/* ===== Tokens — style A: clean business, teal palette + logo red accent ===== */
:root {
  --primary: #0f766e;       /* teal */
  --primary-dark: #115e59;
  --primary-deep: #134e4a;  /* headings / footer */
  --primary-light: #14b8a6;
  --primary-tint: #e3f1ef;
  --accent: #c8372d;        /* vermilion (logo C) — use sparingly */
  --ink: #1f2933;
  --muted: #5b6b73;
  --bg: #ffffff;
  --bg-alt: #f0f7f6;
  --line: #d7e6e4;
  --radius: 8px;
  --max: 1120px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
}

/* ===== Language switch ===== */
html[data-lang="en"] [lang="zh"],
html[data-lang="zh"] [lang="en"] { display: none !important; }

/* ===== Base ===== */
[hidden] { display: none !important; }
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 72px; }
body { margin: 0; font-family: var(--font); color: var(--ink); background: var(--bg); line-height: 1.7; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; display: block; }
a { color: var(--primary); }
h1, h2, h3, h4 { line-height: 1.3; margin: 0 0 .5em; letter-spacing: -.01em; }
.container { max-width: var(--max); margin: 0 auto; padding: 0 24px; }

/* ===== Header ===== */
.site-header { position: sticky; top: 0; z-index: 10; background: rgba(255,255,255,.96); border-bottom: 1px solid var(--line); backdrop-filter: blur(8px); }
.header-inner { display: flex; align-items: center; gap: 24px; height: 68px; }
.brand { display: flex; align-items: center; text-decoration: none; }
.brand-logo { height: 46px; width: auto; }
.nav { display: flex; gap: 28px; margin-left: auto; }
.nav a { color: var(--ink); text-decoration: none; font-size: 15px; font-weight: 500; padding: 4px 0; border-bottom: 2px solid transparent; }
.nav a:hover { color: var(--primary); border-bottom-color: var(--primary); }
.header-actions { display: flex; gap: 8px; }
.lang-toggle, .menu-toggle { border: 1px solid var(--line); background: #fff; border-radius: 6px; padding: 6px 12px; cursor: pointer; font: inherit; font-size: 14px; color: var(--ink); }
.lang-toggle:hover { border-color: var(--primary); color: var(--primary); }
.menu-toggle { display: none; }

/* ===== Hero ===== */
.hero { position: relative; overflow: hidden; background: linear-gradient(135deg, var(--primary-dark), var(--primary-light)); color: #fff; padding: 120px 0 112px; }
/* three slanted bars echoing the logo's E */
.hero::before, .hero::after, .hero-inner::after { content: ""; position: absolute; height: 56px; transform: skewX(-28deg); border-radius: 4px; pointer-events: none; }
.hero::before { right: -40px; top: 22%; width: 340px; background: rgba(255,255,255,.06); }
.hero::after { right: -40px; top: calc(22% + 160px); width: 340px; background: rgba(255,255,255,.06); }
.hero-inner { position: relative; z-index: 1; }
.hero-inner::after { right: -60px; top: 80px; width: 260px; background: rgba(255,255,255,.1); z-index: -1; }
.hero h1 { font-size: clamp(32px, 5vw, 54px); font-weight: 700; max-width: 780px; margin-bottom: 20px; }
.eyebrow { display: inline-flex; align-items: center; gap: 10px; letter-spacing: .08em; font-size: 13px; color: rgba(255,255,255,.8); margin: 0 0 20px; text-transform: uppercase; }
.eyebrow::before { content: ""; width: 28px; height: 3px; background: var(--accent); border-radius: 2px; }
.lead { font-size: 18px; max-width: 640px; color: rgba(255,255,255,.88); margin: 0; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 40px; }

/* ===== Buttons ===== */
.btn { display: inline-block; padding: 12px 24px; border-radius: 6px; text-decoration: none; font-weight: 600; font-size: 15px; transition: background .15s, color .15s, border-color .15s; }
.btn-primary { background: #fff; color: var(--primary-dark); }
.btn-primary:hover { background: var(--primary-tint); }
.btn-ghost { border: 1px solid rgba(255,255,255,.5); color: #fff; }
.btn-ghost:hover { border-color: #fff; background: rgba(255,255,255,.08); }
.btn-link { padding: 0; margin-top: auto; color: var(--primary); }
.btn-link:hover { color: var(--primary-dark); text-decoration: underline; }

/* ===== Sections ===== */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.section h2 { font-size: clamp(26px, 3.5vw, 34px); font-weight: 700; color: var(--primary-deep); }
.section h2::before { content: ""; display: block; width: 36px; height: 3px; background: var(--accent); border-radius: 2px; margin-bottom: 16px; }
.section-intro { max-width: 760px; color: var(--muted); font-size: 17px; margin: 0; }

/* Timeline — horizontal line with nodes */
.timeline { list-style: none; padding: 0; margin: 40px 0 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; position: relative; }
.timeline::before { content: ""; position: absolute; left: 0; right: 0; top: 34px; height: 2px; background: var(--primary-tint); }
.timeline li { position: relative; padding-top: 48px; padding-right: 8px; }
.timeline li::before { content: ""; position: absolute; top: 27px; left: 0; width: 16px; height: 16px; border-radius: 50%; background: var(--primary); box-shadow: 0 0 0 4px #fff; }
.timeline li.is-now::before { background: var(--accent); }
.tl-year { position: absolute; top: 0; left: 0; font-weight: 700; color: var(--primary); font-size: 15px; }
.timeline li.is-now .tl-year { color: var(--accent); }
.timeline h3 { font-size: 17px; margin: 0 0 4px; }
.timeline p { color: var(--muted); font-size: 14px; line-height: 1.6; margin: 0; }

/* Cards */
.cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; margin-top: 40px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; display: flex; flex-direction: column; transition: border-color .15s, box-shadow .15s; }
.card:hover { border-color: #b9d6d2; box-shadow: 0 8px 24px rgba(17,94,89,.08); }
.card-media { aspect-ratio: 16 / 9; width: 100%; object-fit: cover; display: block; }
.card-body { padding: 28px; display: flex; flex-direction: column; flex: 1; }
.card-tag { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--primary); font-weight: 700; margin: 0 0 8px; }
.card h3 { font-size: 21px; color: var(--primary-deep); }
.card p { color: var(--muted); margin-top: 0; }
.card-list { padding-left: 18px; color: var(--muted); margin: 0 0 20px; }
.card-list li { margin-bottom: 8px; }
.card-list li::marker { color: var(--primary); }
.card-list strong { color: var(--ink); }
.card-quote { font-style: italic; color: var(--primary) !important; }

/* Partners & footprints */
.partners-label { margin: 32px 0 12px; font-size: 13px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.partner-groups { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.partner-group { border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 24px; background: #fff; }
.partner-group h3 { font-size: 15px; text-transform: uppercase; letter-spacing: .06em; color: var(--primary-deep); margin: 0 0 12px; }
.partner-group ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 2px; }
.partner-group li { padding: 8px 0; border-bottom: 1px solid var(--bg-alt); font-weight: 500; color: var(--ink); }
.partner-group li:last-child { border-bottom: 0; }
.partner-group a { color: var(--ink); text-decoration: none; }
.partner-group a:hover { color: var(--primary); text-decoration: underline; }
.partner-group a::after { content: " ↗"; color: var(--primary); font-size: 13px; }
.partner-group h3 { display: flex; align-items: center; gap: 10px; }
.flag { width: 22px; height: 14px; border-radius: 2px; box-shadow: 0 0 0 1px rgba(0,0,0,.08); flex: none; }
.flag-ie { background: linear-gradient(90deg, #169b62 33.3%, #fff 33.3% 66.6%, #ff883e 66.6%); }
.flag-cn { background: #de2910; }
.gallery { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px 20px; margin-top: 40px; }
.gallery .placeholder { aspect-ratio: 4 / 3; border-radius: var(--radius); }
.gallery figure { margin: 0; }
.gallery figcaption { margin-top: 10px; font-size: 14px; color: var(--muted); }

/* Contact & Follow */
.section-tight { padding: 64px 0; }
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.info-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 32px; display: flex; flex-direction: column; gap: 18px; }
.info-card h2 { font-size: clamp(22px, 2.6vw, 28px); margin: 0 0 4px; }
.info-card h2::before { margin-bottom: 12px; }
.contact-item { display: flex; align-items: center; gap: 14px; color: var(--ink); text-decoration: none; font-weight: 500; font-size: 16px; line-height: 1.4; }
.contact-item small { display: block; font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); margin-bottom: 2px; }
a.contact-item:hover { color: var(--primary); }
.contact-icon { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 50%; background: var(--primary-tint); color: var(--primary); flex: none; }
.rednote-icon { border-radius: 10px; background: #ff2442; color: #fff; font-size: 11px; font-weight: 700; letter-spacing: -.02em; }
.follow-row { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.qr-mini { width: 88px; height: 88px; border-radius: 6px; flex: none; }

/* Placeholder images */
.placeholder { background: repeating-linear-gradient(45deg, #e3efed, #e3efed 10px, #edf5f4 10px, #edf5f4 20px); display: grid; place-items: center; color: var(--muted); font-size: 14px; }

/* Footer */
.site-footer { background: var(--primary-deep); color: rgba(255,255,255,.7); padding: 32px 0; font-size: 14px; }
.site-footer p { margin: 0; }

/* ===== Mobile ===== */
@media (max-width: 860px) {
  .menu-toggle { display: inline-block; }
  .header-actions { margin-left: auto; }
  .nav { display: none; position: absolute; top: 68px; left: 0; right: 0; flex-direction: column; gap: 0; background: #fff; border-bottom: 1px solid var(--line); }
  .nav.open { display: flex; }
  .nav a { padding: 14px 24px; border-top: 1px solid var(--line); border-bottom: 0; }
  .timeline { grid-template-columns: repeat(2, 1fr); row-gap: 32px; }
  .timeline::before { display: none; }
  .cards, .partner-groups { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .info-card { padding: 24px; }
  .gallery { grid-template-columns: 1fr 1fr; }
  .hero { padding: 88px 0 72px; }
  .hero::before, .hero::after { width: 200px; height: 40px; }
  .hero-inner::after { display: none; }
  .section { padding: 72px 0; }
  .section-tight { padding: 48px 0; }
}
@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .timeline, .gallery { grid-template-columns: 1fr; }
}