/* ============ AI办公实战课 · 科技/宇宙视觉系统 v2 ============ */
:root{
  --bg:#060914; --bg2:#0a1024; --panel:rgba(255,255,255,.045); --panel2:rgba(255,255,255,.07);
  --cyan:#22D3EE; --purple:#8B5CF6; --pink:#F472B6; --blue:#3B82F6;
  --ink:#e8eeff; --ink2:#9fb0d9; --ink3:#6b7aa6;
  --line:rgba(120,160,255,.18); --line2:rgba(120,160,255,.32);
  --glow-c:rgba(34,211,238,.5); --glow-p:rgba(139,92,246,.5);
  --r:16px; --maxw:1140px;
  --font:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei","Source Han Sans SC",sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--font);background:var(--bg);color:var(--ink);line-height:1.75;-webkit-font-smoothing:antialiased;overflow-x:hidden;position:relative;min-height:100vh}
/* 背景：粒子canvas + 星云光晕 */
#bg{position:fixed;inset:0;width:100%;height:100%;z-index:-2;display:block}
body::before{content:"";position:fixed;inset:0;z-index:-1;pointer-events:none;
  background:
    radial-gradient(60vw 60vh at 15% -5%, rgba(139,92,246,.22), transparent 60%),
    radial-gradient(55vw 55vh at 95% 10%, rgba(34,211,238,.18), transparent 60%),
    radial-gradient(70vw 50vh at 50% 110%, rgba(59,130,246,.16), transparent 60%);
}
a{color:var(--cyan);text-decoration:none;transition:.2s}
a:hover{color:#7df1ff}
img{max-width:100%}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 22px}
h1,h2,h3{line-height:1.25;letter-spacing:.5px;font-weight:800}
.grad{background:linear-gradient(100deg,var(--cyan),var(--purple) 60%,var(--pink));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;color:transparent}

/* 按钮 */
.btn{display:inline-block;border:0;cursor:pointer;font-size:16px;font-weight:700;color:#04121a;
  padding:14px 34px;border-radius:999px;letter-spacing:1px;
  background:linear-gradient(100deg,var(--cyan),var(--purple));
  box-shadow:0 0 0 1px rgba(255,255,255,.12) inset,0 8px 30px rgba(34,211,238,.32);
  transition:.22s;position:relative}
.btn:hover{transform:translateY(-2px);box-shadow:0 0 0 1px rgba(255,255,255,.2) inset,0 12px 40px rgba(139,92,246,.5);color:#04121a}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--line2);box-shadow:none;backdrop-filter:blur(6px)}
.btn.ghost:hover{border-color:var(--cyan);color:#7df1ff;box-shadow:0 0 24px rgba(34,211,238,.25)}

/* 顶栏 */
.site-hd{position:sticky;top:0;z-index:30;background:rgba(6,9,20,.72);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.site-hd .nav{display:flex;align-items:center;justify-content:space-between;height:60px;gap:14px}
.brand{font-size:19px;font-weight:900;letter-spacing:1px;color:#fff;white-space:nowrap}
.brand::before{content:"◈ ";color:var(--cyan)}
.menu{display:flex;gap:2px;overflow-x:auto;scrollbar-width:none}
.menu::-webkit-scrollbar{display:none}
.menu a{color:var(--ink2);padding:7px 12px;border-radius:8px;font-size:14px;white-space:nowrap}
.menu a.on,.menu a:hover{background:rgba(120,160,255,.12);color:#fff;box-shadow:0 0 18px rgba(34,211,238,.18) inset}

/* hero */
.hero-home,.hero-prod{text-align:center;padding:96px 0 70px;position:relative}
.hero-home h1{font-size:clamp(30px,5.2vw,56px);margin-bottom:18px;text-shadow:0 0 38px rgba(34,211,238,.25)}
.hero-prod h1{font-size:clamp(26px,4.4vw,44px);margin:16px 0}
.lead{color:var(--ink2);font-size:clamp(15px,1.8vw,19px);max-width:720px;margin:0 auto 26px}
.hero-cta{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.hero-prod .price-tag{margin:20px 0;font-size:15px;color:var(--ink2)}
.price-tag b{font-size:26px;color:#fff;text-shadow:0 0 20px var(--glow-c);margin-right:6px}
.price-tag s{opacity:.5;margin-left:4px}

/* 课程卡网格 */
.grid-courses{display:grid;grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:20px;margin-top:26px}
.course-card{position:relative;background:var(--panel);border:1px solid var(--line);border-radius:var(--r);
  padding:24px;display:flex;flex-direction:column;color:var(--ink);overflow:hidden;
  backdrop-filter:blur(8px);transition:.25s;animation:fadeUp .6s both}
.course-card::after{content:"";position:absolute;inset:0;border-radius:var(--r);padding:1px;pointer-events:none;
  background:linear-gradient(120deg,transparent,rgba(34,211,238,.4),transparent);
  -webkit-mask:linear-gradient(#000 0 0) content-box,linear-gradient(#000 0 0);-webkit-mask-composite:xor;mask-composite:exclude;opacity:0;transition:.25s}
.course-card:hover{transform:translateY(-6px);border-color:var(--line2);box-shadow:0 18px 50px rgba(10,16,40,.7),0 0 40px rgba(139,92,246,.18)}
.course-card:hover::after{opacity:1}
.cc-badge{align-self:flex-start;font-size:12px;font-weight:700;letter-spacing:.5px;padding:4px 12px;border-radius:999px;
  background:rgba(34,211,238,.12);color:var(--cyan);border:1px solid rgba(34,211,238,.3)}
.course-card h3{font-size:21px;margin:14px 0 7px;color:#fff}
.course-card p{color:var(--ink2);font-size:14px;flex:1}
.cc-foot{display:flex;justify-content:space-between;align-items:center;margin-top:18px}
.price{color:#fff;font-weight:800;font-size:19px;text-shadow:0 0 16px var(--glow-c)}
.price s{color:var(--ink3);font-size:13px;font-weight:400;margin-left:5px;text-shadow:none}
.more{color:var(--cyan);font-size:13px}
.type-free .cc-badge{background:rgba(52,211,153,.12);color:#34d399;border-color:rgba(52,211,153,.3)}
.type-b2b .cc-badge{background:rgba(244,114,182,.12);color:var(--pink);border-color:rgba(244,114,182,.3)}
.type-camp .cc-badge{background:rgba(251,191,36,.12);color:#fbbf24;border-color:rgba(251,191,36,.3)}

/* 区块 */
section{padding:46px 0}
.sec-title{font-size:clamp(23px,3vw,32px);text-align:center;margin:10px 0 8px;color:#fff}
.sec-sub{text-align:center;color:var(--ink2);margin-bottom:28px}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:20px 22px;backdrop-filter:blur(8px)}
.card p{color:var(--ink2)}
.card.pain{border-left:3px solid var(--pink)}
.gain{display:flex;gap:12px;align-items:flex-start;background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:15px 18px;backdrop-filter:blur(8px);transition:.2s}
.gain:hover{border-color:var(--line2);box-shadow:0 0 26px rgba(34,211,238,.12)}
.gain .ck{color:var(--cyan);font-weight:900;font-size:18px;text-shadow:0 0 12px var(--glow-c)}
.gain p{font-size:15px}
table.syl{width:100%;border-collapse:collapse;background:var(--panel);border:1px solid var(--line);border-radius:14px;overflow:hidden;font-size:15px;backdrop-filter:blur(8px)}
.syl th{background:rgba(139,92,246,.18);color:#fff;padding:13px 16px;text-align:left;font-weight:700;letter-spacing:.5px}
.syl td{padding:12px 16px;border-top:1px solid var(--line);color:var(--ink2)}
.syl tr:hover td{background:rgba(120,160,255,.05)}
.hl-box{background:linear-gradient(120deg,rgba(34,211,238,.1),rgba(139,92,246,.1));border:1px solid var(--line2);border-radius:14px;padding:24px 26px;box-shadow:0 0 40px rgba(139,92,246,.12) inset}
.hl-box h3{color:#fff;font-size:20px;margin-bottom:8px}
.hl-box p{color:var(--ink2);font-size:16px}
.fit{display:grid;gap:10px}.fit div{font-size:16px;color:var(--ink2);padding:10px 16px;background:var(--panel);border:1px solid var(--line);border-radius:10px}
.band{margin:46px auto;border-radius:18px;padding:1px;background:linear-gradient(120deg,rgba(34,211,238,.4),rgba(139,92,246,.4))}
.band-inner{background:#080d1e;border-radius:17px;padding:34px;text-align:center}
.band-inner h2{font-size:25px;margin-bottom:10px;color:#fff}
.band-inner p{color:var(--ink2)}
.faq .card{margin-bottom:12px}.faq h3{font-size:16px;color:var(--cyan);margin-bottom:5px}

/* 表单 */
.enroll{max-width:540px;background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:26px;backdrop-filter:blur(10px);box-shadow:0 0 50px rgba(10,16,40,.5)}
.frow{margin-bottom:13px}
.enroll input,.enroll textarea{width:100%;padding:13px 15px;background:rgba(4,8,20,.6);border:1px solid var(--line2);border-radius:10px;color:var(--ink);font-size:15px;font-family:inherit;transition:.2s}
.enroll input:focus,.enroll textarea:focus{outline:none;border-color:var(--cyan);box-shadow:0 0 0 3px rgba(34,211,238,.15)}
.enroll input::placeholder,.enroll textarea::placeholder{color:var(--ink3)}
.enroll textarea{min-height:90px;resize:vertical}
.enroll .btn{width:100%;margin-top:6px}
.result{text-align:center;padding:90px 0}
.result h2{font-size:32px;margin-bottom:14px;color:#fff}
.result .btn{margin-top:20px}

/* 页脚 */
.site-ft{margin-top:60px;padding:34px 0;text-align:center;font-size:14px;color:var(--ink2);border-top:1px solid var(--line);background:rgba(6,9,20,.6)}
.site-ft a{color:var(--cyan)}.site-ft .muted{color:var(--ink3);font-size:13px;margin-top:8px}

@keyframes fadeUp{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:none}}
.course-card:nth-child(2){animation-delay:.05s}.course-card:nth-child(3){animation-delay:.1s}
.course-card:nth-child(4){animation-delay:.15s}.course-card:nth-child(5){animation-delay:.2s}
.course-card:nth-child(6){animation-delay:.25s}.course-card:nth-child(7){animation-delay:.3s}.course-card:nth-child(8){animation-delay:.35s}

@media(max-width:680px){
  .grid2{grid-template-columns:1fr}
  .hero-home,.hero-prod{padding:64px 0 48px}
  section{padding:34px 0}
  .menu{max-width:56vw;-webkit-mask-image:linear-gradient(90deg,#000 80%,transparent);mask-image:linear-gradient(90deg,#000 80%,transparent)}
}
/* ====== 大画面沉浸首页 ====== */
@property --a{syntax:'<angle>';inherits:false;initial-value:0deg}
.hero-cosmos{position:relative;min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:0 22px;overflow:hidden}
.hero-cosmos::after{content:"";position:absolute;left:50%;bottom:-2px;width:240%;height:44vh;transform:translateX(-50%) perspective(440px) rotateX(63deg);transform-origin:bottom;
  background-image:linear-gradient(rgba(34,211,238,.16) 1px,transparent 1px),linear-gradient(90deg,rgba(139,92,246,.16) 1px,transparent 1px);
  background-size:48px 48px;-webkit-mask:linear-gradient(transparent,#000 78%);mask:linear-gradient(transparent,#000 78%);opacity:.55;pointer-events:none}
.hero-inner{position:relative;z-index:2;animation:fadeUp .9s both}
.eyebrow{color:var(--cyan);letter-spacing:4px;font-size:13px;margin-bottom:22px;text-transform:uppercase}
.hero-title{font-size:clamp(40px,8.5vw,94px);line-height:1.04;font-weight:900;letter-spacing:1px;margin-bottom:22px;text-shadow:0 0 55px rgba(34,211,238,.3)}
.hero-sub{color:var(--ink2);font-size:clamp(15px,2vw,20px);max-width:720px;margin:0 auto 34px}
.scroll-ind{position:absolute;bottom:24px;left:50%;color:var(--ink3);font-size:12px;letter-spacing:2px;animation:bob 1.8s infinite;transform:translateX(-50%)}
@keyframes bob{0%,100%{transform:translateX(-50%) translateY(0)}50%{transform:translateX(-50%) translateY(9px)}}
.cosmos-courses{max-width:1180px;margin:0 auto;padding:46px 22px 20px}
.bigcards{display:grid;grid-template-columns:repeat(auto-fit,minmax(340px,1fr));gap:22px;margin-top:30px;perspective:1300px}
.bigcard{position:relative;min-height:248px;display:flex;flex-direction:column;justify-content:flex-end;padding:28px;border-radius:20px;overflow:hidden;color:var(--ink);
  background:linear-gradient(160deg,rgba(22,30,60,.72),rgba(9,14,32,.6));border:1px solid var(--line);backdrop-filter:blur(10px);
  transform-style:preserve-3d;transition:transform .14s ease-out,box-shadow .3s,border-color .3s;box-shadow:0 12px 40px rgba(4,8,20,.5);animation:fadeUp .6s both}
.bigcard::before{content:"";position:absolute;inset:0;border-radius:20px;padding:1.5px;pointer-events:none;z-index:1;
  background:conic-gradient(from var(--a),transparent 8%,var(--cyan),var(--purple),var(--pink),transparent 92%);
  -webkit-mask:linear-gradient(#000 0 0) content-box,linear-gradient(#000 0 0);-webkit-mask-composite:xor;mask-composite:exclude;opacity:0;transition:opacity .35s;animation:spin 6s linear infinite}
.bigcard:hover{border-color:transparent;box-shadow:0 26px 72px rgba(10,16,40,.72),0 0 64px rgba(139,92,246,.26)}
.bigcard:hover::before{opacity:1}
@keyframes spin{to{--a:360deg}}
.bc-num{position:absolute;top:2px;right:16px;font-size:122px;font-weight:900;font-style:italic;line-height:1;color:rgba(255,255,255,.045);z-index:0}
.bc-icon{font-size:42px;margin-bottom:auto;filter:drop-shadow(0 0 18px rgba(34,211,238,.55));position:relative;z-index:2}
.bigcard .cc-badge{position:relative;z-index:2;margin-top:14px}
.bigcard h3{font-size:24px;color:#fff;margin:12px 0 8px;position:relative;z-index:2}
.bigcard p{color:var(--ink2);font-size:14px;position:relative;z-index:2;flex:none;min-height:42px}
.bc-foot{display:flex;justify-content:space-between;align-items:center;margin-top:18px;position:relative;z-index:2}
.bc-foot .price{font-size:22px}
.enter{color:var(--cyan);font-weight:700;font-size:14px;letter-spacing:1px;transition:.25s}
.bigcard:hover .enter{text-shadow:0 0 18px var(--glow-c);transform:translateX(3px)}
@media(max-width:680px){.hero-cosmos{min-height:86vh}.bigcards{grid-template-columns:1fr}.bc-num{font-size:92px}}
/* ====== 一屏一课程 · 全屏节（左右两栏 + 强制吸附 + 进度光轨）====== */
body:has(.course-panel){scroll-snap-type:y mandatory;scroll-padding-top:56px}
.hero-cosmos.panel{scroll-snap-align:start}
@keyframes spinring{to{transform:rotate(360deg)}}
.course-panel{position:relative;min-height:100vh;display:flex;align-items:center;justify-content:center;scroll-snap-align:start;scroll-snap-stop:always;padding:84px 64px 84px 22px;overflow:hidden}
.course-panel::before{content:"";position:absolute;inset:0;z-index:0;pointer-events:none}
.course-panel.type-free::before{background:radial-gradient(56vw 58vh at 72% 50%,rgba(52,211,153,.15),transparent 62%)}
.course-panel.type-paid::before{background:radial-gradient(56vw 58vh at 72% 50%,rgba(34,211,238,.14),transparent 62%)}
.course-panel.type-camp::before{background:radial-gradient(56vw 58vh at 72% 50%,rgba(251,191,36,.14),transparent 62%)}
.course-panel.type-b2b::before{background:radial-gradient(56vw 58vh at 72% 50%,rgba(244,114,182,.14),transparent 62%)}
.cp-num{position:absolute;top:50%;right:2%;transform:translateY(-50%);font-size:min(40vw,460px);font-weight:900;font-style:italic;line-height:1;color:rgba(255,255,255,.03);z-index:0;pointer-events:none;-webkit-user-select:none;user-select:none}
.cp-inner{position:relative;z-index:2;width:100%;max-width:1040px;display:grid;grid-template-columns:1.05fr .95fr;gap:44px;align-items:center;opacity:0;transform:translateY(34px);transition:opacity .9s,transform .9s}
.course-panel.in .cp-inner{opacity:1;transform:none}
.cp-text{text-align:left}
.cp-visual{position:relative;display:flex;align-items:center;justify-content:center;min-height:300px}
.cp-visual::before{content:"";position:absolute;width:min(44vw,350px);height:min(44vw,350px);border-radius:50%;border:1px solid var(--line2);box-shadow:0 0 60px rgba(34,211,238,.16) inset,0 0 50px rgba(139,92,246,.14)}
.cp-visual::after{content:"";position:absolute;width:min(50vw,408px);height:min(50vw,408px);border-radius:50%;border:1px dashed rgba(120,160,255,.22);animation:spinring 26s linear infinite}
.cp-icon{font-size:clamp(108px,15vw,208px);filter:drop-shadow(0 0 34px rgba(34,211,238,.5));position:relative;z-index:2}
.cp-text .cc-badge{display:inline-block;margin-bottom:14px;font-size:14px;padding:5px 16px;border-radius:999px}
.cp-title{font-size:clamp(30px,5vw,58px);color:#fff;margin:8px 0 14px;text-shadow:0 0 44px rgba(34,211,238,.28);line-height:1.12}
.cp-sub{font-size:clamp(15px,1.7vw,21px);color:var(--ink2);margin:0 0 22px}
.cp-price{font-size:clamp(28px,4vw,50px);font-weight:900;margin-bottom:26px}
.cp-text .btn{font-size:17px;padding:15px 40px}
.dots{position:fixed;right:22px;top:50%;transform:translateY(-50%);z-index:25;display:flex;flex-direction:column;gap:16px}
.dots::before{content:"";position:absolute;left:50%;top:-5px;bottom:-5px;width:2px;transform:translateX(-50%);background:var(--line);z-index:0}
.dots-fill{position:absolute;left:50%;top:-5px;width:2px;transform:translateX(-50%);background:linear-gradient(var(--cyan),var(--purple));box-shadow:0 0 12px var(--glow-c);z-index:1;height:0;transition:height .4s ease}
.dots a{position:relative;z-index:2;display:block;width:11px;height:11px;border-radius:50%;border:1.5px solid var(--line2);background:var(--bg);transition:.25s}
.dots a:hover{border-color:var(--cyan)}
.dots a.on{background:var(--cyan);border-color:var(--cyan);box-shadow:0 0 14px var(--glow-c);transform:scale(1.35)}
@media(max-width:768px){
  body:has(.course-panel){scroll-snap-type:y proximity}
  .course-panel{padding:78px 20px;text-align:center}
  .cp-inner{grid-template-columns:1fr;gap:12px;max-width:560px}
  .cp-text{text-align:center}
  .cp-visual{order:-1;min-height:auto;margin-bottom:6px}
  .cp-visual::before{width:220px;height:220px}.cp-visual::after{width:256px;height:256px}
  .cp-icon{font-size:92px}
  .cp-num{font-size:72vw;right:auto;left:50%;transform:translate(-50%,-50%);top:40%}
  .dots{right:9px;gap:12px}.dots a{width:9px;height:9px}
}
@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}.cp-inner{opacity:1;transform:none}}