/* ============================================================
   未来太空创新挑战赛 · 第三届 (骏马巡天)
   Static site stylesheet
   ============================================================ */

:root {
  --bg: #050810;
  --bg-soft: #0a1224;
  --panel: rgba(255, 255, 255, 0.04);
  --panel-border: rgba(255, 255, 255, 0.08);
  --text: #eef2ff;
  --text-dim: #aeb8d4;
  --accent: #4da6ff;
  --accent-2: #7cc7ff;
  --gold: #e8c15a;
  --gold-2: #f4d98a;
  --radius: 16px;
  --maxw: 1200px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", -apple-system,
    BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ============ Header ============ */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(5, 8, 16, 0.72);
  border-bottom: 1px solid var(--panel-border);
  transition: background .3s;
}
.site-header.scrolled { background: rgba(5, 8, 16, 0.92); }

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand img { height: 46px; width: 46px; border-radius: 10px; }
.brand .brand-name {
  font-size: 17px; font-weight: 700; letter-spacing: 1px;
}
.brand .brand-en { font-size: 11px; color: var(--text-dim); letter-spacing: .5px; }

.nav { display: flex; align-items: center; gap: 26px; }
.nav a {
  font-size: 15px; color: var(--text-dim);
  padding: 6px 0; position: relative; transition: color .25s;
}
.nav a:hover, .nav a.active { color: var(--text); }
.nav a.active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: 0;
  height: 2px; background: var(--gold); border-radius: 2px;
}
.nav .en-link {
  border: 1px solid var(--panel-border); border-radius: 999px;
  padding: 5px 16px;
}
.nav .en-link:hover { border-color: var(--accent); color: var(--accent-2); }

.nav-toggle {
  display: none;
  background: none; border: none; cursor: pointer;
  width: 40px; height: 40px; position: relative;
}
.nav-toggle span {
  position: absolute; left: 9px; right: 9px; height: 2px;
  background: var(--text); border-radius: 2px; transition: .3s;
}
.nav-toggle span:nth-child(1) { top: 12px; }
.nav-toggle span:nth-child(2) { top: 19px; }
.nav-toggle span:nth-child(3) { top: 26px; }
.nav-toggle.open span:nth-child(1) { top: 19px; transform: rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { top: 19px; transform: rotate(-45deg); }

/* ============ Hero ============ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: flex-end;
  padding: 120px 0 0;
  background-size: cover;
  background-position: center;
}
.hero::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg,
    rgba(5,8,16,.25) 0%, rgba(5,8,16,.45) 45%, rgba(5,8,16,.92) 100%);
  z-index: 1;
}
.hero .wrap { position: relative; z-index: 2; width: 100%; }

.hero-title-block { text-align: center; }
.hero-edition {
  display: inline-block;
  font-size: 15px; letter-spacing: 6px;
  color: var(--gold); font-weight: 600;
  border: 1px solid rgba(232,193,90,.5); border-radius: 999px;
  padding: 6px 22px; margin-bottom: 18px;
}
.hero-title {
  font-size: clamp(38px, 7vw, 72px);
  font-weight: 800; letter-spacing: 4px; line-height: 1.15;
}
.hero-sub {
  margin-top: 14px; font-size: clamp(13px, 2vw, 19px);
  color: var(--accent-2); letter-spacing: 3px; text-transform: uppercase;
}
.hero-theme {
  margin-top: 34px; font-size: clamp(24px, 4vw, 40px);
  font-weight: 700; letter-spacing: 8px; color: #fff;
}
.hero-theme .cn { color: var(--gold-2); }
.hero-theme-en { margin-top: 8px; font-size: 15px; letter-spacing: 4px; color: var(--text-dim); }

/* ============ Stats (报名情况) ============ */
.stats-section {
  position: relative; z-index: 2;
  margin-top: -60px;
}
.stats-panel {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  backdrop-filter: blur(10px);
  padding: 34px 20px;
}
.stats-title {
  text-align: center; font-size: 15px; color: var(--text-dim);
  letter-spacing: 4px; margin-bottom: 22px;
}
.stats-grid {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 16px 34px;
}
.stat-item { text-align: center; min-width: 90px; }
.stat-num {
  font-size: 40px; font-weight: 800; color: var(--gold-2);
  font-variant-numeric: tabular-nums; letter-spacing: 1px;
  min-height: 56px; display: flex; align-items: center; justify-content: center;
}
.stat-label { font-size: 14px; color: var(--text); margin-top: 4px; }
.stat-sep { align-self: center; width: 1px; height: 54px; background: var(--panel-border); }

.cta-row { text-align: center; margin-top: 26px; }
.btn {
  display: inline-block;
  font-size: 16px; font-weight: 700; letter-spacing: 2px;
  color: #08111f;
  background: linear-gradient(135deg, var(--gold) 0%, var(--gold-2) 100%);
  padding: 13px 46px; border-radius: 999px;
  box-shadow: 0 8px 24px rgba(232,193,90,.28);
  transition: transform .25s, box-shadow .25s;
}
.btn:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(232,193,90,.4); }
.btn.ghost {
  background: transparent; color: var(--text);
  border: 1px solid var(--panel-border); box-shadow: none;
}
.btn.ghost:hover { border-color: var(--accent); color: var(--accent-2); }

/* ============ Sections ============ */
.section { padding: 88px 0; }
.section.alt { background: var(--bg-soft); }

.section-head { text-align: center; margin-bottom: 48px; }
.section-head .en {
  font-size: 13px; letter-spacing: 5px; text-transform: uppercase;
  color: var(--accent); margin-bottom: 10px;
}
.section-head h2 {
  font-size: clamp(26px, 4vw, 40px); font-weight: 800; letter-spacing: 3px;
}
.section-head .rule {
  width: 56px; height: 3px; margin: 18px auto 0;
  background: linear-gradient(90deg, var(--gold), transparent);
  border-radius: 2px;
}

/* About split */
.about-split {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center;
}
.about-split .lead { font-size: 16px; color: var(--text-dim); }
.about-split p { margin-bottom: 16px; }
.about-split .highlight { color: var(--gold-2); font-weight: 600; }

/* Cards grid */
.cards { display: grid; gap: 24px; }
.cards.cols-2 { grid-template-columns: repeat(2, 1fr); }
.cards.cols-3 { grid-template-columns: repeat(3, 1fr); }

.card {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  padding: 28px;
  transition: transform .3s, border-color .3s;
}
.card:hover { transform: translateY(-4px); border-color: rgba(77,166,255,.4); }
.card .card-icon { font-size: 34px; margin-bottom: 14px; }
.card h3 { font-size: 21px; font-weight: 700; margin-bottom: 12px; letter-spacing: 1px; }
.card h3 .en { display: block; font-size: 12px; color: var(--accent); letter-spacing: 2px; margin-top: 2px; }
.card p { font-size: 14.5px; color: var(--text-dim); }
.card .tag {
  display: inline-block; font-size: 12px; color: var(--gold);
  border: 1px solid rgba(232,193,90,.4); border-radius: 999px;
  padding: 2px 12px; margin-bottom: 12px;
}
.card img.cover { border-radius: 12px; margin-bottom: 16px; width: 100%; object-fit: cover; }

/* Media split card */
.media-card {
  display: grid; grid-template-columns: 1fr 1fr; gap: 32px; align-items: center;
  background: var(--panel); border: 1px solid var(--panel-border);
  border-radius: var(--radius); padding: 24px;
}
.media-card img { border-radius: 12px; }
.media-card h3 { font-size: 22px; margin-bottom: 12px; }
.media-card p { color: var(--text-dim); font-size: 14.5px; }

/* List styles */
.list-check li {
  position: relative; padding-left: 26px; margin-bottom: 12px;
  color: var(--text-dim); font-size: 15px;
}
.list-check li::before {
  content: "◆"; position: absolute; left: 0; top: 0;
  color: var(--gold); font-size: 12px;
}

/* ============ Partners ============ */
.partners-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px;
}
.partner {
  background: #fff; border-radius: 12px; padding: 18px;
  display: flex; align-items: center; justify-content: center;
  min-height: 96px;
}
.partner img { max-height: 58px; width: auto; }

/* ============ Content page hero ============ */
.page-hero {
  padding: 150px 0 70px;
  text-align: center;
  background:
    radial-gradient(60% 50% at 50% 0%, rgba(77,166,255,.12), transparent 70%),
    var(--bg);
  border-bottom: 1px solid var(--panel-border);
}
.page-hero .en { font-size: 13px; letter-spacing: 5px; text-transform: uppercase; color: var(--accent); }
.page-hero h1 { font-size: clamp(30px, 5vw, 46px); font-weight: 800; letter-spacing: 3px; margin-top: 10px; }

/* ============ Org table ============ */
.org-table { width: 100%; border-collapse: collapse; }
.org-table th, .org-table td {
  border: 1px solid var(--panel-border); padding: 16px 20px; text-align: left;
}
.org-table th {
  width: 170px; color: var(--gold-2); font-weight: 600;
  background: var(--panel); white-space: nowrap;
}
.org-table td { color: var(--text-dim); }

/* ============ Schedule timeline ============ */
.timeline { display: grid; gap: 20px; }
.timeline-item {
  display: flex; gap: 22px; background: var(--panel);
  border: 1px solid var(--panel-border); border-radius: var(--radius); padding: 24px;
}
.timeline-item .date {
  flex: 0 0 auto; min-width: 150px;
  font-size: 17px; font-weight: 700; color: var(--gold-2); letter-spacing: 1px;
}
.timeline-item .desc { color: var(--text-dim); font-size: 15px; }
.timeline-item .desc b { color: var(--text); }

/* ============ Award tiers ============ */
.tiers { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.tier {
  text-align: center; padding: 34px 22px;
  background: var(--panel); border: 1px solid var(--panel-border); border-radius: var(--radius);
}
.tier .rank { font-size: 22px; font-weight: 800; letter-spacing: 2px; color: var(--gold-2); }
.tier .prize { font-size: 26px; font-weight: 800; color: #fff; margin: 10px 0 6px; }
.tier .note { font-size: 13px; color: var(--text-dim); }

/* ============ Statement ============ */
.statement { max-width: 860px; margin: 0 auto; }
.statement .rule-card {
  background: var(--panel); border: 1px solid var(--panel-border);
  border-radius: var(--radius); padding: 30px 34px; margin-bottom: 20px;
}
.statement h3 { font-size: 19px; margin-bottom: 16px; color: var(--gold-2); letter-spacing: 1px; }
.statement ol, .statement ul { padding-left: 22px; }
.statement li { margin-bottom: 12px; color: var(--text-dim); font-size: 15px; }
.statement ol { list-style: decimal; }
.statement ol li::marker { color: var(--gold); }

/* ============ Footer ============ */
.site-footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--panel-border);
  padding: 56px 0 0;
}
.footer-grid {
  display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 40px;
  padding-bottom: 40px;
}
.footer-brand { display: flex; align-items: center; gap: 14px; }
.footer-brand img { height: 56px; width: 56px; border-radius: 12px; }
.footer-brand .name { font-size: 18px; font-weight: 700; }
.footer-brand .en { font-size: 12px; color: var(--text-dim); letter-spacing: .5px; }
.footer-contact p { color: var(--text-dim); font-size: 14px; margin-bottom: 8px; }
.footer-qr { text-align: center; }
.footer-qr img { width: 120px; height: 120px; margin: 0 auto; border-radius: 8px; }
.footer-qr .label { font-size: 13px; color: var(--text-dim); margin-top: 10px; }
.footer-tagline {
  text-align: center; padding: 22px 0; font-size: 18px; letter-spacing: 4px;
  color: var(--gold-2); border-top: 1px solid var(--panel-border);
}
.footer-copy {
  text-align: center; padding: 18px 0; font-size: 12.5px; color: #667;
  border-top: 1px solid var(--panel-border);
}
.footer-copy a { color: #667; }

/* ============ Reveal animation ============ */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s, transform .7s; }
.reveal.visible { opacity: 1; transform: none; }

/* ============ Responsive ============ */
@media (max-width: 960px) {
  .about-split, .media-card { grid-template-columns: 1fr; }
  .cards.cols-2, .cards.cols-3 { grid-template-columns: 1fr; }
  .tiers { grid-template-columns: 1fr; }
  .partners-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .org-table th { width: 120px; }
}

@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .nav {
    position: absolute; top: 72px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: rgba(5,8,16,.98); border-bottom: 1px solid var(--panel-border);
    padding: 8px 24px 20px; display: none;
  }
  .nav.open { display: flex; }
  .nav a { padding: 14px 0; border-bottom: 1px solid var(--panel-border); }
  .nav a.en-link { border: none; margin-top: 12px; text-align: center; }
  .stats-grid { gap: 12px 20px; }
  .stat-num { font-size: 32px; }
  .stat-sep { display: none; }
  .timeline-item { flex-direction: column; gap: 8px; }
  .partners-grid { grid-template-columns: repeat(2, 1fr); }
  .brand .brand-name { display: none; }
}