/* AI工具指南 - 站点样式 */
:root{
  --bg:#ffffff; --bg-soft:#f6f8fb; --text:#1a2332; --muted:#5b6b82;
  --brand:#2456e6; --brand-dark:#1a43b8; --accent:#ff6b35;
  --border:#e6ebf2; --radius:14px; --maxw:1080px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",system-ui,sans-serif;
  color:var(--text);background:var(--bg);line-height:1.9;font-size:16px}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* 顶栏 */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.96);
  backdrop-filter:blur(8px);border-bottom:1px solid var(--border)}
.site-header .wrap{display:flex;align-items:center;gap:28px;height:64px}
.logo{font-size:22px;font-weight:800;color:var(--text);display:flex;align-items:center;gap:10px}
.logo:hover{text-decoration:none}
.logo-badge{width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,var(--brand),#6a8dff);
  display:inline-flex;align-items:center;justify-content:center;color:#fff;font-size:18px}
.main-nav{display:flex;gap:22px;margin-left:auto}
.main-nav a{color:var(--text);font-weight:500;font-size:15px}
.main-nav a:hover{color:var(--brand);text-decoration:none}

/* Hero */
.hero{background:linear-gradient(135deg,#eef3ff 0%,#f7f9ff 60%,#fff7f2 100%);
  border-bottom:1px solid var(--border);padding:56px 0 48px;text-align:center}
.hero h1{font-size:34px;letter-spacing:.5px;margin-bottom:12px}
.hero p{color:var(--muted);font-size:17px;max-width:640px;margin:0 auto}
.hero-tags{margin-top:18px;display:flex;gap:10px;justify-content:center;flex-wrap:wrap}
.hero-tags span{background:#fff;border:1px solid var(--border);border-radius:999px;
  padding:4px 14px;font-size:13px;color:var(--muted)}

/* 分类 */
.cats{padding:34px 0 6px}
.cat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.cat-card{background:var(--bg-soft);border:1px solid var(--border);border-radius:var(--radius);
  padding:20px 16px;text-align:center;color:var(--text);transition:.2s}
.cat-card:hover{transform:translateY(-3px);box-shadow:0 10px 24px rgba(36,86,230,.08);text-decoration:none}
.cat-card .ico{font-size:26px}
.cat-card h3{font-size:16px;margin:8px 0 4px}
.cat-card p{font-size:13px;color:var(--muted);line-height:1.6}

/* 文章列表 */
.section{padding:30px 0}
.section-head{display:flex;align-items:baseline;justify-content:space-between;margin-bottom:18px}
.section-head h2{font-size:22px}
.post-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}
.post-card{border:1px solid var(--border);border-radius:var(--radius);padding:24px;
  background:#fff;transition:.2s;display:flex;flex-direction:column}
.post-card:hover{box-shadow:0 12px 28px rgba(20,40,90,.08);transform:translateY(-2px)}
.post-card:hover{text-decoration:none}
.post-card .kicker{font-size:12px;color:var(--brand);font-weight:700;letter-spacing:1px;margin-bottom:8px}
.post-card h3{font-size:18px;line-height:1.6;color:var(--text);margin-bottom:10px}
.post-card p{font-size:14px;color:var(--muted);line-height:1.8;flex:1}
.post-card .meta{margin-top:14px;font-size:12px;color:#9aa7bb}

/* 文章页 */
.article{max-width:780px;margin:0 auto;padding:40px 20px 60px}
.article h1{font-size:30px;line-height:1.5;margin-bottom:14px}
.article .desc{color:var(--muted);font-size:15px;background:var(--bg-soft);
  border-left:4px solid var(--brand);padding:12px 16px;border-radius:0 10px 10px 0;margin-bottom:28px}
.article h2{font-size:22px;margin:34px 0 14px;padding-bottom:8px;border-bottom:2px solid var(--bg-soft)}
.article h3{font-size:18px;margin:26px 0 10px;color:var(--brand-dark)}
.article p{margin:12px 0}
.article ul,.article ol{margin:12px 0 12px 24px}
.article li{margin:6px 0}
.article strong{color:var(--text)}
.breadcrumb{font-size:13px;color:var(--muted);margin-bottom:18px}
.breadcrumb a{color:var(--muted)}
.related{margin-top:44px;border-top:1px solid var(--border);padding-top:24px}
.related h3{font-size:18px;margin-bottom:14px}
.related ul{list-style:none;margin:0}
.related li{margin:8px 0}

/* 广告位占位(部署后替换为 AdSense 代码) */
.ad-slot{background:var(--bg-soft);border:1px dashed #c3cede;border-radius:10px;
  color:#9aa7bb;font-size:13px;text-align:center;padding:26px;margin:28px 0}

/* 页脚 */
.site-footer{background:#101828;color:#c8d3e3;margin-top:40px;padding:44px 0 30px;font-size:14px}
.site-footer .cols{display:grid;grid-template-columns:2fr 1fr 1fr;gap:30px;margin-bottom:26px}
.site-footer h4{color:#fff;font-size:15px;margin-bottom:12px}
.site-footer a{color:#c8d3e3}
.site-footer p{line-height:1.9;color:#93a1b8}
.copyright{border-top:1px solid #22304a;padding-top:18px;font-size:12px;color:#6b7a93;
  display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px}

@media(max-width:720px){
  .cat-grid{grid-template-columns:repeat(2,1fr)}
  .post-grid{grid-template-columns:1fr}
  .hero h1{font-size:26px}
  .article h1{font-size:24px}
  .main-nav{display:none}
  .site-footer .cols{grid-template-columns:1fr}
}