/* === Base Reset & Variables === */
:root {
  --color-bg: #0d1117;
  --color-surface: #161b22;
  --color-border: #30363d;
  --color-text: #e6edf3;
  --color-muted: #8b949e;
  --color-accent: #2ea043;
  --color-accent-hover: #3fb950;
  --color-header-bg: rgba(13,17,23,0.92);
  --radius-card: 10px;
  --radius-btn: 6px;
  --shadow-card: 0 4px 24px rgba(0,0,0,0.4);
  --transition-base: 0.25s cubic-bezier(0.16,1,0.3,1);
  --font-main: 'PingFang SC','Microsoft YaHei',Arial,sans-serif;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:var(--font-main);background:var(--color-bg);color:var(--color-text);line-height:1.7;min-height:100dvh}
img{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none}
ul,ol{list-style:none}
button{font-family:inherit;cursor:pointer;border:none;background:none}

/* === Layout === */
.container{max-width:1200px;margin:0 auto;padding:0 1.25rem}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap}

/* === Header / Nav === */
.site-header{position:sticky;top:0;z-index:100;background:var(--color-header-bg);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);border-bottom:1px solid var(--color-border)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:68px;gap:2rem}
.site-logo{display:flex;align-items:center;gap:0.625rem;flex-shrink:0}
.site-logo img{height:36px;width:auto}
.site-logo-text{font-size:1.125rem;font-weight:700;color:#fff;letter-spacing:-0.01em}
.main-nav{display:flex;align-items:center;gap:0.25rem;flex:1}
.main-nav a{display:inline-flex;align-items:center;padding:0.5rem 0.875rem;font-size:0.9375rem;color:var(--color-muted);border-radius:var(--radius-btn);transition:color var(--transition-base),background var(--transition-base);white-space:nowrap}
.main-nav a:hover,.main-nav a[aria-current="page"]{color:#fff;background:rgba(255,255,255,0.07)}
.nav-cta{display:inline-flex;align-items:center;padding:0.5rem 1.125rem;background:var(--color-accent);color:#fff;font-weight:600;font-size:0.9375rem;border-radius:var(--radius-btn);transition:background var(--transition-base),transform 0.15s}
.nav-cta:hover{background:var(--color-accent-hover);transform:translateY(-1px)}

/* Mobile nav */
.nav-toggle{display:none;flex-direction:column;gap:5px;padding:0.5rem;cursor:pointer;border-radius:var(--radius-btn)}
.nav-toggle span{display:block;width:22px;height:2px;background:var(--color-text);border-radius:2px;transition:transform var(--transition-base),opacity var(--transition-base)}
.nav-mobile{position:fixed;inset:0;z-index:99;background:var(--color-bg);display:flex;flex-direction:column;padding:1.5rem;gap:0.25rem;transform:translateX(100%);transition:transform var(--transition-base)}
.nav-mobile.open{transform:translateX(0)}
.nav-mobile a{display:block;padding:0.875rem 1rem;font-size:1.0625rem;color:var(--color-text);border-radius:var(--radius-btn);border-bottom:1px solid var(--color-border)}
.nav-mobile-close{margin-bottom:1rem;font-size:1.25rem;color:var(--color-muted);background:none;border:none;cursor:pointer;padding:0.5rem}

@media(max-width:768px){
  .main-nav,.nav-cta{display:none}
  .nav-toggle{display:flex}
}

/* === Footer === */
.site-footer{background:var(--color-surface);border-top:1px solid var(--color-border);padding:2.5rem 0 1.5rem;margin-top:4rem}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:2.5rem;margin-bottom:2rem}
.footer-brand p{color:var(--color-muted);font-size:0.875rem;line-height:1.8;margin-top:0.75rem;max-width:340px}
.footer-col h4{font-size:0.8125rem;font-weight:600;text-transform:uppercase;letter-spacing:0.08em;color:var(--color-muted);margin-bottom:0.875rem}
.footer-col a{display:block;color:var(--color-text);font-size:0.9375rem;padding:0.3rem 0;transition:color var(--transition-base)}
.footer-col a:hover{color:var(--color-accent)}
.footer-bottom{border-top:1px solid var(--color-border);padding-top:1.25rem;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:0.75rem}
.footer-bottom p{color:var(--color-muted);font-size:0.8125rem}

@media(max-width:768px){
  .footer-grid{grid-template-columns:1fr;gap:1.5rem}
}

/* === Buttons === */
.btn{display:inline-flex;align-items:center;justify-content:center;padding:0.625rem 1.375rem;font-weight:600;font-size:0.9375rem;border-radius:var(--radius-btn);transition:all var(--transition-base)}
.btn-primary{background:var(--color-accent);color:#fff}
.btn-primary:hover{background:var(--color-accent-hover);transform:translateY(-1px);box-shadow:0 6px 20px rgba(46,160,67,0.35)}
.btn-outline{border:1px solid var(--color-border);color:var(--color-text);background:transparent}
.btn-outline:hover{border-color:var(--color-accent);color:var(--color-accent)}

/* === Cards === */
.card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-card);overflow:hidden;transition:transform var(--transition-base),box-shadow var(--transition-base),border-color var(--transition-base)}
.card:hover{transform:translateY(-3px);box-shadow:var(--shadow-card);border-color:rgba(46,160,67,0.4)}
.card-img-wrap{aspect-ratio:16/9;overflow:hidden}
.card-img-wrap img{width:100%;height:100%;object-fit:cover;transition:transform 0.5s cubic-bezier(0.16,1,0.3,1)}
.card:hover .card-img-wrap img{transform:scale(1.05)}
.card-body{padding:1.125rem 1.25rem 1.25rem}
.card-meta{font-size:0.8125rem;color:var(--color-muted);margin-bottom:0.5rem}
.card-title{font-size:1.0625rem;font-weight:700;line-height:1.4;margin-bottom:0.625rem;color:#fff}
.card-title a{color:inherit;transition:color var(--transition-base)}
.card-title a:hover{color:var(--color-accent)}
.card-excerpt{font-size:0.875rem;color:var(--color-muted);line-height:1.7;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}

/* === Article Sidebar === */
.article-layout{display:grid;grid-template-columns:1fr 300px;gap:2.5rem;align-items:start;padding:2.5rem 0}
.article-main{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-card);padding:2rem;min-width:0}
.article-header{margin-bottom:1.5rem;padding-bottom:1.5rem;border-bottom:1px solid var(--color-border)}
.article-breadcrumb{font-size:0.8125rem;color:var(--color-muted);margin-bottom:0.875rem}
.article-breadcrumb a{color:var(--color-muted);transition:color var(--transition-base)}
.article-breadcrumb a:hover{color:var(--color-accent)}
.article-breadcrumb span{margin:0 0.375rem}
.article-h1{font-size:1.625rem;font-weight:800;line-height:1.3;color:#fff;margin-bottom:0.75rem}
.article-info{display:flex;align-items:center;gap:1.25rem;font-size:0.8125rem;color:var(--color-muted)}
.article-info span{display:flex;align-items:center;gap:0.3rem}
.article-content{font-size:1rem;line-height:1.85;color:var(--color-text)}
.article-content h2{font-size:1.25rem;font-weight:700;color:#fff;margin:2rem 0 0.875rem;padding-bottom:0.5rem;border-bottom:1px solid var(--color-border)}
.article-content h3{font-size:1.0625rem;font-weight:600;color:#fff;margin:1.5rem 0 0.625rem}
.article-content p{margin-bottom:1.125rem}
.article-content ul,.article-content ol{margin:0.875rem 0 1.125rem 1.5rem}
.article-content ul{list-style:disc}
.article-content ol{list-style:decimal}
.article-content li{margin-bottom:0.4rem}
.article-content img{margin:1.25rem 0;border-radius:8px;border:1px solid var(--color-border)}
.article-content strong{color:#fff}
.article-faq{margin-top:2.5rem;padding-top:2rem;border-top:1px solid var(--color-border)}
.article-faq h2{font-size:1.25rem;font-weight:700;color:#fff;margin-bottom:1.25rem}
.faq-item{margin-bottom:1.25rem;padding:1rem 1.125rem;background:rgba(255,255,255,0.03);border-radius:8px;border:1px solid var(--color-border)}
.faq-q{font-weight:600;color:#fff;margin-bottom:0.5rem}
.faq-a{color:var(--color-muted);font-size:0.9375rem;line-height:1.7}
.article-nav-links{display:flex;justify-content:space-between;gap:1rem;margin-top:2rem;padding-top:1.5rem;border-top:1px solid var(--color-border)}
.article-nav-links a{display:inline-flex;align-items:center;gap:0.4rem;font-size:0.875rem;color:var(--color-muted);transition:color var(--transition-base)}
.article-nav-links a:hover{color:var(--color-accent)}

.article-sidebar{position:sticky;top:88px}
.sidebar-widget{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-card);padding:1.25rem;margin-bottom:1.25rem}
.sidebar-widget h3{font-size:0.875rem;font-weight:600;text-transform:uppercase;letter-spacing:0.07em;color:var(--color-muted);margin-bottom:1rem;padding-bottom:0.75rem;border-bottom:1px solid var(--color-border)}
.sidebar-article-list{list-style:none;display:flex;flex-direction:column;gap:0.75rem}
.sidebar-article-list li{display:flex;gap:0.75rem;align-items:flex-start}
.sidebar-thumb{width:72px;height:48px;object-fit:cover;border-radius:6px;flex-shrink:0;border:1px solid var(--color-border)}
.sidebar-info{flex:1;min-width:0}
.sidebar-title{font-size:0.875rem;font-weight:600;line-height:1.4;color:#fff;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;transition:color var(--transition-base)}
.sidebar-title:hover{color:var(--color-accent)}
.sidebar-date{font-size:0.75rem;color:var(--color-muted);margin-top:0.25rem}

@media(max-width:900px){
  .article-layout{grid-template-columns:1fr}
  .article-sidebar{position:static}
}

/* === Category Page === */
.cat-hero{background:linear-gradient(135deg,#0d1117 0%,#161b22 100%);border-bottom:1px solid var(--color-border);padding:2.5rem 0}
.cat-hero h1{font-size:1.75rem;font-weight:800;color:#fff;margin-bottom:0.5rem}
.cat-hero p{color:var(--color-muted);font-size:0.9375rem}
.article-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1.5rem;padding:2.5rem 0}
@media(max-width:900px){.article-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:580px){.article-grid{grid-template-columns:1fr}}

/* === Homepage === */
.home-hero{position:relative;height:520px;display:flex;align-items:center;overflow:hidden;margin-bottom:3rem}
.hero-bg{position:absolute;inset:0;z-index:0}
.hero-bg img{width:100%;height:100%;object-fit:cover;opacity:0.35}
.hero-overlay{position:absolute;inset:0;background:linear-gradient(to right,rgba(13,17,23,0.95) 40%,rgba(13,17,23,0.3));z-index:1}
.hero-content{position:relative;z-index:2;max-width:580px}
.hero-eyebrow{display:inline-block;font-size:0.8125rem;font-weight:600;text-transform:uppercase;letter-spacing:0.1em;color:var(--color-accent);margin-bottom:1rem}
.hero-h1{font-size:2.5rem;font-weight:900;line-height:1.2;color:#fff;margin-bottom:1rem;letter-spacing:-0.02em}
.hero-h1 em{font-style:normal;color:var(--color-accent)}
.hero-desc{font-size:1.0625rem;color:var(--color-muted);margin-bottom:1.75rem;line-height:1.7}
.hero-actions{display:flex;gap:0.875rem;flex-wrap:wrap}
.section{padding:3rem 0}
.section-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:2rem;flex-wrap:wrap;gap:1rem}
.section-title{font-size:1.375rem;font-weight:800;color:#fff}
.section-title span{color:var(--color-accent)}
.stats-bar{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-card);padding:1.5rem 2rem;display:flex;justify-content:space-around;gap:1rem;flex-wrap:wrap;margin-bottom:3rem}
.stats-item{text-align:center}
.stats-num{font-size:1.75rem;font-weight:900;color:var(--color-accent);line-height:1.2}
.stats-label{font-size:0.8125rem;color:var(--color-muted);margin-top:0.25rem}
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1.5rem;margin-bottom:3rem}
.feature-card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-card);padding:1.75rem;text-align:center;transition:all var(--transition-base)}
.feature-card:hover{border-color:rgba(46,160,67,0.5);transform:translateY(-4px);box-shadow:0 8px 32px rgba(0,0,0,0.5)}
.feature-icon{width:52px;height:52px;margin:0 auto 1.125rem;display:flex;align-items:center;justify-content:center;background:rgba(46,160,67,0.12);border-radius:14px;font-size:1.5rem}
.feature-card h3{font-size:1.0625rem;font-weight:700;color:#fff;margin-bottom:0.625rem}
.feature-card p{font-size:0.875rem;color:var(--color-muted);line-height:1.7}
.home-articles{display:grid;grid-template-columns:repeat(3,1fr);gap:1.5rem;margin-bottom:3rem}
@media(max-width:900px){.feature-grid,.home-articles{grid-template-columns:repeat(2,1fr)}}
@media(max-width:580px){.feature-grid,.home-articles{grid-template-columns:1fr}.hero-h1{font-size:1.875rem}.home-hero{height:420px}}

/* === About Page === */
.about-page{padding:3rem 0}
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:3rem;align-items:center;padding:2.5rem 0}
@media(max-width:768px){.about-grid{grid-template-columns:1fr}}

/* === JSON-LD === */