:root{--ink:#2b2b28;--ink-soft:#66665e;--paper:#f7f5f0;--paper2:#efece4;
  --green:#2f4a3e;--clay:#9c6b4a;--gold:#b08d57;--gold-l:#c9ab77;
  --line:rgba(47,74,62,.14);
  --serif:"Noto Serif SC","Source Han Serif SC","Songti SC","STSong","SimSun",serif;
  --sans:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:var(--sans);color:var(--ink);background:var(--paper);line-height:1.9;letter-spacing:.02em}
img{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
.reveal{opacity:0;transform:translateY(28px);transition:opacity .8s ease,transform .8s ease}
.reveal.in{opacity:1;transform:none}
.wrap{max-width:1680px;margin:0 auto;padding:0 clamp(20px,3vw,64px)}
/* 页头图 */
.phero{position:relative;height:min(48vh,400px);min-height:280px;overflow:hidden;display:flex;align-items:flex-end}
.phero img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.phero .veil{position:absolute;inset:0;
  background:linear-gradient(180deg,rgba(26,38,32,.30) 0%,rgba(26,38,32,.34) 42%,rgba(26,38,32,.86) 100%)}
.phero .in{position:relative;z-index:2;width:100%;max-width:1680px;margin:0 auto;
  padding:0 clamp(20px,3vw,64px) 44px;color:#fff}
.phero .crumb{font-size:12.5px;color:rgba(255,255,255,.86);letter-spacing:.1em;margin-bottom:12px}
.phero .crumb a{border-bottom:1px solid rgba(255,255,255,.5)}
.phero h1{font-family:var(--serif);font-size:clamp(32px,4.6vw,52px);letter-spacing:.18em;font-weight:700;
  text-shadow:0 4px 26px rgba(0,0,0,.4)}
.phero .sub{margin-top:10px;font-size:14px;letter-spacing:.24em;opacity:.92}
/* 分区 */
section.sec{padding:clamp(56px,6.2vw,88px) clamp(20px,3vw,64px)}
section.sec.alt{background:var(--paper2)}
.sec .inner{max-width:1680px;margin:0 auto}
.bhead{display:flex;align-items:center;gap:20px;margin-bottom:10px}
.bhead h2{font-family:var(--serif);font-size:clamp(23px,2.8vw,34px);color:var(--green);
  letter-spacing:.1em;font-weight:700;white-space:nowrap}
.bhead i{flex:1;height:1px;background:var(--line)}
.bhead em{font-style:normal;font-size:11.5px;letter-spacing:.36em;color:var(--gold);white-space:nowrap}
.bsub{color:var(--ink-soft);font-size:14.5px;max-width:960px;text-align:justify;margin-bottom:6px}
.sec h2::after,.bhead + .bsub{margin-bottom:8px}
.note{margin:36px 0 0;font-size:12px;color:var(--ink-soft);border-top:1px dashed var(--line);padding-top:14px}
/* 页脚 */
.foot{background:var(--green);color:rgba(255,255,255,.82);text-align:center;
  padding:46px 5vw;font-size:12.5px;letter-spacing:.08em;line-height:2.1}
.foot b{display:block;font-family:var(--serif);font-size:18px;color:#fff;letter-spacing:.3em;margin-bottom:8px}
/* 通用图卡 */
.ph{position:relative;overflow:hidden;border:1px solid var(--line)}
.ph img{width:100%;object-fit:cover;transition:transform .7s}
.ph:hover img{transform:scale(1.05)}
.ph em{position:absolute;left:0;top:0;font-style:normal;font-family:var(--serif);font-size:12px;
  letter-spacing:.16em;color:#fff;background:rgba(47,74,62,.9);padding:5px 14px;z-index:2}
.ph i{position:absolute;right:0;bottom:0;font-style:normal;font-size:10.5px;color:#fff;
  background:rgba(47,74,62,.72);padding:3px 11px;letter-spacing:.12em;z-index:2}
@media (min-width:1500px){
  section.sec{padding:clamp(52px,9vw,64px) clamp(20px,3vw,64px)}
  .bhead{margin-bottom:14px}
}

/* ---------------- 教程白皮书 ---------------- */
.glead{background:var(--paper2);border-left:4px solid var(--gold);border-radius:0 14px 14px 0;
  padding:clamp(18px,2.4vw,30px) clamp(20px,2.6vw,36px);margin:30px 0 44px;font-size:clamp(14.5px,1.15vw,16.5px);color:var(--ink)}
.glead b{color:var(--green)}
.gsteps{display:grid;gap:clamp(26px,3vw,44px);margin:0 0 46px}
.gstep{display:grid;grid-template-columns:minmax(280px,1.08fr) minmax(240px,.92fr);gap:clamp(20px,2.6vw,44px);align-items:center}
.gstep:nth-child(even){grid-template-columns:minmax(240px,.92fr) minmax(280px,1.08fr)}
.gstep:nth-child(even) .gfig{order:2}
.gfig{position:relative;border:1px solid var(--line);background:#fff;box-shadow:0 10px 30px rgba(43,43,40,.08);overflow:hidden}
.gfig img{width:100%;display:block}
.gfig i{position:absolute;left:0;top:0;z-index:2;background:var(--green);color:#fff;font-style:normal;
  font-size:12px;letter-spacing:.12em;padding:6px 14px;border-radius:0 0 10px 0}
.gstep .gt{position:relative;padding-left:54px}
.gno{position:absolute;left:0;top:0;width:40px;height:40px;border-radius:50%;background:var(--green);
  color:#fff;display:flex;align-items:center;justify-content:center;font-family:var(--serif);font-size:19px}
.gstep h3{font-family:var(--serif);font-size:clamp(18px,1.5vw,21px);color:var(--green);letter-spacing:.06em}
.gstep p{margin-top:10px;color:var(--ink-soft);font-size:clamp(13.5px,1.05vw,15px);text-align:justify}
.gtip{background:var(--paper2);border:1px dashed rgba(176,141,87,.5);border-radius:14px;
  padding:clamp(18px,2.2vw,28px) clamp(20px,2.6vw,34px);margin:0 0 40px}
.gtip h3{font-family:var(--serif);color:var(--clay);font-size:17px;letter-spacing:.14em;margin-bottom:12px}
.gtip li{color:var(--ink-soft);font-size:14px;margin:7px 0 0 22px}
.glinks{display:flex;flex-wrap:wrap;gap:12px;border-top:1px solid var(--line);padding-top:24px}
.glinks a{font-size:14px;color:var(--green);background:var(--paper2);border:1px solid rgba(47,74,62,.2);
  padding:9px 20px;border-radius:999px;letter-spacing:.06em;transition:.25s}
.glinks a:hover{background:var(--green);color:#fff}
@media (max-width:900px){.gstep,.gstep:nth-child(even){grid-template-columns:1fr}
  .gstep:nth-child(even) .gfig{order:0}.gstep .gt{padding-left:0}.gno{position:static;margin-bottom:10px}}