:root{
  --ink:#17324d;        /* 蓝图墨蓝：来自电机图纸 */
  --copper:#a4582e;     /* 铜色：来自电机绕组漆包线 */
  --paper:#f5f3ec;      /* 图纸米白打底 */
  --line:#c3cbd4;
  --muted:#5b6a78;
  --fs-hero:clamp(2rem,4.5vw,3.2rem);
  --fs-h2:clamp(1.35rem,2.5vw,1.8rem);
  --fs-body:1rem;
  --fs-small:.85rem;
  --fs-tiny:.72rem;
  --sp:24px;
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:"Source Han Sans SC","Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;background:var(--paper);color:var(--ink);font-size:var(--fs-body);line-height:1.75}
.wrap{max-width:1280px;margin:0 auto;padding:0 24px}
a{color:var(--copper)}
a:hover{text-decoration:underline}
a:focus-visible,button:focus-visible{outline:2px solid var(--copper);outline-offset:2px}

/* 页头 */
.site-header{border-bottom:3px solid var(--ink);background:var(--paper)}
.header-row{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:16px;padding:16px 24px}
.header-row nav{display:flex;flex-wrap:wrap;gap:16px;font-size:var(--fs-small);letter-spacing:.08em}
.header-row nav a{color:var(--ink);text-decoration:none;padding:4px 0;border-bottom:2px solid transparent}
.header-row nav a:hover{border-bottom-color:var(--copper)}

/* 面包屑 */
.breadcrumb{font-size:12px;letter-spacing:.12em;color:var(--muted);margin:24px 0;display:flex;gap:8px}
.breadcrumb a{color:var(--muted)}

/* kicker 编号标签 */
.kicker{font-size:var(--fs-tiny);letter-spacing:.25em;color:var(--copper);text-transform:uppercase;margin-bottom:12px;font-family:ui-monospace,Consolas,monospace}
h1,h2,h3{line-height:1.3;letter-spacing:.02em;font-weight:700}
h1{font-size:var(--fs-hero)}
h2{font-size:var(--fs-h2);margin-bottom:16px;border-left:4px solid var(--ink);padding-left:12px}
h3{font-size:1.1rem;margin-bottom:8px}

/* hero 变体：首页左右分栏 */
.hero{padding:64px 0 48px;display:grid;gap:32px}
.hero-left{grid-template-columns:minmax(0,3fr) minmax(0,2fr);align-items:center;border-bottom:1px solid var(--line)}
.hero-fig img{width:100%;height:auto;display:block;border:1px solid var(--ink)}
.lead{max-width:64ch;margin-top:16px}
.hero-narrow{max-width:72ch;padding-top:32px}
.hero-actions{margin-top:24px;display:flex;gap:12px;flex-wrap:wrap}
.btn{display:inline-block;background:var(--ink);color:var(--paper);padding:12px 24px;text-decoration:none;font-size:var(--fs-small);letter-spacing:.1em}
.btn:hover{background:var(--copper);color:#fff;text-decoration:none}
.btn-ghost{background:transparent;color:var(--ink);border:2px solid var(--ink);padding:10px 22px}
.btn-ghost:hover{background:var(--ink);color:var(--paper)}

/* 区块 */
.block{padding:48px 0;border-top:1px solid var(--line)}
.block-intro{max-width:64ch;margin-bottom:24px}

/* 能力三栏 */
.feature-cols{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.feat{border-top:3px solid var(--ink);padding-top:16px}
.feat p{color:var(--ink)}

/* 九宫格（契约结构） */
.items{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.item img{width:100%;height:auto;aspect-ratio:4/3;object-fit:cover;display:block}
@media(max-width:760px){.items{grid-template-columns:minmax(0,1fr)}}
.item{border:1px solid var(--line);padding:16px;background:#fbfaf6}
.item h2{font-size:1.05rem;border-left:none;padding-left:0;margin:12px 0 8px}
.item p{font-size:var(--fs-small);color:var(--muted);margin-bottom:8px}
.item ul{list-style:none;font-size:var(--fs-small)}
.item li{padding-left:16px;position:relative;margin-bottom:4px}
.item li::before{content:"—";position:absolute;left:0;color:var(--copper)}

/* 流程 */
.steps{list-style:none;counter-reset:s;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:24px}
.steps li{counter-increment:s;border-top:1px solid var(--ink);padding-top:16px}
.steps li::before{content:"0" counter(s);display:block;font-family:ui-monospace,Consolas,monospace;font-size:var(--fs-h2);color:var(--copper);margin-bottom:8px}
.steps strong{display:block;margin-bottom:8px}
.steps span{font-size:var(--fs-small);color:var(--muted)}
.steps-wide li{padding-bottom:8px}

/* FAQ */
.faq div{border-bottom:1px solid var(--line);padding:16px 0}
.faq dt{font-weight:700;margin-bottom:8px}
.faq dd{color:var(--muted)}
.faq-list .qa{border-bottom:1px solid var(--line);padding:16px 0}
.faq-list .qa h2{font-size:1.15rem;border-left:none;padding-left:0;margin-bottom:8px}
.faq-list .qa p{color:var(--muted)}

/* 关于页 */
.about-grid{display:grid;grid-template-columns:minmax(0,3fr) minmax(0,2fr);gap:32px;padding:48px 0;border-top:1px solid var(--line)}
.about-text h2{margin-top:32px}
.about-text h2:first-of-type{margin-top:0}
.about-text p{margin-bottom:16px;max-width:64ch}
.about-fig img{width:100%;height:auto;display:block;border:1px solid var(--ink);margin-bottom:24px}

/* 文章正文 */
.article-body{padding-bottom:64px}
.article-body h2{margin-top:48px}
.article-body p{max-width:66ch;margin-bottom:16px}
.article-body ul.check{list-style:none;max-width:66ch;margin-bottom:16px}
.article-body ul.check li{padding-left:24px;position:relative;margin-bottom:8px}
.article-body ul.check li::before{content:"✓";position:absolute;left:0;color:var(--copper);font-weight:700}
table.cmp{width:100%;border-collapse:collapse;margin:16px 0 24px;font-size:var(--fs-small)}
table.cmp th,table.cmp td{border:1px solid var(--line);padding:8px 12px;text-align:left}
table.cmp th{background:var(--ink);color:var(--paper)}

/* CTA */
.cta{background:var(--ink);color:var(--paper);margin:48px 0;padding:48px 32px}
.cta h2{border-left-color:var(--copper);color:var(--paper)}
.cta a{color:var(--copper);font-weight:700}

/* 页脚 */
.site-footer{border-top:3px solid var(--ink);margin-top:32px}
.foot-row{display:flex;flex-wrap:wrap;justify-content:space-between;gap:16px;padding:32px 24px;font-size:var(--fs-small);color:var(--muted)}
.foot-row nav{display:flex;flex-wrap:wrap;gap:16px}
.foot-row a{color:var(--muted)}

@media(max-width:900px){
  .hero-left,.about-grid{grid-template-columns:minmax(0,1fr)}
  .feature-cols{grid-template-columns:minmax(0,1fr)}
  .steps{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media(max-width:600px){
  .steps{grid-template-columns:minmax(0,1fr)}
}