*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
--blue-deep:#1A3C7E;--blue:#2563A8;--blue-light:#EBF4FF;--blue-50:#F0F6FF;
--red:#C8102E;--red-light:#FFF1F1;--red-dark:#A00D24;
--white:#FFFFFF;--bg-gray:#F7FAFC;--bg-gray2:#EEF2F7;
--text:#1A202C;--text-gray:#4A5568;--text-light:#718096;
--border:#E2E8F0;--radius:12px;--radius-sm:8px;
--shadow:0 2px 12px rgba(26,60,126,.08);--shadow-lg:0 8px 30px rgba(26,60,126,.12);
--transition:all .3s cubic-bezier(.4,0,.2,1);--container:1200px
}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;color:var(--text);line-height:1.7;background:var(--white);overflow-x:hidden;font-size:15px}
a{color:inherit;text-decoration:none;transition:var(--transition)}
img{max-width:100%;height:auto;display:block}
.container{max-width:var(--container);margin:0 auto;padding:0 20px}
.section{padding:60px 0}
.section-title{text-align:center;margin-bottom:40px}
.section-title h2{font-size:28px;color:var(--blue-deep);font-weight:700;margin-bottom:10px}
.section-title .subtitle{color:var(--text-gray);font-size:15px}
.section-title .divider{width:50px;height:3px;background:linear-gradient(90deg,var(--red),var(--blue));margin:12px auto 0;border-radius:2px}

/* ===== Navigation ===== */
.header{position:fixed;top:0;left:0;right:0;z-index:999;background:rgba(255,255,255,.98);box-shadow:0 1px 6px rgba(0,0,0,.06);transition:var(--transition)}
.nav{display:flex;align-items:center;justify-content:space-between;height:64px}
.nav-logo{font-size:20px;font-weight:700;color:var(--blue-deep);white-space:nowrap;display:flex;align-items:center}
.nav-logo-img{height:44px;width:auto;display:block}
.nav-menu{display:flex;align-items:center;list-style:none;gap:4px}
.nav-menu>li{position:relative}
.nav-menu>li>a{display:block;padding:0 14px;line-height:64px;font-size:15px;font-weight:500;color:var(--text)}
.nav-menu>li>a:hover,.nav-menu>li>a.active{color:var(--red)}
.nav-menu>li>a::after{content:'';position:absolute;bottom:0;left:50%;transform:translateX(-50%);width:0;height:2px;background:var(--red);transition:var(--transition)}
.nav-menu>li>a:hover::after,.nav-menu>li>a.active::after{width:60%}
.nav-dropdown{position:absolute;top:64px;left:50%;transform:translateX(-50%) translateY(10px);background:var(--white);box-shadow:var(--shadow-lg);border-radius:var(--radius-sm);min-width:200px;padding:10px 0;opacity:0;visibility:hidden;transition:var(--transition)}
.nav-menu>li:hover .nav-dropdown{opacity:1;visibility:visible;transform:translateX(-50%) translateY(0)}
.nav-dropdown a{display:block;padding:8px 20px;font-size:14px;color:var(--text-gray)}
.nav-dropdown a:hover{color:var(--red);background:var(--red-light)}
.nav-dropdown a.current{color:var(--red);font-weight:600}
.nav-toggle{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:8px}
.nav-toggle span{width:24px;height:2px;background:var(--blue-deep);transition:var(--transition)}
.nav-toggle.active span:nth-child(1){transform:rotate(45deg) translate(5px,5px)}
.nav-toggle.active span:nth-child(2){opacity:0}
.nav-toggle.active span:nth-child(3){transform:rotate(-45deg) translate(5px,-5px)}

/* ===== Hero Banner ===== */
.hero{margin-top:64px;position:relative;overflow:hidden;background:linear-gradient(135deg,var(--blue-deep) 0%,var(--blue) 100%)}
.hero::before{content:'';position:absolute;top:0;left:0;right:0;bottom:0;background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1200 240'%3E%3Cpath d='M0,120 Q300,60 600,120 T1200,120 L1200,240 L0,240 Z' fill='rgba(255,255,255,0.03)'/%3E%3Cpath d='M0,160 Q300,100 600,160 T1200,160 L1200,240 L0,240 Z' fill='rgba(255,255,255,0.02)'/%3E%3C/svg%3E") center/cover}
.hero-content{position:relative;z-index:2;color:var(--white);text-align:center;padding:50px 20px}
.hero-content h1{font-size:32px;font-weight:700;margin-bottom:12px;text-shadow:0 2px 10px rgba(0,0,0,.2)}
.hero-content p{font-size:16px;opacity:.9;margin-bottom:6px}
.hero-tag{display:inline-block;background:var(--red);color:var(--white);padding:6px 18px;border-radius:20px;font-size:14px;margin-bottom:16px;font-weight:500}

/* ===== Breadcrumb ===== */
.breadcrumb{background:var(--bg-gray);padding:12px 0;border-bottom:1px solid var(--border)}
.breadcrumb-list{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--text-light)}
.breadcrumb-list a{color:var(--blue);transition:var(--transition)}
.breadcrumb-list a:hover{color:var(--red)}
.breadcrumb-sep{color:var(--text-light)}

/* ===== Article Layout ===== */
.article-section{padding:40px 0 60px}
.article-layout{display:grid;grid-template-columns:1fr 320px;gap:32px;align-items:flex-start}

/* Category Tabs */
.cat-tabs{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:28px}
.cat-tab{padding:8px 20px;border-radius:20px;font-size:14px;font-weight:500;color:var(--text-gray);background:var(--bg-gray);cursor:pointer;transition:var(--transition);border:1px solid transparent}
.cat-tab:hover{color:var(--blue);border-color:var(--blue)}
.cat-tab.active{background:var(--blue-deep);color:var(--white);border-color:var(--blue-deep)}

/* Featured Article */
.featured-article{display:grid;grid-template-columns:340px 1fr;gap:0;background:var(--white);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);margin-bottom:32px;transition:var(--transition)}
.featured-article:hover{box-shadow:var(--shadow-lg);transform:translateY(-4px)}
.featured-thumb{height:100%;min-height:220px;display:flex;align-items:center;justify-content:center;position:relative;overflow:hidden;background:linear-gradient(135deg,#1A3C7E,#2563A8)}
.featured-thumb img{width:100%;height:100%;object-fit:cover;display:block}
.featured-thumb-overlay{position:absolute;inset:0;background:linear-gradient(180deg,rgba(0,0,0,0) 50%,rgba(0,0,0,.35) 100%)}
.featured-body{padding:28px 28px 28px 24px}
.featured-badge{display:inline-block;background:var(--red);color:var(--white);padding:3px 10px;border-radius:12px;font-size:12px;font-weight:600;margin-bottom:10px}
.featured-body h3{font-size:20px;color:var(--blue-deep);margin-bottom:10px;line-height:1.4}
.featured-body h3 a{color:inherit}
.featured-body h3 a:hover{color:var(--red)}
.featured-body p{font-size:14px;color:var(--text-gray);line-height:1.7;margin-bottom:12px}
.featured-meta{display:flex;gap:16px;font-size:13px;color:var(--text-light)}
.featured-meta span{display:flex;align-items:center;gap:4px}
.featured-meta svg{width:14px;height:14px;opacity:.6}

/* Article Grid */
.article-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.article-card{background:var(--white);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:var(--transition);display:flex;flex-direction:column}
.article-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg)}
.article-card-thumb{height:160px;display:block;position:relative;overflow:hidden}
.article-card-thumb img{width:100%;height:100%;object-fit:cover;display:block;transition:transform .4s ease}
.article-card:hover .article-card-thumb img{transform:scale(1.05)}
.article-card-cat{position:absolute;top:10px;left:10px;padding:3px 10px;border-radius:12px;font-size:11px;font-weight:600;color:var(--white);backdrop-filter:blur(4px)}
.article-card-body{padding:18px;flex:1;display:flex;flex-direction:column}
.article-card-body h3{font-size:16px;color:var(--text);margin-bottom:8px;line-height:1.4}
.article-card-body h3 a{color:inherit}
.article-card-body h3 a:hover{color:var(--red)}
.article-card-body p{font-size:13px;color:var(--text-gray);line-height:1.6;margin-bottom:12px;flex:1}
.article-card-meta{display:flex;gap:12px;font-size:12px;color:var(--text-light)}
.article-card-meta span{display:flex;align-items:center;gap:3px}
.article-card-meta svg{width:12px;height:12px;opacity:.5}

/* Pagination */
.pagination{display:flex;justify-content:center;align-items:center;gap:6px;margin-top:36px}
.pagination a,.pagination span{display:flex;align-items:center;justify-content:center;min-width:36px;height:36px;padding:0 10px;border-radius:var(--radius-sm);font-size:14px;color:var(--text-gray);background:var(--white);border:1px solid var(--border);transition:var(--transition);cursor:pointer}
.pagination a:hover{border-color:var(--blue);color:var(--blue)}
.pagination .current{background:var(--blue-deep);color:var(--white);border-color:var(--blue-deep);font-weight:600}
.pagination .disabled{color:var(--text-light);opacity:.5;cursor:default}

/* ===== Sidebar ===== */
.sidebar{position:sticky;top:80px}
.widget{background:var(--white);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow);margin-bottom:20px}
.widget h3{font-size:16px;color:var(--blue-deep);margin-bottom:16px;padding-bottom:12px;border-bottom:2px solid var(--border);position:relative}
.widget h3::after{content:'';position:absolute;bottom:-2px;left:0;width:40px;height:2px;background:var(--red)}

/* Hot Articles Widget */
.hot-list{list-style:none}
.hot-list li{display:flex;align-items:flex-start;gap:10px;padding:10px 0;border-bottom:1px dashed var(--border)}
.hot-list li:last-child{border-bottom:none}
.hot-num{width:24px;height:24px;flex-shrink:0;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:700;color:var(--white)}
.hot-num.top1{background:var(--red)}
.hot-num.top2{background:#E84042}
.hot-num.top3{background:var(--blue)}
.hot-num.top4,.hot-num.top5{background:var(--text-light)}
.hot-list li a{font-size:13px;color:var(--text);line-height:1.5}
.hot-list li a:hover{color:var(--red)}

/* Tag Cloud Widget */
.tag-cloud{display:flex;flex-wrap:wrap;gap:8px}
.tag-cloud a{padding:5px 12px;border-radius:16px;font-size:13px;color:var(--text-gray);background:var(--bg-gray);transition:var(--transition)}
.tag-cloud a:hover{background:var(--blue-light);color:var(--blue-deep)}

/* Course Links Widget */
.course-links{list-style:none}
.course-links .cl-group{margin-bottom:12px}
.course-links .cl-title{font-size:13px;font-weight:600;color:var(--text);margin-bottom:6px}
.course-links .cl-items{display:flex;flex-wrap:wrap;gap:6px}
.course-links .cl-items a{padding:3px 10px;border-radius:12px;font-size:12px;color:var(--blue);background:var(--blue-50);transition:var(--transition)}
.course-links .cl-items a:hover{background:var(--blue);color:var(--white)}

/* CTA Widget */
.cta-widget{background:linear-gradient(135deg,var(--blue-deep),var(--blue));border-radius:var(--radius);padding:24px;text-align:center;color:var(--white)}
.cta-widget h3{color:var(--white);border:none;font-size:17px;margin-bottom:8px}
.cta-widget p{font-size:13px;opacity:.85;margin-bottom:14px}
.cta-widget .cta-btn{display:inline-block;padding:10px 28px;background:var(--red);color:var(--white);border-radius:20px;font-size:14px;font-weight:600;transition:var(--transition)}
.cta-widget .cta-btn:hover{background:var(--red-dark);transform:translateY(-2px)}

/* ===== Internal Links Section ===== */
.cert-nav-section{background:var(--bg-gray)}
.cert-nav-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.cert-nav-card{background:var(--white);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.cert-nav-card-header{padding:18px 20px;color:var(--white)}
.cert-nav-card:nth-child(1) .cert-nav-card-header{background:linear-gradient(135deg,#1A3C7E,#2563A8)}
.cert-nav-card:nth-child(2) .cert-nav-card-header{background:linear-gradient(135deg,#2563A8,#3B82C4)}
.cert-nav-card:nth-child(3) .cert-nav-card-header{background:linear-gradient(135deg,#C8102E,#E84042)}
.cert-nav-card-header h3{font-size:17px;margin-bottom:4px}
.cert-nav-card-header p{font-size:13px;opacity:.85}
.cert-nav-card-body{padding:16px 20px}
.cert-nav-card-body a{display:flex;align-items:center;justify-content:space-between;padding:10px 0;border-bottom:1px dashed var(--border);font-size:14px;color:var(--text)}
.cert-nav-card-body a:last-child{border-bottom:none}
.cert-nav-card-body a:hover{color:var(--red)}
.cert-nav-card-body a span{font-size:12px;color:var(--text-light)}
.cert-nav-card-body a:hover span{color:var(--red)}

/* ===== Footer ===== */
.footer{background:#0F1B3D;color:rgba(255,255,255,.75);padding:50px 0 0}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.2fr;gap:32px;padding-bottom:32px;border-bottom:1px solid rgba(255,255,255,.1)}
.footer-col h4{font-size:15px;color:var(--white);margin-bottom:14px;font-weight:600}
.footer-col p{font-size:13px;line-height:1.7;margin-bottom:6px}
.footer-col ul{list-style:none}
.footer-col ul li{padding:4px 0;font-size:13px}
.footer-col ul li a{color:rgba(255,255,255,.7);transition:var(--transition)}
.footer-col ul li a:hover{color:var(--white)}
.footer-col .footer-sub-title{font-size:13px;color:rgba(255,255,255,.5);margin-top:10px;margin-bottom:4px}
.footer-contact p{display:flex;align-items:flex-start;gap:8px;font-size:13px;margin-bottom:6px}
.footer-contact svg{width:16px;height:16px;flex-shrink:0;margin-top:3px;opacity:.7}
.footer-qr{text-align:center;margin-top:10px}
.footer-qr .qr-box{width:100px;height:100px;background:rgba(255,255,255,.1);border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center;margin:0 auto 6px}
.footer-qr .qr-box svg{width:60px;height:60px;opacity:.8}
.footer-qr p{font-size:12px;text-align:center}
.footer-bottom{padding:20px 0;text-align:center}
.footer-bottom p{font-size:12px;color:rgba(255,255,255,.5);margin-bottom:4px;line-height:1.6}
.footer-trademark{margin-top:8px;padding-top:10px;border-top:1px solid rgba(255,255,255,.08)}

/* ===== Responsive ===== */
@media(max-width:1024px){
.article-layout{grid-template-columns:1fr}
.sidebar{position:static;display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.sidebar .widget{margin-bottom:0}
.featured-article{grid-template-columns:1fr}
.featured-thumb{min-height:180px}
.article-grid{grid-template-columns:repeat(2,1fr)}
.cert-nav-grid{grid-template-columns:1fr}
.footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:768px){
.section{padding:40px 0}
.section-title h2{font-size:22px}
.hero-content h1{font-size:24px}
.hero-content p{font-size:14px}
.nav-menu{display:none;position:fixed;top:64px;left:0;right:0;background:var(--white);flex-direction:column;padding:12px;box-shadow:var(--shadow-lg);max-height:calc(100vh - 64px);overflow-y:auto}
.nav-menu.active{display:flex}
.nav-menu>li{width:100%}
.nav-menu>li>a{line-height:44px;border-bottom:1px solid var(--border)}
.nav-dropdown{position:static;transform:none;opacity:1;visibility:visible;box-shadow:none;padding:0 0 0 20px;display:none}
.nav-menu>li:hover .nav-dropdown{display:block}
.nav-toggle{display:flex}
.article-grid{grid-template-columns:1fr}
.sidebar{grid-template-columns:1fr}
.footer-grid{grid-template-columns:1fr}
}
@media(max-width:480px){
.hero-content h1{font-size:20px}
.featured-article{grid-template-columns:1fr}
.featured-thumb{min-height:140px}
}