/* ============================================
   锐影学堂 · 前台设计系统
   ============================================ */
:root{
  --brand:#5b4bdb;
  --brand-2:#8b5cf6;
  --brand-3:#06b6d4;
  --brand-dark:#3f2fb3;
  --ink:#141726;
  --ink-2:#3c4257;
  --ink-3:#6b7391;
  --ink-4:#9aa1b8;
  --line:#e9ebf3;
  --line-2:#f2f3f8;
  --bg:#f7f8fc;
  --card:#ffffff;
  --ok:#10b981;
  --warn:#f59e0b;
  --danger:#ef4444;
  --shadow-sm:0 1px 2px rgba(20,23,38,.04),0 2px 8px rgba(20,23,38,.04);
  --shadow:0 4px 12px rgba(20,23,38,.06),0 12px 32px rgba(20,23,38,.06);
  --shadow-lg:0 12px 28px rgba(20,23,38,.10),0 32px 64px rgba(20,23,38,.10);
  --radius:14px;
  --radius-lg:20px;
  --radius-sm:9px;
  --max:1280px;
  --header-h:66px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{
  font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Helvetica,Arial,sans-serif;
  background:var(--bg);color:var(--ink);line-height:1.7;font-size:15px;
  -webkit-font-smoothing:antialiased;overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
button,input,select,textarea{font-family:inherit;font-size:inherit;color:inherit}
ul,ol{list-style:none}
button{cursor:pointer;border:none;background:none}
table{border-collapse:collapse;width:100%}

.wrap{max-width:var(--max);margin:0 auto;padding:0 20px}

/* ---------- 顶部导航 ---------- */
.header{
  position:sticky;top:0;z-index:100;height:var(--header-h);
  background:rgba(255,255,255,.86);backdrop-filter:saturate(180%) blur(18px);
  border-bottom:1px solid var(--line);
}
.header .wrap{height:100%;display:flex;align-items:center;gap:28px}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:19px;letter-spacing:-.4px;flex-shrink:0}
.logo-mark{
  width:34px;height:34px;border-radius:10px;flex-shrink:0;
  background:linear-gradient(135deg,var(--brand-2),var(--brand-3));
  display:grid;place-items:center;color:#fff;font-size:17px;
  box-shadow:0 4px 12px rgba(91,75,219,.35);
}
.nav{display:flex;align-items:center;gap:4px;flex:1}
.nav a{
  padding:8px 14px;border-radius:9px;font-size:14.5px;color:var(--ink-2);
  font-weight:500;transition:.18s;white-space:nowrap;
}
.nav a:hover{background:var(--line-2);color:var(--brand)}
.nav a.on{color:var(--brand);background:rgba(91,75,219,.08);font-weight:600}
.header-right{display:flex;align-items:center;gap:10px;flex-shrink:0}
.search-box{position:relative}
.search-box input{
  width:190px;height:38px;border-radius:10px;border:1px solid var(--line);
  background:var(--bg);padding:0 14px 0 36px;font-size:13.5px;transition:.2s;outline:none;
}
.search-box input:focus{border-color:var(--brand);background:#fff;box-shadow:0 0 0 3px rgba(91,75,219,.1);width:230px}
.search-box svg{position:absolute;left:12px;top:50%;transform:translateY(-50%);width:15px;height:15px;color:var(--ink-4)}
.avatar-btn{
  width:38px;height:38px;border-radius:11px;overflow:hidden;flex-shrink:0;
  background:linear-gradient(135deg,var(--brand-2),var(--brand-3));
  display:grid;place-items:center;color:#fff;font-weight:700;font-size:14px;
}
.avatar-btn img{width:100%;height:100%;object-fit:cover}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:7px;
  height:40px;padding:0 20px;border-radius:10px;font-size:14.5px;font-weight:600;
  transition:.18s;white-space:nowrap;border:1px solid transparent;
}
.btn-primary{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;box-shadow:0 3px 10px rgba(91,75,219,.28)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 6px 18px rgba(91,75,219,.38)}
.btn-ghost{background:#fff;border-color:var(--line);color:var(--ink-2)}
.btn-ghost:hover{border-color:var(--brand);color:var(--brand)}
.btn-soft{background:rgba(91,75,219,.09);color:var(--brand)}
.btn-soft:hover{background:rgba(91,75,219,.16)}
.btn-lg{height:48px;padding:0 30px;font-size:15.5px;border-radius:12px}
.btn-sm{height:32px;padding:0 13px;font-size:13px;border-radius:8px}
.btn-block{width:100%}
.btn:disabled{opacity:.55;cursor:not-allowed;transform:none!important}

.menu-toggle{display:none;width:40px;height:40px;border-radius:10px;align-items:center;justify-content:center}
.menu-toggle svg{width:21px;height:21px}

/* ---------- 移动端抽屉 ---------- */
.mobile-menu{position:fixed;inset:0;z-index:200;display:none}
.mobile-menu.on{display:block}
.mobile-menu .mask{position:absolute;inset:0;background:rgba(16,18,32,.5);backdrop-filter:blur(3px)}
.mobile-menu .panel{
  position:absolute;top:0;right:0;bottom:0;width:82%;max-width:320px;background:#fff;
  padding:22px;overflow-y:auto;box-shadow:var(--shadow-lg);animation:slideIn .24s ease;
}
@keyframes slideIn{from{transform:translateX(100%)}to{transform:translateX(0)}}
.mobile-menu h3{font-size:12px;color:var(--ink-4);text-transform:uppercase;letter-spacing:1px;margin:20px 0 8px}
.mobile-menu a.m-link{display:block;padding:11px 12px;border-radius:10px;font-size:15px;color:var(--ink-2)}
.mobile-menu a.m-link:hover{background:var(--line-2);color:var(--brand)}

/* ---------- Hero ---------- */
.hero{position:relative;overflow:hidden;background:linear-gradient(160deg,#171a35 0%,#2b2168 48%,#3d2a7d 100%);color:#fff;padding:64px 0 76px}
.hero::before{
  content:"";position:absolute;width:600px;height:600px;border-radius:50%;
  background:radial-gradient(circle,rgba(139,92,246,.45),transparent 68%);
  top:-260px;right:-140px;filter:blur(30px);
}
.hero::after{
  content:"";position:absolute;width:480px;height:480px;border-radius:50%;
  background:radial-gradient(circle,rgba(6,182,212,.32),transparent 68%);
  bottom:-230px;left:-120px;filter:blur(30px);
}
.hero .wrap{position:relative;z-index:2;display:grid;grid-template-columns:1.15fr .85fr;gap:52px;align-items:center}
.hero-tag{
  display:inline-flex;align-items:center;gap:7px;padding:6px 14px;border-radius:100px;
  background:rgba(255,255,255,.13);border:1px solid rgba(255,255,255,.2);
  font-size:13px;margin-bottom:20px;backdrop-filter:blur(8px);
}
.hero h1{font-size:44px;line-height:1.22;font-weight:800;letter-spacing:-1.2px;margin-bottom:18px}
.hero h1 em{
  font-style:normal;background:linear-gradient(120deg,#a78bfa,#22d3ee);
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.hero p{font-size:16.5px;color:rgba(255,255,255,.76);margin-bottom:30px;max-width:560px}
.hero-stats{display:flex;gap:36px;margin-top:36px}
.hero-stats b{display:block;font-size:28px;font-weight:800;letter-spacing:-1px}
.hero-stats span{font-size:13.5px;color:rgba(255,255,255,.62)}
.hero-actions{display:flex;gap:13px;flex-wrap:wrap}
.hero .btn-ghost{background:rgba(255,255,255,.12);border-color:rgba(255,255,255,.24);color:#fff}
.hero .btn-ghost:hover{background:rgba(255,255,255,.2);color:#fff;border-color:rgba(255,255,255,.4)}
.hero-visual{
  border-radius:var(--radius-lg);padding:22px;
  background:rgba(255,255,255,.09);border:1px solid rgba(255,255,255,.16);
  backdrop-filter:blur(16px);box-shadow:0 24px 60px rgba(0,0,0,.28);
}
.hero-visual .hv-head{display:flex;align-items:center;gap:7px;margin-bottom:16px}
.hero-visual .hv-head i{width:10px;height:10px;border-radius:50%;background:rgba(255,255,255,.28)}
.hv-item{display:flex;gap:12px;align-items:center;padding:11px 13px;border-radius:12px;background:rgba(255,255,255,.08);margin-bottom:9px;transition:.2s}
.hv-item:hover{background:rgba(255,255,255,.15);transform:translateX(4px)}
.hv-ico{width:36px;height:36px;border-radius:10px;display:grid;place-items:center;font-size:17px;flex-shrink:0;background:rgba(255,255,255,.14)}
.hv-item b{font-size:14px;display:block}
.hv-item span{font-size:12.5px;color:rgba(255,255,255,.6)}

/* ---------- 广告位 ---------- */
.ad-slot{margin:26px 0}
.ad-banner{border-radius:var(--radius-lg);overflow:hidden;position:relative;background:var(--card);box-shadow:var(--shadow-sm);border:1px solid var(--line)}
.ad-banner img{width:100%;display:block;max-height:420px;object-fit:cover}
.ad-banner .ad-tag{
  position:absolute;right:14px;bottom:12px;background:rgba(20,23,38,.55);color:#fff;
  font-size:11px;padding:3px 9px;border-radius:6px;backdrop-filter:blur(6px);
}
.ad-text{
  padding:20px 24px;background:linear-gradient(120deg,var(--brand),var(--brand-2));
  color:#fff;border-radius:var(--radius-lg);
}
.ad-text h4{font-size:17px;margin-bottom:6px}
.ad-text p{font-size:13.5px;opacity:.9}
.ad-slide{position:relative;border-radius:var(--radius-lg);overflow:hidden;box-shadow:var(--shadow)}
.ad-slide img{width:100%;max-height:440px;object-fit:cover;display:none}
.ad-slide img.on{display:block;animation:fadeIn .5s ease}
@keyframes fadeIn{from{opacity:0}to{opacity:1}}
.slide-dots{position:absolute;bottom:16px;left:50%;transform:translateX(-50%);display:flex;gap:7px}
.slide-dots i{width:8px;height:8px;border-radius:50%;background:rgba(255,255,255,.5);cursor:pointer;transition:.2s}
.slide-dots i.on{background:#fff;width:22px;border-radius:5px}

/* ---------- 区块标题 ---------- */
.section{margin:56px 0}
.sec-head{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:26px}
.sec-head h2{font-size:27px;font-weight:800;letter-spacing:-.7px;display:flex;align-items:center;gap:11px}
.sec-head h2::before{content:"";width:5px;height:26px;border-radius:3px;background:linear-gradient(180deg,var(--brand-2),var(--brand-3))}
.sec-head p{color:var(--ink-3);font-size:14.5px;margin-top:4px}
.sec-head .more{color:var(--brand);font-size:14px;font-weight:600;white-space:nowrap}

/* ---------- 分类 ---------- */
.cat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:16px}
.cat-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px;transition:.22s;position:relative;overflow:hidden;
}
.cat-card::after{
  content:"";position:absolute;right:-30px;top:-30px;width:110px;height:110px;border-radius:50%;
  background:linear-gradient(135deg,rgba(91,75,219,.08),rgba(6,182,212,.06));transition:.3s;
}
.cat-card:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:rgba(91,75,219,.3)}
.cat-card:hover::after{transform:scale(1.5)}
.cat-ico{font-size:28px;margin-bottom:12px;position:relative;z-index:1}
.cat-card h4{font-size:16.5px;margin-bottom:5px;position:relative;z-index:1}
.cat-card p{font-size:13px;color:var(--ink-3);position:relative;z-index:1;line-height:1.65}

/* ---------- 课程卡片 ---------- */
.course-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:22px}
.course-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  overflow:hidden;transition:.24s;display:flex;flex-direction:column;
}
.course-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);border-color:rgba(91,75,219,.28)}
.cc-cover{position:relative;aspect-ratio:16/9;overflow:hidden;background:linear-gradient(135deg,#dcd9f7,#e8f4f8)}
.cc-cover img{width:100%;height:100%;object-fit:cover;transition:.5s}
.course-card:hover .cc-cover img{transform:scale(1.06)}
.cc-cover .cc-cat{
  position:absolute;top:12px;left:12px;padding:4px 11px;border-radius:7px;
  background:rgba(255,255,255,.92);font-size:12px;font-weight:600;color:var(--brand);
  backdrop-filter:blur(8px);
}
.cc-badge{
  position:absolute;top:12px;right:12px;padding:4px 10px;border-radius:7px;
  font-size:11.5px;font-weight:700;backdrop-filter:blur(8px);
}
.badge-trial{background:rgba(16,185,129,.94);color:#fff}
.badge-new{background:rgba(239,68,68,.94);color:#fff}
.badge-hot{background:rgba(245,158,11,.94);color:#fff}
.cc-play{
  position:absolute;inset:0;display:grid;place-items:center;opacity:0;transition:.24s;
  background:rgba(20,23,38,.28);backdrop-filter:blur(2px);
}
.course-card:hover .cc-play{opacity:1}
.cc-play i{
  width:48px;height:48px;border-radius:50%;background:rgba(255,255,255,.95);
  display:grid;place-items:center;color:var(--brand);box-shadow:0 6px 20px rgba(0,0,0,.24);
}
.cc-body{padding:17px 18px 18px;flex:1;display:flex;flex-direction:column}
.cc-body h3{font-size:16.5px;font-weight:700;line-height:1.45;margin-bottom:7px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.cc-sub{font-size:13px;color:var(--ink-3);margin-bottom:13px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;line-height:1.6;min-height:41px}
.cc-meta{display:flex;gap:13px;font-size:12.5px;color:var(--ink-4);margin-bottom:14px;flex-wrap:wrap}
.cc-meta span{display:flex;align-items:center;gap:4px}
.cc-foot{margin-top:auto;display:flex;align-items:center;justify-content:space-between;gap:10px;padding-top:13px;border-top:1px solid var(--line-2)}
.cc-price{display:flex;align-items:baseline;gap:7px}
.cc-price b{font-size:21px;font-weight:800;color:var(--danger);letter-spacing:-.6px}
.cc-price s{font-size:13px;color:var(--ink-4)}
.cc-price .free{color:var(--ok)}

/* ---------- 特色 ---------- */
.feature-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:16px}
.feature{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;transition:.2s}
.feature:hover{box-shadow:var(--shadow);transform:translateY(-3px)}
.feature .fi{width:44px;height:44px;border-radius:13px;display:grid;place-items:center;font-size:21px;margin-bottom:14px}
.feature h4{font-size:15.5px;margin-bottom:7px}
.feature p{font-size:13.5px;color:var(--ink-3);line-height:1.75}

/* ---------- 页脚 ---------- */
.footer{background:#141726;color:#9aa1b8;padding:50px 0 26px;margin-top:70px}
.footer-grid{display:grid;grid-template-columns:1.6fr repeat(3,1fr);gap:40px;margin-bottom:36px}
.footer h5{color:#fff;font-size:14.5px;margin-bottom:15px;font-weight:700}
.footer a{display:block;color:#9aa1b8;font-size:13.5px;padding:5px 0;transition:.16s}
.footer a:hover{color:#fff}
.footer-logo{display:flex;align-items:center;gap:10px;color:#fff;font-size:18px;font-weight:800;margin-bottom:13px}
.footer p{font-size:13.5px;line-height:1.9;max-width:320px}
.footer-bot{border-top:1px solid rgba(255,255,255,.09);padding-top:20px;text-align:center;font-size:13px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px}

/* ---------- 通用面板 ---------- */
.panel{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow-sm)}
.breadcrumb{font-size:13.5px;color:var(--ink-3);padding:18px 0;display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.breadcrumb a:hover{color:var(--brand)}
.breadcrumb i{font-style:normal;color:var(--ink-4)}

.tag{display:inline-block;padding:3px 10px;border-radius:6px;font-size:12px;background:var(--line-2);color:var(--ink-3);font-weight:500}
.tag-brand{background:rgba(91,75,219,.1);color:var(--brand)}
.tag-ok{background:rgba(16,185,129,.12);color:var(--ok)}
.tag-warn{background:rgba(245,158,11,.14);color:#b45309}

.empty{text-align:center;padding:70px 20px;color:var(--ink-4)}
.empty .ei{font-size:52px;margin-bottom:14px;opacity:.55}
.empty h3{font-size:17px;color:var(--ink-2);margin-bottom:8px}
.empty p{font-size:14px;margin-bottom:20px}

/* ---------- 分页 ---------- */
.pagination{display:flex;gap:7px;justify-content:center;align-items:center;margin:40px 0 10px;flex-wrap:wrap}
.pg{
  min-width:38px;height:38px;padding:0 12px;border-radius:10px;display:inline-flex;
  align-items:center;justify-content:center;background:#fff;border:1px solid var(--line);
  font-size:14px;color:var(--ink-2);transition:.16s;
}
.pg:hover{border-color:var(--brand);color:var(--brand)}
.pg.active{background:var(--brand);border-color:var(--brand);color:#fff;font-weight:600}
.pg-dot{color:var(--ink-4);padding:0 4px}

/* ---------- 响应式 ---------- */
@media(max-width:1000px){
  .hero .wrap{grid-template-columns:1fr;gap:34px}
  .hero h1{font-size:36px}
  .hero-visual{max-width:520px}
  .footer-grid{grid-template-columns:1fr 1fr;gap:30px}
}
@media(max-width:820px){
  .nav,.search-box{display:none}
  .menu-toggle{display:flex}
  .header .wrap{gap:12px}
  .hero{padding:42px 0 52px}
  .hero h1{font-size:30px;letter-spacing:-.8px}
  .hero p{font-size:15px}
  .hero-stats{gap:24px}
  .hero-stats b{font-size:22px}
  .section{margin:38px 0}
  .sec-head h2{font-size:22px}
  .course-grid{grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:15px}
  .cc-body h3{font-size:15px}
  .footer-grid{grid-template-columns:1fr}
  .footer-bot{flex-direction:column;text-align:center}
}
@media(max-width:520px){
  .wrap{padding:0 15px}
  .hero h1{font-size:25px}
  .hero-stats{flex-wrap:wrap;gap:18px}
  .course-grid{grid-template-columns:1fr;gap:14px}
  .sec-head{align-items:flex-start;flex-direction:column;gap:9px}
  .panel{padding:18px}
  .cat-grid{grid-template-columns:1fr}
}