/* 全局重置与基础 */
*{margin:0;padding:0;box-sizing:border-box}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;background:#f5f7fa;color:#1a1a2e;line-height:1.6;transition:background .3s,color .3s}
body.dark{background:#0f0f1a;color:#e0e0e0}
a{color:#2a6df4;text-decoration:none;transition:color .3s}
a:hover{color:#1a4bbf}
img{max-width:100%;height:auto;display:block}
.container{max-width:1200px;margin:0 auto;padding:0 20px}
.section{padding:80px 0}
.section-title{font-size:2rem;font-weight:700;text-align:center;margin-bottom:30px;position:relative}
.section-title:after{content:'';display:block;width:60px;height:4px;background:linear-gradient(90deg,#2a6df4,#7b2ff7);margin:12px auto 0;border-radius:2px}
.card{background:#fff;border-radius:16px;padding:24px;box-shadow:0 4px 20px rgba(0,0,0,.06);transition:transform .3s,box-shadow .3s;backdrop-filter:blur(10px);background:rgba(255,255,255,.8)}
.dark .card{background:rgba(30,30,50,.8);box-shadow:0 4px 20px rgba(0,0,0,.3)}
.card:hover{transform:translateY(-4px);box-shadow:0 12px 40px rgba(0,0,0,.1)}
.btn{display:inline-block;padding:12px 28px;border-radius:50px;font-weight:600;border:none;cursor:pointer;transition:all .3s;background:linear-gradient(135deg,#2a6df4,#7b2ff7);color:#fff;text-align:center}
.btn:hover{transform:scale(1.05);box-shadow:0 8px 25px rgba(42,109,244,.4)}
.grid{display:grid;gap:30px}
.grid-2{grid-template-columns:repeat(auto-fit,minmax(300px,1fr))}
.grid-3{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.grid-4{grid-template-columns:repeat(auto-fit,minmax(220px,1fr))}
.flex-center{display:flex;align-items:center;justify-content:center}
.text-center{text-align:center}
.mt-20{margin-top:20px}
.mb-20{margin-bottom:20px}
/* 导航 */
header{position:fixed;top:0;left:0;width:100%;z-index:1000;background:rgba(255,255,255,.85);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border-bottom:1px solid rgba(0,0,0,.05);transition:background .3s}
.dark header{background:rgba(15,15,26,.85);border-bottom:1px solid rgba(255,255,255,.05)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:70px;padding:0 20px;max-width:1200px;margin:0 auto}
.logo{font-size:1.6rem;font-weight:800;background:linear-gradient(135deg,#2a6df4,#7b2ff7);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.nav-menu{display:flex;gap:24px;list-style:none}
.nav-menu a{font-weight:500;color:#1a1a2e;padding:6px 0;position:relative}
.dark .nav-menu a{color:#e0e0e0}
.nav-menu a:after{content:'';position:absolute;bottom:0;left:0;width:0;height:2px;background:#2a6df4;transition:width .3s}
.nav-menu a:hover:after{width:100%}
.nav-actions{display:flex;gap:12px;align-items:center}
.theme-toggle,.search-toggle,.menu-toggle{background:none;border:none;font-size:1.4rem;cursor:pointer;color:#1a1a2e;padding:6px;border-radius:8px;transition:background .3s}
.dark .theme-toggle,.dark .search-toggle,.dark .menu-toggle{color:#e0e0e0}
.theme-toggle:hover,.search-toggle:hover,.menu-toggle:hover{background:rgba(0,0,0,.05)}
.dark .theme-toggle:hover,.dark .search-toggle:hover,.dark .menu-toggle:hover{background:rgba(255,255,255,.05)}
.menu-toggle{display:none}
@media(max-width:768px){
    .nav-menu{display:none;position:absolute;top:70px;left:0;width:100%;background:rgba(255,255,255,.98);backdrop-filter:blur(20px);flex-direction:column;padding:20px;gap:16px;box-shadow:0 20px 40px rgba(0,0,0,.1)}
    .dark .nav-menu{background:rgba(15,15,26,.98)}
    .nav-menu.open{display:flex}
    .menu-toggle{display:block}
}
/* 搜索框 */
.search-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,.5);z-index:2000;display:none;justify-content:center;align-items:flex-start;padding-top:120px}
.search-overlay.active{display:flex}
.search-box{background:#fff;padding:30px;border-radius:16px;width:90%;max-width:500px;box-shadow:0 20px 60px rgba(0,0,0,.2)}
.dark .search-box{background:#1a1a2e}
.search-box input{width:100%;padding:14px 18px;border:2px solid #e0e0e0;border-radius:50px;font-size:1rem;outline:none;transition:border .3s}
.dark .search-box input{background:#2a2a3e;border-color:#3a3a4e;color:#fff}
.search-box input:focus{border-color:#2a6df4}
.search-results{margin-top:16px;max-height:300px;overflow-y:auto}
.search-results a{display:block;padding:10px 0;border-bottom:1px solid #eee;color:#333}
.dark .search-results a{color:#ccc;border-color:#2a2a3e}
/* Hero Banner */
.hero{background:linear-gradient(135deg,#1a1a2e 0%,#16213e 50%,#0f3460 100%);color:#fff;padding:140px 0 80px;position:relative;overflow:hidden}
.hero:after{content:'';position:absolute;top:-50%;left:-50%;width:200%;height:200%;background:radial-gradient(circle at 30% 50%,rgba(42,109,244,.15) 0%,transparent 60%);pointer-events:none}
.hero .container{position:relative;z-index:2}
.hero-grid{display:grid;grid-template-columns:1fr 1fr;gap:50px;align-items:center}
@media(max-width:768px){.hero-grid{grid-template-columns:1fr;text-align:center}}
.hero h1{font-size:2.8rem;font-weight:800;line-height:1.2;margin-bottom:20px}
.hero h1 span{background:linear-gradient(135deg,#2a6df4,#7b2ff7);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero p{font-size:1.1rem;color:rgba(255,255,255,.7);margin-bottom:30px;max-width:500px}
.hero-buttons{display:flex;gap:16px;flex-wrap:wrap}
.hero-buttons .btn-outline{background:transparent;border:2px solid rgba(255,255,255,.3);color:#fff}
.hero-buttons .btn-outline:hover{background:rgba(255,255,255,.1);border-color:#fff}
.hero-image{display:flex;justify-content:center;align-items:center}
.hero-image svg{width:100%;max-width:400px;height:auto;border-radius:24px;box-shadow:0 20px 60px rgba(0,0,0,.3)}
/* 面包屑 */
.breadcrumb{padding:16px 0;font-size:.9rem;color:#666;background:#f5f7fa;border-bottom:1px solid #e0e0e0}
.dark .breadcrumb{background:#0f0f1a;color:#aaa;border-color:#2a2a3e}
.breadcrumb a{color:#2a6df4}
.breadcrumb span{margin:0 6px;color:#999}
/* 轮播 */
.carousel{position:relative;overflow:hidden;border-radius:16px;background:#eee;min-height:300px}
.dark .carousel{background:#1a1a2e}
.carousel-inner{display:flex;transition:transform .5s ease}
.carousel-item{min-width:100%;padding:40px;display:flex;align-items:center;justify-content:center;flex-direction:column;text-align:center}
.carousel-controls{position:absolute;top:50%;width:100%;display:flex;justify-content:space-between;transform:translateY(-50%);padding:0 16px;pointer-events:none}
.carousel-controls button{pointer-events:auto;background:rgba(255,255,255,.8);border:none;border-radius:50%;width:44px;height:44px;font-size:1.4rem;cursor:pointer;transition:background .3s;box-shadow:0 4px 12px rgba(0,0,0,.1)}
.dark .carousel-controls button{background:rgba(30,30,50,.8);color:#fff}
.carousel-controls button:hover{background:#fff}
.carousel-dots{display:flex;justify-content:center;gap:8px;padding:16px 0}
.carousel-dots span{width:10px;height:10px;border-radius:50%;background:#ccc;cursor:pointer;transition:background .3s}
.carousel-dots span.active{background:#2a6df4}
/* FAQ */
.faq-item{border-bottom:1px solid #e0e0e0;padding:16px 0;cursor:pointer}
.dark .faq-item{border-color:#2a2a3e}
.faq-question{font-weight:600;display:flex;justify-content:space-between;align-items:center}
.faq-question:after{content:'+';font-size:1.4rem;transition:transform .3s}
.faq-item.open .faq-question:after{content:'−'}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .4s ease,padding .3s;padding-top:0;color:#555}
.dark .faq-answer{color:#aaa}
.faq-item.open .faq-answer{max-height:500px;padding-top:12px}
/* HowTo */
.howto-step{display:flex;gap:20px;margin-bottom:24px;align-items:flex-start}
.howto-step-num{width:40px;height:40px;border-radius:50%;background:linear-gradient(135deg,#2a6df4,#7b2ff7);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:700;flex-shrink:0}
.howto-step-content h4{font-size:1.1rem;margin-bottom:6px}
/* 数字动画 */
.stat-number{font-size:2.4rem;font-weight:800;background:linear-gradient(135deg,#2a6df4,#7b2ff7);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
/* 滚动动画 */
.fade-up{opacity:0;transform:translateY(30px);transition:opacity .6s ease,transform .6s ease}
.fade-up.visible{opacity:1;transform:translateY(0)}
/* 返回顶部 */
.back-to-top{position:fixed;bottom:30px;right:30px;width:50px;height:50px;border-radius:50%;background:linear-gradient(135deg,#2a6df4,#7b2ff7);color:#fff;border:none;font-size:1.5rem;cursor:pointer;box-shadow:0 8px 25px rgba(42,109,244,.4);display:none;z-index:999;transition:all .3s}
.back-to-top.show{display:block}
.back-to-top:hover{transform:scale(1.1)}
/* 页脚 */
footer{background:#1a1a2e;color:rgba(255,255,255,.7);padding:60px 0 30px}
footer a{color:rgba(255,255,255,.6)}
footer a:hover{color:#fff}
.footer-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:40px;margin-bottom:40px}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding-top:20px;display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;font-size:.85rem}
.footer-qr{display:flex;gap:20px;margin-top:16px}
.footer-qr svg{width:80px;height:80px;border-radius:8px;background:#fff;padding:8px}
/* 文章卡片 */
.article-card{padding:0;overflow:hidden}
.article-card .card-body{padding:20px}
.article-card h3{font-size:1.2rem;margin-bottom:8px}
.article-card .meta{font-size:.85rem;color:#888;margin-bottom:8px}
.article-card p{font-size:.95rem;color:#555}
.dark .article-card p{color:#aaa}
.read-more{color:#2a6df4;font-weight:600;display:inline-block;margin-top:8px}
/* 友情链接 */
.friend-links{display:flex;flex-wrap:wrap;gap:12px;justify-content:center;padding:20px 0}
.friend-links a{color:#666;font-size:.9rem}
.dark .friend-links a{color:#aaa}
/* 响应式 */
@media(max-width:480px){
    .hero h1{font-size:2rem}
    .section{padding:50px 0}
    .section-title{font-size:1.5rem}
}