/* ============================================================
   NUC_NetWork&BIG Data_lab · 招新站点公共样式
   三页共用：index.html（导航） / intro.html（实验室介绍） / learn.html（学习）
   ============================================================ */
:root{
  --bg:#070b16;
  --bg-soft:#0b1120;
  --panel:rgba(255,255,255,.04);
  --border:rgba(255,255,255,.09);
  --cyan:#22d3ee;
  --blue:#3b82f6;
  --violet:#8b5cf6;
  --pink:#ec4899;
  --green:#34d399;
  --amber:#fbbf24;
  --text:#e5e9f4;
  --muted:#8b93a7;
  --grad:linear-gradient(120deg,#22d3ee,#3b82f6 45%,#8b5cf6);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
section[id]{scroll-margin-top:128px}
.tut[id]{scroll-margin-top:96px}
body{
  font-family:'Noto Sans SC','Microsoft YaHei',system-ui,sans-serif;
  background:var(--bg);
  color:var(--text);
  line-height:1.7;
  overflow-x:hidden;
}
::selection{background:rgba(34,211,238,.35)}
::-webkit-scrollbar{width:10px}
::-webkit-scrollbar-track{background:#0a0f1c}
::-webkit-scrollbar-thumb{background:linear-gradient(#22d3ee,#8b5cf6);border-radius:10px}

a{color:inherit;text-decoration:none}
.container{width:min(1180px,92%);margin:0 auto}

/* 背景装饰 */
.bg-fixed{position:fixed;inset:0;z-index:-2;background:radial-gradient(1200px 600px at 80% -10%,rgba(59,130,246,.15),transparent 60%),radial-gradient(900px 500px at 0% 30%,rgba(139,92,246,.12),transparent 60%),radial-gradient(800px 600px at 100% 70%,rgba(34,211,238,.10),transparent 60%),var(--bg)}
.bg-grid{position:fixed;inset:0;z-index:-1;background-image:linear-gradient(rgba(255,255,255,.03) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.03) 1px,transparent 1px);background-size:56px 56px;mask-image:radial-gradient(ellipse at 50% 0%,#000 0%,transparent 75%)}

/* 导航（三页共用，current 高亮） */
nav{position:fixed;top:0;left:0;right:0;z-index:100;transition:.4s;padding:16px 0}
nav.scrolled{background:rgba(7,11,22,.78);backdrop-filter:blur(22px) saturate(150%);border-bottom:1px solid rgba(255,255,255,.07);padding:9px 0;box-shadow:0 12px 44px rgba(0,0,0,.45)}
.nav-inner{display:flex;align-items:center;justify-content:space-between}
.logo{display:flex;align-items:center;gap:10px;font-weight:900;font-size:16.5px;letter-spacing:.5px}
.logo-badge{width:36px;height:36px;border-radius:50%;background:var(--grad);display:grid;place-items:center;overflow:hidden;flex:none;box-shadow:0 0 20px rgba(34,211,238,.5);border:2px solid rgba(255,255,255,.35)}
.logo-badge img{width:100%;height:100%;object-fit:cover}
.nav-links{display:flex;gap:6px;list-style:none}
.nav-links a{font-size:13.5px;color:var(--muted);transition:.3s;position:relative;padding:9px 16px;border-radius:999px;display:flex;align-items:center;gap:7px;font-weight:600;border:1px solid transparent}
.nav-links a i{font-size:14px;opacity:.85;transition:.3s}
.nav-links a:hover{color:#fff;background:rgba(255,255,255,.06)}
.nav-links a:hover i{color:var(--cyan);opacity:1}
.nav-links a.active{color:#fff;background:linear-gradient(120deg,rgba(34,211,238,.17),rgba(139,92,246,.17));border-color:rgba(34,211,238,.32);box-shadow:0 0 22px rgba(34,211,238,.14),inset 0 0 14px rgba(34,211,238,.05)}
.nav-links a.active i{color:var(--cyan)}
.nav-cta{background:var(--grad);border:none;color:#fff;font-weight:700;font-size:13px;padding:10px 20px;border-radius:999px;cursor:pointer;transition:.3s;box-shadow:0 4px 18px rgba(59,130,246,.4);font-family:inherit}
.nav-cta:hover{transform:translateY(-2px);box-shadow:0 6px 26px rgba(34,211,238,.5)}
.burger{display:none;background:none;border:none;color:var(--text);font-size:24px;cursor:pointer}

/* Hero */
.hero{min-height:100vh;display:flex;align-items:center;justify-content:center;text-align:center;position:relative;padding-top:80px}
#network{position:absolute;inset:0;z-index:-1}
.hero-logo{width:108px;height:108px;margin:0 auto 26px;border-radius:50%;overflow:hidden;border:3px solid rgba(34,211,238,.5);box-shadow:0 0 40px rgba(34,211,238,.45),0 0 90px rgba(139,92,246,.3);animation:rise 1s ease both;background:#fff}
.hero-logo img{width:100%;height:100%;object-fit:cover}
.hero-title{font-size:clamp(38px,6.5vw,78px);font-weight:900;letter-spacing:1.5px;line-height:1.15;background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;animation:rise 1s ease both}
.hero-sub{font-family:'JetBrains Mono',monospace;font-size:clamp(14px,2vw,20px);color:var(--muted);letter-spacing:6px;margin-top:18px;animation:rise 1s .15s ease both}
.hero-tag{margin-top:26px;display:inline-flex;gap:10px;align-items:center;padding:9px 22px;border:1px solid var(--border);border-radius:999px;background:var(--panel);backdrop-filter:blur(8px);font-size:14px;color:#c9d2e6;animation:rise 1s .3s ease both}
.hero-tag .dot{width:8px;height:8px;border-radius:50%;background:var(--green);box-shadow:0 0 10px var(--green);animation:pulse 2s infinite}
.hero-slogan{margin:26px auto 0;max-width:680px;font-size:18px;color:#cdd5e6;animation:rise 1s .45s ease both}
.hero-slogan b{color:#fff}
.hero-btns{margin-top:42px;display:flex;gap:18px;justify-content:center;flex-wrap:wrap;animation:rise 1s .6s ease both}
.btn{display:inline-flex;align-items:center;gap:8px;padding:15px 34px;border-radius:999px;font-size:16px;font-weight:700;cursor:pointer;transition:.3s;border:none;font-family:inherit}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 8px 30px rgba(34,211,238,.35)}
.btn-primary:hover{transform:translateY(-3px);box-shadow:0 12px 40px rgba(59,130,246,.5)}
.btn-ghost{background:rgba(255,255,255,.05);color:var(--text);border:1px solid var(--border)}
.btn-ghost:hover{background:rgba(255,255,255,.1);transform:translateY(-3px)}
.scroll-hint{position:absolute;bottom:30px;left:50%;transform:translateX(-50%);color:var(--muted);font-size:12px;letter-spacing:3px;display:flex;flex-direction:column;align-items:center;gap:8px;animation:rise 1s .9s ease both}
.scroll-hint .mouse{width:24px;height:38px;border:2px solid var(--muted);border-radius:14px;position:relative}
.scroll-hint .mouse::after{content:'';position:absolute;top:7px;left:50%;transform:translateX(-50%);width:4px;height:8px;border-radius:4px;background:var(--cyan);animation:wheel 1.6s infinite}

/* 通用区块 */
section{padding:110px 0;position:relative}
.section-head{text-align:center;margin-bottom:64px}
.sec-no{font-family:'JetBrains Mono',monospace;color:var(--cyan);font-size:14px;letter-spacing:4px;margin-bottom:10px}
.sec-title{font-size:clamp(28px,4.5vw,46px);font-weight:900;letter-spacing:1px}
.sec-title span{background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.sec-sub{color:var(--muted);margin-top:12px;font-size:16px}

/* 卡片通用 */
.card{background:var(--panel);border:1px solid var(--border);border-radius:18px;padding:28px;backdrop-filter:blur(10px);transition:.4s;position:relative;overflow:hidden}
.card::before{content:'';position:absolute;inset:0;background:var(--grad);opacity:0;transition:.4s}
.card:hover{transform:translateY(-6px);border-color:rgba(34,211,238,.4);box-shadow:0 20px 50px rgba(0,0,0,.5)}
.card:hover::before{opacity:.06}

/* 动画 */
@keyframes rise{from{opacity:0;transform:translateY(34px)}to{opacity:1;transform:translateY(0)}}
@keyframes fadeUp{from{opacity:0;transform:translateY(26px)}to{opacity:1;transform:translateY(0)}}
@keyframes pulse{0%,100%{opacity:1;transform:scale(1)}50%{opacity:.4;transform:scale(.8)}}
@keyframes wheel{0%{opacity:1;transform:translate(-50%,0)}100%{opacity:0;transform:translate(-50%,14px)}}
@keyframes shine{0%,100%{transform:rotate(20deg) translateX(-30%)}50%{transform:rotate(20deg) translateX(220%)}}
@keyframes floaty{0%,100%{transform:translateY(0)}50%{transform:translateY(-12px)}}
.reveal{opacity:0;transform:translateY(36px);transition:opacity .8s ease,transform .8s ease}
.reveal.visible{opacity:1;transform:none}
.reveal.d1{transition-delay:.1s}.reveal.d2{transition-delay:.2s}.reveal.d3{transition-delay:.3s}.reveal.d4{transition-delay:.4s}

footer{border-top:1px solid var(--border);padding:40px 0;text-align:center;color:var(--muted);font-size:14px;background:rgba(7,11,22,.6)}
footer .footer-logo{font-weight:900;font-size:16px;color:var(--text);margin-bottom:8px}

/* ============================================================
   导航首页 · 模块入口大卡片
   ============================================================ */
.module-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.module-card{padding:44px 34px;border-radius:24px;background:var(--panel);border:1px solid var(--border);text-align:center;position:relative;overflow:hidden;transition:.45s;cursor:pointer;display:block}
.module-card::before{content:'';position:absolute;top:-70px;right:-70px;width:220px;height:220px;border-radius:50%;opacity:0;transition:.45s;background:radial-gradient(circle,rgba(34,211,238,.35),transparent 70%)}
.module-card:hover{transform:translateY(-10px);border-color:rgba(34,211,238,.5);box-shadow:0 24px 60px rgba(0,0,0,.55)}
.module-card:hover::before{opacity:1}
.module-card .m-ico{width:84px;height:84px;margin:0 auto 22px;border-radius:24px;display:grid;place-items:center;font-size:38px;color:#fff;animation:floaty 4s ease-in-out infinite}
.module-card:nth-child(1) .m-ico{background:linear-gradient(135deg,#22d3ee,#3b82f6);box-shadow:0 12px 34px rgba(34,211,238,.4)}
.module-card:nth-child(2) .m-ico{background:linear-gradient(135deg,#3b82f6,#8b5cf6);box-shadow:0 12px 34px rgba(139,92,246,.4)}
.module-card:nth-child(3) .m-ico{background:linear-gradient(135deg,#8b5cf6,#ec4899);box-shadow:0 12px 34px rgba(236,72,153,.4)}
.module-card h3{font-size:24px;font-weight:900}
.module-card .en{font-family:'JetBrains Mono',monospace;color:var(--muted);font-size:12px;letter-spacing:2.5px;margin-top:4px}
.module-card p{color:var(--muted);font-size:14.5px;margin-top:16px;line-height:1.9}
.module-card .m-tags{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-top:18px}
.module-card .m-tags span{font-size:11.5px;padding:4px 12px;border-radius:999px;background:rgba(255,255,255,.05);border:1px solid var(--border);color:#c9d2e6}
.module-card .m-go{display:inline-flex;align-items:center;gap:8px;margin-top:26px;padding:11px 26px;border-radius:999px;background:var(--grad);color:#fff;font-size:14px;font-weight:700;transition:.3s;box-shadow:0 8px 24px rgba(59,130,246,.35)}
.module-card:hover .m-go{transform:translateY(-2px);box-shadow:0 12px 30px rgba(34,211,238,.5)}

/* ============================================================
   学习页
   ============================================================ */
.learn-tabs{display:flex;justify-content:center;gap:14px;margin-bottom:54px;flex-wrap:wrap}
.learn-tab{position:relative;display:inline-flex;align-items:center;gap:10px;padding:15px 38px;border-radius:999px;background:var(--panel);border:1px solid var(--border);color:var(--muted);font-size:16px;font-weight:700;cursor:pointer;transition:.35s;font-family:inherit;letter-spacing:.5px}
.learn-tab i{font-size:18px}
.learn-tab:hover{color:var(--text);border-color:rgba(34,211,238,.4);transform:translateY(-2px)}
.learn-tab.active{background:var(--grad);color:#fff;box-shadow:0 8px 30px rgba(59,130,246,.45);transform:translateY(-2px)}
.learn-panel{display:none}
.learn-panel.active{display:block;animation:fadeUp .5s ease}

/* 方向/语言大章节 */
.sec-block{padding:44px;border-radius:24px;background:var(--panel);border:1px solid var(--border);margin-bottom:40px;position:relative;overflow:hidden}
.sec-block::before{content:'';position:absolute;top:0;left:0;right:0;height:3px;background:var(--grad)}
.sec-block-head{display:flex;align-items:center;gap:18px;margin-bottom:18px}
.sec-block-head .sb-ico{width:62px;height:62px;flex:none;border-radius:18px;display:grid;place-items:center;font-size:28px;color:#fff;font-family:'JetBrains Mono',monospace;font-weight:900}
.sec-block.c-block .sb-ico{background:linear-gradient(135deg,#38bdf8,#2563eb);box-shadow:0 10px 26px rgba(37,99,235,.4)}
.sec-block.py-block .sb-ico{background:linear-gradient(135deg,#facc15,#f97316);box-shadow:0 10px 26px rgba(249,115,22,.4)}
.sec-block.web-block .sb-ico{background:linear-gradient(135deg,#22d3ee,#3b82f6);box-shadow:0 10px 26px rgba(34,211,238,.4)}
.sec-block.rev-block .sb-ico{background:linear-gradient(135deg,#3b82f6,#8b5cf6);box-shadow:0 10px 26px rgba(139,92,246,.4)}
.sec-block.misc-block .sb-ico{background:linear-gradient(135deg,#34d399,#22d3ee);box-shadow:0 10px 26px rgba(52,211,153,.4)}
.sec-block.pwn-block .sb-ico{background:linear-gradient(135deg,#ec4899,#f97316);box-shadow:0 10px 26px rgba(236,72,153,.4)}
.sec-block-head h3{font-size:24px;font-weight:900}
.sec-block-head .en{font-family:'JetBrains Mono',monospace;font-size:12px;color:var(--muted);letter-spacing:2px}
.sec-block .intro{color:#c6cfe1;font-size:15px;margin-bottom:24px}
.sec-block .intro b{color:#fff}
.sec-block h4{font-size:17px;margin:26px 0 14px;display:flex;align-items:center;gap:8px}
.sec-block h4 i{color:var(--cyan)}

/* 知识清单 */
.klist{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.kitem{display:flex;gap:12px;align-items:flex-start;padding:14px 16px;border-radius:12px;background:rgba(255,255,255,.03);border:1px solid var(--border);font-size:14px;color:#c6cfe1;transition:.3s}
.kitem:hover{border-color:rgba(34,211,238,.4);background:rgba(34,211,238,.05);transform:translateX(4px)}
.kitem i{color:var(--cyan);margin-top:4px}
.kitem b{color:#fff}

/* 学习路线步骤 */
.learn-steps{display:flex;flex-direction:column;gap:12px;margin:6px 0 10px}
.lstep{display:flex;gap:14px;align-items:flex-start;font-size:14px;color:#c6cfe1}
.lstep .sn{flex:none;width:26px;height:26px;border-radius:8px;background:rgba(34,211,238,.14);border:1px solid rgba(34,211,238,.35);display:grid;place-items:center;font-family:'JetBrains Mono',monospace;font-size:12px;font-weight:700;color:var(--cyan);margin-top:2px}
.lstep b{color:#fff;font-weight:600}

/* 练习题 + WP */
.chal-title{display:flex;align-items:center;gap:8px;font-size:14px;color:var(--muted);letter-spacing:2px;margin-bottom:14px}
.chal-title i{color:var(--amber)}
.challenge{display:flex;align-items:center;flex-wrap:wrap;gap:10px;padding:14px 18px;border-radius:12px;background:rgba(7,11,22,.5);border:1px solid var(--border);margin-bottom:10px;transition:.3s}
.challenge:hover{border-color:rgba(251,191,36,.5);transform:translateX(4px)}
.chal-src{flex:none;font-size:11px;font-weight:700;padding:3px 10px;border-radius:999px;letter-spacing:.5px}
.chal-src.buu{background:rgba(34,211,238,.15);color:var(--cyan);border:1px solid rgba(34,211,238,.4)}
.chal-src.adworld{background:rgba(139,92,246,.15);color:#a78bfa;border:1px solid rgba(139,92,246,.4)}
.chal-src.luogu{background:rgba(74,222,128,.13);color:#4ade80;border:1px solid rgba(74,222,128,.35)}
.chal-src.leetcode{background:rgba(251,191,36,.13);color:var(--amber);border:1px solid rgba(251,191,36,.35)}
.challenge b{font-size:14px;color:#eaf0fb}
.chal-type{font-size:11px;color:var(--muted);padding:2px 10px;border-radius:999px;background:rgba(255,255,255,.06)}
.chal-diff{margin-left:auto;font-family:'JetBrains Mono',monospace;font-size:12px;color:var(--amber);letter-spacing:1px}

/* WP 折叠 */
.wp{margin:4px 0 18px;border:1px solid rgba(34,211,238,.28);border-radius:14px;background:rgba(34,211,238,.04);overflow:hidden}
.wp>summary{list-style:none;cursor:pointer;padding:13px 18px;display:flex;align-items:center;gap:10px;font-size:14px;font-weight:700;color:var(--cyan);transition:.3s;user-select:none}
.wp>summary::-webkit-details-marker{display:none}
.wp>summary:hover{background:rgba(34,211,238,.07)}
.wp>summary::before{content:'▸';transition:.3s;font-size:12px}
.wp[open]>summary::before{transform:rotate(90deg)}
.wp-body{padding:6px 22px 20px;font-size:14.5px;color:#c6cfe1}
.wp-body p{margin:10px 0}
.wp-body b{color:#fff}
.wp-body .step{display:flex;gap:10px;margin:12px 0}
.wp-body .step .n{flex:none;width:22px;height:22px;border-radius:7px;background:var(--grad);display:grid;place-items:center;font-size:12px;font-weight:900;color:#fff;margin-top:2px}
.wp-body pre{background:#0a0f1c;border:1px solid var(--border);border-radius:10px;padding:14px 16px;margin:10px 0;overflow-x:auto;font-family:'JetBrains Mono',Consolas,monospace;font-size:13px;line-height:1.7;color:#a5f3fc}
.wp-body code{font-family:'JetBrains Mono',Consolas,monospace;background:rgba(34,211,238,.12);color:#7dd3fc;padding:1px 7px;border-radius:6px;font-size:13px}
.wp-body .flag{display:inline-block;margin-top:8px;padding:4px 14px;border-radius:8px;background:rgba(52,211,153,.12);border:1px dashed rgba(52,211,153,.5);color:#6ee7b7;font-family:'JetBrains Mono',monospace;font-size:13px}

/* 资源条 */
.res-bar{display:flex;flex-wrap:wrap;justify-content:center;gap:14px;margin-top:14px}
.res-btn{display:inline-flex;align-items:center;gap:8px;padding:12px 24px;border-radius:999px;background:var(--panel);border:1px solid var(--border);color:#c9d2e6;font-size:14px;font-weight:600;transition:.3s;cursor:pointer}
.res-btn:hover{transform:translateY(-3px);border-color:rgba(34,211,238,.5);color:#fff;box-shadow:0 10px 26px rgba(34,211,238,.18)}
.res-btn i{color:var(--cyan)}
.learn-tip{text-align:center;color:var(--muted);font-size:13.5px;margin-top:44px;line-height:2}
.learn-tip b{color:#22d3ee}

/* 页内小导航（方向锚点） */
.sub-nav{display:flex;justify-content:center;gap:10px;flex-wrap:wrap;margin:-28px 0 46px}
.sub-nav a{font-size:13px;padding:8px 18px;border-radius:999px;background:var(--panel);border:1px solid var(--border);color:var(--muted);transition:.3s}
.sub-nav a:hover{color:#fff;border-color:rgba(34,211,238,.5);background:rgba(34,211,238,.08)}

/* ============================================================
   详情页 · 教程正文
   ============================================================ */
.tut{padding:42px;border-radius:20px;background:var(--panel);border:1px solid var(--border);margin-bottom:30px;position:relative;overflow:hidden}
.tut h3{font-size:20px;margin:32px 0 14px;display:flex;align-items:center;gap:10px;color:#fff}
.tut h3:first-child{margin-top:0}
.tut h3 i{color:var(--cyan)}
.tut h4{font-size:16px;margin:20px 0 10px;color:#c9d2e6}
.tut p{color:#c6cfe1;font-size:15px;margin:10px 0}
.tut ul,.tut ol{margin:10px 0 10px 24px;color:#c6cfe1;font-size:15px}
.tut li{margin:7px 0}
.tut b{color:#fff}
.tut code{font-family:'JetBrains Mono',Consolas,monospace;background:rgba(34,211,238,.12);color:#7dd3fc;padding:1px 7px;border-radius:6px;font-size:13.5px}
.tut .note{border-left:3px solid var(--amber);background:rgba(251,191,36,.07);padding:12px 18px;border-radius:0 10px 10px 0;margin:16px 0;font-size:14px;color:#e8d5a8;line-height:1.9}
.tut table{width:100%;border-collapse:collapse;margin:14px 0;font-size:14px}
.tut th,.tut td{border:1px solid var(--border);padding:10px 14px;text-align:left;color:#c6cfe1}
.tut th{background:rgba(34,211,238,.08);color:#7dd3fc;font-weight:700}

/* 题目直达链接按钮 */
.chal-link{display:inline-flex;align-items:center;gap:6px;margin-left:auto;font-size:12.5px;font-weight:700;padding:6px 16px;border-radius:999px;background:linear-gradient(120deg,rgba(34,211,238,.15),rgba(139,92,246,.15));border:1px solid rgba(34,211,238,.4);color:#7dd3fc;transition:.3s;cursor:pointer;white-space:nowrap}
.chal-link:hover{background:var(--grad);color:#fff;transform:translateY(-2px);border-color:transparent}

/* 学习中心方向入口网格 */
.dir-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}

/* ============================================================
   学习页增强组件：统计条 / 路线时间轴 / FAQ / 对比表
   ============================================================ */
/* 数据一览统计条 */
.stats-bar{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin:0 0 46px}
.stat{text-align:center;padding:26px 14px;border-radius:18px;background:var(--panel);border:1px solid var(--border);transition:.35s;position:relative;overflow:hidden}
.stat::after{content:'';position:absolute;bottom:0;left:0;right:0;height:2px;background:var(--grad);transform:scaleX(0);transition:.4s}
.stat:hover{transform:translateY(-5px);border-color:rgba(34,211,238,.45)}
.stat:hover::after{transform:scaleX(1)}
.stat .num{font-family:'JetBrains Mono',monospace;font-size:clamp(26px,3.2vw,34px);font-weight:900;background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;line-height:1.2}
.stat .num small{font-size:14px;-webkit-text-fill-color:var(--muted);color:var(--muted);margin-left:2px}
.stat .lbl{color:var(--muted);font-size:13px;margin-top:8px;letter-spacing:.5px}

/* 学习路线时间轴 */
.tl{position:relative;margin:12px 0 6px;padding-left:34px}
.tl::before{content:'';position:absolute;left:9px;top:8px;bottom:8px;width:2px;background:linear-gradient(180deg,var(--cyan),var(--blue),var(--violet))}
.tl-item{position:relative;padding:0 0 28px 20px}
.tl-item:last-child{padding-bottom:0}
.tl-item::before{content:'';position:absolute;left:-31px;top:5px;width:13px;height:13px;border-radius:50%;background:var(--bg);border:2.5px solid var(--cyan);box-shadow:0 0 14px rgba(34,211,238,.65)}
.tl-item:nth-child(2n)::before{border-color:var(--violet);box-shadow:0 0 14px rgba(139,92,246,.65)}
.tl-item h4{font-size:16.5px;color:#fff;display:flex;align-items:center;gap:9px}
.tl-item h4 i{color:var(--cyan)}
.tl-item .tl-time{font-family:'JetBrains Mono',monospace;font-size:11.5px;color:var(--cyan);letter-spacing:1.5px;margin-left:auto;flex:none}
.tl-item p{color:var(--muted);font-size:14px;margin-top:5px;line-height:1.85}
.tl-item p b{color:#c9d2e6}

/* FAQ 折叠面板 */
.faq{max-width:840px;margin:0 auto}
.faq details{background:var(--panel);border:1px solid var(--border);border-radius:14px;margin-bottom:12px;overflow:hidden;transition:.3s}
.faq details[open]{border-color:rgba(34,211,238,.42);background:rgba(34,211,238,.04);box-shadow:0 8px 30px rgba(34,211,238,.07)}
.faq summary{list-style:none;cursor:pointer;padding:17px 22px;display:flex;align-items:center;gap:12px;font-size:15.5px;font-weight:700;color:#eaf0fb;user-select:none;transition:.3s}
.faq summary::-webkit-details-marker{display:none}
.faq summary:hover{color:#fff}
.faq summary i{color:var(--cyan);font-size:18px}
.faq summary::after{content:'▾';margin-left:auto;color:var(--cyan);transition:.3s;font-size:13px}
.faq details[open] summary::after{transform:rotate(180deg)}
.faq .faq-a{padding:0 22px 20px;color:var(--muted);font-size:14px;line-height:2}
.faq .faq-a b{color:#fff}

/* 方向对比表（网安页） */
.cmp-table{width:100%;border-collapse:collapse;margin:8px 0 4px;font-size:14px}
.cmp-table th,.cmp-table td{border:1px solid var(--border);padding:12px 16px;text-align:left;color:#c6cfe1}
.cmp-table th{background:rgba(34,211,238,.08);color:#7dd3fc;font-weight:700;white-space:nowrap}
.cmp-table td b{color:#fff}

/* ============================================================
   实验室介绍页：吸顶页内导航 / 日常网格 / 招新流程
   ============================================================ */
.subnav-sticky{position:fixed;top:66px;left:50%;right:auto;transform:translateX(-50%);z-index:90;display:flex;gap:4px;padding:7px;border-radius:999px;background:rgba(7,11,22,.72);backdrop-filter:blur(18px) saturate(150%);border:1px solid rgba(255,255,255,.08);box-shadow:0 10px 34px rgba(0,0,0,.4);max-width:94vw;overflow-x:auto;scrollbar-width:none;transition:.35s}
.subnav-sticky::-webkit-scrollbar{display:none}
.subnav-sticky a{white-space:nowrap;font-size:12.5px;padding:7px 15px;border-radius:999px;color:var(--muted);transition:.3s;font-weight:600}
.subnav-sticky a:hover{color:#fff;background:rgba(255,255,255,.07)}
.subnav-sticky a.active{color:#fff;background:linear-gradient(120deg,rgba(34,211,238,.18),rgba(139,92,246,.18));border:1px solid rgba(34,211,238,.35)}
nav.scrolled~.subnav-sticky{top:58px}
@media(max-width:960px){.subnav-sticky{top:57px;justify-content:flex-start;border-radius:14px}}

/* 实验室日常 4 卡 */
.life-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.life-card{text-align:center;padding:32px 20px;border-radius:18px;background:var(--panel);border:1px solid var(--border);transition:.35s;position:relative;overflow:hidden}
.life-card::before{content:'';position:absolute;top:-50px;right:-50px;width:140px;height:140px;border-radius:50%;background:radial-gradient(circle,rgba(34,211,238,.25),transparent 70%);opacity:0;transition:.4s}
.life-card:hover{transform:translateY(-6px);border-color:rgba(34,211,238,.5)}
.life-card:hover::before{opacity:1}
.life-card .l-ico{width:64px;height:64px;margin:0 auto 16px;border-radius:18px;display:grid;place-items:center;font-size:28px;color:#fff}
.life-card:nth-child(1) .l-ico{background:linear-gradient(135deg,#22d3ee,#3b82f6);box-shadow:0 10px 26px rgba(34,211,238,.4)}
.life-card:nth-child(2) .l-ico{background:linear-gradient(135deg,#3b82f6,#8b5cf6);box-shadow:0 10px 26px rgba(139,92,246,.4)}
.life-card:nth-child(3) .l-ico{background:linear-gradient(135deg,#8b5cf6,#ec4899);box-shadow:0 10px 26px rgba(236,72,153,.4)}
.life-card:nth-child(4) .l-ico{background:linear-gradient(135deg,#34d399,#22d3ee);box-shadow:0 10px 26px rgba(52,211,153,.4)}
.life-card h4{font-size:17px}
.life-card p{color:var(--muted);font-size:13.5px;margin-top:8px;line-height:1.85}

/* 招新流程步骤 */
.step-flow{display:grid;grid-template-columns:repeat(4,1fr);gap:22px;counter-reset:sf}
.flow-card{text-align:center;padding:34px 22px;border-radius:18px;background:var(--panel);border:1px solid var(--border);position:relative;transition:.35s}
.flow-card:hover{transform:translateY(-6px);border-color:rgba(34,211,238,.45)}
.flow-card .f-num{font-family:'JetBrains Mono',monospace;font-size:42px;font-weight:900;line-height:1;background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;opacity:.9}
.flow-card h4{font-size:17px;margin-top:10px}
.flow-card p{color:var(--muted);font-size:13.5px;margin-top:8px;line-height:1.85}
.flow-arrow{position:absolute;top:50%;right:-18px;transform:translateY(-50%);color:var(--cyan);font-size:20px;z-index:2;text-shadow:0 0 12px rgba(34,211,238,.6)}
.flow-card:last-child .flow-arrow{display:none}
@media(max-width:960px){.life-grid,.step-flow{grid-template-columns:repeat(2,1fr)}.flow-arrow{display:none}}
@media(max-width:560px){.life-grid,.step-flow{grid-template-columns:1fr}}

/* ============================================================
   炫酷特效（fx.js 配套样式）
   ============================================================ */
/* 全页粒子背景画布（screen 叠加发光，暗色背景下更通透） */
#fx-particles{position:fixed;inset:0;z-index:-1;pointer-events:none;mix-blend-mode:screen}

/* （自定义光标已移除，恢复系统光标） */

/* 标题辉光 */
.hero-title,.ph-title{filter:drop-shadow(0 0 26px rgba(34,211,238,.35)) drop-shadow(0 0 60px rgba(139,92,246,.2))}
.sec-title span{filter:drop-shadow(0 0 18px rgba(34,211,238,.3))}

/* 扫描线 CRT 效果 + 暗角（增加画面纵深） */
body::after{content:'';position:fixed;inset:0;z-index:9998;pointer-events:none;opacity:.5;background:radial-gradient(ellipse at 50% 42%,transparent 55%,rgba(2,4,10,.5) 100%),repeating-linear-gradient(0deg,rgba(255,255,255,.012) 0 1px,transparent 1px 3px)}
/* 顶部光带 */
body::before{content:'';position:fixed;top:0;left:0;right:0;height:2px;z-index:9997;pointer-events:none;background:linear-gradient(90deg,transparent,#22d3ee,#8b5cf6,#ec4899,transparent);background-size:200% 100%;animation:topGlow 6s linear infinite}
@keyframes topGlow{0%{background-position:200% 0}100%{background-position:-200% 0}}

/* 渐变流动边框（module-card hover 时） */
.module-card::after{content:'';position:absolute;inset:-1px;border-radius:24px;padding:1.5px;background:linear-gradient(120deg,#22d3ee,#3b82f6,#8b5cf6,#ec4899,#22d3ee);background-size:300% 100%;-webkit-mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);-webkit-mask-composite:xor;mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);mask-composite:exclude;opacity:0;transition:opacity .4s;animation:borderFlow 3s linear infinite;pointer-events:none}
.module-card:hover::after{opacity:1}
@keyframes borderFlow{to{background-position:300% 0}}

/* 全息状态面板（已移除，改用粒子流） */

/* ============================================================
   响应式
   ============================================================ */
@media(max-width:960px){
  .nav-links{position:fixed;top:0;right:-100%;width:70%;max-width:320px;height:100vh;background:rgba(7,11,22,.97);flex-direction:column;padding:90px 34px;gap:22px;transition:.4s}
  .nav-links.open{right:0}
  .burger{display:block}
  .module-grid{grid-template-columns:1fr;max-width:480px;margin:0 auto}
  .dir-grid{grid-template-columns:1fr;max-width:480px;margin:0 auto}
  .klist{grid-template-columns:1fr}
  .stats-bar{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:560px){
  section{padding:80px 0}
  .sec-block{padding:28px 22px}
  .sec-block-head{flex-direction:column;text-align:center;gap:12px}
  .tut{padding:26px 20px}
  .chal-link{margin-left:0}
  .stats-bar{grid-template-columns:1fr}
}