/* ==========================================================================
   快柠檬 falemonios.com.cn —— 硅芯 · 晶片 (冷硅灰 + 深空蓝 + 金色走线)
   左侧垂直导航 + 晶片 hero + PCB 走线矩阵,冷调科技感,与紫猫/光网/黄铜三站区分
   ========================================================================== */

:root{
  --bg:#eef1f6;            /* 冷硅灰浅底 */
  --bg-soft:#e3e9f2;
  --bg-deep:#0b1830;       /* 深空蓝:侧栏 + 页脚 */
  --bg-deep-2:#0d1f3d;
  --card:#ffffff;
  --card-2:#f4f7fb;
  --ink:#16243c;           /* 深蓝灰正文 */
  --muted:#55688a;
  --faint:#8a9bb8;
  --primary:#1b4998;       /* 深空蓝 */
  --primary-deep:#143a7a;
  --mid:#3374b6;
  --blue:#4593cb;
  --gold:#f39800;          /* 金色走线 */
  --gold-soft:#ffb347;
  --grad:linear-gradient(135deg,#1b4998 0%,#3374b6 52%,#4593cb 100%);
  --grad-gold:linear-gradient(135deg,#f39800 0%,#ffb347 100%);
  --grad-soft:linear-gradient(135deg,rgba(27,73,152,.08),rgba(69,147,203,.08));
  --line:rgba(22,36,60,.12);
  --line-strong:rgba(22,36,60,.22);
  --good:#2f8f5b;
  --good-bg:rgba(47,143,91,.10);
  --shadow:0 10px 30px rgba(20,40,70,.12);
  --shadow-lg:0 24px 60px rgba(20,40,70,.20);
  --radius:16px;
  --radius-sm:10px;
  --font:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --mono:"SFMono-Regular",Consolas,"Liberation Mono",Menlo,monospace;
}

*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:var(--font);
  background:var(--bg);
  color:var(--ink);
  line-height:1.8;
  font-size:16px;
  overflow-x:hidden;
}
img{max-width:100%;display:block}
a{color:var(--primary);text-decoration:none}
a:hover{color:var(--primary-deep)}
h1,h2,h3,h4{line-height:1.3;font-weight:800;letter-spacing:-.01em}
.wrap{max-width:1160px;margin:0 auto;padding:0 24px}

/* ==========================================================================
   左侧垂直导航 (核心差异化:整站外壳从顶栏改为侧栏)
   ========================================================================== */
.sidenav{
  position:fixed;inset:0 auto 0 0;width:264px;z-index:90;
  background:linear-gradient(180deg,#0d1f3d 0%,#0b1830 100%);
  color:#cfe0f5;
  display:flex;flex-direction:column;
  padding:26px 20px 20px;
  border-right:1px solid rgba(243,152,0,.28);
  overflow-y:auto;
}
.sidenav::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:140px;pointer-events:none;
  background:radial-gradient(360px 140px at 20% 100%,rgba(243,152,0,.14),transparent 70%);
}
.side-brand{display:flex;align-items:center;gap:12px;color:#fff;margin-bottom:6px}
.side-brand:hover{color:#fff}
.side-mark{width:40px;height:40px;border-radius:10px;box-shadow:0 6px 18px rgba(0,0,0,.4);flex-shrink:0;background:#fff}
.side-brandtext{display:flex;flex-direction:column;line-height:1.25}
.side-name{font-weight:800;font-size:19px;letter-spacing:-.01em}
.side-sub{font-size:10.5px;color:#8fb3dd;letter-spacing:.1em;font-weight:600;font-family:var(--mono)}
.side-tagline{
  display:block;font-size:11px;color:#6f8fc0;letter-spacing:.06em;
  padding:9px 0 14px;margin-bottom:14px;border-bottom:1px solid rgba(143,179,221,.18);
}
.side-nav{display:flex;flex-direction:column;gap:18px;position:relative;z-index:1}
.side-group{display:flex;flex-direction:column;gap:2px}
.side-glabel{
  font-size:10.5px;font-weight:800;letter-spacing:.16em;text-transform:uppercase;
  color:#f39800;font-family:var(--mono);margin-bottom:6px;padding-left:10px;
}
.side-group a{
  display:block;color:#bcd2ec;font-size:14px;font-weight:600;
  padding:8px 10px;border-radius:9px;border-left:2px solid transparent;
  transition:.16s;
}
.side-group a:hover{background:rgba(69,147,203,.14);color:#fff;border-left-color:var(--gold)}
.side-group a.on{background:rgba(69,147,203,.20);color:#fff;border-left-color:var(--gold);font-weight:700}
.side-foot{margin-top:auto;padding-top:18px;position:relative;z-index:1;display:flex;flex-direction:column;gap:12px}
.side-status{display:flex;align-items:center;gap:8px;font-size:12px;color:#8fb3dd;font-family:var(--mono)}
.led{width:8px;height:8px;border-radius:50%;background:#2fbf6f;box-shadow:0 0 10px #2fbf6f;animation:pulse 2s infinite}
.side-cta{width:100%}
.nav-toggle{
  display:none;position:fixed;top:14px;left:14px;z-index:120;
  width:44px;height:44px;border-radius:11px;border:none;cursor:pointer;
  background:var(--bg-deep);color:#fff;font-size:22px;
  box-shadow:var(--shadow-lg);
}
.main-area{margin-left:264px;min-height:100vh;display:flex;flex-direction:column}
.main-area main{flex:1 0 auto}

/* ==========================================================================
   按钮
   ========================================================================== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  font-weight:700;border-radius:11px;cursor:pointer;border:1px solid transparent;
  padding:11px 22px;font-size:15px;transition:.18s;line-height:1.2;
}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 8px 22px rgba(27,73,152,.32)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 14px 32px rgba(27,73,152,.44);color:#fff}
.btn-ghost{background:var(--card);color:var(--ink);border:1px solid var(--line-strong)}
.btn-ghost:hover{border-color:var(--primary);background:var(--card-2)}
.btn-outline{border:1.5px solid var(--primary);color:var(--primary);background:transparent}
.btn-outline:hover{background:var(--grad);color:#fff}
.btn-sm{padding:8px 16px;font-size:13.5px}
.btn-lg{padding:14px 28px;font-size:16px}

/* ==========================================================================
   hero:晶片分屏 (左侧文案 + 右侧晶片 SVG,虚化电路板背景)
   ========================================================================== */
.hero-chip{
  position:relative;padding:76px 0 72px;overflow:hidden;
  background:linear-gradient(180deg,#f6f9fd 0%,var(--bg) 100%);
  border-bottom:1px solid var(--line);
}
.hero-chip::before{
  content:"";position:absolute;inset:0;
  background-image:url(../images/circuit-board.jpg);
  background-size:cover;background-position:center;
  opacity:.10;filter:blur(6px) saturate(.75);
}
.hero-chip::after{
  content:"";position:absolute;left:0;right:0;top:0;height:3px;
  background:var(--grad-gold);
}
.hero-grid{
  position:relative;z-index:2;
  display:grid;grid-template-columns:minmax(0,1.04fr) minmax(0,.96fr);
  gap:48px;align-items:center;
}
.hero-copy{min-width:0}
.hero-kicker{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--mono);font-size:12px;font-weight:700;letter-spacing:.16em;
  text-transform:uppercase;color:var(--primary-deep);
  padding:6px 0;
}
.hero-kicker .dot{display:inline-block;width:7px;height:7px;border-radius:50%;background:var(--grad-gold);animation:pulse 2s infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.3}}
.hero-title{font-size:clamp(34px,5vw,56px);font-weight:800;letter-spacing:-.02em;margin:22px 0 18px}
.hero-title .hl{
  background:linear-gradient(90deg,#1b4998,#4593cb 55%,#f39800 120%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.hero-sub{font-size:16.5px;color:var(--muted);max-width:620px;margin-bottom:30px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap}
.hero-trust{display:flex;gap:10px;flex-wrap:wrap;margin-top:26px}
.trust-item{
  font-size:12.5px;color:var(--muted);font-weight:600;
  background:var(--card);border:1px solid var(--line);
  padding:6px 14px;border-radius:999px;
}
.hero-visual{
  position:relative;z-index:2;min-width:0;
  background:linear-gradient(160deg,rgba(255,255,255,.9),rgba(244,247,251,.6));
  border:1px solid var(--line);border-radius:18px;padding:16px;
  box-shadow:var(--shadow-lg);
}
.hero-visual svg{width:100%;height:auto;display:block}

/* ==========================================================================
   区块 / 标题
   ========================================================================== */
.section{padding:64px 0}
.section.alt{background:var(--bg-soft)}
.sec-head{max-width:720px;margin:0 auto 40px;text-align:center}
.sec-head h2{font-size:clamp(26px,3.4vw,38px);margin:12px 0 8px}
.sec-head p{color:var(--muted);font-size:15.5px}
.kicker{
  display:inline-block;font-size:12px;font-weight:800;letter-spacing:.18em;
  color:var(--gold);text-transform:uppercase;font-family:var(--mono);
}

/* 统计条 */
.stat-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.stat-card{
  display:flex;align-items:center;gap:14px;background:var(--card);
  border:1px solid var(--line);border-radius:var(--radius);padding:20px;
  box-shadow:var(--shadow);
}
.stat-card.good{border-top:3px solid var(--gold)}
.stat-ic{font-size:26px}
.stat-num{font-size:18px;font-weight:800;line-height:1.2}
.stat-lbl{font-size:12.5px;color:var(--muted);margin-top:2px}

/* bento */
.bento{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.bento-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px;box-shadow:var(--shadow);transition:.2s;position:relative;overflow:hidden;
}
.bento-card::before{content:"";position:absolute;left:0;top:0;width:100%;height:3px;background:var(--grad);opacity:0;transition:.2s}
.bento-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--line-strong)}
.bento-card:hover::before{opacity:1}
.bento-card .ic{font-size:30px;margin-bottom:14px}
.bento-card h3{font-size:18px;margin-bottom:8px}
.bento-card p{font-size:14px;color:var(--muted)}

/* 招牌 SVG 容器 */
.signature{max-width:900px;margin:0 auto;display:block;width:100%;height:auto}
.spectrum{max-width:900px;margin:0 auto;display:block;width:100%;height:auto}
.spectrum-note,.sig-note{text-align:center;color:var(--faint);font-size:12.5px;margin-top:12px}

/* 步骤 */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.step{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px;position:relative;box-shadow:var(--shadow);
}
.step .n{
  width:42px;height:42px;border-radius:11px;background:var(--grad);color:#fff;
  display:flex;align-items:center;justify-content:center;font-weight:800;font-size:19px;
  margin-bottom:16px;
}
.step h3{font-size:17px;margin-bottom:8px}
.step p{font-size:14px;color:var(--muted)}

/* 卡片网格 / 快速入口 */
.rel-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.rel-grid.single{grid-template-columns:repeat(4,1fr)}
.rel-grid.narrow{max-width:880px;margin:0 auto}
.rel-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px;box-shadow:var(--shadow);transition:.2s;display:block;color:var(--ink);
}
.rel-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);color:var(--ink);border-color:var(--line-strong)}
.rel-card .tag{
  display:inline-block;font-size:11px;font-weight:800;letter-spacing:.06em;
  color:var(--primary-deep);background:var(--grad-soft);
  padding:3px 10px;border-radius:999px;margin-bottom:12px;
}
.rel-card h4{font-size:16px;margin-bottom:6px}
.rel-card p{font-size:13px;color:var(--muted)}

/* 场景墙 */
.sc-wall{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.sc-card{
  position:relative;border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);display:block;color:#fff;min-height:180px;
}
.sc-card img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:.4s;filter:brightness(.72) saturate(.9)}
.sc-card:hover img{transform:scale(1.06)}
.sc-cap{
  position:absolute;inset:auto 0 0 0;padding:44px 18px 18px;z-index:2;
  background:linear-gradient(180deg,transparent,rgba(11,24,48,.94));
}
.sc-cap h4{font-size:16px;margin-bottom:3px}
.sc-cap p{font-size:12.5px;opacity:.85}

/* 左右图文 */
.split{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center}
.split.rev .img{order:-1}
.split h2{font-size:clamp(24px,3vw,32px);margin-bottom:14px}
.split p{color:var(--muted);margin-bottom:12px}
.split ul{color:var(--muted);padding-left:20px;display:grid;gap:8px;margin-bottom:18px}
.split .img img{border-radius:var(--radius);box-shadow:var(--shadow-lg)}
.img-frame{border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow-lg);border:1px solid var(--line)}
.img-frame img{width:100%;height:100%;object-fit:cover}

/* 表格 */
.table-wrap{overflow-x:auto;border-radius:var(--radius);border:1px solid var(--line);box-shadow:var(--shadow)}
table{width:100%;border-collapse:collapse;background:var(--card);min-width:520px}
th{background:var(--grad-soft);color:var(--primary-deep);font-weight:700;text-align:left}
th,td{padding:14px 18px;font-size:14px;border-bottom:1px solid var(--line)}
tr:last-child td{border-bottom:none}
td{color:var(--muted)}
td:first-child{color:var(--ink);font-weight:600}

/* FAQ */
.faq-group{margin-bottom:36px}
.faq-group>h2{font-size:22px;margin-bottom:16px}
.faq-group details{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius-sm);
  margin-bottom:12px;overflow:hidden;box-shadow:var(--shadow);
}
.faq-group summary{
  cursor:pointer;padding:18px 22px;font-weight:700;font-size:15.5px;list-style:none;
  display:flex;justify-content:space-between;align-items:center;
}
.faq-group summary::after{content:"+";font-size:22px;color:var(--gold);font-weight:400}
.faq-group details[open] summary::after{content:"−"}
.faq-a{padding:0 22px 20px;color:var(--muted);font-size:14.5px}

/* CTA 横条 */
.cta-band{
  background:var(--grad);border-radius:20px;padding:52px 40px;text-align:center;
  color:#fff;box-shadow:var(--shadow-lg);position:relative;overflow:hidden;
}
.cta-band::before{
  content:"";position:absolute;inset:0;
  background:
    radial-gradient(500px 260px at 80% 0%,rgba(255,255,255,.22),transparent 60%),
    radial-gradient(400px 300px at 12% 100%,rgba(243,152,0,.22),transparent 60%);
}
.cta-band>*{position:relative;z-index:2}
.cta-band h2{font-size:clamp(24px,3vw,32px);margin-bottom:10px}
.cta-band p{opacity:.92;margin-bottom:26px}
.cta-band .btn-ghost{background:#0b1830;color:#ffd08a;border:none}

/* page-hero(内页) */
.page-hero{
  background:
    radial-gradient(800px 400px at 50% -20%,rgba(69,147,203,.16),transparent 60%),
    var(--grad-soft);
  border-bottom:1px solid var(--line);
  padding:56px 0;text-align:center;
}
.page-hero h1{font-size:clamp(28px,4vw,40px);margin-bottom:12px}
.page-hero p{color:var(--muted);max-width:720px;margin:0 auto;font-size:15.5px}

/* 文章 */
.article-body{padding:48px 0}
.article-hero{
  background:
    radial-gradient(800px 400px at 50% -20%,rgba(69,147,203,.16),transparent 60%),
    var(--grad-soft);
  border-bottom:1px solid var(--line);padding:48px 0 40px;
}
.article-hero h1{font-size:clamp(26px,3.8vw,38px);margin:14px 0 12px;max-width:820px}
.article-hero p{color:var(--muted);max-width:820px;font-size:15.5px}
.article-meta{display:flex;gap:18px;margin-top:16px;flex-wrap:wrap}
.article-meta span{font-size:13px;color:var(--faint);font-weight:600}
.article-layout{display:grid;grid-template-columns:240px 1fr;gap:44px;max-width:1080px;margin:0 auto;padding:0 24px;align-items:start}
.toc{
  position:sticky;top:24px;background:var(--card);border:1px solid var(--line);
  border-radius:var(--radius);padding:20px;box-shadow:var(--shadow);
}
.toc h4{font-size:13px;letter-spacing:.08em;color:var(--gold);margin-bottom:12px;text-transform:uppercase}
.toc a{display:block;font-size:13.5px;color:var(--muted);padding:6px 0;border-bottom:1px dashed var(--line)}
.toc a:last-child{border-bottom:none}
.toc a:hover{color:var(--primary-deep)}
.prose{max-width:760px}
.prose h2{font-size:24px;margin:34px 0 14px;padding-top:8px}
.prose p{color:#33415e;margin-bottom:16px}
.prose ul,.prose ol{color:#33415e;padding-left:22px;margin:0 0 18px;display:grid;gap:8px}
.prose blockquote{
  border-left:4px solid var(--gold);background:var(--grad-soft);
  padding:16px 20px;border-radius:0 12px 12px 0;margin:20px 0;color:var(--muted);
}
.prose figure{margin:24px 0}
.prose figure img{border-radius:var(--radius);box-shadow:var(--shadow)}
.prose figcaption{text-align:center;font-size:12.5px;color:var(--faint);margin-top:10px}
.tip,.callout{
  border-radius:var(--radius-sm);padding:16px 18px;margin:20px 0;font-size:14.5px;
}
.tip{background:var(--grad-soft);border:1px solid var(--line-strong);color:#33415e}
.callout{background:var(--good-bg);border:1px solid rgba(47,143,91,.3);color:#276645}

/* 分享 */
.share{display:flex;gap:10px;margin:32px 0;flex-wrap:wrap}
.share a{
  font-size:13px;font-weight:600;color:var(--muted);
  border:1px solid var(--line);border-radius:999px;padding:7px 16px;background:var(--card);
}
.share a:hover{border-color:var(--primary);color:var(--primary-deep)}

/* 面包屑 */
.breadcrumb{font-size:13.5px;color:var(--muted);margin-bottom:12px}
.breadcrumb a{color:var(--primary);font-weight:600}
.breadcrumb .sep{margin:0 8px;color:var(--faint)}

/* 页脚 */
.mastfoot{background:var(--bg-deep);color:#c3d4ea;margin-top:40px;border-top:3px solid var(--gold)}
.mastfoot .wrap{padding:56px 24px 0}
.mf-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:36px;padding-bottom:40px}
.mf-brand .wordmark{color:#fff;margin-bottom:16px;display:flex;align-items:center;gap:10px}
.mf-brand .wm-mark{width:34px;height:34px;border-radius:9px;background:#fff}
.mf-brand .wm-text{display:flex;flex-direction:column;line-height:1.3;gap:2px}
.mf-brand .wm-name{font-weight:800;font-size:18px}
.mf-brand .wm-sub{font-size:10.5px;color:#8fb3dd;letter-spacing:.1em;font-family:var(--mono)}
.mf-brand p{font-size:14px;color:#9fb4d2;max-width:320px}
.mf-col h4{color:#e6eef9;font-size:14px;margin-bottom:16px;letter-spacing:.02em}
.mf-col a{display:block;font-size:13.5px;color:#9fb4d2;padding:5px 0}
.mf-col a:hover{color:#ffc15e}
.foot-line{border-top:1px solid rgba(195,212,234,.16);padding:20px 0;text-align:center;font-size:13px;color:#8fb3dd}

/* 返回顶部 */
.backtop{
  position:fixed;right:22px;bottom:22px;width:46px;height:46px;border-radius:50%;
  background:var(--grad);color:#fff;border:none;font-size:20px;cursor:pointer;
  box-shadow:var(--shadow-lg);opacity:0;visibility:hidden;transition:.25s;z-index:80;
}
.backtop.show{opacity:1;visibility:visible}

/* 工具页 */
.center-hero{min-height:60vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:60px 24px}
.center-hero h1{font-size:44px;margin-bottom:12px}
.center-hero p{color:var(--muted);margin-bottom:24px}
.search-box{display:flex;gap:10px;max-width:520px;margin:0 auto}
.search-box input{
  flex:1;padding:13px 18px;border:1.5px solid var(--line-strong);border-radius:11px;
  font:inherit;font-size:15px;background:var(--card);color:var(--ink);
}
.search-box input:focus{outline:none;border-color:var(--primary)}
.sitemap-list{max-width:820px}
.sitemap-list h2{font-size:20px;margin:26px 0 12px;color:var(--primary-deep)}
.sitemap-list>div{display:grid;gap:6px}
.sitemap-list a{color:var(--muted);font-size:14.5px;padding:4px 0}
.sitemap-list a:hover{color:var(--primary-deep)}

/* 动效 */
.reveal{opacity:0;transform:translateY(22px);transition:.6s ease}
.reveal.in{opacity:1;transform:none}

/* ==========================================================================
   响应式
   ========================================================================== */
@media(max-width:960px){
  .sidenav{
    transform:translateX(-100%);transition:transform .26s ease;
    box-shadow:var(--shadow-lg);
  }
  body.nav-open .sidenav{transform:none}
  body.nav-open::after{
    content:"";position:fixed;inset:0;z-index:85;background:rgba(11,24,48,.5);
  }
  .nav-toggle{display:flex;align-items:center;justify-content:center}
  .main-area{margin-left:0}
  .hero-grid{grid-template-columns:1fr;gap:36px}
  .stat-strip{grid-template-columns:repeat(2,1fr)}
  .bento{grid-template-columns:repeat(2,1fr)}
  .steps{grid-template-columns:1fr}
  .rel-grid,.rel-grid.single,.sc-wall{grid-template-columns:repeat(2,1fr)}
  .split{grid-template-columns:1fr;gap:28px}
  .split.rev .img{order:0}
  .article-layout{grid-template-columns:1fr}
  .toc{position:static}
  .mf-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:620px){
  .rel-grid,.rel-grid.single,.sc-wall{grid-template-columns:1fr}
  .stat-strip{grid-template-columns:1fr}
  .bento{grid-template-columns:1fr}
  .hero-chip{padding:56px 0 52px}
  .mf-grid{grid-template-columns:1fr}
  .hero-cta .btn{width:100%}
}