86);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
  padding-top: 10px;
  padding-bottom: 10px;
}

.brand { display: flex; align-items: center; gap: 12px; }

.brand-mark {
  width: 40px;
  height: 40px;
  color: var(--accent);
  filter: drop-shadow(0 0 14px rgba(225, 6, 0, 0.55));
  flex: none;
}
.brand-mark svg { width: 100%; height: 100%; }

.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong { font-size: 17px; letter-spacing: 0.06em; }
.brand-text small { font-size: 10px; color: var(--muted); letter-spacing: 0.16em; }

.site-nav { display: flex; gap: 26px; margin-left: auto; font-size: 14.5px; }
.site-nav a { color: #cdd2d9; position: relative; padding: 4px 0; transition: color 0.2s; }
.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  height: 2px;
  width: 0;
  background: var(--accent);
  transition: width 0.25s ease;
}
.site-nav a:hover { color: #fff; }
.site-nav a:hover::after { width: 100%; }

.header-actions { display: flex; align-items: center; gap: 10px; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  padding: 8px;
  cursor: pointer;
}
.nav-toggle span { width: 22px; height: 2px; background: #fff; transition: 0.25s; }

/* ---------------- 按钮 ---------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 4px;
  border: 1px solid transparent;
  font-size: 14.5px;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.22s ease, background 0.22s ease, color 0.22s ease;
  font-family: inherit;
}
.btn:hover { transform: translateY(-2px); }

.btn-primary { background: linear-gradient(135deg, var(--accent-2), var(--accent)); color: #fff; box-shadow: 0 10px 26px rgba(225, 6, 0, 0.3); }
.btn-primary:hover { box-shadow: 0 14px 34px rgba(225, 6, 0, 0.44); }

.btn-outline { border-color: var(--line-strong); color: #fff; background: rgba(255, 255, 255, 0.03); }
.btn-outline:hover { border-color: #fff; background: rgba(255, 255, 255, 0.1); }

.btn-ghost { border-color: var(--line); color: #d6dae0; background: rgba(255, 255, 255, 0.04); }
.btn-ghost:hover { color: #fff; border-color: var(--line-strong); }

.btn-sm { padding: 8px 16px; font-size: 13px; }
.btn[disabled] { opacity: 0.6; cursor: not-allowed; transform: none; }

/* ---------------- Hero ---------------- */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 140px clamp(16px, 5vw, 64px) 100px;
  overflow: hidden;
  isolation: isolate;
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: -2;
  background: #06070a center/cover no-repeat;
  transform: scale(1.04);
  filter: saturate(1.06);
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(ellipse at 78% 30%, rgba(225, 6, 0, 0.28), transparent 58%),
    linear-gradient(100deg, rgba(6, 7, 10, 0.96) 8%, rgba(6, 7, 10, 0.72) 42%, rgba(6, 7, 10, 0.42) 100%);
}

.hero-inner { max-width: 760px; position: relative; }

.kicker {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.42em;
  color: var(--accent-2);
  margin: 0 0 20px;
  text-transform: uppercase;
}

.hero-title {
  font-size: clamp(32px, 5.2vw, 62px);
  line-height: 1.14;
  margin: 0 0 20px;
  font-weight: 800;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

.hero-sub { font-size: clamp(15px, 1.5vw, 18px); color: #c8cdd4; max-width: 620px; margin: 0 0 32px; }

.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }

.hero-slogan {
  margin: 40px 0 0;
  font-size: 15px;
  letter-spacing: 0.24em;
  color: var(--muted);
  padding-left: 18px;
  border-left: 3px solid var(--accent);
}

.speed-stripes { position: absolute; right: -60px; top: 22%; display: flex; gap: 16px; transform: skewX(-18deg); z-index: -1; opacity: 0.5; }
.speed-stripes i { display: block; width: 6px; height: 320px; background: linear-gradient(180deg, transparent, var(--accent), transparent); }
.speed-stripes i:nth-child(2) { height: 420px; opacity: 0.6; }
.speed-stripes i:nth-child(3) { height: 240px; opacity: 0.35; }

/* ---------------- 数据条 ---------------- */

.stats-bar {
  position: relative;
  z-index: 2;
  margin-top: -60px;
  padding: 0 clamp(16px, 5vw, 64px);
}

.stats-grid {
  max-width: var(--max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  backdrop-filter: blur(10px);
}

.stat {
  background: rgba(16, 18, 22, 0.92);
  padding: 26px 24px;
  position: relative;
}
.stat::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 42px;
  height: 3px;
  background: var(--accent);
}
.stat strong { display: block; font-size: clamp(24px, 3vw, 36px); font-family: var(--mono); letter-spacing: -0.02em; }
.stat span { font-size: 13px; color: var(--muted); letter-spacing: 0.1em; }

/* ---------------- 区块 ---------------- */

.section {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(72px, 9vw, 120px) clamp(16px, 5vw, 32px);
}

.section-alt::before {
  content: "";
  position: absolute;
  inset: 0 calc(50% - 50vw);
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  z-index: -1;
}

.section-head { margin-bottom: 46px; position: relative; padding-left: 22px; }
.section-head::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 40px;
  width: 3px;
  background: linear-gradient(180deg, var(--accent), transparent);
}
.section-index { font-family: var(--mono); font-size: 12px; color: var(--accent); letter-spacing: 0.3em; }
.section-head h2 { font-size: clamp(24px, 3.4vw, 38px); margin: 6px 0 4px; letter-spacing: -0.01em; }
.section-note { margin: 0; font-family: var(--mono); font-size: 11px; letter-spacing: 0.34em; color: var(--muted); }

/* ---------------- 关于 ---------------- */

.about-layout { display: grid; grid-template-columns: 1.05fr 1fr; gap: 48px; align-items: start; }
.about-copy p { color: #c4cad2; margin: 0 0 18px; font-size: 15.5px; }
.about-copy p:first-child { font-size: 17px; color: #e7eaee; }

.highlight-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.highlight {
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 20px;
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}
.highlight:hover { transform: translateY(-4px); background: var(--panel-2); border-color: var(--line-strong); border-left-color: var(--accent); }
.highlight h4 { margin: 0 0 8px; font-size: 16px; letter-spacing: 0.04em; }
.highlight p { margin: 0; font-size: 13.5px; color: var(--muted); line-height: 1.65; }

/* ---------------- 技术小组 ---------------- */

.division-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 16px; }
.division {
  position: relative;
  background: linear-gradient(160deg, var(--panel), rgba(21, 24, 29, 0.45));
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 24px 22px 26px;
  overflow: hidden;
  transition: transform 0.22s ease, border-color 0.22s ease;
}
.division::after {
  content: "";
  position: absolute;
  right: -30px;
  bottom: -30px;
  width: 90px;
  height: 90px;
  background: var(--accent-soft);
  transform: rotate(45deg);
  transition: background 0.25s ease;
}
.division:hover { transform: translateY(-5px); border-color: rgba(225, 6, 0, 0.5); }
.division:hover::after { background: rgba(225, 6, 0, 0.3); }
.division .idx { font-family: var(--mono); font-size: 12px; color: var(--accent); letter-spacing: 0.2em; }
.division h3 { margin: 10px 0 8px; font-size: 17px; }
.division p { margin: 0; font-size: 13.5px; color: var(--muted); position: relative; z-index: 1; }

/* ---------------- 参数 ---------------- */

.specs-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(18px, 3vw, 34px);
}

.specs-table { width: 100%; border-collapse: collapse; }
.specs-table tr { border-bottom: 1px solid var(--line); }
.specs-table tr:last-child { border-bottom: 0; }
.specs-table th,
.specs-table td { padding: 15px 12px; text-align: left; font-size: 15px; font-weight: 400; }
.specs-table th { color: var(--muted); width: 40%; letter-spacing: 0.06em; }
.specs-table td { font-family: var(--mono); color: #fff; font-size: 14.5px; }
.specs-table tr:hover td, .specs-table tr:hover th { background: rgba(255, 255, 255, 0.025); }
.specs-note { margin: 20px 0 0; font-size: 12.5px; color: var(--muted); }

/* ---------------- 新闻 ---------------- */

.news-list { display: flex; flex-direction: column; gap: 14px; }
.news-item {
  display: grid;
  grid-template-columns: 132px 1fr auto;
  gap: 22px;
  align-items: center;
  padding: 22px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 10px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.news-item:hover { transform: translateX(5px); border-color: rgba(225, 6, 0, 0.45); }
.news-date { font-family: var(--mono); font-size: 13px; color: var(--accent-2); letter-spacing: 0.08em; }
.news-body h3 { margin: 0 0 6px; font-size: 17px; }
.news-body p { margin: 0; font-size: 14px; color: var(--muted); }
.news-thumb { width: 108px; height: 68px; border-radius: 6px; object-fit: cover; border: 1px solid var(--line); }

/* ---------------- 图集 ---------------- */

.gallery-filters { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 22px; }
.chip {
  padding: 7px 16px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
  color: #c9ced6;
  font-size: 13px;
  cursor: pointer;
  transition: 0.2s;
  font-family: inherit;
}
.chip:hover { border-color: var(--line-strong); color: #fff; }
.chip.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.gallery-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 14px; }

.photo-card {
  position: relative;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--panel);
  cursor: zoom-in;
  aspect-ratio: 4 / 3;
}
.photo-card img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.photo-card:hover img { transform: scale(1.07); }
.photo-card figcaption {
  position: absolute;
  inset: auto 0 0 0;
  padding: 30px 14px 12px;
  font-size: 13.5px;
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.86));
  opacity: 0;
  transform: translateY(8px);
  transition: 0.28s ease;
}
.photo-card:hover figcaption { opacity: 1; transform: none; }
.photo-card .tag {
  position: absolute;
  top: 10px;
  left: 10px;
  font-size: 11px;
  font-family: var(--mono);
  background: rgba(225, 6, 0, 0.9);
  padding: 3px 9px;
  border-radius: 3px;
  letter-spacing: 0.06em;
}

.empty-hint { color: var(--muted); font-size: 14px; }

/* ---------------- 联系 ---------------- */

.contact-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.contact-intro { color: #c4cad2; font-size: 15.5px; margin: 0 0 24px; }
.contact-list { list-style: none; margin: 0 0 24px; padding: 0; }
.contact-list li { display: flex; gap: 14px; padding: 13px 0; border-bottom: 1px solid var(--line); font-size: 14.5px; }
.contact-list .label { color: var(--muted); min-width: 68px; letter-spacing: 0.08em; font-size: 13px; padding-top: 2px; }
.contact-list .value { color: #eef0f3; word-break: break-all; }
.contact-sponsors { font-size: 13px; color: var(--muted); border-left: 3px solid var(--accent); padding-left: 14px; margin: 0; }

.contact-form {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
}
.contact-form h3 { margin: 0 0 20px; font-size: 18px; letter-spacing: 0.04em; }
.contact-form label { display: block; margin-bottom: 16px; font-size: 13.5px; color: var(--muted); letter-spacing: 0.04em; }
.contact-form .req { color: var(--accent); }
.contact-form input,
.contact-form textarea {
  width: 100%;
  margin-top: 7px;
  padding: 11px 13px;
  background: #0d0f13;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--text);
  font-family: inherit;
  font-size: 14.5px;
  resize: vertical;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.contact-form input:focus,
.contact-form textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.form-status { font-size: 13.5px; margin: 12px 0 0; min-height: 20px; }
.form-status.ok { color: #45d07a; }
.form-status.err { color: var(--accent-2); }

/* ---------------- 页脚 ---------------- */

.site-footer {
  border-top: 1px solid var(--line);
  background: #07080a;
  padding: 48px clamp(16px, 5vw, 64px) 28px;
  position: relative;
  z-index: 1;
}
.footer-inner { max-width: var(--max); margin: 0 auto; display: flex; justify-content: space-between; gap: 30px; flex-wrap: wrap; }
.footer-inner strong { font-size: 16px; letter-spacing: 0.05em; }
.footer-note { color: var(--muted); font-size: 13.5px; margin: 8px 0 0; letter-spacing: 0.12em; }
.footer-links { display: flex; gap: 22px; flex-wrap: wrap; font-size: 14px; color: #c0c6ce; }
.footer-links a:hover { color: var(--accent-2); }
.copyright { max-width: var(--max); margin: 34px auto 0; font-size: 12.5px; color: #6d747d; border-top: 1px solid var(--line); padding-top: 18px; }

/* ---------------- 灯箱 ---------------- */

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 90;
  background: rgba(4, 5, 7, 0.95);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px;
  backdrop-filter: blur(6px);
}
.lightbox figure { margin: 0; max-width: 92vw; max-height: 88vh; text-align: center; }
.lightbox img { max-width: 92vw; max-height: 80vh; border-radius: 8px; margin: 0 auto; }
.lightbox figcaption { margin-top: 14px; font-size: 14px; color: #cfd4da; }
.lightbox-close {
  position: absolute;
  top: 22px;
  right: 26px;
  font-size: 32px;
  line-height: 1;
  background: none;
  border: 0;
  color: #fff;
  cursor: pointer;
  opacity: 0.75;
}
.lightbox-close:hover { opacity: 1; }
.lightbox-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 42px;
  line-height: 1;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--line);
  color: #fff;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  cursor: pointer;
  transition: 0.2s;
}
.lightbox-nav:hover { background: var(--accent); border-color: var(--accent); }
.lightbox-nav.prev { left: 26px; }
.lightbox-nav.next { right: 26px; }

/* ---------------- 滚动动画 ---------------- */

.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------------- 响应式 ---------------- */

@media (max-width: 980px) {
  .about-layout, .contact-layout { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .news-item { grid-template-columns: 1fr; gap: 12px; }
  .news-thumb { width: 100%; height: 140px; }
}

@media (max-width: 760px) {
  .nav-toggle { display: flex; }
  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(10, 11, 13, 0.98);
    border-bottom: 1px solid var(--line);
    padding: 8px 20px 18px;
    display: none;
  }
  .site-nav.open { display: flex; }
  .site-nav a { padding: 12px 0; border-bottom: 1px solid var(--line); }
  .highlight-grid { grid-template-columns: 1fr; }
  .hero { min-height: 88vh; padding-top: 120px; }
  .stats-bar { margin-top: -30px; }
  .hero-slogan { letter-spacing: 0.12em; }
  .lightbox-nav { width: 42px; height: 42px; font-size: 32px; }
  .lightbox-nav.prev { left: 8px; }
  .lightbox-nav.next { right: 8px; }
}