:root{--bg:#f3efe7;--paper:#fffdfa;--ink:#2f312f;--muted:#67706b;--line:#d8cfbf;--green:#43685e;--gold:#a26e34;--sage:#ebf0ea;--sand:#f1e8da}
*{box-sizing:border-box}
body{margin:0;background:radial-gradient(circle at top,#fbf7ef 0%,#f3efe7 52%,#ece7dc 100%);color:var(--ink);font-family:"Songti SC","Noto Serif CJK SC",serif;line-height:1.76}
a{color:inherit;text-decoration:none}
.topbar{position:sticky;top:0;z-index:10;display:flex;justify-content:space-between;align-items:center;padding:16px 5vw;background:rgba(243,239,231,.92);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.brand{font-weight:800;letter-spacing:.04em}
.topbar nav{display:flex;gap:18px;font-family:"PingFang SC",sans-serif;color:var(--muted);font-size:14px}
main{width:min(1180px,90vw);margin:0 auto;padding:44px 0 72px}
.hero{display:grid;grid-template-columns:1.45fr .85fr;gap:34px;align-items:stretch;padding:54px 0}
.hero h1{font-size:clamp(50px,8vw,92px);line-height:.96;margin:14px 0}
.lead{font-size:21px;color:#4e574f;max-width:760px}
.section-note{color:var(--muted);margin-top:-6px}
.eyebrow{font-family:"PingFang SC",sans-serif;font-size:12px;text-transform:uppercase;letter-spacing:.16em;color:var(--gold);font-weight:700}
.hero-panel,.panel,.card,.deep-card,.sidebar,.plate-detail,.viewer-panel,.viewer-figure,.answer-panel{background:var(--paper);border:1px solid var(--line);border-radius:24px;box-shadow:0 18px 50px rgba(44,38,28,.06)}
.hero-panel,.panel,.viewer-panel,.sidebar{padding:24px}
.button{display:inline-flex;padding:12px 18px;margin-right:10px;border-radius:999px;background:var(--green);color:white;font-family:"PingFang SC",sans-serif}
.button.secondary{background:transparent;color:var(--green);border:1px solid var(--green)}
section{margin:40px 0}
h1,h2,h3{line-height:1.2}
h2{font-size:28px}
.route-grid{display:grid;grid-template-columns:repeat(6,1fr);gap:10px}
.route-grid div{padding:18px;border-radius:18px;background:var(--sage);text-align:center;font-weight:700}
.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.card{display:block;padding:24px;transition:.18s transform,.18s box-shadow}
.card:hover,.thumb-button:hover,.mini-plate:hover,.side-plate:hover{transform:translateY(-2px);box-shadow:0 18px 50px rgba(44,38,28,.08)}
.chapter-card small{color:var(--muted);font-family:"PingFang SC",sans-serif}
.concept-grid{grid-template-columns:repeat(4,1fr)}
.plate-band{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.plate-mini,.side-plate,.mini-plate{display:block;background:var(--paper);border:1px solid var(--line);border-radius:18px;padding:10px;font-family:"PingFang SC",sans-serif;color:var(--muted);transition:.18s transform,.18s box-shadow}
.plate-mini img,.side-plate img,.plate-card img,.mini-plate img,.thumb-button img{width:100%;aspect-ratio:4/3;object-fit:contain;background:#f7f2e9;border-radius:14px;padding:6px}
.layout{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:28px}
.content>section{margin:30px 0}
.tag-row{display:flex;flex-wrap:wrap;gap:10px}
.tag{display:inline-flex;padding:8px 12px;border-radius:999px;background:#edf2f1;color:#335760;font-family:"PingFang SC",sans-serif;font-size:14px;margin:4px}
.deep-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}
.deep-card{padding:22px}
.deep-card blockquote{margin:14px 0 0;padding-left:14px;border-left:4px solid var(--gold);color:#5d5f64}
.sidebar{position:sticky;top:86px;align-self:start}
.two{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.path{display:flex;gap:12px;flex-wrap:wrap;margin-top:30px}
.path a{padding:10px 14px;border-radius:14px;background:#edf2f1;color:#375b65;font-family:"PingFang SC",sans-serif}
.plate-grid{grid-template-columns:repeat(4,1fr)}
.plate-card{padding:14px}
.plate-detail{padding:18px}
.plate-detail img{width:100%;max-height:620px;object-fit:contain;background:#f7f2e9;border-radius:18px}
.mini-plate-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
.viewer-panel h2{margin-top:0}
.viewer-figure{margin:0;padding:14px}
.viewer-main{width:100%;aspect-ratio:4/3;object-fit:contain;background:#f7f2e9;border-radius:18px;padding:10px}
.viewer-figure figcaption{margin-top:10px;color:var(--muted);font-family:"PingFang SC",sans-serif}
.thumb-strip{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:14px}
.thumb-button{display:flex;flex-direction:column;gap:8px;padding:10px;border:1px solid var(--line);background:var(--paper);border-radius:18px;color:var(--muted);cursor:pointer;transition:.18s transform,.18s box-shadow}
.thumb-button.is-active{outline:2px solid #7fa69a}
.thumb-button span,.mini-plate span,.plate-mini span,.side-plate span{font-size:13px;line-height:1.45}
.answer-button{display:block;width:100%;padding:14px 16px;border-radius:16px;border:1px solid var(--line);background:#eef2f1;color:#375b65;text-align:left;font:inherit;cursor:pointer}
.answer-panel{margin-top:12px;padding:18px}
table{width:100%;border-collapse:collapse;background:var(--paper);border:1px solid var(--line);border-radius:20px;overflow:hidden}
th,td{padding:16px;border-bottom:1px solid var(--line);text-align:left}
th{background:#ece7dc;font-family:"PingFang SC",sans-serif}
@media (max-width:900px){
  .hero,.layout{grid-template-columns:1fr}
  .grid,.concept-grid,.plate-grid,.mini-plate-grid{grid-template-columns:1fr}
  .plate-band,.route-grid,.thumb-strip{grid-template-columns:repeat(2,1fr)}
  .sidebar{position:static}
  .deep-grid,.two{grid-template-columns:1fr}
  .topbar{align-items:flex-start;gap:10px;flex-direction:column}
}