/* ==========================================================================
   波胆网官网 — 五大联赛足球战术AI大模型
   Static stylesheet. No frameworks, no remote fonts, no build step.
   ========================================================================== */

:root {
  --bg: #f6f4ee;
  --bg-alt: #efece2;
  --panel: #ffffff;
  --panel-soft: #fbfaf6;
  --navy: #10203a;
  --navy-2: #1c355c;
  --navy-3: #274a7d;
  --pitch: #1f7a4d;
  --pitch-2: #2fa968;
  --pitch-soft: #e4f3ea;
  --cyan: #0e8fa3;
  --cyan-soft: #e2f4f6;
  --orange: #d9722c;
  --orange-soft: #fbe9da;
  --graphite: #3a3d42;
  --ink: #1a1d22;
  --muted: #5c6270;
  --muted-2: #7b8190;
  --line: #e2ded2;
  --line-soft: #ece8dc;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 8px 24px rgba(16, 32, 58, 0.08);
  --shadow-sm: 0 2px 10px rgba(16, 32, 58, 0.06);
  --maxw: 1180px;
  --font-base: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --font-serif: "Songti SC", "STSong", "Noto Serif SC", Georgia, serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; overflow-x: hidden; max-width: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-base);
  line-height: 1.75;
  font-size: 16px;
  overflow-x: hidden;
  -webkit-text-size-adjust: 100%;
}
img, svg { max-width: 100%; height: auto; display: block; }
a { color: var(--navy-3); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { font-family: var(--font-serif); color: var(--navy); line-height: 1.4; margin: 0 0 .6em; font-weight: 700; }
p { margin: 0 0 1em; }
ul, ol { padding-left: 1.4em; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
section { padding: 56px 0; }
.section-alt { background: var(--bg-alt); }
.section-panel { background: var(--panel); }

/* ---------- Skip link ---------- */
.skip-link {
  position: absolute; left: -999px; top: 0; background: var(--navy); color: #fff;
  padding: 10px 16px; z-index: 999; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(246, 244, 238, 0.96);
  backdrop-filter: saturate(140%) blur(6px);
  border-bottom: 1px solid var(--line);
}
.nav-wrap { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--font-serif); font-weight: 700; font-size: 21px; color: var(--navy); }
.brand:hover { text-decoration: none; }
.brand-mark { width: 34px; height: 34px; flex-shrink: 0; }
.brand-sub { font-size: 12px; color: var(--muted); font-weight: 400; margin-left: 4px; font-family: var(--font-base); }
.main-nav { display: flex; gap: 2px; }
.main-nav a {
  color: var(--graphite); font-size: 15px; padding: 10px 14px; border-radius: 8px; font-weight: 600;
}
.main-nav a:hover { background: var(--pitch-soft); color: var(--pitch); text-decoration: none; }
.main-nav a.active { color: var(--pitch); background: var(--pitch-soft); }
.nav-toggle {
  display: none; width: 40px; height: 40px; border-radius: 8px; border: 1px solid var(--line);
  background: var(--panel); position: relative; cursor: pointer;
}
.nav-toggle span, .nav-toggle::before, .nav-toggle::after {
  content: ""; position: absolute; left: 8px; right: 8px; height: 2px; background: var(--navy); transition: transform .2s, opacity .2s;
}
.nav-toggle::before { top: 13px; }
.nav-toggle span { top: 19px; }
.nav-toggle::after { top: 25px; }
.nav-toggle[aria-expanded="true"]::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"]::after { transform: translateY(-6px) rotate(-45deg); }
.nav-toggle[aria-expanded="true"] span { opacity: 0; }

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(160deg, var(--navy) 0%, var(--navy-2) 58%, var(--navy-3) 100%);
  color: #eef2f6; padding: 64px 0 52px; position: relative; overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; inset: 0; opacity: .10; pointer-events: none;
  background-image: repeating-linear-gradient(0deg, transparent 0 38px, rgba(255,255,255,.5) 38px 39px);
}
.hero .container { position: relative; z-index: 1; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 8px; font-size: 13px; letter-spacing: .04em;
  color: var(--pitch-2); background: rgba(47,169,104,0.14); border: 1px solid rgba(47,169,104,0.35);
  padding: 5px 12px; border-radius: 999px; margin-bottom: 18px; font-weight: 600;
}
.hero h1 { color: #fff; font-size: clamp(26px, 4vw, 40px); max-width: 900px; margin-bottom: 20px; }
.hero-lead { max-width: 780px; color: #cdd7e6; font-size: 17px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
.hero-tags span {
  font-size: 13px; color: #dfe8f2; border: 1px solid rgba(255,255,255,0.2); background: rgba(255,255,255,0.06);
  padding: 5px 12px; border-radius: 999px;
}
.hero-cta { display: flex; gap: 12px; margin-top: 28px; flex-wrap: wrap; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-block; padding: 12px 22px; border-radius: 10px; font-weight: 700; font-size: 15px;
  border: 1px solid transparent; cursor: pointer;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--pitch); color: #fff; }
.btn-primary:hover { background: var(--pitch-2); }
.btn-ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,0.4); }
.btn-ghost:hover { background: rgba(255,255,255,0.08); }
.btn-outline { background: transparent; color: var(--navy); border-color: var(--navy); }
.btn-outline:hover { background: var(--navy); color: #fff; }

/* ---------- Section headings ---------- */
.section-head { max-width: 760px; margin: 0 auto 34px; text-align: left; }
.section-head.center { text-align: center; margin-left: auto; margin-right: auto; }
.section-kicker { color: var(--pitch); font-weight: 700; font-size: 13px; letter-spacing: .06em; text-transform: uppercase; margin-bottom: 8px; display: block; }
.section-head h2 { font-size: clamp(22px, 3vw, 30px); margin-bottom: 10px; }
.section-head p { color: var(--muted); font-size: 15.5px; }

/* ---------- Trend grid (2026 frontiers) ---------- */
.trend-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 18px; }
.trend-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px;
  box-shadow: var(--shadow-sm);
}
.trend-card .tag { display: inline-block; font-size: 12px; color: var(--cyan); background: var(--cyan-soft); padding: 3px 10px; border-radius: 999px; font-weight: 700; margin-bottom: 10px; }
.trend-card h3 { font-size: 16.5px; margin-bottom: 8px; }
.trend-card p { color: var(--muted); font-size: 14.5px; margin-bottom: 0; }

/* ---------- News ticker ---------- */
.news-list { display: grid; gap: 14px; }
.news-item {
  display: grid; grid-template-columns: 90px 1fr; gap: 16px; background: var(--panel);
  border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 14px 16px;
}
.news-item .news-cat { color: var(--pitch); font-weight: 700; font-size: 12.5px; }
.news-item p { margin: 0; color: var(--graphite); font-size: 14.5px; }

/* ---------- Diagram frame ---------- */
.diagram-frame {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px; box-shadow: var(--shadow-sm); overflow-x: auto;
}
.diagram-frame svg { margin: 0 auto; }
.diagram-caption { text-align: center; color: var(--muted); font-size: 13.5px; margin-top: 12px; }

/* ---------- Long-form article blocks ---------- */
.article-block {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px clamp(18px, 4vw, 38px); margin-bottom: 26px; box-shadow: var(--shadow-sm);
  scroll-margin-top: 84px;
}
.article-meta { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin-bottom: 14px; }
.article-meta .pill {
  font-size: 12px; font-weight: 700; padding: 4px 11px; border-radius: 999px;
}
.pill-formation { background: var(--pitch-soft); color: var(--pitch); }
.pill-press { background: var(--orange-soft); color: var(--orange); }
.pill-space { background: var(--cyan-soft); color: var(--cyan); }
.pill-defence { background: #eef0fb; color: #4b4fa3; }
.pill-transition { background: #fdeef0; color: #b3395a; }
.pill-setpiece { background: #f1f3d8; color: #7a7326; }
.pill-coach { background: #e9e4f7; color: #6a4bb0; }
.pill-app { background: var(--pitch-soft); color: var(--pitch); }
.article-index { color: var(--muted-2); font-size: 12.5px; }
.article-block h3 { font-size: clamp(19px, 2.6vw, 24px); margin-bottom: 16px; }
.article-block h4 { font-size: 16px; color: var(--navy-3); margin: 22px 0 10px; }
.article-body p { color: var(--graphite); font-size: 15.5px; }
.article-body strong { color: var(--navy); }
.callout {
  background: var(--panel-soft); border-left: 3px solid var(--pitch); padding: 14px 18px; border-radius: 0 8px 8px 0;
  margin: 18px 0; font-size: 14.5px; color: var(--graphite);
}
.callout.warn { border-left-color: var(--orange); }
.callout.info { border-left-color: var(--cyan); }
.article-links { margin-top: 18px; padding-top: 16px; border-top: 1px dashed var(--line); font-size: 14px; }
.article-links strong { color: var(--navy); font-size: 13.5px; }
.article-links a { margin-right: 14px; }

/* ---------- Timeline (dynamic formation) ---------- */
.phase-timeline { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; margin: 18px 0; }
.phase-step { background: var(--panel-soft); border: 1px solid var(--line); border-radius: 10px; padding: 12px 8px; text-align: center; }
.phase-step .t { font-size: 11.5px; color: var(--muted-2); }
.phase-step .f { font-family: var(--font-serif); font-weight: 700; color: var(--navy); font-size: 16px; margin: 4px 0; }
.phase-step .d { font-size: 12px; color: var(--muted); }
@media (max-width: 640px) { .phase-timeline { grid-template-columns: repeat(2, 1fr); } }

/* ---------- Observation / short essay cards ---------- */
.observe-grid { display: grid; gap: 20px; }
.observe-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px 26px;
  box-shadow: var(--shadow-sm); scroll-margin-top: 84px;
}
.observe-card h3 { font-size: 17.5px; }
.observe-card p { color: var(--graphite); font-size: 15px; }

/* ---------- Cluster / summary rollup ---------- */
.cluster { margin-bottom: 40px; scroll-margin-top: 84px; }
.cluster-head { display: flex; align-items: baseline; justify-content: space-between; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; border-bottom: 2px solid var(--navy); padding-bottom: 10px; }
.cluster-head h3 { margin: 0; font-size: 20px; }
.cluster-head .more { font-size: 13.5px; font-weight: 700; }
.summary-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 16px; }
.summary-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 18px 20px;
  display: flex; flex-direction: column; gap: 8px;
}
.summary-card .cat { font-size: 12px; font-weight: 700; color: var(--pitch); }
.summary-card h4 { margin: 0; font-size: 15.5px; color: var(--navy); line-height: 1.5; }
.summary-card p { font-size: 13.8px; color: var(--muted); margin: 0; }
.summary-card .rl { font-size: 13px; font-weight: 700; margin-top: auto; }

/* ---------- Tabs ---------- */
.tabs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 18px; }
.tab-btn {
  border: 1px solid var(--line); background: var(--panel); color: var(--graphite); font-weight: 700;
  padding: 9px 16px; border-radius: 999px; cursor: pointer; font-size: 14px; font-family: var(--font-base);
}
.tab-btn.active { background: var(--navy); color: #fff; border-color: var(--navy); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* ---------- Feature grid (app functions) ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 18px; }
.feature-card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; box-shadow: var(--shadow-sm); }
.feature-card .num { font-family: var(--font-serif); font-size: 26px; color: var(--pitch); font-weight: 700; }
.feature-card h3 { font-size: 16px; margin: 6px 0 8px; }
.feature-card p { font-size: 14px; color: var(--muted); margin: 0; }

/* ---------- FAQ ---------- */
.faq-list { border-top: 1px solid var(--line); }
.faq-item { border-bottom: 1px solid var(--line); }
.faq-q {
  width: 100%; text-align: left; background: none; border: none; padding: 18px 4px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center; gap: 14px;
  font-size: 16px; font-weight: 700; color: var(--navy); font-family: var(--font-base);
}
.faq-q .ic { flex-shrink: 0; width: 22px; height: 22px; position: relative; }
.faq-q .ic::before, .faq-q .ic::after { content: ""; position: absolute; background: var(--pitch); transition: transform .2s; }
.faq-q .ic::before { left: 0; top: 10px; width: 22px; height: 2px; }
.faq-q .ic::after { left: 10px; top: 0; width: 2px; height: 22px; }
.faq-q[aria-expanded="true"] .ic::after { transform: scaleY(0); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .25s ease; }
.faq-a p { padding: 0 4px 18px; color: var(--graphite); font-size: 14.8px; margin: 0; }

/* ---------- About ---------- */
.about-wrap { display: grid; grid-template-columns: 1.3fr 1fr; gap: 32px; align-items: start; }
@media (max-width: 860px) { .about-wrap { grid-template-columns: 1fr; } }
.about-card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.about-card dl { display: grid; grid-template-columns: auto 1fr; gap: 8px 14px; font-size: 14px; margin: 0; }
.about-card dt { color: var(--muted); }
.about-card dd { margin: 0; color: var(--navy); font-weight: 700; }
.disclaimer-box {
  background: var(--orange-soft); border: 1px solid #f0cba3; border-radius: var(--radius-sm);
  padding: 16px 18px; font-size: 13.8px; color: #7a4416; margin-top: 16px;
}

/* ---------- Footer ---------- */
.site-footer { background: var(--navy); color: #c7d0dd; padding: 46px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: 28px; }
@media (max-width: 860px) { .footer-grid { grid-template-columns: repeat(2, 1fr); } }
.footer-brand { font-family: var(--font-serif); color: #fff; font-size: 19px; font-weight: 700; margin-bottom: 10px; }
.site-footer h5 { color: #fff; font-size: 14px; margin: 0 0 12px; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.site-footer a { color: #b7c2d3; font-size: 14px; }
.site-footer a:hover { color: #fff; }
.footer-desc { font-size: 13.8px; color: #9aa7bb; max-width: 320px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.12); margin-top: 34px; padding-top: 20px; font-size: 13px; color: #92a0b5; display: flex; flex-wrap: wrap; gap: 8px 18px; justify-content: space-between; }
.footer-note { font-size: 12.6px; color: #7d8ba2; margin-top: 10px; line-height: 1.7; }

/* ---------- Back to top ---------- */
.to-top {
  position: fixed; right: 20px; bottom: 24px; width: 44px; height: 44px; border-radius: 50%;
  background: var(--navy); color: #fff; border: none; cursor: pointer; box-shadow: var(--shadow);
  opacity: 0; pointer-events: none; transition: opacity .2s; z-index: 90; font-size: 18px;
}
.to-top.show { opacity: 1; pointer-events: auto; }

/* ---------- Term expand (glossary chips) ---------- */
.term { border-bottom: 1px dashed var(--cyan); cursor: help; color: var(--navy); font-weight: 600; }
.term-pop {
  display: none; background: var(--navy); color: #fff; font-size: 12.6px; padding: 8px 12px; border-radius: 8px;
  position: absolute; max-width: 260px; z-index: 50; box-shadow: var(--shadow); line-height: 1.6;
}
.term-pop.show { display: block; }

/* ---------- Utility ---------- */
.mt-0 { margin-top: 0; }
.text-muted { color: var(--muted); }
.small { font-size: 13px; }
.center { text-align: center; }
.tbl-wrap { overflow-x: auto; margin: 16px 0; }
table.data-tbl { width: 100%; border-collapse: collapse; min-width: 480px; font-size: 14px; }
table.data-tbl th, table.data-tbl td { border: 1px solid var(--line); padding: 9px 12px; text-align: left; }
table.data-tbl th { background: var(--panel-soft); color: var(--navy); }

/* ---------- Page hero (secondary pages) ---------- */
.page-hero { background: linear-gradient(160deg, var(--navy) 0%, var(--navy-2) 70%); color: #eef2f6; padding: 46px 0 40px; }
.page-hero h1 { color: #fff; font-size: clamp(24px, 3.6vw, 34px); margin-bottom: 14px; }
.page-hero p { color: #cdd7e6; max-width: 760px; font-size: 16px; }
.breadcrumb { font-size: 13px; color: #9fb0c8; margin-bottom: 14px; }
.breadcrumb a { color: #cfe0f2; }

/* ---------- Concept grid on secondary pages ---------- */
.concept-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; }
.concept-card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 16px 18px; }
.concept-card b { color: var(--navy); display: block; margin-bottom: 4px; font-size: 14.5px; }
.concept-card span { font-size: 13.5px; color: var(--muted); }

/* ---------- Nav mobile ---------- */
@media (max-width: 900px) {
  .main-nav {
    position: fixed; top: 68px; left: 0; right: 0; bottom: 0; background: var(--bg);
    flex-direction: column; padding: 14px; gap: 4px; transform: translateX(100%);
    transition: transform .22s ease; overflow-y: auto; z-index: 99;
  }
  .main-nav.open { transform: translateX(0); }
  .main-nav a { padding: 14px 12px; font-size: 17px; border-bottom: 1px solid var(--line-soft); border-radius: 0; }
  .nav-toggle { display: block; }
}

@media (max-width: 480px) {
  section { padding: 40px 0; }
  .article-block { padding: 22px 16px; }
  .hero { padding: 44px 0 36px; }
}