:root {
    --ink: #22302c;
    --deep: #0f3329;
    --green: #1f5b49;
    --green-soft: #dce8de;
    --cream: #f7f1e5;
    --paper: #fffbf3;
    --muted: #6f7a73;
    --line: #dde1d8;
    --shadow: 0 22px 60px rgba(24, 55, 45, 0.12);
    --radius: 24px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    color: var(--ink);
    background: var(--paper);
    line-height: 1.75;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; height: auto; }
.container { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 251, 243, 0.92);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(31, 91, 73, 0.12);
}
.nav-wrap { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: inline-flex; align-items: center; gap: 12px; font-weight: 800; letter-spacing: 0.04em; }
.brand-mark {
    width: 42px; height: 42px; border-radius: 50%; display: grid; place-items: center;
    color: var(--cream); background: linear-gradient(135deg, var(--deep), var(--green)); box-shadow: var(--shadow);
}
.brand-text { font-size: 20px; }
.site-nav { display: flex; align-items: center; gap: 6px; }
.site-nav a { padding: 10px 14px; border-radius: 999px; color: #39534a; font-size: 15px; }
.site-nav a.active, .site-nav a:hover { background: var(--green-soft); color: var(--deep); }
.nav-toggle { display: none; border: 0; background: var(--green-soft); border-radius: 12px; padding: 8px 12px; color: var(--deep); font-size: 22px; }
.hero { padding: 92px 0 78px; overflow: hidden; }
.hero-home { background: radial-gradient(circle at 72% 20%, rgba(92, 133, 96, 0.22), transparent 34%), linear-gradient(180deg, #fffaf0 0%, #f0eadc 100%); }
.hero-grid, .page-hero-grid { display: grid; grid-template-columns: 1.02fr 0.98fr; align-items: center; gap: 56px; }
.hero-copy h1, .page-hero h1 { font-size: clamp(38px, 5.2vw, 72px); line-height: 1.08; margin: 10px 0 22px; color: var(--deep); letter-spacing: -0.04em; }
.page-hero h1 { font-size: clamp(34px, 4vw, 58px); }
.lead { font-size: 18px; color: #52645d; margin: 0 0 28px; max-width: 720px; }
.eyebrow { color: var(--green); font-weight: 800; letter-spacing: 0.16em; text-transform: uppercase; font-size: 13px; margin: 0 0 10px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin: 30px 0 22px; }
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 22px; border-radius: 999px; border: 1px solid var(--green); font-weight: 700; cursor: pointer; }
.btn.primary { background: var(--deep); color: var(--cream); border-color: var(--deep); }
.btn.secondary { background: transparent; color: var(--deep); }
.btn:hover { transform: translateY(-1px); box-shadow: 0 14px 32px rgba(15, 51, 41, 0.16); }
.domain-pill, .domain-note { display: inline-flex; padding: 10px 14px; border-radius: 999px; background: rgba(255,255,255,0.62); border: 1px solid var(--line); color: #40574f; font-size: 14px; }
.hero-art { border-radius: 36px; padding: 18px; background: rgba(255,255,255,0.38); box-shadow: var(--shadow); }
.section { padding: 82px 0; }
.page-hero { padding: 74px 0 62px; background: linear-gradient(180deg, #fbf3e4, #fffbf3); border-bottom: 1px solid var(--line); }
.section-head { max-width: 820px; margin-bottom: 36px; }
.section-head h2, .split h2, .contact-card h2 { margin: 0 0 14px; color: var(--deep); font-size: clamp(28px, 3vw, 42px); line-height: 1.18; letter-spacing: -0.02em; }
.section-head p, .split p, .contact-card p { color: var(--muted); margin-top: 0; }
.calm-band { background: #f2eadc; }
.soft-panel { background: linear-gradient(180deg, rgba(220,232,222,0.44), rgba(255,251,243,0.5)); }
.card-grid { display: grid; gap: 22px; }
.card-grid.five { grid-template-columns: repeat(5, 1fr); }
.card-grid.three { grid-template-columns: repeat(3, 1fr); }
.theme-card, .info-card, .path-card, .video-card, .topic-card, .quote-card, .contact-aside, .contact-form, .mini-card, .feature-list article {
    background: rgba(255,255,255,0.72); border: 1px solid rgba(31,91,73,0.14); border-radius: var(--radius); box-shadow: 0 12px 34px rgba(24,55,45,0.08);
}
.theme-card { padding: 14px; }
.theme-card img { border-radius: 18px; margin-bottom: 14px; }
.theme-card span, .tag, .topic-card span, .feature-list span, .timeline span { color: var(--green); font-weight: 800; font-size: 13px; letter-spacing: 0.08em; }
.theme-card h3, .info-card h3, .path-card h3, .video-body h2, .video-body h3, .topic-card h2, .feature-list h3, .timeline h2 { color: var(--deep); margin: 8px 0; line-height: 1.35; }
.theme-card p, .info-card p, .path-card p, .video-body p, .topic-card p, .feature-list p, .timeline p { color: var(--muted); margin: 0; font-size: 15px; }
.split { display: grid; grid-template-columns: 1fr 0.9fr; align-items: center; gap: 52px; }
.split.reverse { grid-template-columns: 0.9fr 1fr; }
.rounded-media { border-radius: 32px; box-shadow: var(--shadow); border: 1px solid rgba(31,91,73,0.14); }
.clean-list { list-style: none; padding: 0; margin: 24px 0 0; display: grid; gap: 12px; }
.clean-list li { position: relative; padding-left: 24px; color: #52645d; }
.clean-list li::before { content: ""; width: 9px; height: 9px; border-radius: 50%; background: var(--green); position: absolute; left: 0; top: 12px; }
.info-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; }
.info-row span { background: var(--green-soft); color: var(--deep); border-radius: 999px; padding: 8px 13px; font-weight: 700; }
.video-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.video-card { overflow: hidden; }
.video-card.large { grid-column: span 1; }
.video-body { padding: 20px; }
.editorial { background: var(--deep); color: var(--cream); }
.editorial .section-head h2, .editorial .feature-list h3 { color: var(--cream); }
.editorial .section-head p, .editorial .feature-list p { color: rgba(247,241,229,0.78); }
.feature-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-list article { padding: 26px; }
.editorial .feature-list article { background: rgba(255,255,255,0.08); border-color: rgba(255,255,255,0.14); }
.text-link { display: inline-flex; margin-top: 12px; font-weight: 800; color: var(--green); border-bottom: 2px solid var(--green); }
.faq-list { display: grid; gap: 14px; }
details { background: rgba(255,255,255,0.76); border: 1px solid var(--line); border-radius: 18px; padding: 18px 20px; }
summary { cursor: pointer; font-weight: 800; color: var(--deep); }
details p { color: var(--muted); margin-bottom: 0; }
.contact-strip { padding-top: 20px; }
.contact-card { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 34px; border-radius: 30px; background: linear-gradient(135deg, #f2eadc, #dce8de); border: 1px solid rgba(31,91,73,0.14); }
.quote-card { padding: 34px; font-size: 22px; color: var(--deep); }
.filter-row { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 30px; }
.filter-btn { border: 1px solid var(--green); background: transparent; color: var(--deep); border-radius: 999px; padding: 10px 17px; font-weight: 800; cursor: pointer; }
.filter-btn.active, .filter-btn:hover { background: var(--deep); color: var(--cream); }
.topic-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 22px; }
.topic-card { min-height: 260px; padding: 26px; display: flex; flex-direction: column; justify-content: flex-end; overflow: hidden; position: relative; }
.topic-card::before { content: ""; position: absolute; inset: 0; opacity: 0.2; background: radial-gradient(circle at 20% 10%, #fff 0 10%, transparent 32%); }
.topic-card > * { position: relative; }
.topic-card:nth-child(1), .topic-card:nth-child(2) { grid-column: span 3; }
.topic-card:nth-child(n+3) { grid-column: span 2; }
.nature-bg { background: linear-gradient(135deg, #e7efe4, #cbd9c4); }
.tech-bg { background: linear-gradient(135deg, #dfe9e8, #c7d4d1); }
.history-bg { background: linear-gradient(135deg, #efe1c8, #d9c7a9); }
.society-bg { background: linear-gradient(135deg, #e9e6dc, #d8d5ca); }
.human-bg { background: linear-gradient(135deg, #f2e5d9, #ddd0c4); }
.timeline { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; counter-reset: step; }
.timeline article { padding: 26px; border-left: 4px solid var(--green); background: rgba(255,255,255,0.7); border-radius: 22px; box-shadow: 0 12px 30px rgba(24,55,45,0.08); }
.contact-layout { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 28px; align-items: start; }
.contact-form { padding: 28px; display: grid; gap: 16px; }
.contact-form label { display: grid; gap: 6px; font-weight: 800; color: var(--deep); }
input, select, textarea { width: 100%; border: 1px solid var(--line); background: #fffdf8; border-radius: 14px; padding: 13px 14px; font: inherit; color: var(--ink); }
textarea { resize: vertical; }
.contact-aside { padding: 28px; }
.domain-big { font-size: clamp(26px, 4vw, 44px); color: var(--deep); font-weight: 900; line-height: 1.1; word-break: break-word; }
.mini-card { margin-top: 20px; padding: 18px; }
.site-footer { background: #102d26; color: rgba(247,241,229,0.88); padding: 44px 0; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr; gap: 28px; }
.footer-grid p { color: rgba(247,241,229,0.72); margin: 8px 0 0; }
@media (max-width: 1080px) {
    .card-grid.five { grid-template-columns: repeat(2, 1fr); }
    .video-grid { grid-template-columns: repeat(2, 1fr); }
    .timeline { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 820px) {
    .container { width: min(100% - 28px, 1180px); }
    .nav-toggle { display: inline-flex; }
    .site-nav { position: absolute; left: 14px; right: 14px; top: 76px; padding: 14px; border-radius: 22px; background: var(--paper); box-shadow: var(--shadow); border: 1px solid var(--line); display: none; flex-direction: column; align-items: stretch; }
    .site-nav.open { display: flex; }
    .hero, .section { padding: 56px 0; }
    .hero-grid, .page-hero-grid, .split, .split.reverse, .contact-layout { grid-template-columns: 1fr; gap: 28px; }
    .hero-copy h1, .page-hero h1 { font-size: 38px; }
    .card-grid.five, .card-grid.three, .video-grid, .feature-list, .timeline, .footer-grid { grid-template-columns: 1fr; }
    .topic-grid { grid-template-columns: 1fr; }
    .topic-card:nth-child(n) { grid-column: auto; }
    .contact-card { flex-direction: column; align-items: flex-start; }
}
@media (max-width: 520px) {
    .hero-actions { flex-direction: column; align-items: stretch; }
    .btn { width: 100%; }
    .domain-pill, .domain-note { border-radius: 16px; }
}