/* ==========================================================
   AI 课程落地页样式
   移动端优先 + PC 增强，适配抖音 App 内置浏览器 / 微信 / 主流浏览器
   ========================================================== */
*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;}
body{
  margin:0;padding:0 0 calc(74px + env(safe-area-inset-bottom));
  font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Helvetica Neue","Hiragino Sans GB","Microsoft YaHei",Arial,sans-serif;
  font-size:15px;line-height:1.7;color:#3A3F55;background:#F4F6FB;
  -webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent;
}
h1,h2,h3,h4,h5,p,ul,ol,figure{margin:0;padding:0;}
ul,ol{list-style:none;}
img,svg{display:block;max-width:100%;border:0;}
a{color:inherit;text-decoration:none;}
button,input,select,textarea{font-family:inherit;font-size:inherit;color:inherit;outline:none;}
button{border:0;background:none;cursor:pointer;-webkit-appearance:none;appearance:none;}
input,textarea{-webkit-appearance:none;appearance:none;border-radius:0;}
:root{
  --brand:#5B6CFF;--brand-2:#8B5CF6;
  --accent:#FF6A3D;--accent-2:#FF9F1C;
  --ink:#0F1222;--ink2:#3A3F55;--ink3:#737A93;--ink4:#A3A9BE;
  --line:#EAECF3;--bg:#F4F6FB;--card:#FFFFFF;
  --radius:14px;--radius-lg:20px;
  --shadow:0 6px 24px rgba(18,24,58,.07);
  --shadow-lg:0 14px 44px rgba(18,24,58,.14);
  --wrap:750px;
}
.wrap{width:100%;max-width:var(--wrap);margin:0 auto;}
.hide{display:none !important;}
.icon{width:1em;height:1em;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;flex:none;}

/* ============ 顶部导航 ============ */
.topbar{
  position:sticky;top:0;z-index:60;background:rgba(255,255,255,.94);
  -webkit-backdrop-filter:saturate(180%) blur(12px);backdrop-filter:saturate(180%) blur(12px);
  border-bottom:1px solid rgba(20,26,60,.06);
}
.topbar-in{display:flex;align-items:center;height:52px;padding:0 14px;}
.logo{display:flex;align-items:center;gap:8px;font-weight:800;color:var(--ink);font-size:16px;letter-spacing:.2px;}
.logo-mark{
  width:28px;height:28px;border-radius:8px;flex:none;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
  display:flex;align-items:center;justify-content:center;color:#fff;
  box-shadow:0 4px 12px rgba(91,108,255,.35);
}
.logo-mark .icon{width:17px;height:17px;stroke-width:2.2;}
.topnav{display:none;flex:1;align-items:center;justify-content:center;}
.topnav a{padding:6px 12px;border-radius:8px;font-size:14px;color:var(--ink2);transition:background .18s,color .18s;}
.topnav a:hover{background:#F0F2FA;color:var(--brand);}
.tb-spacer{flex:1;}
.btn-kefu{
  display:inline-flex;align-items:center;gap:5px;padding:6px 12px;border-radius:999px;
  font-size:13px;font-weight:600;color:var(--brand);background:#EEF0FF;border:1px solid #DDE1FF;
}
.btn-kefu .icon{width:14px;height:14px;}

/* ============ 锚点导航 ============ */
.subnav{background:#fff;border-bottom:1px solid var(--line);}
.subnav-in{display:flex;overflow-x:auto;padding:9px 14px;-webkit-overflow-scrolling:touch;scrollbar-width:none;}
.subnav-in::-webkit-scrollbar{display:none;}
.subnav a{
  flex:none;margin-right:6px;padding:6px 14px;border-radius:999px;background:#F3F5FB;
  font-size:13px;color:var(--ink2);white-space:nowrap;transition:.18s;
}
.subnav a.on{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;font-weight:600;}

/* ============ Hero ============ */
.hero{
  position:relative;overflow:hidden;color:#fff;
  background:linear-gradient(150deg,#141A36 0%,#221C4C 45%,#3A1E52 100%);
  padding:30px 0 40px;
}
.hero::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);
  background-size:42px 42px;
}
.hero::after{
  content:"";position:absolute;right:-90px;top:-70px;width:280px;height:280px;border-radius:50%;
  background:radial-gradient(circle,rgba(139,92,246,.5),transparent 68%);pointer-events:none;
}
.hero-in{position:relative;z-index:2;padding:0 20px;}
.hero-tag{
  display:inline-flex;align-items:center;gap:6px;padding:5px 12px;border-radius:999px;
  font-size:12px;font-weight:600;letter-spacing:.3px;
  background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.2);
  -webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);
}
.hero-tag .icon{width:13px;height:13px;color:#FFD08A;}
.hero h1{
  margin-top:16px;font-size:28px;line-height:1.35;font-weight:800;letter-spacing:-.3px;
  background:linear-gradient(100deg,#FFFFFF 20%,#C9D2FF 100%);
  -webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;
}
.hero-sub{margin-top:12px;font-size:14.5px;line-height:1.75;color:rgba(255,255,255,.76);}
.hero-chips{display:flex;flex-wrap:wrap;margin-top:18px;}
.chip{
  display:inline-flex;align-items:center;gap:5px;margin:0 8px 8px 0;padding:5px 11px;border-radius:8px;
  font-size:12.5px;background:rgba(255,255,255,.09);border:1px solid rgba(255,255,255,.14);
  color:rgba(255,255,255,.9);
}
.chip .icon{width:13px;height:13px;color:#8FE3C4;}
.hero-price{margin-top:20px;display:flex;align-items:flex-end;flex-wrap:wrap;}
.hero-price .cur{font-size:17px;font-weight:700;color:#FFC978;line-height:1;margin-bottom:5px;}
.hero-price .num{font-size:40px;font-weight:800;color:#FFC978;line-height:1;letter-spacing:-1px;font-variant-numeric:tabular-nums;}
.hero-price .tip{font-size:12.5px;color:rgba(255,255,255,.6);margin:0 0 5px 8px;}
.hero-btns{display:flex;margin-top:22px;}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:7px;
  height:48px;padding:0 22px;border-radius:12px;font-size:16px;font-weight:700;
  transition:transform .15s,box-shadow .2s,opacity .2s;
}
.btn:active{transform:scale(.975);}
.btn-block{width:100%;display:flex;}
.btn-primary{
  flex:1;color:#fff;background:linear-gradient(120deg,var(--accent),var(--accent-2));
  box-shadow:0 10px 26px rgba(255,106,61,.36);
}
.btn-primary .icon{width:17px;height:17px;}
.btn-ghost{
  flex:none;width:118px;margin-left:10px;color:#fff;background:rgba(255,255,255,.1);
  border:1px solid rgba(255,255,255,.24);font-weight:600;
}
.trust{display:flex;flex-wrap:wrap;margin-top:20px;padding-top:16px;border-top:1px solid rgba(255,255,255,.12);}
.trust div{display:flex;align-items:center;gap:6px;margin:0 18px 6px 0;font-size:12.5px;color:rgba(255,255,255,.72);}
.trust .icon{width:14px;height:14px;color:#8FE3C4;}

.hero-cards{position:relative;z-index:2;display:flex;margin-top:26px;padding:0 20px;}
.hcard{
  flex:1;margin-right:12px;padding:14px;border-radius:var(--radius);
  background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.14);
  -webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);
}
.hcard:last-child{margin-right:0;}
.hcard-ico{
  width:34px;height:34px;border-radius:10px;display:flex;align-items:center;justify-content:center;
  color:#fff;margin-bottom:10px;
}
.hcard-ico .icon{width:19px;height:19px;}
.ico-a{background:linear-gradient(135deg,#5B6CFF,#8B5CF6);}
.ico-b{background:linear-gradient(135deg,#FF6A3D,#FF9F1C);}
.hcard h4{font-size:14.5px;font-weight:700;color:#fff;line-height:1.45;}
.hcard p{margin-top:6px;font-size:12px;color:rgba(255,255,255,.65);line-height:1.6;}

/* ============ 通用区块 ============ */
.sec{padding:34px 0;background:var(--bg);}
.sec.white{background:#fff;}
.sec-in{padding:0 20px;}
.sec-head{text-align:center;margin-bottom:22px;}
.sec-kicker{
  display:inline-block;font-size:12px;font-weight:700;letter-spacing:1.5px;
  color:var(--brand);background:#EEF0FF;padding:4px 12px;border-radius:999px;margin-bottom:10px;
}
.sec-head h2{font-size:22px;line-height:1.4;font-weight:800;color:var(--ink);letter-spacing:-.2px;}
.sec-head p{margin-top:8px;font-size:13.5px;color:var(--ink3);}
.sec-head.left{text-align:left;}

/* 痛点 */
.pain-list{display:grid;grid-template-columns:1fr;}
.pain{display:flex;gap:11px;margin-bottom:10px;padding:15px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);}
.pain:last-child{margin-bottom:0;}
.pain-ico{
  width:26px;height:26px;border-radius:8px;flex:none;margin-top:1px;background:#FFF1EC;color:var(--accent);
  display:flex;align-items:center;justify-content:center;
}
.pain-ico .icon{width:15px;height:15px;}
.pain h4{font-size:15px;font-weight:700;color:var(--ink);}
.pain p{margin-top:4px;font-size:13px;color:var(--ink3);line-height:1.65;}

/* 能力 */
.gain-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px;}
.gain{padding:16px 14px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);}
.gain-n{
  font-size:12px;font-weight:800;letter-spacing:1px;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
  -webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;
}
.gain h4{margin-top:8px;font-size:14.5px;font-weight:700;color:var(--ink);line-height:1.5;}
.gain p{margin-top:6px;font-size:12.5px;color:var(--ink3);line-height:1.6;}

/* 课程大纲 */
.tabs{display:flex;margin-bottom:16px;}
.tab{
  flex:1;margin-right:8px;padding:11px 8px;border-radius:12px;background:#fff;box-shadow:var(--shadow);
  font-size:14px;font-weight:700;color:var(--ink2);text-align:center;border:2px solid transparent;
  transition:.2s;line-height:1.4;
}
.tab:last-child{margin-right:0;}
.tab.on{
  color:#fff;background:linear-gradient(135deg,var(--brand),var(--brand-2));
  box-shadow:0 8px 22px rgba(91,108,255,.3);
}
.tab small{display:block;font-size:11px;font-weight:500;opacity:.8;margin-top:2px;}
.syl{margin-bottom:12px;overflow:hidden;background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);}
.syl-h{display:flex;align-items:center;padding:14px 15px;}
.syl-no{
  width:26px;height:26px;border-radius:8px;flex:none;margin-right:10px;font-size:12.5px;font-weight:800;color:#fff;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
  display:flex;align-items:center;justify-content:center;
}
.syl-h h4{flex:1;font-size:15px;font-weight:700;color:var(--ink);}
.syl-h .cnt{font-size:12px;color:var(--ink4);flex:none;margin-right:8px;}
.syl-arrow{width:16px;height:16px;color:var(--ink4);transition:transform .25s;flex:none;}
.syl.open .syl-arrow{transform:rotate(180deg);}
.syl-b{max-height:0;transition:max-height .3s ease;overflow:hidden;}
.syl-b-in{padding:0 15px 14px 51px;}
.syl-b-in li{position:relative;font-size:13.5px;color:var(--ink2);line-height:1.9;padding-left:14px;}
.syl-b-in li::before{
  content:"";position:absolute;left:0;top:11px;width:5px;height:5px;border-radius:50%;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
}
.syl-meta{display:flex;flex-wrap:wrap;padding:12px 15px;margin:0 15px 14px 51px;background:#F6F7FC;border-radius:10px;}
.syl-meta span{font-size:12px;color:var(--ink3);display:inline-flex;align-items:center;gap:4px;margin-right:14px;}
.syl-meta .icon{width:13px;height:13px;color:var(--brand);}

/* 作品 */
.works{display:grid;grid-template-columns:1fr 1fr;gap:11px;}
.work{border-radius:var(--radius);overflow:hidden;background:#fff;box-shadow:var(--shadow);}
.work-thumb{position:relative;padding-top:56.25%;overflow:hidden;}
.work-thumb .fill{position:absolute;inset:0;}
.w1{background:linear-gradient(135deg,#5B6CFF,#8B5CF6);}
.w2{background:linear-gradient(135deg,#FF6A3D,#FF9F1C);}
.w3{background:linear-gradient(135deg,#0EA5A5,#22C1A6);}
.w4{background:linear-gradient(135deg,#E5457B,#8B5CF6);}
.w5{background:linear-gradient(135deg,#2B3A8F,#5B6CFF);}
.w6{background:linear-gradient(135deg,#F59E0B,#EF4444);}
.work-thumb .grid-lines{
  position:absolute;inset:0;opacity:.22;
  background-image:linear-gradient(rgba(255,255,255,.6) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(255,255,255,.6) 1px,transparent 1px);
  background-size:22px 22px;
}
.work-play{
  position:absolute;left:50%;top:50%;width:42px;height:42px;margin:-21px 0 0 -21px;border-radius:50%;
  background:rgba(255,255,255,.9);display:flex;align-items:center;justify-content:center;color:var(--ink);
  box-shadow:0 6px 18px rgba(0,0,0,.18);transition:transform .2s,background .2s;
}
.work.has-video{cursor:pointer;}
.work.has-video:hover .work-play{transform:scale(1.1);background:#fff;}
.work.has-video:active .work-play{transform:scale(.96);}
.work-soon{
  position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);
  padding:4px 13px;border-radius:999px;background:rgba(255,255,255,.92);
  color:var(--ink3);font-size:11.5px;font-weight:700;letter-spacing:.5px;
}
.work-thumb img.fill{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;}
.work-play .icon{width:18px;height:18px;fill:currentColor;stroke:none;margin-left:2px;}
.work-dur{position:absolute;right:8px;bottom:8px;padding:2px 7px;border-radius:5px;background:rgba(0,0,0,.55);color:#fff;font-size:11px;}
.work-tag{position:absolute;left:8px;top:8px;padding:2px 8px;border-radius:5px;background:rgba(255,255,255,.92);color:var(--ink);font-size:11px;font-weight:700;}
.work-info{padding:11px 12px;}
.work-info h4{font-size:13.5px;font-weight:700;color:var(--ink);line-height:1.5;}
.work-info p{margin-top:4px;font-size:11.5px;color:var(--ink4);}

/* 讲师 */
.teacher{display:flex;gap:14px;margin-bottom:11px;padding:16px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);}
.t-ava{
  width:56px;height:56px;border-radius:14px;flex:none;color:#fff;font-size:20px;font-weight:800;
  display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,var(--brand),var(--brand-2));
}
.t-ava.b{background:linear-gradient(135deg,var(--accent),var(--accent-2));}
.t-body h4{font-size:16px;font-weight:800;color:var(--ink);}
.t-body .role{margin-top:2px;font-size:12.5px;color:var(--brand);font-weight:600;}
.t-body p{margin-top:8px;font-size:13px;color:var(--ink3);line-height:1.7;}
.t-tags{display:flex;flex-wrap:wrap;margin-top:9px;}
.t-tags span{font-size:11.5px;padding:3px 9px;margin:0 6px 6px 0;border-radius:6px;background:#F2F4FA;color:var(--ink2);}

/* 人群 */
.people{display:grid;grid-template-columns:1fr;gap:12px;}
.pbox{padding:18px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);}
.pbox h4{display:flex;align-items:center;gap:7px;font-size:15.5px;font-weight:800;color:var(--ink);}
.pbox h4 .icon{width:18px;height:18px;}
.pbox.ok h4 .icon{color:#12B76A;}
.pbox.no h4 .icon{color:var(--ink4);}
.pbox ul{margin-top:11px;}
.pbox li{position:relative;padding-left:20px;font-size:13.5px;color:var(--ink2);line-height:2;}
.pbox li::before{content:"";position:absolute;left:5px;top:12px;width:6px;height:6px;border-radius:2px;}
.pbox.ok li::before{background:#12B76A;transform:rotate(45deg);}
.pbox.no li::before{background:var(--ink4);}

/* 保障 */
.guar{display:grid;grid-template-columns:1fr 1fr;gap:10px;}
.guar-item{padding:15px 13px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);text-align:center;}
.guar-ico{
  width:40px;height:40px;margin:0 auto 10px;border-radius:12px;background:linear-gradient(135deg,#EEF0FF,#F6EEFF);
  color:var(--brand);display:flex;align-items:center;justify-content:center;
}
.guar-ico .icon{width:21px;height:21px;}
.guar-item h4{font-size:14px;font-weight:700;color:var(--ink);}
.guar-item p{margin-top:5px;font-size:12px;color:var(--ink3);line-height:1.6;}

/* 评价 */
.revs{display:grid;grid-template-columns:1fr;gap:11px;}
.rev{padding:16px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);}
.rev-top{display:flex;align-items:center;gap:10px;}
.rev-ava{
  width:38px;height:38px;border-radius:50%;flex:none;color:#fff;font-size:14px;font-weight:700;
  display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#7C8CFF,#B07CFF);
}
.rev-ava.n2{background:linear-gradient(135deg,#FF8A5B,#FFB35B);}
.rev-ava.n3{background:linear-gradient(135deg,#22C1A6,#3ECFB0);}
.rev-ava.n4{background:linear-gradient(135deg,#5B6CFF,#22C1A6);}
.rev-name{font-size:14px;font-weight:700;color:var(--ink);}
.rev-meta{font-size:11.5px;color:var(--ink4);margin-top:1px;}
.rev p{margin-top:10px;font-size:13.5px;color:var(--ink2);line-height:1.75;}
.disclaimer{
  margin-top:14px;padding:11px 13px;border-radius:10px;background:#FFFAF0;border:1px solid #FFE9C7;
  font-size:12px;color:#96601C;line-height:1.7;
}
.disclaimer .icon{width:14px;height:14px;vertical-align:-2px;margin-right:5px;}

/* 价格 */
.plans{display:grid;grid-template-columns:1fr;gap:12px;}
.plan{position:relative;padding:20px 18px;border-radius:var(--radius-lg);background:#fff;box-shadow:var(--shadow);border:2px solid var(--line);transition:all .22s;cursor:pointer;}
.plan:hover{border-color:#D6DAE8;transform:translateY(-2px);box-shadow:var(--shadow-lg);}
.plan.rec{position:relative;}
.plan.sel{border-color:var(--brand);box-shadow:0 14px 40px rgba(91,108,255,.24);transform:translateY(-4px);background:linear-gradient(180deg,#FBFBFF 0%,#FFFFFF 30%);}
.plan.sel .plan-btn{color:#fff;background:linear-gradient(120deg,var(--accent),var(--accent-2));box-shadow:0 8px 22px rgba(255,106,61,.34);}
.plan.sel::before{content:"已选中";position:absolute;top:-11px;right:18px;padding:3px 11px;border-radius:999px;font-size:11.5px;font-weight:800;color:#fff;background:linear-gradient(135deg,var(--brand),var(--brand-2));box-shadow:0 4px 12px rgba(91,108,255,.32);z-index:2;}
.plan.rec.sel::before{display:none;}
.plan-badge{
  position:absolute;top:-11px;left:18px;padding:3px 11px;border-radius:999px;font-size:11.5px;font-weight:800;
  color:#fff;background:linear-gradient(120deg,var(--accent),var(--accent-2));box-shadow:0 4px 12px rgba(255,106,61,.35);
  z-index:3;
}
.plan h4{font-size:16.5px;font-weight:800;color:var(--ink);}
.plan-desc{margin-top:5px;font-size:12.5px;color:var(--ink3);min-height:34px;line-height:1.6;}
.plan-price{display:flex;align-items:flex-end;margin-top:12px;}
.plan-price .c{font-size:15px;font-weight:700;color:var(--accent);margin-bottom:4px;}
.plan-price .n{font-size:34px;font-weight:800;color:var(--accent);line-height:1;font-variant-numeric:tabular-nums;letter-spacing:-1px;}
.plan-price .u{font-size:12.5px;color:var(--ink4);margin:0 0 4px 4px;}
.plan-save{display:inline-block;margin-top:8px;padding:3px 9px;border-radius:6px;font-size:11.5px;font-weight:700;color:#0E9F6E;background:#E7F8F1;}
.plan ul{margin-top:14px;padding-top:13px;border-top:1px dashed var(--line);}
.plan li{display:flex;gap:8px;font-size:13.5px;color:var(--ink2);line-height:2;}
.plan li .icon{width:15px;height:15px;color:#12B76A;margin-top:8px;}
.plan-btn{display:block;width:100%;height:46px;margin-top:16px;border-radius:12px;font-size:15.5px;font-weight:700;color:var(--brand);background:#EEF0FF;transition:.2s;}
.plan.rec .plan-btn{color:#fff;background:linear-gradient(120deg,var(--accent),var(--accent-2));box-shadow:0 8px 22px rgba(255,106,61,.32);}
.plan-btn:active{transform:scale(.98);}

/* FAQ */
.faq{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden;}
.faq-i{border-bottom:1px solid var(--line);}
.faq-i:last-child{border-bottom:0;}
.faq-q{display:flex;align-items:center;gap:10px;width:100%;padding:15px;text-align:left;font-size:14.5px;font-weight:600;color:var(--ink);}
.faq-q .icon.q{width:17px;height:17px;color:var(--brand);flex:none;}
.faq-q .txt{flex:1;}
.faq-q .ar{width:16px;height:16px;color:var(--ink4);transition:transform .25s;}
.faq-i.open .ar{transform:rotate(180deg);}
.faq-a{max-height:0;overflow:hidden;transition:max-height .3s ease;}
.faq-a-in{padding:0 15px 15px 42px;font-size:13.5px;color:var(--ink2);line-height:1.8;}

/* 购买须知 */
.notice{padding:18px;border-radius:var(--radius);background:#fff;box-shadow:var(--shadow);border-left:4px solid var(--brand);}
.notice li{position:relative;padding-left:16px;font-size:13px;color:var(--ink2);line-height:1.9;}
.notice li::before{content:"";position:absolute;left:0;top:12px;width:5px;height:5px;border-radius:50%;background:var(--brand);}
.notice-links{
  margin-top:14px;padding-top:13px;border-top:1px dashed var(--line);
  font-size:12.5px;color:var(--ink3);line-height:1.9;
}
.notice-links a{color:var(--brand);font-weight:600;}

/* 页脚 */
.footer{background:#141A36;color:rgba(255,255,255,.6);padding:30px 0 calc(24px + env(safe-area-inset-bottom));font-size:12.5px;}
.footer-in{padding:0 20px;}
.footer h5{font-size:13.5px;color:#fff;font-weight:700;margin-bottom:12px;}
.footer p{line-height:1.9;}
.f-links{display:flex;flex-wrap:wrap;margin:16px 0;padding:16px 0;border-top:1px solid rgba(255,255,255,.1);border-bottom:1px solid rgba(255,255,255,.1);}
.f-links a{margin-right:16px;color:rgba(255,255,255,.75);line-height:2;}
.f-mail{color:rgba(255,255,255,.88);border-bottom:1px dashed rgba(255,255,255,.35);}
.f-contact{display:flex;flex-wrap:wrap;margin-top:12px;}
.f-contact span{display:inline-flex;align-items:center;gap:5px;margin:0 20px 6px 0;}
.f-contact .icon{width:14px;height:14px;}
.f-copy{margin-top:18px;padding-top:14px;border-top:1px solid rgba(255,255,255,.1);font-size:11.5px;color:rgba(255,255,255,.42);line-height:1.8;}

/* 吸底栏 */
.dock{
  position:fixed;left:0;right:0;bottom:0;z-index:80;background:rgba(255,255,255,.96);
  -webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);
  border-top:1px solid var(--line);padding:9px 14px calc(9px + env(safe-area-inset-bottom));
  box-shadow:0 -4px 20px rgba(18,24,58,.08);
}
.dock-in{display:flex;align-items:center;max-width:var(--wrap);margin:0 auto;}
.dock-info{flex:1;min-width:0;padding-right:12px;}
.dock-price{display:flex;align-items:flex-end;}
.dock-price .c{font-size:14px;font-weight:700;color:var(--accent);margin-bottom:3px;}
.dock-price .n{font-size:26px;font-weight:800;color:var(--accent);line-height:1;font-variant-numeric:tabular-nums;letter-spacing:-.5px;}
.dock-price .u{font-size:12px;color:var(--ink4);margin:0 0 3px 4px;}
.dock-sub{font-size:11.5px;color:var(--ink4);margin-top:3px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;}
.dock-btns{display:flex;flex:none;}
.dock-kefu{
  width:46px;height:46px;margin-right:8px;border-radius:12px;background:#F2F4FA;color:var(--ink2);
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:1px;font-size:10px;
}
.dock-kefu .icon{width:18px;height:18px;}
.dock-buy{
  height:46px;padding:0 26px;border-radius:12px;color:#fff;font-size:16px;font-weight:700;
  background:linear-gradient(120deg,var(--accent),var(--accent-2));
  box-shadow:0 8px 22px rgba(255,106,61,.34);display:flex;align-items:center;justify-content:center;
}
.dock-buy:active{transform:scale(.97);}

/* ============ 弹窗 ============ */
.mask{
  position:fixed;inset:0;z-index:100;background:rgba(10,14,32,.55);
  display:flex;align-items:flex-end;justify-content:center;opacity:0;visibility:hidden;transition:opacity .25s,visibility .25s;
}
.mask.show{opacity:1;visibility:visible;}
.sheet{
  width:100%;max-width:520px;max-height:92vh;overflow:hidden;background:#fff;border-radius:20px 20px 0 0;
  display:flex;flex-direction:column;transform:translateY(100%);
  transition:transform .3s cubic-bezier(.32,.72,0,1);padding-bottom:env(safe-area-inset-bottom);
}
.mask.show .sheet{transform:translateY(0);}
.sheet-h{display:flex;align-items:center;gap:10px;padding:16px 18px 12px;border-bottom:1px solid var(--line);flex:none;}
.sheet-h h3{flex:1;font-size:17px;font-weight:800;color:var(--ink);}
.sheet-close{width:30px;height:30px;border-radius:50%;background:#F2F4FA;color:var(--ink3);display:flex;align-items:center;justify-content:center;}
.sheet-close .icon{width:16px;height:16px;}
.sheet-b{flex:1;overflow-y:auto;-webkit-overflow-scrolling:touch;padding:16px 18px;}
.sheet-f{flex:none;padding:12px 18px;border-top:1px solid var(--line);background:#fff;}

.steps{display:flex;align-items:center;justify-content:center;margin-bottom:16px;}
.step{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--ink4);}
.step .dot{
  width:20px;height:20px;border-radius:50%;background:#EDEFF6;color:var(--ink4);font-size:11.5px;font-weight:700;
  display:flex;align-items:center;justify-content:center;
}
.step.on .dot{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;}
.step.on{color:var(--brand);font-weight:700;}
.step.done .dot{background:#12B76A;color:#fff;}
.step-line{width:22px;height:2px;margin:0 6px;background:#EDEFF6;}

.opt{display:flex;align-items:center;gap:11px;margin-bottom:10px;padding:14px;border:2px solid var(--line);border-radius:var(--radius);transition:.2s;cursor:pointer;}
.opt.on{border-color:var(--brand);background:#F7F8FF;}
.opt-radio{
  width:20px;height:20px;border-radius:50%;border:2px solid #D6DAE8;flex:none;
  display:flex;align-items:center;justify-content:center;transition:.2s;
}
.opt.on .opt-radio{border-color:var(--brand);background:var(--brand);}
.opt-radio .icon{width:12px;height:12px;color:#fff;stroke-width:3;opacity:0;}
.opt-radio.on .icon{opacity:1;}
.opt-body{flex:1;min-width:0;}
.opt-body h4{font-size:15px;font-weight:700;color:var(--ink);}
.opt-body p{font-size:12px;color:var(--ink3);margin-top:3px;line-height:1.55;}
.opt-price{flex:none;text-align:right;}
.opt-price .n{font-size:20px;font-weight:800;color:var(--accent);line-height:1;font-variant-numeric:tabular-nums;}
.opt-price .n small{font-size:12px;font-weight:700;}
.opt-price .s{font-size:11px;color:var(--ink4);margin-top:3px;}
.view-tip{font-size:12.5px;color:var(--ink3);line-height:1.75;margin-top:4px;}
.view-tip a{color:var(--brand);}

.fld{margin-bottom:14px;}
.fld label{display:block;font-size:13px;font-weight:600;color:var(--ink2);margin-bottom:7px;}
.fld label .req{color:var(--accent);}
.fld label .sub{font-weight:400;color:var(--ink4);font-size:12px;}
.ipt{
  width:100%;height:46px;padding:0 14px;border:1.5px solid var(--line);border-radius:11px;
  background:#FBFCFE;font-size:15px;color:var(--ink);transition:.2s;
}
.ipt:focus{border-color:var(--brand);background:#fff;box-shadow:0 0 0 3px rgba(91,108,255,.1);}
.ipt.err{border-color:#F04438;background:#FFF6F5;}
.ipt::placeholder{color:var(--ink4);}
.ipt-group{display:flex;}
.ipt-group .ipt{flex:1;}
.code-btn{
  flex:none;width:108px;height:46px;margin-left:9px;border-radius:11px;font-size:13px;font-weight:700;
  color:var(--brand);background:#EEF0FF;border:1px solid #DDE1FF;transition:.2s;
}
.code-btn:disabled{color:var(--ink4);background:#F2F4FA;border-color:var(--line);cursor:not-allowed;}
.err-msg{font-size:12px;color:#F04438;margin-top:6px;display:none;}
.err-msg.show{display:block;}
.agree{display:flex;align-items:flex-start;gap:8px;margin-top:4px;font-size:12.5px;color:var(--ink3);line-height:1.65;}
.agree-chk{
  width:18px;height:18px;border-radius:5px;border:1.5px solid #D6DAE8;flex:none;margin-top:2px;
  display:flex;align-items:center;justify-content:center;background:#fff;transition:.2s;
}
.agree.on .agree-chk{background:var(--brand);border-color:var(--brand);}
.agree-chk .icon{width:11px;height:11px;color:#fff;stroke-width:3.2;opacity:0;}
.agree.on .agree-chk .icon{opacity:1;}
.agree a{color:var(--brand);}

.pay-list{margin-top:20px;}
.pay{display:flex;align-items:center;gap:11px;margin-bottom:9px;padding:13px 14px;border:2px solid var(--line);border-radius:var(--radius);cursor:pointer;transition:.2s;}
.pay.on{border-color:var(--brand);background:#F7F8FF;}
.pay-ico{width:30px;height:30px;border-radius:9px;flex:none;display:flex;align-items:center;justify-content:center;color:#fff;}
.pay-ico .icon{width:17px;height:17px;}
.pay-ico.wx{background:#07C160;}
.pay-ico.ali{background:#1677FF;}
.pay-ico.dy{background:linear-gradient(135deg,#25F4EE,#FE2C55);color:#111;}
.pay-body{flex:1;font-size:14.5px;font-weight:600;color:var(--ink);}
.pay-body small{display:block;font-size:11.5px;color:var(--ink4);font-weight:400;margin-top:2px;}
.pay-title{font-size:13px;font-weight:600;color:var(--ink2);margin-bottom:9px;}

.summary{padding:13px 15px;border-radius:var(--radius);background:#F7F8FC;margin-bottom:15px;}
.summary-row{display:flex;justify-content:space-between;font-size:13.5px;color:var(--ink3);line-height:2;}
.summary-row b{color:var(--ink);font-weight:600;}
.summary-row.total{font-size:15px;color:var(--ink);font-weight:700;padding-top:8px;margin-top:6px;border-top:1px dashed #DFE3EF;}
.summary-row.total .amt{color:var(--accent);font-size:20px;font-weight:800;font-variant-numeric:tabular-nums;}

.succ{text-align:center;padding:14px 0 6px;}
.succ-ico{
  width:66px;height:66px;margin:0 auto 16px;border-radius:50%;background:linear-gradient(135deg,#12B76A,#3ECF8E);color:#fff;
  display:flex;align-items:center;justify-content:center;box-shadow:0 10px 28px rgba(18,183,106,.32);
  animation:pop .45s cubic-bezier(.34,1.56,.64,1);
}
.succ-ico .icon{width:32px;height:32px;stroke-width:2.6;}
@keyframes pop{0%{transform:scale(.3);opacity:0}100%{transform:scale(1);opacity:1}}
.succ h3{font-size:19px;font-weight:800;color:var(--ink);}
.succ p{margin-top:8px;font-size:13.5px;color:var(--ink3);line-height:1.7;}
.succ-order{margin-top:16px;padding:13px;border-radius:var(--radius);background:#F7F8FC;font-size:13px;color:var(--ink2);line-height:1.9;text-align:left;}
.succ-order span{color:var(--ink3);display:inline-block;width:76px;}
.succ-order .copy{float:right;font-size:12px;color:var(--brand);font-weight:600;}
.succ-tip{margin-top:14px;padding:12px;border-radius:10px;background:#FFFAF0;border:1px solid #FFE9C7;font-size:12.5px;color:#96601C;line-height:1.75;text-align:left;}

.doc-body{font-size:13px;color:var(--ink2);line-height:1.85;}
.doc-body h4{font-size:14.5px;font-weight:800;color:var(--ink);margin:18px 0 8px;}
.doc-body h4:first-child{margin-top:0;}
.doc-body p{margin-bottom:9px;}
.doc-body ol,.doc-body ul{margin-bottom:9px;}
.doc-body li{padding-left:18px;position:relative;margin-bottom:4px;}
.doc-body ol{counter-reset:dn;}
.doc-body ol li{counter-increment:dn;}
.doc-body ol li::before{content:counter(dn) ".";position:absolute;left:0;color:var(--brand);font-weight:600;}
.doc-body ul li::before{content:"";position:absolute;left:4px;top:12px;width:4px;height:4px;border-radius:50%;background:var(--brand);}

.toast{
  position:fixed;left:50%;top:50%;transform:translate(-50%,-50%);z-index:200;max-width:76%;
  padding:12px 18px;border-radius:12px;background:rgba(15,18,34,.9);color:#fff;font-size:14px;
  text-align:center;line-height:1.6;opacity:0;visibility:hidden;transition:.22s;
}
.toast.show{opacity:1;visibility:visible;}

.kefu-panel{text-align:center;}
.kefu-ico{
  width:56px;height:56px;margin:0 auto 14px;border-radius:16px;color:#fff;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));
  display:flex;align-items:center;justify-content:center;
}
.kefu-ico .icon{width:26px;height:26px;}
.kefu-item{display:flex;justify-content:space-between;align-items:center;justify-content:space-between;margin-bottom:9px;padding:13px 15px;border-radius:var(--radius);background:#F7F8FC;font-size:14px;}
.kefu-item span:first-child{color:var(--ink3);}
.kefu-item b{color:var(--ink);font-weight:700;}
.kefu-item .cp{color:var(--brand);font-weight:600;font-size:12.5px;margin-left:8px;}
.kefu-note{font-size:12.5px;color:var(--ink3);line-height:1.75;margin-top:14px;text-align:left;}

/* 视频播放弹窗 */
.mask-v{align-items:center;padding:0 16px;}
.vbox{
  width:100%;max-width:560px;background:#fff;border-radius:16px;overflow:hidden;
  display:flex;flex-direction:column;transform:scale(.94);opacity:0;
  transition:transform .25s cubic-bezier(.32,.72,0,1),opacity .25s;box-shadow:var(--shadow-lg);
}
.mask-v.show .vbox{transform:scale(1);opacity:1;}
.vbox-h{display:flex;align-items:center;gap:10px;padding:13px 16px;border-bottom:1px solid var(--line);flex:none;}
.vbox-h h3{flex:1;font-size:15.5px;font-weight:800;color:var(--ink);}
.vbox-b{flex:none;background:#000;}
.vbox-b video{width:100%;max-height:60vh;display:block;background:#000;}
.vbox-note{
  padding:11px 16px;font-size:12px;color:var(--ink3);line-height:1.7;background:#fff;
  border-top:1px solid var(--line);
}

.totop{
  position:fixed;right:14px;bottom:calc(96px + env(safe-area-inset-bottom));z-index:70;
  width:42px;height:42px;border-radius:50%;background:#fff;color:var(--ink2);
  box-shadow:var(--shadow-lg);display:flex;align-items:center;justify-content:center;
  opacity:0;visibility:hidden;transition:.25s;
}
.totop.show{opacity:1;visibility:visible;}
.totop .icon{width:18px;height:18px;}

.loading{display:inline-block;width:16px;height:16px;border:2px solid rgba(255,255,255,.4);border-top-color:#fff;border-radius:50%;animation:spin .7s linear infinite;}
@keyframes spin{to{transform:rotate(360deg)}}

/* ============ PC 增强 ============ */
@media (min-width:768px){
  :root{--wrap:900px;}
  body{font-size:15.5px;}
  .topbar-in{height:60px;padding:0 24px;}
  .topnav{display:flex;}
  .topnav a{cursor:pointer;}
  .subnav-in{justify-content:center;overflow:visible;padding:10px 24px;}
  .subnav a{cursor:pointer;margin:0 4px;}
  .subnav a:hover{background:#E9ECF7;}
  .subnav a.on:hover{background:linear-gradient(135deg,var(--brand),var(--brand-2));}
  .hero{padding:56px 0 60px;}
  .hero-in{max-width:900px;margin:0 auto;padding:0 32px;text-align:center;}
  .hero h1{font-size:40px;margin-top:20px;line-height:1.3;}
  .hero-sub{font-size:16px;max-width:680px;margin:14px auto 0;}
  .hero-chips{justify-content:center;}
  .hero-price{justify-content:center;}
  .hero-btns{justify-content:center;}
  .btn{flex:none;height:52px;padding:0 34px;font-size:16.5px;}
  .btn-ghost{width:auto;padding:0 30px;}
  .trust{justify-content:center;}
  .hero-cards{max-width:900px;margin:36px auto 0;padding:0 32px;}
  .hcard{margin-right:16px;padding:20px 22px;}
  .hcard h4{font-size:17px;}
  .hcard p{font-size:13.5px;}
  .sec{padding:56px 0;}
  .sec-in{max-width:900px;margin:0 auto;padding:0 32px;}
  .sec-head h2{font-size:30px;}
  .sec-head p{font-size:14.5px;}
  .pain-list{grid-template-columns:1fr 1fr;gap:14px;}
  .pain{margin-bottom:0;padding:20px;}
  .pain h4{font-size:16px;}
  .pain p{font-size:13.5px;}
  .gain-grid{grid-template-columns:repeat(3,1fr);gap:14px;}
  .gain{padding:22px 20px;}
  .gain h4{font-size:16px;}
  .gain p{font-size:13.5px;}
  .tabs{max-width:560px;margin:0 auto 22px;}
  .tab{cursor:pointer;padding:14px;}
  .tab:hover{box-shadow:0 10px 26px rgba(18,24,58,.14);}
  .syl{cursor:pointer;}
  .syl-h{padding:16px 20px;}
  .syl-b-in{padding:0 20px 16px 56px;font-size:14px;}
  .syl-meta{margin:0 20px 16px 56px;}
  .works{grid-template-columns:repeat(3,1fr);gap:14px;}
  .work{transition:transform .25s,box-shadow .25s;}
  .work:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);}
  .teacher-wrap{display:grid;grid-template-columns:1fr 1fr;gap:14px;}
  .teacher{margin-bottom:0;padding:22px;align-items:flex-start;}
  .t-ava{width:68px;height:68px;font-size:24px;}
  .people{grid-template-columns:1fr 1fr;gap:14px;}
  .pbox{padding:24px;}
  .guar{grid-template-columns:repeat(4,1fr);gap:14px;}
  .guar-item{padding:20px 14px;}
  .revs{grid-template-columns:1fr 1fr;gap:14px;}
  .plans{grid-template-columns:repeat(3,1fr);gap:16px;align-items:start;}
  .plan{padding:26px 22px;}
  .plan:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);}
  .plan.sel:hover{transform:translateY(-6px);}
  .plan h4{font-size:18px;}
  .plan-price .n{font-size:36px;}
  .faq-q{padding:17px 20px;font-size:15px;cursor:pointer;}
  .faq-q:hover{background:#FAFBFF;}
  .faq-a-in{padding:0 20px 17px 47px;font-size:14px;}
  .notice{padding:26px;}
  .notice li{font-size:13.5px;}
  .footer-in{max-width:900px;margin:0 auto;padding:0 32px;}
  .dock{padding:12px 0;background:rgba(255,255,255,.9);}
  .dock-in{max-width:900px;padding:0 32px;}
  .dock-buy{height:50px;padding:0 40px;font-size:17px;}
  .dock-kefu{width:50px;height:50px;}
  .dock-price .n{font-size:30px;}
  .mask{align-items:center;}
  .sheet{max-width:560px;border-radius:22px;max-height:88vh;}
  .sheet-sm{max-width:460px;}
  .opt{padding:16px;}
  .opt:hover{border-color:#C6CCE8;}
  .pay:hover{border-color:#C6CCE8;}
  .plan-btn{cursor:pointer;}
  .dock-buy,.btn-kefu{cursor:pointer;}
  .totop{bottom:110px;right:calc(50% - 450px + 32px);}
}
@media (min-width:1024px){
  :root{--wrap:1080px;}
  .hero-in,.sec-in,.hero-cards,.footer-in,.dock-in{max-width:1080px;}
  .hero h1{font-size:46px;}
  .totop{right:calc(50% - 540px + 32px);}
}